SP 53-101-98 Manufacture and quality control of steel building structures

Type of document:
SP (Code of Rules)

Host body: Gosstroy of Russia

Status: Active

Document type: Normative and technical document
Effective date: January 1, 1999
Published:

Code of Practice for Design and Construction

SP 53-101-98

"Production and quality control of steel building structures"
(approved by the Decree of the Gosstroy of the Russian Federation dated May 17, 1999 No. 37)

Production and quality control of steel structures

1 area of ​​use

The joint venture does not apply to steel structures:

Railway and road bridges;

Reservoirs and gas holders;

Cases of blast furnaces and cowpers;

Hydraulic structures.

For approval during the development of design and technological documentation;

To control the quality of production steel structures.

SNiP II-23-81* Steel structures

SNiP 2.03.11-85 Corrosion protection of building structures

GOST 23118-78 Construction metal structures. General specifications

GOST 9.032-74 Paint coatings. Classification and designations

GOST 9.105-80 Paint coatings. Classification and main parameters of staining methods

GOST 9.303-84 Metallic and non-metallic inorganic coatings. General requirements

GOST 9.402-80 Paint and varnish coatings. Preparation of metal surfaces before painting

GOST 164-90 Height gauges. Specifications

GOST 166-89 Calipers. Specifications

GOST 427-75 Steel rulers. Specifications

GOST 1759.0-87 Bolts, screws, studs and nuts. Specifications

GOST 1759.1-82 Bolts, screws, studs, nuts and screws. Tolerances, methods (ST SEV 2651-80) for controlling dimensions and deviations in the shape and location of surfaces

GOST 1759.4-87 Bolts, screws and studs. Mechanical properties and test methods

GOST 1759.5-87 Nuts. Mechanical properties and test methods

GOST 2246-70 Welded welding wire

GOST 3749-77 Calibration squares. Specifications

GOST 5264-80 Manual arc welding. Connections are welded. Main types, structural elements and dimensions

GOST 5378-66 Goniometers with vernier. Specifications

GOST 6996-66 Welded joints. Methods for determining mechanical properties

GOST 7502-89 Metal tape measures. Specifications

GOST 7505-89 Stamped steel forgings. Tolerances, allowances and forging overlaps

GOST 7512-82 Non-destructive testing. Connections are welded. radiographic method

GOST 8050-85 Gaseous and liquid carbon dioxide. Specifications

GOST 8420-74 Paintwork materials. Methods for determining the relative viscosity

GOST 8479-70 Structural carbon and alloy steel forgings. General specifications

GOST 8713-79 Submerged arc welding. Connections are welded. Main types, structural elements and dimensions

GOST 9087-81 Fused welding fluxes

GOST 9150-81 Basic norms of interchangeability. The thread is metric. Profile

GOST 9467-75 Coated metal electrodes for manual arc welding of structural and heat-resistant steels. Types

GOST 10157-79 Gaseous and liquid argon. Specifications

GOST 10549-80 Thread exit. Runs, undercuts, grooves and chamfers

GOST 11533-75 Automatic and semi-automatic submerged arc welding. Connections are welded at acute and obtuse angles. Main types, structural elements and dimensions

GOST 11534-75 Manual arc welding. Connections are welded at acute and obtuse angles. Main types, structural elements and dimensions

GOST 14771-76 Shielded arc welding. Connections are welded. Main types, structural elements and dimensions

GOST 14782-86 Non-destructive testing. Welded seams

GOST 15140-78 Paintwork materials. Methods for determining adhesion

GOST 16093-81 Metric thread for diameters from 1 to 600 mm. Tolerances

GOST 18123-82 Washers. General specifications

GOST 19282-73 Steel, low-alloyed, thick-plate and universal broadband

GOST 19903-74 Hot-rolled sheet steel. Assortment

GOST 22261-94 Instruments for measuring electrical and magnetic quantities. General specifications

GOST 22353-77 High-strength bolts. Designs and dimensions

GOST 22354-77 High-strength nuts. Designs and dimensions

GOST 22355-77 Washers for high-strength bolts. Designs and dimensions

GOST 22356-77 High-strength bolts and nuts and washers. General technical requirements

GOST 23518-79 Shielded arc welding. Joints welded at acute and obtuse angles

GOST 24705-81 Basic norms of interchangeability. The thread is metric. Main dimensions

GOST 26047-83 Building steel structures. Conventions(brands)

GOST 27772-88 Rolled products for building steel structures. General specifications

3 General provisions

3.1 The manufacture of steel building structures (hereinafter - SSC) is carried out by enterprises and organizations that have state licenses of the Russian Federation, giving the right to manufacture structures of the corresponding groups according to the classification adopted in SNiP II-23-81 *.

3.2 General requirements for the design and manufacture of SSC are set out in the SP in accordance with the requirements of SNiP II-23-81*.

3.3 To launch the production of structures, the manufacturer, on the basis of design documentation, develops technological documentation, the form and volume of which depend on the specifics of production and the complexity of the products.

For unique structures, special technical requirements are developed.

4 Acceptance design documentation, incoming control and storage of rolled metal products, welding and paintwork materials, fasteners

4.1 All design documentation incoming to the enterprise must be reviewed and analyzed in order to:

Error detection;

Checking the assembly of structures (for typical objects);

Project manufacturability assessments;

Evaluation of the economic feasibility of manufacturing structures in a specific production environment;

Coordination of changes in steel grades, design solutions for units and types of connections.

With a positive result of checking the design documentation, the technical manager of the enterprise makes a decision to transfer the object to production. For complex and unique objects, the decision is made at the technical council of the enterprise.

Rolled metal products (rolled products), welding, paint and varnish materials and fasteners arriving at the enterprises from suppliers, upon acceptance, must be checked by the technical control service of the enterprise in terms of quantity, completeness and compliance with standards, specifications (TU), supply contracts, work orders.

4.2 The type and plan of input control is established by the technical services of the enterprise, if necessary, in agreement with the supplier.

4.3 An acceptance certificate must be drawn up for each accepted rolled metal car, type of rolled metal, steel grade, melt.

4.3.1 Upon acceptance of rental, the following should be checked:

Quantity by theoretical weight, assortment and grades of steels according to work orders, stamps or tags of the supplier enterprise;

The absence of delaminations, cracks, shells, sunsets, dents and general deformations that are visible in the rental, exceeding those allowed by the relevant standards and specifications.

4.3.2 If there are deviations from the requirements of the standard or specifications, it is necessary to draw up a reclamation report.

4.3.3 After acceptance, additional marking of rolled products is carried out: the number of the acceptance certificate is applied with white paint and the steel grade is applied in color in accordance with the system adopted at the enterprise.

4.3.4 At the metal warehouse, computer, card-index or journal accounting of the movement of rolled products should be kept according to its arrival and consumption. Accounting should be kept for each profile of rolled products, taking into account the steel grade and the number of the acceptance certificate.

4.4 When accepting welding and paintwork materials, fasteners, the following rules must be observed.

4.4.1 Check the availability of an accompanying document, which should indicate the name of the material, batch number and indicators certifying the compliance of the material with the requirements of regulatory and technical documentation (NTD).

4.4.2 Determine the integrity of the packaging by external inspection.

4.4.3 Determine the amount of materials by weighing, piece counting, theoretically.

4.4.4 The results of acceptance are drawn up by an acceptance certificate and included in the general system of movement of materials at the enterprise.

4.4.5 If necessary, apply the acceptance certificate number on the container with paint, and the expiration date on the container of paints and varnishes.

4.5 Rolled products must be stored in a warehouse sorted by profiles and steel grades.

Rolled products should be stored indoors, equipped with special devices that provide mechanization of intra-warehouse operations.

Rolled steel should be stored in racks with dividing racks, and rolled sheets - in specially equipped places, serviced by cranes with magnetic washers.

Coils should be stored vertically or on special pallets in a horizontal position. Cranes serving coiled steel warehouses must be equipped with special grippers.

Rolled products should be stored in equipped mechanized warehouses in accordance with the design and technological documentation for this warehouse and the instructions developed by the enterprise.

It is possible to carry out temporary storage (within 3 months from the date of shipment by the manufacturer) of profiled steel in specially equipped racks in the open air.

4.6 Welding consumables (welding wire, electrodes, flux, flux-cored wire) should be stored separately by brands and batches in a warm and dry room in their original packaging or special containers.

4.7 Paints and varnishes should be stored in the original container in specially equipped rooms that provide fire safety and security environment.

4.8 Fasteners (bolts, nuts, washers) should be stored in original or special containers indoors. With a long period of storage, if necessary, it is necessary to restore the conservation protective coatings.

5 Preparation of rolled metal products, welding and paintwork materials before submission to production

5.1 Before being put into production, rolled products must be checked for compliance with the accompanying documentation, cleaned from moisture, snow, ice, oil and other contaminants.

5.2 Straightening of rolled products, depending on the profile, should be carried out on sheet straightening and sorting machines and presses in a cold state.

The maximum allowable deflection values ​​after cold straightening are given in Table 1.

5.3 Straightening of steel by local flame heating is acceptable gas burners, while the temperature of the heating zone should not exceed 800 °C for hot-rolled and normalized steels, and for thermally improved steels - 700 °C.

5.4 After straightening, the rental must meet the following requirements:

5.4.1 Have no cracks or delaminations. It is allowed to have local dents in the thickness and width of rolled products to a depth not exceeding twice the minus tolerance for this type of rolled products, provided for by the relevant GOST or TU, but in all cases not more than 1 mm in thickness and 3 mm in cross-sectional dimensions.

5.4.2 The discrepancy between the plane of sections of profiled products should not exceed the appropriate tolerances established by GOST or TU for this type of rental.

5.4.3 Limit deflections of profiled steel along the entire length of the element should not exceed 0.001 l≤ 10 mm, and deflections of local curvature - 1 mm over a length of 1.0 m.

5.4.4 The flatness of sheet metal must comply with GOST 19903.

5.5 Welding consumables are fed to workplace marked in the amount necessary for work during the day.

5.5.1 Welding wire must be cleaned from rust, grease and other contaminants to a metallic sheen (except for copper-plated wire), wound into coils, cassettes or wound on coils.

Table 1

5.5.2 Electrodes and fluxes must be calcined in accordance with the modes specified in GOST or TU and passports for this type of welding material.

5.5.3 Cored wire must be cleaned, annealed and rewound into coils, cassettes or spools.

5.6 Before use, paints and varnishes must be brought to the parameters established by the technological regulations and NTD for a specific material.

Preparation of paints and varnishes for use consists of mixing operations until a homogeneous consistency is obtained without sediment at the bottom of the container, introducing, if necessary, the required amount of hardeners, driers and other additives, diluting to a working viscosity and filtering.

5.7 All operations for the preparation of paints and varnishes should be performed in the paint preparation department.

The temperature of the paintwork material must be equal to the air temperature in the paint preparation department, for which the materials from the warehouse must arrive no later than a day before their use. The temperature in the paint preparation department must be at least +15 °С.

5.8 Dilution of paints and varnishes to working viscosity must be carried out with solvents in accordance with the NTD for a specific material and the requirements of the technological regulations.

5.9 The working viscosity of paints and varnishes is determined according to GOST 8420 with a B3-246 viscometer.

5.10 Submission to workplaces prepared for use of paints and varnishes should be made in a closed container. When consuming more than 200 kg (of one item) per shift, it is advisable to supply paintwork materials centrally through pipes.

6 Marking, basting, making templates and conductors

6.1 Marking on rolled metal and making templates should be carried out using metal rulers and tape measures that correspond to the accuracy of the second class according to GOST 7502 and GOST 427, calipers according to GOST 166, gage gauges according to GOST 164, calibration squares according to GOST 3749, goniometers with vernier according to GOST 5378.

6.2 When marking on rolled metal and making templates, it is necessary to take into account machining allowances and welding shrinkage in accordance with the recommendations in Table 2.

table 2

Table 3

Table 4

Picture 1

Figure 2

Figure 3

Figure 4

6.3 Marking on rolled metal and marking according to templates should be done with scribers and center punches. The centers of the holes should be additionally punched with a center punch to a depth of at least 2 mm.

6.4 Drilling jigs should be made of steel, while the pressed-in bushings should be hardened.

The conductors shall be manufactured to the accuracy given in Table 3.

The conductors must be accepted by the Quality Control Department and marked with the date of inspection. As you work, you should perform repeated accuracy checks (when manufacturing designs for a new order).

6.5 Templates must be made from materials (metal, wood, plastic, cardboard, etc.) that provide the required quality of templates, taking into account the repeatability of their use in the manufacture of parts. The maximum deviations of the dimensions of the templates should be two times less than the values ​​given in table 4.

6.6 Marking templates should contain: order number, drawing and details; number of parts, diameter and number of holes (if any).

7 Cutting and machining in the manufacture of parts

7.1 Cutting of profiled steel can be carried out on press shears, in dies, friction and abrasive saws, toothed saws, manual, machine and thermal cutting without subsequent machining of the ends of the parts. These processing methods are acceptable for any steel grades and any operating conditions of structures.

7.2 The ends of profiled rolled parts, regardless of the processing method, should not have cracks, as well as burrs and blockages of more than 1 mm.

7.3 Cutting of sheet metal should be carried out on guillotine shears, notching machines, in dies, manual and machine thermal cutting.

7.4 Cutting of sheet metal using guillotine shears, notching machines and dies should not be performed in the manufacture of parts:

From steels with a normative yield strength of more than 350 MPa;

More than 25 mm thick from steels with a normative yield strength of more than 275 MPa;

More than 16 mm thick from steels with a standard yield strength of 285 - 350 MPa.

7.5 It is forbidden to cut sheet metal using guillotine shears, notching machines and dies when manufacturing parts from any steel grades:

Structures of groups I and II in accordance with the classification of SNiP II-23-81 *, working in tension, the longitudinal edges of which remain free after assembly and welding, including butt plates;

Gussets for truss and truss trusses, spans of conveyor galleries, as well as gussets of other structures of group I in accordance with the classification of SNiP II-23-81 *.

7.6 The edges of the parts after cutting on guillotine shears, notching machines and in dies should not have cracks, delaminations, burrs and blockages of more than 1 mm.

7.7 It is possible to use without restrictions cutting on guillotine shears, notching machines and dies with subsequent machining of the edges by a value of at least 0.2 of the sheet metal thickness.

7.8 In other cases, with the exception of the above, cutting on guillotine shears, notches and dies should be allowed without restrictions.

7.9 The parameters of the modes of mechanical processing of structural parts should be determined taking into account the main indicators of the mechanical properties of rolled steel: yield strength, tensile strength, elongation, and hardening modulus. The recommended values ​​of these indicators for use in calculating the mode parameters are given in Appendix A.

7.10 Thermal cutting is possible in the manufacture of sheet parts from steels of any grade operating in any operating conditions.

7.11 The edges of parts formed by thermal cutting must be deburred.

7.12 The edges of sheet parts of structures of groups I and II (in accordance with the classification of SNiP II-23-81 *), working in tension, the edges of the gussets remaining free after assembly and welding in truss and truss trusses, spans of conveyor galleries must comply with the following requirements :

The surface roughness should not exceed 0.3 mm;

It is permissible to have separate places on the edges that do not meet the specified requirements, as well as snags that do not bring the size of the part out of tolerance, corrected by smooth cleaning with an abrasive wheel or welding using a special technology, followed by cleaning of the correction points with an abrasive wheel moving along the edge.

The edges of parts that do not meet the specified requirements are subject to machining.

7.13 In other cases, except for paragraphs. 7.9 - 7.12, the edges of sheet parts performed by thermal cutting can have a roughness of up to 1.0 mm, and individual snags - up to 1.5 mm. Correction of cutting defects should be carried out in accordance with 7.11 of this SP.

7.14 Cutting edges for welding must be performed by thermal cutting or machining. In terms of surface quality, the cut must comply with the requirements set out in 7.12. The geometric dimensions and shape of the grooves must comply with the requirements of the standards for welded joints.

7.15 Deviations of the edge lines of sheet parts to be assembled and welded, regardless of the processing method, must ensure the requirements of standards for welded joints.

7.16 The ends and surfaces of the parts that directly transmit the support pressures by tight contact must be machined.

7.17 The sharp edges of the ends of parts intended for the manufacture of structures subjected to hot galvanizing or operated in medium and highly aggressive environments must be blunted by at least 1.0 mm.

7.18 Limit deviations of parts are set during the development of project documentation. If there are no tolerances in the design documentation, the data given in Table 4 should be used.

7.19 The control of the geometric dimensions of the parts is carried out with a measuring tool in accordance with 6.1, as well as a set of probes in accordance with TU 2-034-225-87.

The control of the roughness values ​​of the ends of the parts is carried out visually using reference samples.

8 Formation of holes for bolted field connections

8.1 All holes for bolted field connections must be formed to the design diameter at the enterprise, with the exception of those specified in the project documentation.

8.2 The formation of holes should be done by punching or drilling.

8.3 Hole punching is carried out on presses according to a basting, according to templates or using special group stamps and measuring devices.

8.4 The formation of holes by punching is prohibited for steels with a normative yield strength of more than 350 MPa.

8.5 The ratio between the thickness of the metal and the diameter of the hole during punching should not exceed the following values:

For bolts of strength classes 4.6, 4.8, 5.6, 5.8, 8.8 - no more than 0.7 t/db, where t≤ 20mm;

For bolts of strength classes 10.9 and higher - no more than 0.5 t/db, where t≤ 12 mm.

8.6 It is forbidden to punch holes in structures of group I in accordance with SNiP II-23-81 * with a ratio of metal thickness and hole diameter of more than 0.5 t/db.

8.7 In cases not provided for in paragraphs. 8.4 - 8.6, the formation of holes by punching can be allowed without restrictions.

8.8 Hole drilling should be performed on drilling machines using a basting, conductors or using measuring devices.

8.9 The formation of holes by drilling is permissible in the manufacture of structures without restrictions.

8.10 The nominal diameters of holes for bolts, as a rule, should be made 2 - 3 mm more than the nominal diameter of the bolt specified in the project documentation, except for the cases specified in this SP.

8.11 Limit deviations of hole diameters depending on the method of formation are given in Table 5.

Table 5

In millimeters

8.12 The maximum displacements of the centers of the holes are set in the design documentation from the condition of the assembly of structures during installation.

8.13 In the absence of relevant instructions in the project documentation, the maximum deviations of dimensions between the centers of the holes are assigned in accordance with the following rules.

Between any two holes, including diagonally:

Within the group - ±1.5 mm,

Between groups (with distance between groups L)

up to 6 m - ±3 mm,

over 6 m - ±0.0005 L.

Distances of the axes of the holes from the edge of the parts:

Influencing the assembly of structures (supporting ribs, elements with milled ends, elements joined at the same level, etc.) - ± 1 mm,

Not affecting the collection - ± 2 mm.

9 Bending parts, flattening the ends of closed profiles

9.1 In the manufacture of structures, the following types of cold deformation of rolled products should be used:

Bending of sheet and profile rolled products along the radius;

Bending of sheet metal "into the corner";

Flattening of the ends of pipes and bend-welded closed profiles.

9.2 Bending along the radius must be carried out on sheet bending, profile bending machines and in presses. Permissible minimum bending radii for the main types of rolled products from steels with a standard yield strength of up to 275 MPa are given in table 6.

9.3 When bending parts made of steels with a standard yield strength of more than 275 MPa, the values ​​​​of the permissible minimum bending radii are increased by a factor equal to

9.4 For parts used in group I structures according to SNiP II-23-81 *, the allowable minimum bending radii for steels of the corresponding strength are increased by 1.3 times.

9.5 When bending along the radius, the finished parts must meet the following requirements:

The gap between the surface of the part and the template on the length of the template 1 m should not exceed 2 mm;

The displacement of the edges of the cross section of profile parts should not exceed three times the maximum tolerance for the corresponding type of rolled products.

9.6 It is allowed to submit parts for assembly that do not meet the requirements of 7.5, with subsequent calibration, bending and straightening during the assembly process.

9.7 It is allowed to perform bending along the radius in conductors using local heating and forging of heated places. This method should be used when bending and straightening parts from profiled products.

When performing these types of operations, the following rules must be observed:

Steels with a standard yield strength up to 350 MPa inclusive should be heated to a temperature of 900 - 1000 ° C;

Steel supplied in a normalized state should be heated to a temperature of 900 - 950 ° C;

When bending and straightening steel of all strength classes with local heating, forging must be completed at a temperature not lower than 700 °C.

9.8 When bending on rollers sheet parts having welded joints with a thickness of 16 mm or more, the reinforcement of the welds must be removed or be no more than 2 mm.

9.9 Corner bending must be done on bending presses and in dies.

When bending into a corner for steels with a standard yield strength of up to 350 MPa, the minimum inner radius must be at least 1.2 thickness for structures of groups III and IV and at least 2.5 thickness for structures of groups I and II.

When bending into a corner, the edges of parts made of steels with a normative yield strength of more than 275 MPa, formed by knife cutting and located perpendicular to the bend line, must be processed in the area of ​​the bend line with an abrasive wheel.

Corner bending of parts made of steels with a normative yield strength of more than 350 MPa is unacceptable.

9.10 When manufacturing standard bent profiles at the enterprise, the maximum permissible deviations of the geometric dimensions of the form should not exceed the requirements of the standards for these types of profiles by more than 2 times.

9.11 Other bent parts must comply with the following requirements:

Deviation of the bending line from the design position is not more than 2 mm;

The tangent of the bend angle should not differ from the design by more than 0.01.

9.12 Checking the geometric dimensions of bent parts should be carried out with a measuring tool in accordance with 6.1 and specially made templates.

Table 6

10 Part marking

10.1 Marking of parts must be applied with indelible paint indicating the order number, drawing number and part.

It is allowed to mark one control part with paint, to mark other parts with chalk, and not to mark when stored in piles or containers.

10.2 On the design details of critical structures, according to the design documentation, the heat numbers should be stamped. The locations of the stamps of the melts must be indicated in the project documentation.

11 Assembly of structures for welding

11.1 Assembly of structures to be welded should be performed only from parts that meet the requirements of sections 3-8 of this SP.

11.2 During the assembly process, it is necessary to maintain the geometric dimensions of the structures, the location of the groups of holes, the gaps between the ends of the parts and the alignment of their planes at the joints to be welded, the centering of the rods in the nodes of the lattice structures, the tightness of the adjoining parts to each other in the places of force transfer by tight touch.

11.3 Limit deviations of the geometric dimensions of the assembly unit transferred for welding should not exceed the allowable deviations given in the design documentation. In the absence of instructions on the tolerances in the drawings, the requirements given in Table 7 should be observed.

Table 7

11.4 The gap and offset of the edges of parts assembled for welding must comply with the requirements of GOST 5264, GOST 8713, GOST 14771, GOST 22261.

11.5 The assembly of structures should be carried out according to the marking, according to the copiers and in the conductors.

The choice of the assembly method is determined by the enterprise, depending on the type of structure and the required accuracy of its manufacture, with the exception of bracing elements, the assembly of which in conductors and copiers is mandatory.

11.6 Copiers for assembling lattice structures should be made, as a rule, from the same parts as the structure being assembled.

The accuracy of the manufacturing of copiers must ensure the required accuracy of manufacturing structures, while the maximum deviations of the dimensions of the copiers must be two times less than the corresponding dimensional deviations adopted for structures.

11.7 The accuracy of manufacturing assembly conductors is set according to the working drawings, depending on the required accuracy of the manufactured structures.

11.8 Fastening parts during assembly should be carried out with tacks. When performing tacks, the following requirements must be observed:

Tacks of assembled parts in the structure must be located only in places where welds are applied;

The leg of the seam of the tacks is assigned the minimum depending on the thickness of the elements to be joined in accordance with SNiP II-23-81 *;

The length of the welding seam of the tack must be at least 30 mm, the distance between the tacks - no more than 500 mm, the number of tacks on each part - at least two;

Welding consumables for tacks must ensure the quality of the deposited metal corresponding to the quality of the weld metal according to the design documentation;

Tacks are performed by workers who have the right to access welding work;

When assembling structures of a large mass, the dimensions and arrangement of tacks are determined by the technological documentation, taking into account the forces arising during tilting and transportation.

11.9 The assembled structures must be marked with white oil paint indicating the factory order number, drawing number, brand of the assembly unit and its production serial number. Marking can be carried out using tags attached to the product.

11.10 Before submitting the structure for welding, it is necessary to check the quality of the assembly and, if necessary, correct the existing defects.

11.11 Compliance with the geometric dimensions of the assembly units of the design documentation, as well as the requirements of the relevant GOST for the joints of the parts of the assembly units to be welded, is subject to mandatory control.

11.12 In the absence of direct instructions in the design documentation on the accuracy of manufacturing, the requirements for the values ​​of limit deviations given in Table 7 should be met.

12.1 Welding of steel structures should be carried out according to the technological process developed at the enterprise, drawn up in the form of standard or special technological instructions, maps, etc., which should take into account the features and state of production.

12.2 The mechanical properties of the metal of welded joints must comply with the following requirements of GOST 6996:

The tensile strength of the weld metal must not be lower than that of the base metal;

Metal hardness: not higher than 350HV (340HV, 53 HR b) - structures of group I according to SNiP II-23-81* and not higher than 400HV (380HV, 100 HR b) for structures of other groups;

Impact strength on specimens of type VI at a negative temperature specified in the project must not be lower than 29 J/cm 2 , except for joints performed by electroslag welding;

Relative elongation is not less than 16%.

Notes

1 Tests for impact strength are subjected to the metal of butt or tee joints with penetration of the edges.

2 When testing for the impact strength of metal, the fusion boundaries can be lower, but not more than 5 J/cm 2 .

3 If it is necessary to evaluate the impact strength on samples of other types, its norms should be indicated in the project documentation.

12.3 Welding equipment should provide the ability to effectively perform welded joints in accordance with the technological regulations developed at the enterprise. The stability of the parameters of the mode specified in the technological schedule, which is provided by the equipment, must be evaluated during the operational control of the welding process. Control of equipment operation, including verification of measuring instruments installed on it, must be carried out within the framework of the production quality management system in force at the enterprise.

12.4 Depending on the prevailing range of production and specialization of the metal structures manufacturer, along with universal welding equipment (automatic, semi-automatic, welding current power sources, etc.), assembly and welding shops and areas must be equipped with stands, tilters, manipulators and other devices providing conditions for high productivity and stable product quality welding production. The most effective type of equipment for the production of welded structures are automated stands, which combine the processes of assembly and welding.

12.5 The main welding methods used in the manufacture of structures have the following areas of effective application:

Manual arc welding is used to make tacks when assembling structures, when correcting defects in welded joints, when welding seams located in hard-to-reach places or in various spatial positions, when the use of mechanized welding is difficult or impractical;

Automatic submerged arc welding is used mainly in the enlargement of sheet blanks, in welding of connecting seams in elements of a composite section, in the manufacture of tank panels, etc.;

Mechanized welding in shielding gases is a universal and most widely used method of welding in the conditions of a single production pattern prevailing in steel structures plants.

12.6 Detailed requirements for the technology and technique of welding, providing an increase in the quality and reduction of labor intensity of work (welding modes, sequence of operations, techniques, etc.), as well as technological features of arc welding varieties used to increase production efficiency (welding with additional filler material, multi-arc welding, one-sided welding on a forming backing, etc.) should be set out in the technological instructions of enterprises.

12.7 Welding of structures should be performed only after checking the correct assembly of structures by a production or control foreman.

12.8 The edges to be welded and the metal zone adjacent to them with a width of at least 20 mm, as well as the edges of the sheets at the junction of the lead-out strips, before assembly, must be cleaned from moisture, oil, burrs and dirt to clean metal. Immediately before welding, if necessary, cleaning must be repeated, while cleaning products should not remain in the gaps between the assembled parts.

12.9 Welding should be carried out, as a rule, in a spatial position convenient for the welder and favorable for the formation of the seam (lower, "into the boat"). In this case, an excessively large volume of weld metal deposited in one pass is not allowed in order to avoid non-fusion of the weld with welded edges.

12.10 To reduce waste of weld metal and ensure technological capability welds, in which the deviations of dimensions from the design values ​​meet the requirements of the standards, forced welding modes should not be used. This is achieved by limiting the diameters of the electrodes, which in manual welding should not exceed 4 - 5 mm, in semi-automatic welding in shielding gases should be 1.4 - 1.6 mm, in automatic submerged arc welding - 2 - 4 mm.

12.11 It is allowed to perform each bead of a multilayer weld after cleaning the previous bead, as well as tacks, from slag and metal spatter. Portions of seam layers with pores, cavities and cracks must be removed before applying the next layer.

12.12 In case of double-sided welding of seams of butt joints, as well as fillet and tee joints with through penetration, it is necessary to clean the weld root to bare metal before making a seam on the reverse side.

Note- When welding non-critical structures such as transitional platforms, fences, stairs, decking, etc., as well as structures in which stresses do not exceed 0.4 of the design resistance, the weld root may not be removed.

12.13 In the event of a forced break in work, welding may be resumed after cleaning the end section of the weld 50 mm long and the crater from slag; this area and the crater should be completely closed with a seam.

Craters at the ends of the seams must be carefully welded and cleaned.

When welding the transverse seams of the tank panels, it is allowed to start and finish weld on the base metal, while the quality of the beginning and end of each weld must be checked.

12.14 The beginning and end of a butt weld, as well as a fillet weld performed by automatic welding in a tee joint, as a rule, should be led out of the welded parts to lead plates. After welding, these strips are removed by acid cutting, and their installation sites are cleaned with a grinder.

12.15 When welding intersecting butt welds, the reinforcement of the weld made first should be removed flush with the base metal in the intersection zone, if the butt joint does not have a groove, or give it the shape of a groove of the crossing weld.

12.16 Deviations of the dimensions of the joints from the design ones should not exceed the values ​​specified in GOST 5264, GOST 14771, GOST 8713, GOST 11533, GOST 11534, GOST 23518. The dimensions of the fillet weld must ensure its working section, determined by the value of the design value of the leg, taking into account the maximum allowable gap between the welded elements; at the same time, for calculated fillet welds, the excess of the specified gap must be compensated by an increase in the leg of the weld.

12.17 The requirement for a smooth transition of the surface of butt and fillet welds to the base metal shall be substantiated in the design documentation by calculations for endurance or strength, taking into account brittle fracture. To ensure a smooth transition, additional surface treatment should be used by melting it with a non-consumable electrode in an inert gas, plastic compression (“tapping”) or machining in ways that do not leave cuts, notches and other defects. The ability to ensure a smooth transition by selecting welding modes is limited to submerged arc welding of fillet welds.

12.18 Butt joints of pipes with a diameter of up to 800 mm inclusive, regardless of the wall thickness, must be made with a one-sided seam on the remaining backing ring, while the groove of the edges and the gap between the welded elements must ensure complete penetration of the pipe wall. With a pipe diameter of more than 800 mm, butt joints are made with double-sided seams, first of all, a seam is applied from the inside, and then, after cleaning the root of the seam, from the outside.

12.19 As an effective method to prevent or reduce the risk of formation of hot, cold and laminar cracks in welded joints, it is necessary to use preheating of the welded elements to a temperature of 120 - 160 °C.

Preheating should be carried out when welding in shielding gases and manual welding of structures: from steel C390 with a thickness of elements from 30 mm, from steel C440 - with a thickness of elements from 25 mm, as well as when welding root passes of joints and tee joints of elements from this steel with a thickness from 20 mm. An increase in the rigidity of welded joints and a decrease in the temperature of the steel may make it necessary to use preheating when welding elements of smaller thickness, as well as structures made of steel of lower strength classes.

12.20 The seams of welded joints and structures after welding must be cleaned of slag, spatter and metal deposits. Welded assembly fixtures should be removed without impact and damage to the base metal, and the places of their welding should be cleaned to the base metal with the removal of all defects.

12.21 Near the seam of the welded joint, the number or sign of the welder who performed this seam should be placed. The number or sign is affixed at a distance of at least 4 cm from the seam boundary, unless otherwise indicated in the design or technological documentation. When welding an assembly unit by one welder, it is allowed to mark as a whole; in this case, the welder's mark is placed next to the marking of the shipping mark.

12.22 Quality control of welded joints should be carried out within the framework of the product quality management system developed at the enterprise, which establishes the areas of responsibility and the procedure for interaction between technical services and line personnel.

Quality control contains two sequentially implemented groups of activities: operational control, acceptance control (input control is discussed in Section 4).

12.23 Operational control is carried out at all stages of the preparation and execution of welding work, the main provisions of which are set out in this document, namely: preparation and use of welding materials, preparation of edges for welding, assembly, welding technology, supervision of the availability and validity of certificates of welders for the right performance of welding work and compliance of the work performed with the assigned qualifications.

12.24 Control over compliance with the requirements for welding technology and technique should be carried out for compliance with the requirements of technological instructions and technological maps developed at the enterprise, which should take into account the specifics of the equipment and instrumentation used. At the same time, the stability of the equipment operation should be an independent object of operational control.

12.25 Acceptance quality control of welded joints is carried out by the following main methods used in various combinations depending on the design purpose, operating conditions and degree of responsibility: external examination and measurement, ultrasound, radiographic, capillary, bubble, mechanical tests of control samples, etc.

The methods and scope of control are applied in accordance with the instructions of this document, unless other requirements are given in the project documentation. In agreement with design organization other effective methods of control may be used instead of or in addition to those indicated.

12.26 Depending on the design, operating conditions and degree of responsibility, the seams of welded joints are divided into categories I, II and III, the characteristics of which are given in Table 8. Methods and scope of quality control of welded joints are indicated in Table 9.

Control should be carried out on the basis of the requirements of the relevant standards and regulatory and technical documentation. The conclusion on the results of the control must be signed by a flaw detector certified to a level not lower than the 2nd category.

Table 8

Table 9

Notes

1 Methods and scope of control of welded joints in units of increased rigidity, where the risk of cracking increases, should be additionally indicated in the design documentation.

2 In structures and assemblies characterized by the risk of formation of cold and layered cracks in welded joints, quality control should be carried out no earlier than two days after completion of welding.

12.27 Welds that require control using physical methods (ultrasonic, capillary, mechanical tests, etc.), and the scope of such control should be noted in the design documentation in accordance with the requirements of the standard of the enterprise developing the drawings.

Selective control should first of all be subjected to seams in the places of their mutual intersection and in places with signs of defects. If, as a result of selective control, unsatisfactory quality of the seam is established, the control should be continued until the actual boundaries of the defective area are identified.

The control should be carried out before painting the structures.

12.28 During external inspection, welds must meet the following requirements:

a) have a smooth or uniformly scaly surface without sharp transitions to the base metal (the requirement for a smooth transition to the base metal must be specially justified and provided with additional technological methods in accordance with 12.17 of this document);

b) the seams must be tight along the entire length and not have visible burns, narrowing, breaks, sagging, as well as undercuts that are unacceptable in size, lack of penetration at the root of the seam, non-fusion along the edges, slag inclusions and pores;

c) the metal of the weld and the near-weld zone should not have cracks of any orientation and length;

d) the craters of the seams in the places where welding stops must be digested, and in the places where they end - welded.

12.29 According to the results of non-destructive testing, the seams of welded joints must meet the requirements specified in Table 10.

Table 10

12.30 Welded joints that do not meet the requirements for their quality must be corrected. The method of correction is assigned by the welding managers of the enterprise, taking into account the requirements of this document. Defective seams can be corrected in one of the following ways: by mechanical cleaning, by overcooking defective areas, by partially or completely removing them, followed by overcooking.

12.31 Sagging and unacceptable reinforcement of the seams are treated with an abrasive tool. Incomplete seams, unacceptable undercuts, unmelted craters, lack of penetration and lack of fusion along the edges are welded with subsequent cleaning. Seam sections with an unacceptable number of pores and slag inclusions are completely removed and welded again.

12.32 The length and depth of cracks found in the metal of welded joints shall be established. The ends of the crack must be drilled (hole diameter 5 - 8 mm) with an allowance of 15 mm from each end. Then the preparation of the site for welding is carried out by creating a V-shaped cutting of the edges (opening angle 60 - 70 °).

Similarly, the repaired areas are prepared when repairing joints with unacceptable pores, slag inclusions and non-fusion. In welds of types 5, 7 - 12, according to the classification of table 8 of this document, it is allowed to correct pores and slag inclusions by increasing the design section of the welds by welding without preliminary cutting of the metal.

12.33 Welding of a defective area prepared for repair must be carried out, as a rule, by the same welding method that was used to make the seam. Short defective sections and defective sections of any length without cutting or with insignificant cutting of the seam can be corrected by manual arc welding with electrodes with a diameter of 3-4 mm. When welding defects, a metal hardness of no higher than 400 HV should be ensured, which may require preheating of the corrected area.

Undercuts with a depth of not more than 0.5 mm for rolled products up to 20 mm thick and not more than 1 mm for rolled products over 20 mm thick, as well as local undercuts (up to 20% of the weld length) may be corrected by stripping without subsequent welding.

12.34 Repaired sections of seams should be re-inspected.

The results of acceptance control should be drawn up in the form of protocols.

12.35 Residual deformations of structures that have arisen after welding and exceed the values ​​given in Table 7 of this document must be corrected. Correction is carried out by means of mechanical, thermal or thermomechanical effects. During the straightening process, the formation of dents, nicks and other damages on the surface of rolled steel should be excluded.

Parts and elements to be welded should, if possible, be given a preliminary reverse displacement or reverse deformation, compensating for movements and deformations from welding.

12.36 Mechanical straightening after welding should be carried out in rolls (straightening of welded panels or rods), benches for straightening the mushroom shape of shelves (straightening of welded I-beams) and similar devices.

12.37 Thermal and thermomechanical straightening is carried out by local heating of the metal to a temperature not exceeding 700 °C (to avoid softening of heat-treated rolled products). For hot-rolled steel, heating up to a temperature of 900 °C is allowed.

Thermomechanical straightening of complex forms of deformations using static loads (weight, jacks, spacers) should be carried out at a temperature of the heating zones of 650 - 700 °C. In this case, the cooling of the metal below 600 °C is not allowed.

It is forbidden to cool the heated metal with water.

13 Control and general assemblies

13.1 The control and general assembly of structures with field bolted connections must be carried out at the manufacturer, if it is specified in the design documentation, while the quality of the groups of holes made in these connections must comply with the requirements of the regulatory documentation for the installation of structures.

Control assembly of structures is also carried out as a requirement of the technological documentation of the manufacturer of structures during periodic monitoring and testing.

13.2 Completely manufactured elements are subjected to a test assembly before they are primed and painted.

The control assembly must confirm the coincidence of the holes in the field joints, as well as the tightness of the abutment in the joints with the transfer of forces through the surfaces, the absence of gaps and deformations in the joints.

When assembling structures, a sufficient number of bolts and plugs must be supplied in each connection to ensure the invariability of the structure and the safety of the assembly, but not less than one plug and one bolt.

13.3 In the absence of requirements in the regulatory documentation for the installation of structures assembled during the control assembly, the mismatch of holes in the field connections on ordinary bolts must be checked with a gauge whose diameter is 1.5 mm less than the design hole diameter. The gauge must pass through at least 75% of the holes in each group. In the event that the gauge passes through less than 75% of the holes of each group, a second control assembly is made from other elements of this design. If in this case the coincidence of the holes turns out to be unsatisfactory, then a decision should be made by the technical management of the manufacturer and the design organization on how to correct the holes in the assembled elements, as well as in the structural elements of the entire batch, and on the advisability of further control assemblies.

13.4 Misalignment of holes in field connections on high-strength bolts with adjustable tension, as well as in flange connections, should be checked with a gauge, the diameter of which is 0.5 mm larger than the nominal diameter of the bolt. The gauge must pass through 100% of the holes in each joint. The control procedure is carried out according to 13.3.

13.5 The elements that have passed the control assembly must have assembly and fixing devices in the assemblies provided for by the design documentation.

13.6 The general assembly of structures, including oversized spatial ones, for block mounting is carried out if this requirement is in the design documentation agreed with the customer and the installation organization.

The general assembly of structures, as a rule, is carried out by the assembly organization at the construction site, component base or in other places specified by the customer.

It is allowed, with the consent of the customer, to carry out a general assembly at the manufacturer.

The overall assembly of structures should ensure complete assembly constituent elements design and geometric dimensions of it as a whole.

13.7 Structural elements that have passed the general assembly must have clamps for pre-assembly during installation, fitted edges of the elements for butt welding, drilled holes to the full diameter for mounting bolted connections and parts necessary for lifting and mounting structures.

14 Corrosion protection

14.1 Structures made of carbon and low alloy steels, depending on their purpose and operating conditions, should be protected from corrosion in accordance with the requirements of SNiP 2.03.11-85 and this SP in the following ways:

Painting with paints and varnishes;

Hot dip galvanizing or hot aluminizing by hot dip methods;

The same, followed by painting with paints and varnishes;

Thermal spraying of zinc or aluminum coating;

The same, followed by painting with paints and varnishes.

14.2 The protection system, grades of materials, the number of layers, the thickness of each layer and the total thickness of the coating for each specific object is regulated by the design documentation, SNiP 2.03.11-85, standards, this SP and other documentation for anti-corrosion protection and materials.

The main method of anticorrosive protection of structures, carried out by the enterprise, is painting with paints and varnishes. Other methods of protection must be agreed with the manufacturer.

14.3 Painting with paints and varnishes

14.3.1 The technological process of obtaining paint and varnish coatings consists in the sequential execution of the following operations: surface preparation, application of primer layers, drying of each primer layer, application of the required number of layers of coating material, drying of each coating layer.

14.3.2 In accordance with the requirements of GOST 9.402 and GOST 9.105, all operations for surface preparation and obtaining paint and varnish coatings should be carried out indoors at a temperature of at least +15 °C and relative air humidity of not more than 80%.

In technically justified cases, it is allowed, subject to the provision of the required quality of protective coatings, to perform surface preparation and painting at lower temperatures, but not lower than +5 °C.

14.3.3 The duration of the break between surface preparation and painting should not exceed 24 hours. When storing structures and blanks in the open air, the interval between surface preparation and painting should not exceed 6 hours.

14.4 Surface preparation before painting

14.4.1 Surface preparation before applying paint coatings should include the following operations:

Cleaning of welds from splashes of molten metal, flux residues, slag;

Removing burrs and sharp edges:

Before mechanical cleaning, degreasing of oily metal surfaces;

Mechanical cleaning of the surface from rust and scale;

Dedusting by blowing with compressed air (or industrial vacuum cleaners);

Degreasing.

14.4.2 When preparing the surface for painting, it is necessary to ensure the degree of cleaning of the surface of structures from scale and rust established by GOST 9.402 and SNiP 2.03.11-85 for various operating conditions according to the degree of aggressiveness.

14.4.3 The choice of the method of cleaning from scale and rust must be made depending on the required degree of cleaning according to table 11.

Table 11

14.4.4 When using primers-modifiers of rust type EP-0199 (TU 6-102084-86) and other similar materials as a primer layer, it is permissible to reduce the requirements for surface preparation in accordance with the standards and specifications for the materials used.

14.4.5 Mechanical preparation of the surface of structures with galvanized or aluminum coatings obtained by thermal spraying or hot method by immersion in a melt is not performed before applying paints and varnishes.

14.4.6 Before applying paint coatings, the surface of structures must be degreased. The degree of degreasing must correspond to the second in accordance with GOST 9.402. Degreasing should be done with brushes moistened with white spirit, solvent or solvent "Nefras" H 150/180 or wiping material that does not leave fibers on the surface of the structures.

Degreasing of structures production lines that have surface preparation units should be produced with ready-to-use aqueous alkaline solutions in accordance with the technological regulations and current RTDs.

14.4.7 The surface of structures with zinc or aluminum coatings must be cleaned of grease and other contaminants before painting. They should be removed with a wiping material moistened with white spirit that does not leave fibers on the surface. Coloring can be done only after the solvent has evaporated.

If the application of metal coatings is carried out by the manufacturer of structures, then, in order to avoid contamination of the surface of the resulting coating, painting should be done immediately after its application.

14.5 Paint application

14.5.1 Paints and varnishes must be applied in the following technological sequence: application of primers, drying of primers, application of top coats and drying of each top coat.

14.5.2 Paints and varnishes should be applied to structures and blanks by one of the following methods: pneumatic or airless spraying, jet pouring, spraying in an electric field, dipping, brushing.

The method of applying paints and varnishes should be established in accordance with GOST 9.105, depending on the type of paintwork material used, dimensions and configuration of structures.

14.5.3 Technological modes of application of paints and varnishes are set in accordance with the standards, specifications and other NTD for the material used.

14.5.4 In accordance with the requirements of GOST 9.402 (change No. 2, entered into force on 07/01/1988, Appendix 11) for surfaces cleaned of scale and rust by abrasive blasting (sand or shot blasting), the minimum allowable thickness of the paintwork coating must be at least 80 microns.

14.6 Drying of paint and varnish coatings should be carried out in accordance with the requirements of the standard, specifications or other documentation for the material.

14.7 Acceptance rules and control methods

14.7.1 When performing anti-corrosion protection of structures, it is necessary to perform quality control:

surface preparation;

paintwork materials;

Protective coatings.

14.7.2 The quality of the prepared surface before applying paints and varnishes must be controlled by the degree of purification from oxides and the degree of degreasing by the methods provided for by GOST 9.402.

14.7.3 Quality control of paints and varnishes should be carried out by the methods provided for by the relevant standards and specifications.

Paintwork materials in all respects must meet the requirements of standards and specifications.

14.7.4 The correct choice of solvents, working viscosities, methods and parameters of application, as well as drying modes of paints and varnishes during the technological process of painting structures should be controlled in accordance with the requirements of the technological regulations, standards and specifications for materials.

14.7.5 The quality of paint coatings must be controlled in terms of appearance, thickness, continuity and adhesion.

14.7.6 Quality appearance coatings should be controlled by visual inspection with the naked eye in natural or artificial diffused lighting of 100% of the structures. The coating must not have gaps, bubbles, cracks, chips, craters and other defects that affect the protective properties, and in appearance must comply with the requirements of GOST 9.032.

14.7.7 The continuity of the coatings must be controlled with an LKD-1M flaw detector.

14.7.8 The coating thickness should be controlled with a magnetic thickness gauge type MT-41 NTs (TU 25-06.2500-82) with a measurement range of 0 - 12 mm and an error of 5%.

14.7.9 The adhesion of the coating is checked by the method of lattice cuts according to GOST 15140 on control samples painted in the same flow with the structures. Coating adhesion should be no more than 2 points according to GOST 15140.

15 Marking of structures, transportation, acceptance of structures and rules for issuing accompanying documentation

15.1 Marking of structures, transportation, acceptance of structures and the rules for issuing accompanying documentation are carried out in accordance with the requirements of GOST 23118.

16 Additional requirements for the manufacture of structures with bolted field connections

16.1 These additional requirements include the following types of bolted connections:

Friction or shear-resistant connections, in which the acting forces are transmitted through friction that occurs along the contacting planes of the elements to be connected from the tension of high-strength bolts;

Shear or connections without controlled tension of the bolts, in which the acting forces are transmitted through the resistance of the bolts to shear and the elements to be connected to collapse;

Friction-shear, in which the acting forces are transmitted through joint work friction forces, shearing of bolts and crushing of connected elements;

Flanged connections on high-strength bolts with controlled tension, transmitting tensile, compression, bending, shear forces or their combined action.

16.2 Steel building structures (SSC) should be manufactured in accordance with the main sections of the joint venture and these additional requirements.

16.3 In accordance with the terms of the contract, the manufacturer completes the SSC with fasteners (hardware) of the following types:

Shear connections with bolts of nominal diameters 16, 20, 24 mm according to GOST 1759.1 (ST SEV 2651-80) strength classes 5.8, 8.8, 10.9 according to GOST 1759.0 (ST SEV 4203-83), GOST 1759.4 (ISO 898/1-78); nuts in accordance with GOST 1759.5 for bolts of strength classes 5.8, 8.8, 10.9, respectively, strength classes 5, 8 and 10; washers according to GOST 18123.

Friction and friction-shear - high-strength bolts with nominal diameters of 20, 24, 27 mm according to GOST 22353, nuts according to GOST 22354, washers according to GOST 22355, GOST 22356.

16.4 If the joined elements of welded sections, rolled profiles have different thicknesses or the height difference of rolled I-beams is more than 3 mm, the design gap must be filled with a gasket, the total thickness of which must be a multiple of 1 mm. Gaskets can be made from steel with a yield strength of 235 MPa by guillotine cutting, and the formation of holes by punching. The diameter of the gasket holes must be 5 mm larger than the nominal diameter of the bolt.

16.5 For friction and friction-shear joints, linings exceeding the following thicknesses for bolts should not be used: M20 - 20 mm, M24 - 30 mm, M27 - 40 mm.

If it is necessary to use pads of greater thickness, bolts of a larger diameter should be used or the pads should be made in two layers.

16.6 Joints should not be used, the total thickness of the connected elements of which exceeds the following values ​​for bolts: M20 - 60 mm, M24 - 100 mm, M27 - 140 mm.

In the case when the thickness of the connected elements exceeds 140 mm, bolts of large diameters should be used.

16.7 If it is necessary to use bolts with diameters less than 20 mm or more than 27 mm, design solutions should be agreed with the manufacturer.

16.8 The quality of rolled sheets for flanges (internal layers, coarse slag inclusions, etc.) must meet the requirements specified in Table 12. Quality control of steel by ultrasonic flaw detection is carried out by the SSC manufacturer.

Table 12

Notes

1 Defects, the distance between the edges of which is less than the length of the minimum of them, are evaluated as one defect.

2 At the discretion of the manufacturer, flaw detection testing of materials can be performed only after they have been welded to structural elements.

16.9 For flange connections (FS), high-strength bolts M20, M24 and M27 made of steel 40X "Select" of climatic modification KhL with a temporary resistance of at least 110 MPa (1100 kgf / cm 2), as well as high-strength nuts and washers for them in accordance with GOST 22353 - GOST 22356.

It is possible to use high-strength bolts, nuts and washers to them from steel of other grades. The geometric and mechanical characteristics of such bolts must meet the requirements of GOST 22353, GOST 22356 for bolts of the KhL version; nuts and washers - GOST 22354 - GOST 22356. The use of such hardware in the FS of each specific object must be agreed with the design organization-developer.

For FS elements of the SSC, high-strength bolts with a diameter of 24 mm (M24) should be used; the use of M20 and M27 bolts should be allowed in cases where the installation of M24 bolts is impossible or irrational.

16.10 In the manufacture of FS, as a rule, the following combinations of bolt diameters and flange thicknesses should be used:

16.11 Welds of the flange with the profile to be attached should be filleted without cutting the edges.

The height of the leg of the welded seams must be at least the thickness of the attached profile.

16.12 If the load-bearing capacity of the welds connecting the profile to the flange is not sufficient to transfer external force effects or it is necessary to increase the load-bearing capacity of the stretched sections of the FS without increasing the number of bolts or the thickness of the flanges, the latter should be reinforced with stiffeners.

The thickness of the stiffeners must not exceed 1.2 of the thickness of the main profile elements, and their length must be at least 200 mm. The stiffeners should be located so that the stress concentration in the section of the main profiles is minimal.

16.13 In the manufacture of SSC with FS, the following requirements should be met:

The non-perpendicularity of the ends of the parts attached to the flange should not exceed 0.002;

The assembly of structural elements with FS should be performed only in conductors. In the conductor, the flange should be fixed and fastened to the base surface with at least two plugs and two assembly bolts. The base surfaces of the conductors must be milled. In this case, the deviation of the tangent of the angle from the design value should not exceed 0.0007 in each of the two planes;

After welding, the outer surfaces of the flanges must be milled. The thickness of the flanges after milling must not be less than that specified in the project documentation.

16.14 The accuracy of the manufacture of structural elements with FS should be checked by a control assembly. The frequency of control assemblies is established by the manufacturer, but their volume must be at least 10% of the total number of structural elements with FS.

SSC with FS must meet the following requirements:

The tangent of the deviation angle of the flange surface should not exceed 0.0007 in each of the two planes;

The maximum deviation of the length of the element with FS should be 0; -5 mm;

A probe 0.1 mm thick should not penetrate into a zone with a radius of 40 mm from the bolt axis after tightening all the bolts of the connection to the design force.

16.15 SSK with bolted connections are painted completely. The contact surfaces of flanges, as well as friction and friction-shear connections, are not painted.

17 Additional requirements for the manufacture of coatings for industrial buildings from light metal structures

17.1 Coatings using spatial structures made of pipes, closed bent-welded profiles and building structures using frames must be made in accordance with the requirements of sections 1 - 15 of this SP and additional requirements set forth in 17.2 - 17.4.

17.2 Coatings with spatial lattice structures made of pipes.

17.2.1 The spatial lattice structure is a slab of the configuration and dimensions specified by the project with an orthogonal grid of the upper and lower chords with a cell |×|. The nodes of the upper and lower chords are connected by braces. The rod consists of an electric-welded pipe with washers welded into the ends. The rods of special bolts with nuts of increased height screwed onto them are passed into the holes of the washers. The rods are connected by means of the so-called convectors - a kind of spatial gussets in the form of polyhedrons cut in half or whole, in which there are threaded holes. Nuts act as locking elements that transmit compressive forces from the assembly to the rod. To ensure the operability of the structure, it is necessary to tightly touch the nodal elements (convectors) and nuts in all nodes of the system.

17.2.2 Parts included in nodal connections must meet the following requirements:

Forgings of key elements and bushings must comply with the 4th group according to GOST 8479;

The mechanical properties of forgings of key elements must comply with the strength category KP315, forgings of bushings - KP245 according to GOST 8479;

Size tolerances, shape deviations, allowances, forging overlaps and rounding radii of the outer corners of forgings - according to GOST 7505;

The treated surfaces of the parts must not have burrs, scuffs, nicks and other mechanical damage; sharp edges must be blunted;

Metric thread must be made in accordance with the requirements of GOST 9150 and GOST 24705; tolerance fields - according to GOST 16093 for bolts 8g, for nuts - 7H; thread exit, runaways, undercuts, grooves and chamfers - according to GOST 10549;

The manufacture and heat treatment of special bolts must be carried out in accordance with TU 36.25.12-60-91;

Electroplating (galvanizing) of key elements, couplings and bolts must be carried out in accordance with the requirements of GOST 9.303, the thickness of the galvanizing layer is 20 microns, followed by passivation;

As an anti-corrosion protection, it is allowed to use aluminizing the surfaces of structural plate elements, including nodal elements and bolts.

17.2.3 Bar element length L 0 (distance between bearing surfaces of nuts) must correspond to the design one. The tolerance value is set depending on the length of the element within ±1/1000. L 0 ≤ 3 mm rounded to 1 mm.

17.2.4 The geometrical dimensions of the fully assembled structural slab shall conform to the following dimensions:

The length of the sides of the plate L ± 1/1000. L≤ 20mm;

Diagonal length difference should not exceed 1/750 L≤ 30mm;

Height h± 1/1000. h≤ 3 mm.

17.2.5 Acceptance of structures is carried out in accordance with the requirements of the main sections of the joint venture, taking into account the following additional requirements:

Upon acceptance of each fiftieth set, a control assembly of at least 0.25 parts of the slab should be carried out;

The assembled fragment must meet the requirements of 17.2.4 of this SP.

17.3 Coatings using closed bent welded profiles

17.3.1 Coatings using closed bent-welded profiles are used, as a rule, for buildings with spans of 18, 24, 30 m with a column spacing of 12 m. Coatings consist of a system of roof and sub-rafter trusses.

Coatings are used in purlin and non-purlin versions with light enclosing structures.

17.3.2 Details of truss elements should be made on cutting machines. Gas cutting of profiles with an allowance and subsequent machining of the ends is allowed.

17.3.3 Truss assembly should, as a rule, be carried out in rigid jigs with strict fixation of the spatial position of the flanges of the joints of the truss chords and support ribs on bolts and plugs. In this case, milling of the truss flange connections is not required, provided that the requirements of Section 16 of this SP are met.

17.3.4 When assembling trusses by marking after welding, the flange connections of the upper and lower chords must be milled from one installation.

17.3.5 After assembly and welding, the truss assembly units must meet the requirements of Table 13.

17.3.6 It is necessary to include in the composition of one batch assembly units of trusses assembled on the same conductor.

17.3.7 When carrying out control assemblies, deviations in geometric dimensions should not exceed the values ​​given in Table 13.

17.4 Framed buildings

17.4.1 This appendix regulates the rules for the manufacture and acceptance of frame structures with a span of up to 36 m inclusive.

17.4.2 Assembly units of frames, as a rule, must be assembled in rigid jigs with strict fixation of flanges on bolts and plugs. When assembling frame elements according to marking or copier, frame flanges must be milled and meet the requirements of Section 16 of this SP.

17.4.3 The accuracy of frame manufacturing is established by carrying out control assemblies, while controlling the following quantities:

The geometric dimensions of the frame as a whole;

Density of contact of flange connections.

17.4.4 Deviations of the geometric dimensions of the frame along the outer edges of the elements during control assemblies should not exceed the following values:

Rack height H- ±1/1000 H≤ 10 mm;

span L- ±1/1000 L≤ 25mm;

Arrow for lifting the upper belt of the frame - no more than +30 mm and no less than - 5 mm;

Diagonal length difference - 1/1000 L≤ 30 mm.

17.5 The tightness of contact of flange joints is determined when all bolts are tightened to the design force in accordance with 16.25 of this SP.

Table 13

18 Additional rules for the construction of overhead power line towers and outdoor substation switchgear

18.1 These additional rules should be observed in the manufacture of steel structures of overhead power transmission lines (VL) and outdoor switchgears of substations (OSG) with a voltage of over 1000 V.

In the manufacture of special supports for overhead lines, along with this section, the requirements of the project should be followed.

18.2 The nominal hole diameters for shear bolts shall be 1 mm greater than the nominal diameter of the bolt shank.

Hole diameter deviations must be within: 0; +0.6 mm. The diameters of punched holes on the side of the matrix must not exceed the nominal diameter of the hole by more than 0.1 of the element thickness, but not more than by 1.5 mm.

When the design distance from the axis of the hole to the edge of the element along the force is less than 1.5 of the hole diameter, holes should be formed only by drilling.

18.3 Holes for bolts should be formed by punching, drilling or punching to a smaller diameter, followed by reaming to the design diameter in accordance with the instructions in the project documentation. Hole punching to the design diameter is acceptable in the following cases:

For structures operated in areas with a design temperature of minus 40 ° C and above - in elements made of steels with a yield strength of up to 275 MPa with a thickness of up to 20 mm inclusive and up to 16 mm inclusive in elements of steels with a yield strength of up to 375 MPa;

For structures operated in areas with a design temperature below minus 40 ° C - in elements made of steels with a yield strength of up to 275 MPa, up to 12 mm thick inclusive and up to 10 mm inclusive in elements of steels with a yield strength of up to 375 MPa.

18.4 The formation of holes by punching through the full diameter should be carried out in compliance with the following requirements:

The wear of the stamp and matrix in diameter is not allowed more than ± 0.3 mm;

Both on the side of the stamp and on the side of the matrix, the hole must have a regular round shape;

On the inner surface of the metal along the contour of the hole there should be no tears and delaminations of the metal; burrs along the contour of the holes on the die side must be removed.

18.5 The length of the cut from the center of the hole in elements having one hole for permanent bolts at the ends must not have deviations exceeding ± 1.5 mm.

18.6 Permissible dimensional deviations between holes shall not exceed:

- ±0.7 mm between adjacent holes in individual elements;

- ±1.0 mm between the centers of groups of holes (for joints with other elements);

- ±1.0 mm shift of groups of holes for joints of chords in adjacent chords of welded sections along the axis of the sections.

18.7 Manufacture of support structures should be carried out according to conductors and devices that ensure the interchangeability of elements, as well as the coincidence of holes in field connections.

18.8 The control assembly must be subjected to one out of every fifty manufactured supports and at least one from each batch of less than 50 pcs. It is permissible to make a control assembly of one support from a batch of more than 60 pcs. in the event that the elements of the supports are made on the same technological equipment without readjustment. Each first support made according to new or repaired conductors is also subject to control assembly.

18.9 Elements of supports in the amount of 2% of the lot are subject to verification for compliance with their length, distance between the extreme holes, and also the size between the centers of adjacent holes with the design dimensions.

18.10 Corrosion protection of the support elements of overhead lines and switchgear should be carried out in the form of hot-dip galvanizing in accordance with the requirements of Section 19 of this SP or paintwork in accordance with the requirements of Section 14 of this SP. The type of protection is established in the project documentation or in the contract.

19 Additional rules for anti-corrosion protection of hot-dip galvanized structures

19.1 Hot-dip galvanizing should be applied to structures operated in aggressive environments or having a long service life without periodic restoration of protective coatings.

19.2 Surfaces of structures to be hot dip galvanized shall be etched or shot blasted or shot peened with cast iron shot.

19.3 The thickness of the zinc coating depends on the thickness of the metal, the silicon content of the steel, the soak time in the bath and the temperature of the bath.

19.4 The specified coating thickness for a particular structure should be achieved by varying the soak time of the structure in the bath (within a wide range) and the temperature of the bath (within a narrow range).

19.5 In order to prevent the formation of cracks in zinc coatings during operation, its thickness should not exceed 250 microns.

If the design solution and the steel grades used do not allow obtaining a coating of 250 microns or less by varying the technological process, the surfaces of the structures to be galvanized must be treated with crushed cast iron shot.

19.6 The change in the thickness of the zinc coating for a metal thickness of 6 mm or more, depending on the silicon content and the exposure time at a bath temperature of 480 ° C, is given in Table 14 (reference data).

Table 14

Table 15

19.8 The minimum and maximum thickness of the zinc coating should be determined by weighing control samples to be galvanized together with the structures or by using a magnetic thickness gauge.

To determine the minimum thickness of the zinc coating, a sample should be selected from the smallest thickness of rolled metal used in the structure or from steels with a silicon content of less than 0.07% or in the range from 0.12 to 0.2%.

To determine the maximum thickness of the zinc coating, a sample should be selected from the largest thickness used in the design or with an unfavorable silicon content in the range from 0.05 to 0.12% or more than 0.2%.

The dependence of the average coating thickness on the difference in masses of control samples before and after galvanizing in terms of g/m 2 is shown in Table 16. The number of control samples must be established by the manufacturer.

Table 16

19.9 When hot-dip galvanizing on the surface of structures, the following are allowed: small grains of hard zinc (with a diameter of not more than 2 mm), small zinc deposits that do not interfere with the connection of elements at the mating points, as well as matte spots, gray tone, small areas of tint in the absence of damage to the zinc coating, uneven surface caused during warehousing and storage, porosity, slight white (white rust) or dark zinc corrosion products.

19.10 Small parts, as well as parts with threaded connections, galvanized in baskets to obtain a uniform coating and improve appearance, should be centrifuged.

19.11 Design documentation shall provide for special design solutions, taking into account the specifics of hot-dip galvanizing, in order to prevent structural deformations and destruction of welds.

19.12 When galvanizing hardware and parts with threaded connections, the external thread should be cut with a minus tolerance by the amount of the zinc layer, and the internal thread - after galvanizing.

19.13 In order to replace pickling with shot blasting in surface preparation, solutions should be used in the design of structures that do not have cracks and bottlenecks that are not accessible for shot blasting.

19.14 Electric welding of galvanized structures using a special technology is allowed, followed by cleaning and painting of the welding zones with zinc-rich silicate paints and varnishes.

19.15 Galvanized structures intended for operation in the ground must be additionally coated with thick bitumen-based materials.

19.16 If long-term operation of galvanized structures in aggressive environments is necessary, they must be additionally painted.

19.17 Dimensions of structures to be hot-dipped galvanized shall be agreed with the manufacturer and shall correspond to the dimensions of pickling and galvanizing baths.

Annex A

The values ​​of the main indicators of the mechanical properties of steel, recommended for calculating the modes of machining of parts

Appendix A. Values ​​of the main indicators of the mechanical properties of steel, recommended for calculating the modes of machining of parts

Code of Practice for Design and Construction
SP 53-101-98
"Production and quality control of steel building structures"
(approved by the Decree of the Gosstroy of the Russian Federation of May 17, 1999 N 37)

Production and quality control of steel structures

1 area of ​​use

The joint venture does not apply to steel structures:

Railway and road bridges;

Reservoirs and gas holders;

Cases of blast furnaces and cowpers;

Hydraulic structures.

For approval during the development of design and technological documentation;

To control the quality of manufacturing steel structures.

3 General

3.1 The manufacture of steel building structures (hereinafter referred to as SSC) is carried out by enterprises and organizations that have state licenses of the Russian Federation, giving the right to manufacture structures of the corresponding groups according to the classification adopted in SNiP II-23-81 *.

3.2 General requirements for the design and manufacture of SSC are set out in the SP in accordance with the requirements of SNiP II-23-81*.

3.3 To launch the production of structures, the manufacturer, on the basis of design documentation, develops technological documentation, the form and volume of which depend on the specifics of production and the complexity of the products.

For unique structures, special technical requirements are developed.

4 Acceptance of design documentation, incoming inspection and storage of rolled metal products, welding and paintwork materials, fasteners

4.1 All design documentation incoming to the enterprise must be reviewed and analyzed in order to:

Error detection;

Checking the assembly of structures (for typical objects);

Project manufacturability assessments;

Evaluation of the economic feasibility of manufacturing structures in a specific production environment;

Coordination of changes in steel grades, design solutions for units and types of connections.

With a positive result of checking the design documentation, the technical manager of the enterprise makes a decision to transfer the object to production. For complex and unique objects, the decision is made at the technical council of the enterprise.

Rolled metal products (rolled products), welding, paint and varnish materials and fasteners arriving at the enterprises from suppliers, upon acceptance, must be checked by the technical control service of the enterprise in terms of quantity, completeness and compliance with standards, specifications (TU), supply contracts, work orders.

4.2 The type and plan of input control is established by the technical services of the enterprise, if necessary, in agreement with the supplier.

4.3 An acceptance certificate must be drawn up for each accepted rolled metal car, type of rolled metal, steel grade, melt.

4.3.1 Upon acceptance of rental, the following should be checked:

Quantity by theoretical weight, assortment and grades of steels according to work orders, stamps or tags of the supplier enterprise;

The absence of delaminations, cracks, shells, sunsets, dents and general deformations that are visible in the rental, exceeding those allowed by the relevant standards and specifications.

4.3.3 After acceptance, additional marking of rolled products is carried out: the number of the acceptance certificate is applied with white paint and the steel grade is applied in color in accordance with the system adopted at the enterprise.

4.3.4 At the metal warehouse, computer, card-index or journal accounting of the movement of rolled products should be kept according to its arrival and consumption. Accounting should be kept for each profile of rolled products, taking into account the steel grade and the number of the acceptance certificate.

4.4 When accepting welding and paintwork materials, fasteners, the following rules must be observed.

4.4.1 Check the availability of an accompanying document, which should indicate the name of the material, batch number and indicators certifying the compliance of the material with the requirements of regulatory and technical documentation (NTD).

4.4.2 Determine the integrity of the packaging by external inspection.

4.4.3 Determine the amount of materials by weighing, piece counting, theoretically.

4.4.4 The results of acceptance are drawn up by an acceptance certificate and included in the general system of movement of materials at the enterprise.

4.4.5 If necessary, apply the acceptance certificate number on the container with paint, and the expiration date on the container of paints and varnishes.

4.5 Rolled products must be stored in a warehouse sorted by profiles and steel grades.

Rolled products should be stored indoors, equipped with special devices that provide mechanization of intra-warehouse operations.

Rolled steel should be stored in racks with dividing racks, and rolled sheets - in specially equipped places, serviced by cranes with magnetic washers.

Coils should be stored vertically or on special pallets in a horizontal position. Cranes serving coiled steel warehouses must be equipped with special grippers.

Rolled products should be stored in equipped mechanized warehouses in accordance with the design and technological documentation for this warehouse and the instructions developed by the enterprise.

It is possible to carry out temporary storage (within 3 months from the date of shipment by the manufacturer) of profiled steel in specially equipped racks in the open air.

4.6 Welding consumables (welding wire, electrodes, flux, flux-cored wire) should be stored separately by brands and batches in a warm and dry room in their original packaging or special containers.

4.7 Paints and varnishes should be stored in original containers in specially equipped rooms that ensure fire safety and environmental protection.

4.8. Fasteners (bolts, nuts, washers) should be stored in original or special containers indoors. With a long period of storage, if necessary, it is necessary to restore the conservation protective coatings.

5 Preparation of rolled metal products, welding and paintwork materials before submission to production

5.1 Before being put into production, rolled products must be checked for compliance with the accompanying documentation, cleaned from moisture, snow, ice, oil and other contaminants.

5.2 Straightening of rolled products, depending on the profile, should be carried out on sheet straightening and sorting machines and presses in a cold state.

The maximum allowable values ​​of deflections after cold straightening are given in table 1.

5.3 It is permissible to straighten steel by local heating with a flame of gas burners, while the temperature of the heating zone should not exceed 800 ° C for hot-rolled and normalized steels, and 700 ° C for thermally improved steels.

5.4. After straightening, the rolled products must meet the following requirements:

5.4.1 Have no cracks or delaminations. It is allowed to have local dents in the thickness and width of rolled products to a depth not exceeding twice the minus tolerance for this type of rolled products, provided for by the relevant GOST or TU, but in all cases not more than 1 mm in thickness and 3 mm in cross-sectional dimensions.

5.4.2 The discrepancy between the plane of sections of profiled products should not exceed the appropriate tolerances established by GOST or TU for this type of rental.

5.4.3. Limit deflections of profiled steel along the entire length of the element should not exceed mm, and deflections of local curvature - 1 mm over a length of 1.0 m.

5.4.4 The flatness of rolled sheets must comply with GOST 19903.

5.5 Welding consumables are delivered to the workplace marked in the amount necessary for work during the day.

5.5.1 Welding wire must be cleaned from rust, grease and other contaminants to a metallic sheen (except for copper-plated wire), wound into coils, cassettes or wound on coils.

5.5.2 Electrodes and fluxes must be calcined in accordance with the modes specified in GOST or TU and passports for this type of welding material.

5.5.3 Cored wire must be cleaned, annealed and rewound into coils, cassettes or spools.

5.6 Before use, paints and varnishes must be brought to the parameters established by the technological regulations and NTD for a specific material.

Preparation of paints and varnishes for use consists of mixing operations until a homogeneous consistency is obtained without sediment at the bottom of the container, introducing, if necessary, the required amount of hardeners, driers and other additives, diluting to a working viscosity and filtering.

5.7 All operations for the preparation of paints and varnishes should be performed in the paint preparation department.

The temperature of the paintwork material must be equal to the air temperature in the paint preparation department, for which the materials from the warehouse must arrive no later than a day before their use. The temperature in the paint preparation department must be at least +15°С.

5.8 Dilution of paints and varnishes to working viscosity must be carried out with solvents in accordance with the NTD for a specific material and the requirements of the technological regulations.

5.10 Submission to workplaces prepared for use of paints and varnishes should be made in a closed container. When consuming more than 200 kg (of one item) per shift, it is advisable to supply paintwork materials centrally through pipes.

6 Marking, basting, making templates and conductors

6.1 Marking on rolled metal and making templates should be carried out using metal rulers and tape measures that correspond to the accuracy of the second class according to GOST 7502 and GOST 427, calipers according to GOST 166, gage gauges according to GOST 164, calibration squares according to GOST 3749, goniometers with vernier according to GOST 5378.

6.2 When marking on rolled metal and making templates, it is necessary to take into account machining allowances and welding shrinkage in accordance with the recommendations in Table 2.

table 2

SP 53-101-98

UDC 69 (083.74):093.8

System normative documents in construction

CODE OF RULES FOR DESIGN AND CONSTRUCTION

MANUFACTURING AND QUALITY CONTROL OF STEEL BUILDING STRUCTURES

Introduction date 1999-01-01

FOREWORD

1 DEVELOPED by JSC Concern "Stalkonstruktsiya" and NIPIPromstalkonstruktsiya with the participation of TsNIIProektlegkonstruktsiya, NPP Energostroyprom, TsNIIproektstalkonstruktsiya named after A.I. Melnikov, South Ural State University and OJSC "Chelyabinsk ZMK"

2 INTRODUCED by JSC Concern "Stalkonstruktsiya"

3 APPROVED AND INTRODUCED BY Decree of the Gosstroy of Russia dated May 17, 1999 No. 37

4 DEVELOPED IN THE DEVELOPMENT OF GOST 23118

The set of rules was developed by:

Dr. tech. Sciences V.M. Baryshev, cand. tech. Sciences V.F. Belyaev, Dr. tech. Sciences R.G. Gubaidulin, cand. tech. Sciences D. V. Kulik, Dr. tech. Sciences V.V. Kalenov, cand. tech. Sciences D.M. Kramarenko, cand. tech. Sciences K.0. Lukyanov, A.N. Secrets, V.G. Stolovitsky, G.V. Teslya-Teslenko, cand. tech. Sciences A.K. Tingaev, Dr. tech. Sciences A.B. Pavlov, V.B. Yakubovsky

1 AREA OF USE

This Code of Rules (hereinafter referred to as the SP) contains general provisions for the prefabrication and quality control of steel building structures (buy rolled metal in Moscow) of buildings and structures for industrial, public and residential purposes.

The joint venture does not apply to steel structures:

– railway and road bridges;

– reservoirs and gas holders;

– buildings of blast furnaces and cowpers;

- hydraulic structures.

– for approval during the development of design and technological documentation;

– to control the quality of steel structures manufacturing.

3 GENERAL

3.1 The manufacture of steel building structures (hereinafter - SSC) is carried out by enterprises and organizations that have state licenses of the Russian Federation, giving the right to manufacture structures of the corresponding groups according to the classification adopted in SNiP II-23-81 *.

3.2 General requirements for the design and manufacture of SSC are set out in the joint venture in accordance with the requirements of SNiP II-23-81 *.

3.3 To launch the production of structures, the manufacturer, on the basis of design documentation, develops technological documentation, the form and volume of which depend on the specifics of production and the complexity of the products.

For unique structures, special technical requirements are developed.

4 ACCEPTANCE OF DESIGN DOCUMENTATION, INPUT CONTROL AND STORAGE OF METAL ROLL, WELDING AND PAINT MATERIALS, FASTENING PRODUCTS

4.1 All design documentation received by the enterprise must be reviewed and analyzed in order to:

– detection of errors;

- checking the assembly of structures (for typical objects);

- assessment of the manufacturability of the project;

- assessment of the economic feasibility of manufacturing structures in a specific production environment;

– coordination of changes in steel grades, design solutions for assemblies and types of connections.

With a positive result of checking the design documentation, the technical manager of the enterprise makes a decision to transfer the object to production. For complex and unique objects, the decision is made at the technical council of the enterprise.

Rolled metal products (rolled products), welding, paint and varnish materials and fasteners arriving at the enterprises from suppliers, upon acceptance, must be checked by the technical control service of the enterprise in terms of quantity, completeness and compliance with standards, specifications (TU), supply contracts, work orders.

4.2 The type and plan of input control are established by the technical services of the enterprise, if necessary, in agreement with the supplier.

4.3 An acceptance certificate must be drawn up for each accepted rolled metal car, type of rolled metal, steel grade, melt.

4.3.1 When accepting a rental, you should check:

- quantity by theoretical weight, assortment and grades of steels according to work orders, stamps or tags of the supplier enterprise;

– the absence of delaminations, cracks, shells, sunsets, dents and general deformations that are visible in the rental, exceeding those allowed by the relevant standards and specifications.

4.3.2 If there are deviations from the requirements of the standard or specifications, it is necessary to draw up a reclamation act.

4.3.3 After acceptance, additional marking of rolled products is carried out: the number of the acceptance certificate is applied with white paint and the steel grade is applied with color paint in accordance with the system adopted at the enterprise.

4.3.4 In the metal warehouse, computer, card-index or journal accounting of the movement of rolled products should be kept according to its arrival and consumption. Accounting should be kept for each profile of rolled products, taking into account the steel grade and the number of the acceptance certificate.

4.4 When accepting welding and paintwork materials, fasteners, the following rules must be observed.

4.4.1 Check the availability of an accompanying document, which should indicate the name of the material, batch number and indicators certifying the compliance of the material with the requirements of regulatory and technical documentation (NTD).

4.4.2 Determine the safety of the container by external inspection.

4.4.3 Determine the amount of materials by weighing, piece counting, theoretically.

4.4.4 The results of acceptance are drawn up by an acceptance certificate and included in the general system of movement of materials at the enterprise.

4.4.5 If necessary, apply the acceptance certificate number on the container with paint, and the expiration date on the container of paints and varnishes.

4.5 Rolled products must be stored in a warehouse sorted by profiles and steel grades.

Rolled products should be stored indoors, equipped with special devices that provide mechanization of intra-warehouse operations.

Rolled steel should be stored in racks with dividing racks, and rolled sheets - in specially equipped places, serviced by cranes with magnetic washers.

Coils should be stored vertically or on special pallets in a horizontal position. Cranes serving coiled steel warehouses must be equipped with special grippers.

Rolled products should be stored in equipped mechanized warehouses in accordance with the design and technological documentation for this warehouse and the instructions developed by the enterprise.

It is possible to carry out temporary storage (within 3 months from the date of shipment by the manufacturer) of profiled steel in specially equipped racks in the open air.

4.6 Welding consumables (welding wire, electrodes, flux, flux-cored wire) should be stored separately by brands and batches in a warm and dry room in their original packaging or special containers.

4.7 Paints and varnishes should be stored in their original containers in specially equipped rooms that ensure fire safety and environmental protection.

4.8 Fasteners (bolts, nuts, washers) should be stored in a factory or special container in a closed room. With a long period of storage, if necessary, it is necessary to restore the conservation protective coatings.

5 PREPARATION OF ROLLING METAL, WELDING AND PAINTING MATERIALS BEFORE SUBMISSION TO PRODUCTION

5.1 Before being put into production, rolled products must be checked for compliance with the accompanying documentation, cleaned from moisture, snow, ice, oil and other contaminants.

5.2 Straightening of rolled products, depending on the profile, should be carried out on sheet straighteners and grade straighteners and presses in a cold state.

The maximum allowable deflection values ​​after cold straightening are given in Table 1.

5.3 It is permissible to straighten steel by local heating with a flame of gas burners, while the temperature of the heating zone should not exceed 800 ° C for hot-rolled and normalized steels, and 700 ° C for thermally improved steels.

5.4 After straightening, the rolled products must meet the following requirements:

5.4.1 Have no cracks or splits. It is allowed to have local dents in the thickness and width of rolled products to a depth not exceeding twice the minus tolerance for this type of rolled products, provided for by the relevant GOST or TU, but in all cases not more than 1 mm in thickness and 3 mm in cross-sectional dimensions.

5.4.2 The discrepancy between the plane of sections of profiled products should not exceed the appropriate tolerances established by GOST or TU for this type of rental.

5.4.3 Limit deflections of profiled steel along the entire length of the element should not exceed 0.001 l£ 10 mm, and deflections of local curvature - 1 mm over a length of 1.0 m.

5.4.4 The flatness of sheet metal must comply with GOST 19903.

5.5 Welding materials are supplied to the workplace marked in the amount necessary for work during the day.

5.5.1 Welding wire must be cleaned of rust, grease and other contaminants to a metallic sheen (except for copper-plated wire), wound into coils, cassettes or wound on coils.