GB 50235-1997 Code for construction and acceptance of industrial metal pipeline projects
Some standard content:
Engineering Construction Standard Full-text Information System
National Standard of the People's Republic of China
GB50235-97
Code for construction and acceptance ofindustrial metallic piping
5 Issued
1997-10-05
State Bureau of Technical Supervision
Ministry of Construction of the People's Republic of China
Engineering Construction Standard Full-text Information System
1998-05-01
Jointly Issued
Engineering Construction Standard Full-text Information System
National Standard of the People's Republic of China
Code for construction and acceptance ofindustrial metallic piping ofindustrialmetallicpiping
50235-97
Editor:Ministry of Chemical Industry of the People's Republic of ChinaApproval:Ministry of Construction of the People's Republic of ChinaEffective Date:May 1, 1998
1998Beijing
Engineering Construction Standard Full Text Information System
Engineering Construction Standard Full Text Information System
Notice on the Release of the National Standard
"Industrial Metal Piping Engineering
Construction and Acceptance Specification"
Jianbiao [1997] No. 278
According to the requirements of the State Planning Commission's Document No. [1991] 290, the "Industrial Metal Piping Engineering Construction and Acceptance Specification" revised by the Ministry of Chemical Industry and relevant departments has been reviewed by relevant departments. The "Industrial Metal Piping Engineering Construction and Acceptance Specification" GB50235-97 is now approved as a mandatory national standard and will be implemented on May 1, 1998. The original "Industrial Pipeline Engineering Construction and Acceptance Code" (Metal Pipeline) (GBJ235-82) is abolished at the same time.
This code is managed by the Ministry of Chemical Industry, and its specific interpretation and other work are the responsibility of the Construction Standardization Management Center of the Ministry of Chemical Industry, and its publication and distribution are organized by the Standard Quota Research Institute of the Ministry of Construction.
Ministry of Construction of the People's Republic of China
October 5, 1997
Engineering Construction Standard Full Text Information System
Engineering Construction Standard Full Text Information System
1 General Principles
Terms:
Inspection of pipeline components and pipeline supports..0........
Pipeline processing·
Pipe cutting......
Bending pipe production·
Tube coiling processing
Tube mouth flanging
Jacket pipe processing
Pipeline Welding
Pipeline installation
General provisions
Pipeline prefabrication
Steel pipeline installation
Pipeline installation for connecting machines
Cast iron pipeline installation
Non-ferrous metal pipeline installation
Heating pipe and jacketed pipe installation
Anti-corrosion lined pipeline installation
Valve installation
Compensation device installation
Support and hanger installation
Static grounding installation
7 Pipeline inspection, examination and testing
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6000040600000000000000505
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Engineering construction standard full-text information system
General provisions
Appearance inspection
Non-destructive inspection of weld surface
Radiographic inspection and ultrasonic inspection
7.5 Pressure test
Purge and cleaning of pipelines
-General provisions
Water flushing
Air purging
Steam purging
Chemical cleaning
Oil cleaning
Pipeline painting
Pipeline insulation
Project handover and acceptance
Appendix A
Appendix B
Appendix C
Contents and format of technical documents for handover
.......
Common groove forms and sizes for pipeline welding Explanation of terms used in this specification
Additional explanation
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Engineering Construction Standard Full-text Information System
1 General Provisions
In order to improve the construction level of industrial metal pipeline projects and ensure the quality of projects, 1.0.1
This specification is formulated.
1.0.2 This specification applies to the construction and acceptance of industrial metal pipelines (hereinafter referred to as "pipelines") with a design pressure not exceeding 42MPa and a design temperature not exceeding the allowable use temperature of the material.
1.0.3 This specification does not apply to special pipelines for nuclear power plants, special pipelines for mines, and long-distance pipelines.
1.0.4 The construction of pipelines shall be carried out in accordance with the design documents. When the design is modified, it shall be confirmed by the original design unit and agreed by the construction unit. 1.0.5 The pipelines belonging to machines or equipment assembled on site shall be implemented in accordance with the technical documents of the manufacturer, but the quality standards shall not be lower than the provisions of this specification. 1.0.6
3 In addition to the provisions of this specification, the construction of pipelines shall also comply with the relevant current national standards and specifications. Regulations.
Engineering Construction Standards Full Text Information System
Engineering Construction Standards Full Text Information System
2.0.1 Piping
2 Terminology
It is composed of pipeline components and pipeline supports, and is an assembly of pipes, pipe fittings, flanges, bolted connections, gaskets, valves and other components or pressure-bearing parts used to transport, distribute, mix, separate, discharge, measure, control or stop the flow of fluids. 2.0.2 Piping components pipingcomponents Components used to connect or assemble pipelines. It includes pipes, pipe fittings, flanges, gaskets, fasteners, valves, expansion joints, flexible joints, pressure-resistant hoses, steam traps, filters and separators.
2.0. 3 Pipe-supporting elements are the general term for pipe-mounting parts and attachments.
2.0.4 FixturesbzxZ.net
Elements that transfer loads from pipes or pipe attachments to supporting structures or equipment. They include hangers, spring supports, diagonal rods, counterweights, tension bolts, support rods, chains, guide rails, anchors, saddles, pads, rollers, brackets and sliding brackets. 2.0.5 Structural attachments are parts attached to pipes by welding, bolting or clamping, including pipe hangers, hanging (support) ears, rings, clamps, hanging clamps, fastening splints and skirt-type pipe seats. 2.0.6 Highly toxic fluids are lethal Fluid
If a very small amount of this substance leaks into the environment, is inhaled or comes into contact with the human body, even if it is treated quickly, it can cause serious and difficult-to-treat damage to the human body. Equivalent to the poison of level I in the current national standard "Classification of Hazards of Occupational Exposure to Toxic Substances".
2.0.7 Toxic fluid
toxicfluid
This substance leaks into the environment, is inhaled or comes into contact with the human body, and if it is treated in time, it will not cause irreversible damage to the human body. Equivalent to the poison of level I and below in the current national standard "Classification of Hazards of Occupational Exposure to Toxic Substances". 2.0.8 Flammable fluid
Gases that can be ignited and continuously burned or liquids that can be vaporized under production operation conditions.
2.0.9 Fluid transportation piping
fluidtransportationpiping
refers to the pipelines for transporting various fluids specified in the design documents by the design unit after comprehensive consideration of the fluid properties, operating conditions and other basic factors such as the composition management design. Fluids can be divided into highly toxic fluids, toxic fluids, flammable fluids, non-flammable fluids and non-toxic fluids.
2.0.10 Hot bending
Bending operation when the temperature is higher than the metal critical point ACi. 2.0.11 Cold bending
Bending operation when the temperature is lower than the metal critical point AC. 2.0.12Tightening in hot conditionTightening operation to prevent leakage of detachable joints due to thermal expansion at working temperature.
2.0.13Tightening in cold conditionTightening operation to prevent leakage of detachable joints due to cold contraction at working temperature.
2.0.14100% radiographic examination100% radiographic examinationA full circumferential radiographic examination of all circumferential butt welds of a specified batch of pipelines and a full-length radiographic examination of longitudinal welds. 2.0.15Random radiographic examinationA full circumferential radiographic examination of a specified percentage of circumferential butt welds in a specified batch of pipelines. It is only applicable to circumferential butt welds. 2.0.16Pressure testpressuretest
A test to gradually pressurize the pipeline with liquid or gas as the medium to reach the specified pressure to test the strength and tightness of the pipeline. Engineering Construction Standard Full Text Information System
Engineering Construction Standard Full Text Information System
2.0.17 Leakage test
leaktest
A test that uses gas as the medium and uses a foaming agent, a color developer, a gas molecule sensor or other special means to check the leak points in the pipeline system under the design pressure. 2.0.18 Resetting recovering the original state The process of restoring the original state of an installed qualified pipeline after disassembly. 2.0.19 Single-line diagram
Isometric diagram
Draw each pipeline as an empty view of the pipeline represented by a single line according to the drawing method of axial projection.
Free pipe segments pipe-segments to be prefabricated 2.0.20
Before prefabrication of the pipeline, select the pipe segments that can be processed first according to the single-line diagram.
2.0.21 Closed pipe segments for dimension adjustment Before the prefabrication of the pipeline, the pipe segments are selected and determined according to the single-line diagram and processed after the actual installation dimensions are measured.
Engineering Construction Standard Full Text Information System
Engineering Construction Standard Full Text Information System
3 Inspection of pipeline components and pipeline supports 3.0.1 Pipe components and pipeline supports must have a quality certificate from the manufacturer, and their quality must not be lower than the provisions of the current national standards. 3.0.2 The material, specification, model and quality of pipeline components and pipeline supports shall comply with the provisions of the design documents, and shall be inspected for appearance according to the current national standards. Unqualified ones shall not be used.
3.0.3 Alloy steel pipeline components shall be re-inspected for material by spectral analysis or other methods, and shall be marked. The material of the internal parts of alloy steel valves shall be spot-checked, and the number of spot checks for each batch (same manufacturer, same specification, same model, and delivered at the same time, the same below) shall not be less than 1. 3.0.4 The lining quality of anti-corrosion lined pipelines shall comply with the provisions of the current national standard "Industrial Equipment, Pipeline Anti-corrosion Engineering Construction and Acceptance Specifications". 3.0.5 The valves of the following pipelines shall be subjected to shell pressure test and sealing test one by one. Those that fail to meet the standards shall not be used.
3.0.5.1 Valves for pipelines that transport highly toxic fluids, toxic fluids, and flammable fluids; 3.0.5.2 Valves for pipelines that transport non-flammable fluids and non-toxic fluids with a design pressure greater than 1MPa or a design pressure less than or equal to 1MPa and a design temperature less than -29℃ or greater than 186℃.
3.0.6 Valves for pipelines that transport non-flammable fluids and non-toxic fluids with a design pressure less than or equal to 1MPa and a design temperature of -29~186℃ shall be sampled from each batch. 10%, and not less than 1, shall be sampled for shell pressure test and sealing test. If the valves fail to meet the standards, they shall be double sampled. If they still fail to meet the standards, the batch of valves shall not be used. 3.0.7 The shell test pressure of the valve shall not be less than 1.5 times the nominal pressure, and the test time shall not be less than 5 minutes. The shell packing shall be qualified if there is no leakage; the sealing test should be carried out at the nominal pressure, and the valve disc sealing surface shall be qualified if there is no leakage. 30.8 The valves that have passed the test should be drained of internal water in time and blown dry. Except for valves that need to be degreased, anti-rust oil should be applied to the sealing surface, the valve should be closed, the inlet and outlet should be sealed, and obvious marks should be made. The "Valve Test Record" should be filled in according to the format specified in Article A.0.1 of Appendix A of this specification.
3.0.9 For gate valves with a nominal pressure less than 1MPa and a nominal diameter greater than or equal to 600mm, the shell pressure test and gate seal test may not be carried out separately. The shell pressure test should be carried out according to the test pressure of the pipeline system during the system pressure test. The gate seal test can be inspected by color printing and other methods, and the color printing on the joint surface should be continuous. 3.0.10 The safety valve shall be tested and adjusted according to the opening pressure specified in the design documents. The pressure shall be stable during pressure adjustment, and each safety valve shall be tested for opening and closing for no less than 3 times. After commissioning, the "Safety Valve Initial Commissioning Record" shall be filled in according to the format specified in Article A.0.2 of Appendix A of this specification. 3.0.11 For valves with steam jackets, the jacket part shall be pressure tested at 1.5 times the steam working pressure.
3.0.12 For materials that require low-temperature impact toughness testing in the design documents, the supplier shall provide documents on the results of the low-temperature impact toughness test, and the indicators shall not be lower than those specified in the design documents.
For stainless steel pipes and pipe fittings that require intergranular corrosion testing in the design documents, the supplier shall provide documents on the results of the intergranular corrosion test, and the indicators shall not be lower than those specified in the design documents.
3.0.14 Pipeline components and pipeline supports shall be properly kept during construction and shall not be mixed or damaged. Their color codes or markings shall be obvious and clear. Pipeline components and pipe supports made of stainless steel and nonferrous metals shall not come into contact with carbon steel during storage. The pipes that cannot be installed temporarily should have their openings sealed. Construction Standards Full-text Information System
Engineering Construction Standards Full-text Information System
Pipeline Processing
4.1 Pipe Cutting
Steel Stamp.
The original mark should be transplanted before the pipe is cut. Low-temperature steel pipes and titanium pipes are strictly prohibited from use. 4.1.2
Carbon steel pipes and alloy steel pipes should be cut mechanically. When cutting with oxyacetylene flame, the correct size and smooth surface must be ensured. 4.1.3 Stainless steel pipes and nonferrous metal pipes should be cut mechanically or by plasma. When stainless steel pipes and titanium pipes are cut or polished with a grinding wheel, a special grinding wheel should be used. 4.1.4 Galvanized steel pipes should be cut with a hacksaw or mechanically. 4.1.5 The quality of pipe cuts shall meet the following requirements: 1 The cut surface shall be flat, free of cracks, heavy skin, burrs, bumps, shrinkage, molten slag, oxides, iron filings, etc.
4.1.5.2 The inclination deviation of the cut end face △ (Figure 4.1.5) shall not be greater than 1% of the outer diameter of the pipe and shall not exceed 3mm.
Engineering Construction Standards Full Text Information System
Tip cut end face inclination deviation0.19 Single-line diagram
Isometric diagram
Draw each pipeline as a single-line empty view of the pipeline according to the drawing method of axial projection.
Free pipe segments pipe-segments to be prefabricated 2.0.20
Before prefabrication of the pipeline, select the pipe segments that can be processed first according to the single-line diagram.
2.0.21 Closed pipe segments pipe-segments for dimension adjustment Before prefabrication of the pipeline, select the pipe segments that can be processed after the actual installation dimensions are measured according to the single-line diagram.
Engineering Construction Standard Full-text Information System
Engineering Construction Standard Full-text Information System
3 Inspection of pipeline components and pipeline supports 3.0.1 Pipe components and pipeline supports must have a quality certificate from the manufacturer, and their quality must not be lower than that specified in the current national standards. 3.0.2 The material, specification, model and quality of pipeline components and pipeline support parts shall comply with the provisions of the design documents, and shall be inspected for appearance according to the current national standards. Those that fail to meet the standards shall not be used.
3.0.3 The material of alloy steel pipeline components shall be re-inspected by spectral analysis or other methods, and shall be marked. The internal material of alloy steel valves shall be spot-checked, and the number of spot-checks for each batch (same manufacturer, same specification, same model, and arrived at the same time, the same below) shall not be less than 1. 3.0.4 The lining quality of anti-corrosion lined pipelines shall comply with the provisions of the current national standard "Construction and Acceptance Specifications for Industrial Equipment and Pipeline Anti-corrosion Engineering". 3.0.5 The valves of the following pipelines shall be subjected to shell pressure tests and sealing tests one by one. Those that fail to meet the standards shall not be used.
3.0.5.1 Valves for pipelines conveying highly toxic fluids, toxic fluids, and flammable fluids; 3.0.5.2 Valves for pipelines conveying non-flammable fluids and non-toxic fluids with a design pressure greater than 1MPa or a design pressure less than or equal to 1MPa and a design temperature less than -29℃ or greater than 186℃.
3.0.6 Valves for pipelines conveying non-flammable fluids and non-toxic fluids with a design pressure less than or equal to 1MPa and a design temperature of -29~186℃ shall be sampled from each batch of 10%, and not less than 1, for shell pressure test and sealing test. If the valves fail to meet the standards, they shall be double sampled. If they still fail to meet the standards, the batch of valves shall not be used. 3.0.7 The shell test pressure of the valve shall not be less than 1.5 times the nominal pressure, and the test time shall not be less than 5 minutes. The valves shall be qualified if there is no leakage in the shell packing; the sealing test should be carried out at the nominal pressure, and the valve disc sealing surface shall be qualified if there is no leakage. 30.8 Valves that pass the test shall be drained of internal water in time and blown dry. Except for valves that need to be degreased, anti-rust oil should be applied to the sealing surface, the valve should be closed, the inlet and outlet should be sealed, and obvious marks should be made. The "Valve Test Record" should be filled in according to the format specified in Article A.0.1 of Appendix A of this specification.
3.0.9 For gate valves with a nominal pressure less than 1MPa and a nominal diameter greater than or equal to 600mm, shell pressure test and gate seal test may not be carried out separately. The shell pressure test should be carried out according to the test pressure of the pipeline system during the system pressure test. The gate seal test can be inspected by color printing and other methods. The color printing on the joint surface should be continuous. 3.0.10 The safety valve should be tested and adjusted according to the opening pressure specified in the design documents. The pressure should be stable during pressure adjustment, and each safety valve should be opened and closed for no less than 3 times. After commissioning, the "Safety Valve Initial Commissioning Record" should be filled in according to the format specified in Article A.0.2 of Appendix A of this specification. 3.0.11 For valves with steam jackets, the jacket part shall be pressure tested at 1.5 times the steam working pressure.
3.0.12 For materials that require low-temperature impact toughness testing in the design documents, the supplier shall provide documents showing the results of the low-temperature impact toughness testing, and the index shall not be lower than that specified in the design documents.
For stainless steel pipes and pipe fittings that require intergranular corrosion testing in the design documents, the supplier shall provide documents showing the results of the intergranular corrosion testing, and the index shall not be lower than that specified in the design documents.
3.0.14 Pipeline components and pipeline supports shall be properly stored during construction and shall not be mixed or damaged. Their color codes or markings shall be clear and distinct. Pipeline components and pipeline supports made of stainless steel or nonferrous metals shall not come into contact with carbon steel during storage. Pipes that cannot be installed temporarily shall have their openings sealed. Construction Standard Full Text Information System
Engineering Construction Standard Full Text Information System
Pipeline Processing
4.1 Pipe Cutting
Steel Stamp.
The original mark should be transplanted before the pipe is cut. Low-temperature steel pipes and titanium pipes are strictly prohibited. 4.1.2
Carbon steel pipes and alloy steel pipes should be cut mechanically. When using oxyacetylene flame cutting, the correct size and smooth surface must be ensured. 4.1.3 Stainless steel pipes and non-ferrous metal pipes should be cut mechanically or plasma. When stainless steel pipes and titanium pipes are cut or polished with grinding wheels, special grinding wheels should be used. 4.1.4 Galvanized steel pipes should be cut with hacksaws or mechanical methods. 4.1.5 The quality of pipe cuts should meet the following requirements: 1 The cut surface should be smooth, without cracks, heavy skin, burrs, convex and concave, shrinkage, molten 4.1.5.1
slag, oxides, iron filings, etc.
4.1.5.2 The inclination deviation of the cut end face △ (Figure 4.1.5) should not be greater than 1% of the outer diameter of the pipe and should not exceed 3mm.
Engineering Construction Standards Full Text Information System
Tip cut end face inclination deviation0.19 Single-line diagram
Isometric diagram
Draw each pipeline as a single-line empty view of the pipeline according to the drawing method of axial projection.
Free pipe segments pipe-segments to be prefabricated 2.0.20
Before prefabrication of the pipeline, select the pipe segments that can be processed first according to the single-line diagram.
2.0.21 Closed pipe segments pipe-segments for dimension adjustment Before prefabrication of the pipeline, select the pipe segments that can be processed after the actual installation dimensions are measured according to the single-line diagram.
Engineering Construction Standard Full-text Information System
Engineering Construction Standard Full-text Information System
3 Inspection of pipeline components and pipeline supports 3.0.1 Pipe components and pipeline supports must have a quality certificate from the manufacturer, and their quality must not be lower than that specified in the current national standards. 3.0.2 The material, specification, model and quality of pipeline components and pipeline support parts shall comply with the provisions of the design documents, and shall be inspected for appearance according to the current national standards. Those that fail to meet the standards shall not be used.
3.0.3 The material of alloy steel pipeline components shall be re-inspected by spectral analysis or other methods, and shall be marked. The internal material of alloy steel valves shall be spot-checked, and the number of spot-checks for each batch (same manufacturer, same specification, same model, and arrived at the same time, the same below) shall not be less than 1. 3.0.4 The lining quality of anti-corrosion lined pipelines shall comply with the provisions of the current national standard "Construction and Acceptance Specifications for Industrial Equipment and Pipeline Anti-corrosion Engineering". 3.0.5 The valves of the following pipelines shall be subjected to shell pressure tests and sealing tests one by one. Those that fail to meet the standards shall not be used.
3.0.5.1 Valves for pipelines conveying highly toxic fluids, toxic fluids, and flammable fluids; 3.0.5.2 Valves for pipelines conveying non-flammable fluids and non-toxic fluids with a design pressure greater than 1MPa or a design pressure less than or equal to 1MPa and a design temperature less than -29℃ or greater than 186℃.
3.0.6 Valves for pipelines conveying non-flammable fluids and non-toxic fluids with a design pressure less than or equal to 1MPa and a design temperature of -29~186℃ shall be sampled from each batch of 10%, and not less than 1, for shell pressure test and sealing test. If the valves fail to meet the standards, they shall be double sampled. If they still fail to meet the standards, the batch of valves shall not be used. 3.0.7 The shell test pressure of the valve shall not be less than 1.5 times the nominal pressure, and the test time shall not be less than 5 minutes. The valves shall be qualified if there is no leakage in the shell packing; the sealing test should be carried out at the nominal pressure, and the valve disc sealing surface shall be qualified if there is no leakage. 30.8 Valves that pass the test shall be drained of internal water in time and blown dry. Except for valves that need to be degreased, anti-rust oil should be applied to the sealing surface, the valve should be closed, the inlet and outlet should be sealed, and obvious marks should be made. The "Valve Test Record" should be filled in according to the format specified in Article A.0.1 of Appendix A of this specification.
3.0.9 For gate valves with a nominal pressure less than 1MPa and a nominal diameter greater than or equal to 600mm, shell pressure test and gate seal test may not be carried out separately. The shell pressure test should be carried out according to the test pressure of the pipeline system during the system pressure test. The gate seal test can be inspected by color printing and other methods. The color printing on the joint surface should be continuous. 3.0.10 The safety valve should be tested and adjusted according to the opening pressure specified in the design documents. The pressure should be stable during pressure adjustment, and each safety valve should be opened and closed for no less than 3 times. After commissioning, the "Safety Valve Initial Commissioning Record" should be filled in according to the format specified in Article A.0.2 of Appendix A of this specification. 3.0.11 For valves with steam jackets, the jacket part shall be pressure tested at 1.5 times the steam working pressure.
3.0.12 For materials that require low-temperature impact toughness testing in the design documents, the supplier shall provide documents showing the results of the low-temperature impact toughness testing, and the index shall not be lower than that specified in the design documents.
For stainless steel pipes and pipe fittings that require intergranular corrosion testing in the design documents, the supplier shall provide documents showing the results of the intergranular corrosion testing, and the index shall not be lower than that specified in the design documents.
3.0.14 Pipeline components and pipeline supports shall be properly stored during construction and shall not be mixed or damaged. Their color codes or markings shall be clear and distinct. Pipeline components and pipeline supports made of stainless steel or nonferrous metals shall not come into contact with carbon steel during storage. Pipes that cannot be installed temporarily shall have their openings sealed. Construction Standard Full Text Information System
Engineering Construction Standard Full Text Information System
Pipeline Processing
4.1 Pipe Cutting
Steel Stamp.
The original mark should be transplanted before the pipe is cut. Low-temperature steel pipes and titanium pipes are strictly prohibited. 4.1.2
Carbon steel pipes and alloy steel pipes should be cut mechanically. When using oxyacetylene flame cutting, the correct size and smooth surface must be ensured. 4.1.3 Stainless steel pipes and non-ferrous metal pipes should be cut mechanically or plasma. When stainless steel pipes and titanium pipes are cut or polished with grinding wheels, special grinding wheels should be used. 4.1.4 Galvanized steel pipes should be cut with hacksaws or mechanical methods. 4.1.5 The quality of pipe cuts should meet the following requirements: 1 The cut surface should be smooth, without cracks, heavy skin, burrs, convex and concave, shrinkage, molten 4.1.5.1
slag, oxides, iron filings, etc.
4.1.5.2 The inclination deviation of the cut end face △ (Figure 4.1.5) should not be greater than 1% of the outer diameter of the pipe and should not exceed 3mm.
Engineering Construction Standards Full Text Information System
Tip cut end face inclination deviation9 For gate valves with a nominal pressure less than 1MPa and a nominal diameter greater than or equal to 600mm, it is not necessary to conduct separate shell pressure tests and gate seal tests. The shell pressure test should be conducted according to the test pressure of the pipeline system during the system pressure test. The gate seal test can be inspected by color printing and other methods. The color printing on the joint surface should be continuous. 3.0.10 The safety valve should be tested and adjusted according to the opening pressure specified in the design documents. The pressure should be stable during pressure adjustment, and each safety valve should be tested for at least 3 times. After commissioning, the "Safety Valve Initial Commissioning Record" should be filled in according to the format specified in Article A.0.2 of Appendix A of this specification. 3.0.11 For valves with steam jackets, the jacket part should be pressure tested at 1.5 times the steam working pressure.
3.0.12 For materials that require low-temperature impact toughness tests in the design documents, the supplier should provide documents on the results of the low-temperature impact toughness tests, and the indicators should not be lower than those specified in the design documents.
For stainless steel pipes and pipe fittings that require intergranular corrosion tests in the design documents, the supplier shall provide documents on the results of the intergranular corrosion tests, and the indicators shall not be lower than those specified in the design documents.
3.0.14 Pipeline components and pipe supports shall be properly kept during construction and shall not be mixed or damaged. Their color codes or markings shall be clear and distinct. Pipeline components and pipe supports made of stainless steel or non-ferrous metals shall not come into contact with carbon steel during storage. Pipes that cannot be installed temporarily shall have their openings sealed. Construction Standard Full-text Information System
Engineering Construction Standard Full-text Information System
Pipeline Processing
4.1 Pipe Cutting
Steel Stamping.
The original marking shall be transplanted before the pipe is cut. Low-temperature steel pipes and titanium pipes are strictly prohibited. 4.1.2
Carbon steel pipes and alloy steel pipes should be cut mechanically. When cutting with oxyacetylene flame, the correct size and smooth surface must be ensured. 4.1.3 Stainless steel pipes and nonferrous metal pipes should be cut mechanically or by plasma. When stainless steel pipes and titanium pipes are cut or polished with a grinding wheel, special grinding wheels should be used. 4.1.4 Galvanized steel pipes should be cut with a hacksaw or mechanically. 4.1.5 The quality of pipe cuts should meet the following requirements: 1 The cut surface should be flat, free of cracks, heavy skin, burrs, bumps, shrinkage, molten slag, oxides, iron filings, etc.
4.1.5.2 The inclination deviation △ of the cut end face (Figure 4.1.5) should not be greater than 1% of the outer diameter of the pipe, and shall not exceed 3mm.
Engineering Construction Standards Full-text Information System
Tilting deviation of pipe cut end face9 For gate valves with a nominal pressure less than 1MPa and a nominal diameter greater than or equal to 600mm, it is not necessary to conduct separate shell pressure tests and gate seal tests. The shell pressure test should be conducted according to the test pressure of the pipeline system during the system pressure test. The gate seal test can be inspected by color printing and other methods. The color printing on the joint surface should be continuous. 3.0.10 The safety valve should be tested and adjusted according to the opening pressure specified in the design documents. The pressure should be stable during pressure adjustment, and each safety valve should be tested for at least 3 times. After commissioning, the "Safety Valve Initial Commissioning Record" should be filled in according to the format specified in Article A.0.2 of Appendix A of this specification. 3.0.11 For valves with steam jackets, the jacket part should be pressure tested at 1.5 times the steam working pressure.
3.0.12 For materials that require low-temperature impact toughness tests in the design documents, the supplier should provide documents on the results of the low-temperature impact toughness tests, and the indicators should not be lower than those specified in the design documents.
For stainless steel pipes and pipe fittings that require intergranular corrosion tests in the design documents, the supplier shall provide documents on the results of the intergranular corrosion tests, and the indicators shall not be lower than those specified in the design documents.
3.0.14 Pipeline components and pipe supports shall be properly kept during construction and shall not be mixed or damaged. Their color codes or markings shall be clear and distinct. Pipeline components and pipe supports made of stainless steel or non-ferrous metals shall not come into contact with carbon steel during storage. Pipes that cannot be installed temporarily shall have their openings sealed. Construction Standard Full-text Information System
Engineering Construction Standard Full-text Information System
Pipeline Processing
4.1 Pipe Cutting
Steel Stamping.
The original marking shall be transplanted before the pipe is cut. Low-temperature steel pipes and titanium pipes are strictly prohibited. 4.1.2
Carbon steel pipes and alloy steel pipes should be cut mechanically. When cutting with oxyacetylene flame, the correct size and smooth surface must be ensured. 4.1.3 Stainless steel pipes and nonferrous metal pipes should be cut mechanically or by plasma. When stainless steel pipes and titanium pipes are cut or polished with a grinding wheel, special grinding wheels should be used. 4.1.4 Galvanized steel pipes should be cut with a hacksaw or mechanically. 4.1.5 The quality of pipe cuts should meet the following requirements: 1 The cut surface should be flat, free of cracks, heavy skin, burrs, bumps, shrinkage, molten slag, oxides, iron filings, etc.
4.1.5.2 The inclination deviation △ of the cut end face (Figure 4.1.5) should not be greater than 1% of the outer diameter of the pipe, and shall not exceed 3mm.
Engineering Construction Standards Full-text Information System
Tilting deviation of pipe cut end face
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