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FEDERAL AGENCY FOR TECHNICAL REGULATION AND METROLOGY

NATIONAL

STANDARD

RUSSIAN

FEDERATIONS

General specifications

Official edition

Foreword

1 DEVELOPED by the Open Joint-Stock Company Taganrog Boiler-Building Plant Krasny Kotelshchik (OJSC TKZ Krasny Kotelshchik) and the Open Joint-Stock Company Scientific and Production Association for Research and Design of Power Equipment. I.I. Polzunova (NPO CKTI OJSC)

2 INTRODUCED by the Technical Committee for Standardization TC 244 "Stationary power equipment"

3 APPROVED AND PUT INTO EFFECT by the Order of the Federal Agency for Technical Regulation and Metrology dated November 06, 2014 No. 1485-st

4 INTRODUCED FOR THE FIRST TIME

The rules for the application of this standard are established in GOST R 1.0-2012 (section 8). Information on changes to this standard is published in the annual (as of January 1 of the current year) information index "National Standards", and the official text of changes and amendments is published in the monthly information index "National Standards". In case of revision (replacement) or cancellation of this standard, the corresponding notice will be published in the next issue of the information index "National standards". Relevant information, notice and texts are also posted in the public information system - on the official website of the Federal Agency for Technical Regulation and Metrology on the Internet (gost.ru)

© Standartinform, 2015

This standard may not be reproduced in whole or in part, replicated and distributed as an official publication without permission from the Federal Agency for Technical Regulation and Metrology.

manufacturer with subsequent cleaning of the places of correction and control for the absence of cracks.

When grinding with an abrasive wheel, the stripping marks should be directed along the edges.

4.5.2.3 The edges and ends of parts after mechanical cutting should not have cracks; sharp edges and burrs should be blunted. Irregularities and burrs larger than 0.5 mm are not allowed, blockages should not exceed 1 mm.

4.5.3 Shock impacts on carbon and low-alloy steel, as well as cutting it with scissors, punching holes in it and other similar operations at temperatures below minus 25 ° C are not allowed.

4.6 Requirements for assembly and welding of steel structures

4.6.1 General basic requirements for assembly and welding of structures must comply with the requirements of GOST 5264, GOST 8713, GOST 14771, GOST 11534 and GOST 23518; special requirements for assembly and welding of steel structures of boilers must comply with the requirements of this standard.

4.6.2 Fitters and welders who have been trained and certified in accordance with the requirements of Rostekhnadzor and have the corresponding entries in the certificate for the right to perform these operations are allowed to perform work on the assembly and welding of steel structures of boilers. Before starting work on the manufacture of metal structures, the manufacturer is obliged to carry out certification of welding technologies in accordance with the requirements of Rostekhnadzor.

It is allowed to tack parts made of 12MX and 12XM steels without preheating if E50A electrodes are used for these purposes.

4.6.3 The minimum distance between the axes of adjacent butt welded joints of component parts, as a rule, should be at least 400 mm. The location areas and types of butt joints should be indicated in the drawings.

4.6.4 Joining of elements of composite sections, as a rule, should be done before general welding of the structure; in some cases, welding of such joints in the assembled assembly unit may be allowed with the permission of the author of the project.

4.6.5 Additional joining of elements of load-bearing welded structures, which is not provided for by the drawing, can be made only with the permission of the author of the project. The docking of secondary, mastered and frequently encountered in a given enterprise elements can be performed according to the manufacturer's documentation.

4.6.6 Welded joints of design elements of steel structures should be marked with the welder's personal stamp in a conspicuous place, at a distance of 20-40 mm from the seam. An assembly element welded by one welder is marked once. When welding elements by several welders, the seams are marked by each welder along the boundaries of his welding area. Weld seams subject to non-destructive testing are marked at the beginning and at the end of the seam, with the exception of seams up to 1 m long, which are marked once at the beginning or at the end of the seam.

4.6.7 Giving the fillet welds a concave profile with a smooth transition to the base metal, as well as making butt welds without reinforcement, if provided by the drawings, should be done, as a rule, with the appropriate selection of welding modes and the appropriate location of the parts to be welded. In necessary cases, it is allowed to process the seams with an abrasive wheel, or use another method of processing.

4.6.8 The beginning and end of the butt weld, as well as the fillet weld made by the automatic machine, should be brought out of the welded parts onto the lead-out strips, which should have a groove similar to the welded seam being performed, and installed in the same plane with the parts to be welded close to their edges. The accuracy of the installation of the lead plates is the same as when assembling elements for welding. At the end of welding, the lead-out strips are removed by mechanical or oxygen cutting with a thorough cleaning of the ends of the seams.

Note - If necessary, provided for by the technological documentation, it is allowed to use manual arc or mechanized welding for additional welding of welded seams made by automatic submerged arc welding.

4.6.9 Location, design and dimensions of seams must comply with GOST 5264, GOST 8713, GOST 14771, GOST 11534, GOST 23518, GOST 15164 and the design and technological documentation of the manufacturer.

4.6.10 The quality of the welds performed at the enterprise for welding and assembly devices, slinging parts, scaffold fastening parts and similar elements should be no lower than the quality of the main structure welds.

4.6.11 Welding work should be carried out, as a rule, at a positive ambient temperature.

If necessary, electric arc welding without preheating can be carried out at a negative outside air temperature, which should not be below that indicated in Table 5.

4.6.12 At an ambient temperature below that specified in Table 6, manual, semi-automatic and automatic welding of steel structures with a ultimate strength up to 540 MPa inclusive should be carried out with preheating. Heating is carried out over the entire thickness of the metal up to 120-180 ° C at a width of at least 100 mm on both sides of the joint and at a length of at least 300 mm on both sides of the seam boundaries (for open seams).

4.6.13 Welding of steel structures with ultimate strength over 540 to 590 MPa should be carried out at a temperature not lower than minus 15 ° С with a steel thickness of up to 16 mm and not lower than 0 ° С with a steel thickness of over 16 to 25 mm. At lower temperatures, welding of steel of the indicated thicknesses should be carried out with preheating to a temperature of 120-160 ° C.

For steel thicknesses over 25 mm, preheating must be carried out in all cases, regardless of the ambient temperature.

4.6.14 Mechanized submerged-arc welding of a structure is allowed to be performed without heating in the following cases:

from carbon steels:

up to 30 mm thick at a temperature not lower than minus 30 ° С;

at thicknesses over 30 mm at a temperature not lower than minus 20 ° С;

made of low alloy steel:

up to 30 mm thick at a temperature not lower than minus 20 ° С;

at thicknesses over 30 mm at a temperature not lower than minus 10 ° С;

4.6.15 Mechanized welding at temperatures below those specified in 4.6.14 should be performed only in modes that provide an increase in heat input and a decrease in the cooling rate.

4.6.16 At a steel temperature below minus 5 ° C, welding should be carried out from the beginning to the end of the seam without interruption, except for the time required to change the electrode or electrode wire and clean the seam at the place where welding is resumed.

It is not allowed to stop welding before the seam of the required size is made and to leave individual sections of the seam not welded. In case of forced termination of welding, the process should be resumed after heating the steel in accordance with the technological process developed for the welded structures.

4.6.17 Welding of structures made of heat-resistant steels, regardless of the ambient temperature, should be performed with preliminary and concurrent heating in accordance with the requirements of Table 6.

4.6.18 Welded butt joints made of heat-resistant steels are subject to heat treatment (tempering) in accordance with the requirements of Table 7.

The requirements of table 7 also apply to fillet and tee welds.

with the size of the seam leg:

for steels 12MX, 12XM, 15XM - more than 15 mm; for steel 12X1MF - more than 10 mm.

4.6.19 At the end of welding, all technological devices must be removed, followed by welding and cleaning of the tack welds, the welded seams of the structure must be cleaned of slag, splashes, and metal leaks. It is allowed not to clean metal splashes from surfaces that are not subject to painting during installation, difficult to access for external inspection, not affecting the presentation, as well as the surfaces of auxiliary elements used for packaging and transportation.

4.7 Requirements for the assembly of steel structures

4.7.1 The elements of the frame columns, assembled on installation, when transferring loads by tight contact, must be supplied with milled ends.

4.7.2 Only those elements and parts of steel structures that meet the requirements of this standard and are accepted by the Quality Control Department or a foreman should be allowed for assembly. The results of the control should be noted in a special journal or other relevant reporting documentation adopted at the enterprise.

4.7.3 The assembly should be carried out according to the drawings and technological documentation, providing for the necessary assembly accuracy and preservation of the geometric shape.

4.8 Test assembly requirements

4.8.1 The necessity and scope of the control assembly of products are determined by the working drawings for the metal structures of the boilers.

4.8.2 During control assembly of erection joints of columns, racks, beams, shields, trusses, it is allowed to shift the edges of the abutting elements up to 0.1 of their thickness, but not more than 2 mm, if there are no other instructions in the design documents.

The gap between the parts in the joints for which a tight fit is provided by the project should not exceed 0.5 mm. In this case, the stylus of this thickness should not pass between the beveled surfaces of the parts.

4.8.3 Control assembly of oversized products such as long-length shields, spatial sheet structures (bunkers, mines and other load-bearing elements) should be carried out in accordance with the requirements of design and technological documents.

This checks:

Coincidence of connecting and installation dimensions;

Compliance of dimensions and permissible deviations for assembly with the requirements of drawings and regulatory and technical documentation.

4.8.4 At the end of the control assembly, the relative position of the mating elements should be fixed by punching or drawing marks. All structures that have passed the control assembly must bear the OTK mark.

4.8.5 After the control assembly, an act must be drawn up in accordance with the form adopted at the manufacturer.

5 Requirements for holes for bolted connections

5.1 Nominal diameters of holes for bolted connections of various types and accuracy classes A, B and C in accordance with GOST 1759.0, as well as high-strength bolts in accordance with GOST R 52643 and GOST R 52644 are taken in accordance with the current regulatory documents 1 and working documentation.

5.2 Hole formation is carried out at the manufacturing plant by drilling or punching. Hole punching is not allowed in the design connections, as well as those specified in the working documentation.

5.3 Limit deviations of hole diameters from the design ones, depending on the method of formation and the type of bolted connection, are given in Table 8.

5.4 Control and general assembly of structures with mounting bolted connections should be carried out at the manufacturer, if it is stipulated in the working documentation.

6 Safety requirements

6.1 Requirements for safety and industrial sanitation when performing all work on the manufacture of steel structures and their parts must comply with the instructions of the manufacturer, developed in accordance with the requirements of GOST 12.2.003, GOST 12.3.002, GOST 12.3.003, GOST 12.3.004 , GOST 12.3.005, GOST 12.3.009, GOST R 53001, GOST 12.2.008 and the Rules of Gosgortekhnadzor of Russia.

6.2 Ventilation, air conditioning and air heating systems of industrial, warehouse and auxiliary buildings must comply with GOST 12.4.021 and provide meteorological conditions and air purity at permanent workplaces, in the working and serviced area, in accordance with sanitary standards and GOST 12.1.005.

6.3 Machine tools, machine tools and equipment must meet the requirements of GOST 12.2.009, GOST 12.2.029.

7 Completeness

7.1 The completeness of delivery of steel structures must comply with the requirements of the standard for general technical specifications for boilers.

7.2 The scope of delivery of steel structures shall include installation drawings and shipping documents.

8 Acceptance rules

8.1 Acceptance of steel structures, as well as operational control during their manufacture, should be carried out by the technical control department of the manufacturer in accordance with the requirements of design, technological and regulatory technical documentation, as well as this standard.

8.2 Rolled steel for steel structures of boilers at a steel structure manufacturer must undergo technical control before being put into production, including:

Visual control of accompanying documentation (certificates, passports);

Visual inspection of packaging and labeling;

External technical inspection and measuring control of rolled steel.

In this case, marking and sorting of rolled products should be carried out.

8.3 When controlling the accompanying documentation, the following is checked:

Availability of all data and technical characteristics of the rental;

Compliance of the technical data specified in the certificate with the requirements of the documentation for the supply of rolled products.

8.4 When checking packaging and labeling, the following is checked:

For rolled steel - compliance of packaging and labeling with the requirements of GOST 7566;

For fencing pipes - compliance with the requirements of GOST 13663.

8.5 When accepting finished products, the following is checked:

Completeness of steel structures for compliance with the requirements of design documentation;

Correct use of materials;

Compliance of the permissible deviations of the sizes of products with the requirements of technical documentation

Correctness of operational marking and branding of products (including 4.8.4 and control samples), as well as marking of finished products and transport marking;

The volume and quality of the control assembly;

Correctness of packaging, coloring and preservation, as well as the availability of shipping documentation.

In addition, upon acceptance of finished products, the following are carried out:

External technical inspection and measuring control;

Operational control of welded joints;

Control tests.

8.6 Each finished product must be marked with the OTK mark.

9 Control methods

9.1 The scope and methods of inspection of steel structures must comply with the requirements of this standard and technical documentation.

9.2 Methods of control of rolled steel supplied to the enterprise for the manufacture of steel structures and their parts, as well as control of packaging and marking of rolled steel must comply with the requirements of GOST 7566, GOST 380 and product mix standards.

9.3 During external technical inspection and measurement control, the dimensions, shape and surface quality of rolled steel, their compliance with the requirements of standards, specifications and this standard are checked.

9.4 Quality control of welded joints

9.4.1 Quality control of welded joints of steel structures should be carried out by the methods provided for by GOST 3242.

9.4.2 Methods for monitoring the mechanical properties of welded joints of steel structures should

9.4.3 The radiographic method for testing welded joints of steel structures must comply with the requirements of GOST 7512.

9.4.4 Methods of ultrasonic testing (UZD) of welded joints of steel structures must comply with the requirements of GOST 14782.

9.4.5 Sampling methods for determining the chemical composition of welded joints in steel structures must comply with the requirements of GOST 7122.

9.4.6 Quality control of welded joints to be checked shall be carried out after heat treatment of the product.

Note - Repeated inspection of butt welds is allowed not to be performed in the case of heat treatment and ultrasonic inspection of these welds before the final welding of the product.

9.4.7 The results of inspection of welded joints of design elements shall be recorded in the relevant documentation.

9.4.8 Welded joints are subject to visual inspection and measurement, regardless of the dimensions of the parts to be welded, the steel grade and the welding method.

Visual inspection checks:

1) compliance of the assembly and welding of steel structures with the requirements of 4.6.4-4.6.17, including the presence of the OTK mark of acceptance of the assembly for welding and the welder's mark;

2) compliance with the specified geometric dimensions; at the same time, the seams of critical design elements of steel structures are subject to continuous control, and the seams of secondary non-design elements - selective (in an amount of at least 20%);

3) surface quality of welded seams; in appearance, the seams should have: smooth surface (for automatic welding);

fine-flaked surface (with the height of the flakes within the tolerance for the dimensions of the weld according to the relevant standards);

without sagging - for other types of welding;

smooth transition to the base metal - for all types of welding;

4) in multilayer seams, the size of the depressions between two adjacent beads during welding in the lower position should not exceed:

for manual arc welding - 1 mm;

for automatic and semi-automatic welding in carbon dioxide environment, as well as for automatic submerged arc welding - 2 mm;

for welding in a different spatial position - respectively 2 and 3 mm without reducing the leg of the seam.

Before visual inspection, welded seams and the adjoining surface of the base metal at a width of 20 mm on both sides of the weld seam must be cleaned. Visual inspection should be carried out with sufficient illumination. Doubtful places should be viewed through a magnifying glass.

The method of visual inspection is established by the manufacturer's quality control department. Visual inspection must precede all other controls.

9.4.9 Testing of seams ensuring the tightness (tightness) of the structure: sheathing boards of bunkers, boxes and others is carried out in accordance with the requirements of the working drawings. The control is carried out according to the documentation of the manufacturer.

9.4.10 Welded butt joints of stretched, bendable and tensile-bendable load-bearing elements of the frame and ceiling, as well as critical design elements shall be tested by one of the non-destructive methods:

1) solid - when delivered to areas with a cold climate or for structures with an increased level of responsibility;

2) selective, but not less than 20% of the length of the seams - when delivered to areas with a temperate climate and a normal level of responsibility of the structure; Selective inspection is carried out mainly at the intersection of the seams and in places with signs of defects.

Notes:

1 The need and scope of non-destructive testing are established by drawings.

2 In cases where it is impossible to carry out non-destructive testing, the presence of defects in welded seams is allowed to be determined by macrosections made from lead plates.

9.4.11 In welded joints it is not allowed:

cracks of all types and directions located in the weld metal, along the fusion line and in the near-weld zone of the base metal;

lack of penetration (lack of fusion) located at the surface along the section of the welded joint; pores located in the form of a continuous mesh or chains; uncertified craters and burn-throughs; fistulas;

undercuts at the transition points of the seam to the base metal; influxes and inclinations.

9.4.12 In appearance, the seams of welded joints must meet the requirements of 9.4.8 of this standard and not have sagging, burn-through, narrowing, interruptions, as well as a sharp transition to the base metal;

undercuts of the base metal are allowed with a depth of no more than 0.5 mm with a steel thickness of 2 to 10 mm and no more than 1 mm with a steel thickness of over 10 mm; all craters must be welded.

The following discontinuities in welded joints are allowed, which are detected by physical control methods, except for ultrasonic testing:

lack of penetration along the cross-section of the seams in joints accessible for welding from both sides, with a depth of up to 5% of the metal thickness, but not more than 2 mm with a length of lack of penetration of not more than 50 mm, with a distance between them of at least 250 mm and the total length of sections of lack of penetration of not more than 200 mm 1 m seam;

lack of penetration at the root of the seam in joints without backings, accessible for welding only on one side, up to 15% of the metal thickness, but not more than 3 mm;

individual slag inclusions or pores or accumulations of their sizes in diameter not more than 10% of the thickness of the welded metal, but not more than 3 mm;

slag inclusions or pores located in a chain along the seam, with their total length not exceeding 200 mm per 1 m of the seam;

accumulations of gas pores and slag inclusions in separate sections of the weld in an amount of no more than 5 pcs. per 1 cm 2 of the seam area with the diameter of one defect not exceeding 1.5 mm.

The equivalent area of \u200b\u200ba single defect in ultrasonic scanning is taken according to Table 9.

9.4.13 If unacceptable defects are found during selective ultrasonic flaw detection, radiography and gamma-graphing, it is necessary to perform additional control of defective joints at a distance equal to twice the length of the tested section of this joint, mainly in places located near the defective section. If, during additional control, unacceptable defects are found, then the entire seam and doubtful areas of other seams are subject to control.

Identified defective areas of welded seams should be corrected in accordance with 9.4.15 and checked again.

9.4.14 Welded butt joints of design elements of structures are subject to mechanical testing. Control, including the norms for the selection of control plates, is carried out according to the manufacturer's documentation. Control or test plates should be made in the form of a continuation of the welded seam of the product, for which lead-out strips can be used. For mechanical tests, it is allowed to use control plates welded by welders during certification. In this case, the control and production welded joints must be identical.

GOST P 56204-2014

Impact strength tests are carried out at thicknesses of the welded metal over 12 mm.

Seams of control plates welded, as an exception, separately, must be welded by the same welder using the same modes, electrodes and equipment as when welding the product. The dimensions of the blanks (plates), as well as the shape and size of the samples, and the method of cutting them out of the blanks must comply with GOST 6996.

In this case, the following types of tests of the welded joint should be carried out:

tensile - two samples;

for impact bending with a notch in the center of the weld - three samples.

bend (bend) - two samples;

on the hardness of the heat-affected zone in welded joints made of low-alloy steel - at least at three points on one sample, while the hardness should not be more than 250 HB.

The ultimate tensile strength a in should be not less than the lower value of the ultimate tensile strength of the base metal established by the standard or technical conditions for a given steel grade at the same heat treatment mode.

The bend angle and impact strength of welded joints must be at least as specified in Table 10.

Mechanical properties of samples of welded joints should be determined as the arithmetic mean of the results obtained when testing individual samples.

The tests are considered unsatisfactory if at least one of the samples obtained results lower than the established standards by more than 10%, and for impact strength by 0.2 M J / m 2 (2 kgf m / cm 2). If the results are unsatisfactory, the tests are repeated on a double number of samples cut from the same control joint or welded product. Re-inspection is carried out only for the type of mechanical tests for which unsatisfactory results were obtained.

If, upon repeated testing, unsatisfactory results are obtained for at least one of the samples, the overall result for this type of test is considered unsatisfactory, and the seams are unsuitable.

If the test results are unsatisfactory, the defective seam must be removed mechanically or by air-arc gouging, produced according to the manufacturer's documentation. The qualifications of the welder and the quality of the welding consumables must be additionally checked. For steels of grades 12X1MF, 12MX and 12XM, after air-arc gouging, it is necessary to mechanically treat the surface to remove the oxidized layer and control the sample surface for cracks.

9.4.15 Correction of defective welds is carried out according to the manufacturer's documentation in agreement with the Quality Control Department. In this case, seams with cracks and other defects exceeding the permissible ones (see 7.4.12) are removed at a distance exceeding the length of the defective spot by 20 mm (10 mm on each side), and after checking the quality of removal of the defect, they are welded again.

Seam breaks, constrictions and craters are welded. Undercuts of the base metal, exceeding the permissible ones, are cleaned and welded, followed by cleaning, which ensures a smooth transition from the deposited metal to the base metal. Any corrections of minting defects are prohibited. Corrected defects, welds or parts of them must be accepted by the Quality Department.

For all steel grades, it is not allowed to correct the defective area more than three times.

9.5 Methods of control and permissible deviations of linear and angular dimensions, shape

and the location of the surfaces of steel structures and their elements

9.5.1 Methods for monitoring the linear and angular dimensions of steel structures and their elements should provide for the use of standard measuring instruments and, in terms of accuracy, should

meet the requirements of the drawings.

The applied control methods must also ensure the accuracy of measurement of linear and angular dimensions with errors provided for by the relevant regulatory and technical documentation.

9.5.2 Limit deviations (±) of the dimensions of parts made of sheet and structural shapes shall not exceed those indicated in Table 11.

9.3.1 The difference between the diagonals (±) of sheet metal parts, depending on their size, should not exceed that indicated in Table 12.

9.5.4 The displacement (±) of the axes of the holes in the parts from the nominal location should not exceed that indicated in Table 13.

9.5.5 Limit deviations (±) of overall dimensions and the difference in diagonals of finished assembly units of steel structures should not exceed those indicated in Table 14.

GOST P 56204-2014

9.5.6 Limit deviations of the dimensions of assembly units and parts of steel structures not specified in the technical documentation, regardless of the thickness of the metal and the technological method of manufacturing, should be no more than: for holes - according to Н16; for shafts - according to hi6; the rest - by

9.5.7 Limit deviations of the dimensions of parts and elements should not be summed up. The technological process should exclude the accumulation of permissible deviations that make it impossible to assemble the structure as a whole without fitting.

9.5.8 Limit deviations of the shape and location of surfaces in assembly units and parts should not exceed those indicated in Table 15.

GOST P 56204-2014

Introduction

The national standard was prepared by JSC TKZ Krasny Kotelshchik and JSC NPO CKTI. This standard is one of the normative documents included in the evidence base confirming the action of the Technical Regulations of the Customs Union "On the safety of equipment operating under excess pressure" (TR CU 032/2013).

NOTE Limit deviations of the dimensions specified in 9.5.8, 9.5.9 and 9.5.10 refer to sending elements of steel structures.

9.5.9 Limit deviations of dimensions, shape and location of surfaces of elements of steel structures of a composite section (columns, beams, girders and other elements) should not exceed those indicated in Tables 16-19.

Table 16 - Limit deviations of element sizes

Name

Tolerances (±)

Db within the tolerance for the height b of the profile Lb not more than 0.01b

LL within the tolerance for the height L of the profile LL within the double tolerance for the width of the shelf

Flatness

LL within the tolerance for the height L of the profile LL within the double tolerance for the width of the shelf

LL within the tolerance for the height L of the profile LL within the double tolerance for the width of the shelf.

GOST P 56204-2014

NATIONAL STANDARD OF THE RUSSIAN FEDERATION

STATIONARY STEEL STRUCTURE BOILERS

General specifications

Steam and hot-water stationary boilers. Steel structures. General operating specification

Introduction date - 2015-09-01

1 area of \u200b\u200buse

This standard applies to steel structures of stationary boilers, waste heat boilers, hot water and energy technology boilers (hereinafter - boilers) and establishes their classification, technical requirements, as well as rules for control, acceptance, completeness, packing, labeling, transportation, storage and manufacturer's warranty. steel structures.

The standard can be extended to steel structures of other power equipment, if there are no special requirements for them.

The standard is intended for enterprises and organizations that design and manufacture steel structures for boilers.

This standard uses normative references to the following standards:

3.2 According to the conditions of construction and operation: open and semi-open boiler layouts; closed boiler layouts.

3.3 By the level of responsibility:

increased - for thermal power plants with an installed capacity of over 150 MW; normal - for other stations and boiler houses.

3.4 According to the type of fuel used in boilers, solid fuel boilers;

boilers operating on liquid or gaseous fuels; boilers (utilizers) using technological media.

3.5 By the type of element connections: welded;

bolted.

4 General technical requirements

4.1 Steel structures of boilers should be manufactured in accordance with the requirements of this standard for working documentation approved by the developer and accepted for production by the manufacturer.

Working documentation for structures should be developed in accordance with the current regulatory documents in this area. The production technology must be regulated by the technological documentation approved in accordance with the procedure established at the manufacturer.

It is allowed to manufacture steel structures of boilers in accordance with the requirements of other regulatory documents after agreement with the customer.

4.1.1 Material requirements

In standards or technical specifications for structures of specific types, materials for structures and connections should be used, the requirements for which are established in the working documentation developed in accordance with the current regulatory documents. Materials must meet the requirements of standards or technical specifications for their manufacture.

4.2 Requirements for basic materials (rolled steel)

4.2.1 General rules for acceptance, packaging, marking and paperwork for rolled steel supplied for the manufacture of steel structures must comply with the requirements of GOST 7566. If the data of the certificate do not comply with the standard, the rolled steel must be rejected and claim documentation must be drawn up for it.

4.2.2 Incoming materials, semi-finished products and purchased products must comply with the standards and specifications for their manufacture and delivery.

4.2.3 Before the start of the rental in production, the presence of marking and its compliance with certificates should be checked.

In the absence of certificates, the manufacturer is obliged to subject the rolled product to all types of tests provided for the required steel grade. The rental is allowed to be put into production if the data obtained during the tests are not lower than those guaranteed by the standards and specifications.

4.2.4 When cutting off a part of a beam, sheet, strip, pipe, and other blanks, the marking should be retained or restored on the remaining part. The marking must be surrounded by indelible paint.

4.2.5 Rolled steel should be stored, as a rule, in closed rooms with storing in stable piles. When storing rolled steel without a canopy, the metal should be laid with a slope to ensure water drainage.

4.2.6 Steel flat washers and spacers used in stacks should have rounded corners without burrs or debris. When performing loading and unloading operations and lifting and transporting operations, it is necessary to use devices that exclude the formation of permanent deformations and crushing of steel.

4.3 Requirements for welding consumables

4.3.1 In this standard, for welding consumables used in the manufacture of steel

structures are classified as: electrodes, welding wire, flux, gases and liquids.

4.3.2 Welding consumables supplied to the manufacturer of steel structures must be supplied in accordance with applicable standards and specifications and undergo incoming inspection and testing in accordance with the requirements of GOST 24297.

4.3.3 Welding consumables used for manual arc, semi-automatic and automatic welding of steel structure elements must comply with the requirements of the current standards and the data in Table 1.

4.3.4 Welding consumables should be stored separately by brands and lots in a heated and dry room. The flux should be stored in a closed container.

4.4 Requirements for straightening, bending and marking of rolled steel

4.4.1 Straightening of rolled steel and parts made from it should be done, as a rule, on rollers and presses using mechanized devices and staples, and straightening of small parts on a plate with a smoothing trowel. Straightening by imposing false weld beads is not allowed.

Note-For universal and flat steel, with a rib curvature twice as high as indicated in table 2, it is allowed to straighten rolled products by heating the flame of a gas burner from the side of the convex edge. Hot straightening is allowed only at a temperature of at least 700 ° C.

4.4.2 Bending of parts in hot and cold condition should be carried out according to the technological documentation of the manufacturer on rollers and presses, and in some cases (for small parts) can be done manually.

4.4.3 After the end of hot straightening and bending, the cooling rate of the parts should exclude hardening, warpage, residual stresses, cracks, tears. Intensive cooling is not allowed.

4.4.4 After bending and straightening, the parts should not have cracks. Separate nicks, dents and other surface defects that do not bring the thickness of the rolled product beyond the minus permissible deviation are acceptable. The control of parts after bending and straightening should be carried out in accordance with

in accordance with the requirements of design and technological documentation.

4.4.5 For design and critical elements made of rolled steel, straightening and bending in a cold state is permissible if the deformation of the steel (radius of curvature and deflection arrow) does not exceed the limits established in Table 2.

Radius of curvature R, not less

Arrow deflection f,