UllC NATIONAL STANDARD OF THE PEOPLE'S REPUBLIC OF CHINA p r:fl ~A ~~'Jl IE r@ ~t"flit GB 50235-2010 Code for Construction of Industrial Metallic Piping Engineering GB 50235-2010 -- How to BUY & immediately GET a full-copy of this standard? 1. www.chinesestandard.net; 2. Search --> Add to Cart --> Checkout (3-steps); 3. No action is required - Full-copy of this standard will be automatically & immediately delivered to your EMAIL address in 0~60 minutes. Issued on: August 4. 18, Support: 2010 Sales@ChineseStandard.net. Wayne, Implemented Sales manager on: June 1, 2011 Jointly Issued by Ministry of Housing and Urban-Rural Construction of the People's Republic of China General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China
Contents General Provisions........... 1 2 Terms and Symbols......... 2 2.1 Terms...... 2 2.2 Symbols................. 4 3 Basic Requirements..................... 6 3.1 General Require1nents.................... 6 3.2 Grading... 6 4 Inspection of Pipework Components and Materials...... 7 4.1 General Requirements....................................... 7 4.2 Valve Inspection............ 7 4.3 Inspection of Other Pipework Components... 8 5 Machining of Piping......,... 10 5.1 General Requirement..................... 10 5.2 Pipe Cutting...... 10 5.3 Bending Fabrication......... I 0 5.4 Machining of Rolling Pipe................. 13 5.5 Flanging Edge of Pipe Orvfice............. 14 5.6 Machining of Jacket Piping............ 15 5.7 Fabrication of Miter Elbow...... 16 5.8 Fabrication of Piping Support and Hanger............. 16 6 Welding and Heat-Treatment After Welding of Piping... 18 7 Installation of Piping...................... 23 7.1 General Requirement.............. 23 7.2 Prefabricating for Pipe segment...... 24 7.3 Steel Piping Installation................... 24 7.4 Piping Installation of Coupling Equipment........ 27 7.5 Cast Iron Piping Installation.................... 28 7.6 Installation of Stainless Steel Piping and Non-Ferrous Piping... 29 7. 7 Heat Tracing Piping Installation......... 30
7.8 Jacket Piping Installation... 31 7.9 Installation of Anti-Corrosion Lining Piping... 32 7.10 Valve Installation... 32 7.11 Expansion Joint Installation... 33 7.12 Installation of Piping Support and Hanger... 36 7.13 Installation of Static Electricity Grounding... 38 8 Inspection, Examination and Test of Piping... 39 8.1 General Requirement.... 39 8.2 Visual Examination... 39 8.3 Non-Destructive Testing of Welding Seam Surface... 39 8.4 Radiographic and Ultrasonic Examinations of Welding Seam... 40 8.5 Hardness Inspection and Other Inspections...40 8.6 Pressure Test... 41 9 Piping Cleaning and Blowing... 46 9.1 General Requirement....... 46 9.2 Water Washing... 47 9.3 Air Blowing... 47 9.4 Steam Blowing... 48 9.5 Degreasing... 48 9.6 Chemical Cleaning... 49 9. 7 Oil Cleaning........ 49 10 Engineering Delivery... 51 Appendix A Content and the Format for the Record of the Inspection on the Construction Quality. 53 Explanation of Wording in This Code... 70 List of Quoted Standards... 71
1 General Provisions 1.0.1 This code is formulated with a view to improving the construction level of industrial metallic piping engineering, strengthening the quality control in the industrial metallic piping construction, and guaranteeing the construction quality. 1.0.2 This code is applicable to the construction of industrial metallic piping whose design pressure is not higher than 42MPa and design temperature is not higher than the allowable service temperature of the material hereof. 1.0.3 This code is not applicable to the constructions of the following industrial metallic piping: 1 Piping of prospecting and extraction devices used for petroleum, natural gas, terrestrial heat; 2 Long-distance piping; 3 Piping special for nuclear energy plant; 4 Piping for offshore facility and mining shaft; 5 Piping for heating ventilation and air conditioning, or non-circular section piping. 1.0.4 The industrial metallic piping construction shall be carried out according to the requirements of the design document and this code. 1.0.5 Where the design document needs be modified or the material needs be substituted, it shall be approved by the original design organization and issued with the written document. 1.0.6 The construction of the piping for field assembly equipment shall comply with the requirements of the manufacturer's technical documentation, and shall not be inferior to the ones specified in this code. 1.0.7 This code shall apply in conjunction with the current national standard "Code for Acceptance of Construction Quality of Industrial Metallic Piping Engineering" GB 50184. 1.0.8 The construction of anticorrosive engineering for industrial metallic piping shall meet the requirements of the national current relevant standard and design document. 1.0.9 The construction of heat insulation engineering for industrial metallic piping shall meet the requirements of the current national standard "Code for Construction of Industrial Equipment and Piping Insulation Engineering" GB 50126 and the design document. 1.0.10 The construction of industrial metallic piping, shall meet the requirements of the national current relevant standards, besides this code.
2 Terms and Symbols 2.1 Terms 2.1.1 Nominal pressure (PN) for pipe-work components A method of indication to express nominal pressure grade of pipework component by using the combination of letters PN and dimensionless numbers. 2.1.2 Nominal size for pipework components A method of indication to express nominal size of pipework component by using the combination of letters DN and dimensionless numbers. 2.1.3 Industrial metallic piping Process piping, public engineering piping and other subsidiary piping made by connection or assembling with metallic pipework components, used to convey processing medium in production equipments. 2.1.4 Pressure piping Piping with maximum working pressure larger than or equal to O.lMPa (gauge pressure) and nominal size higher than 25mm, used to convey gas, liquefied gas, free steam or combustible, explosive, toxic and corrosive liquid medium with maximum working temperature higher than or equal to the normal boiling point. 2.1.5 D-type fluid piping Incombustible, nontoxic or negligibly-nontoxic fluid piping with design pressure less than or equal to 1.0MPa and design temperature higher -zo c but not higher than 185 C. 2.1.6 C-type fluid piping Incombustible, nontoxic or negligibly-nontoxic fluid piping excluding D-type fluid piping. 2.1.7 Pipework components The generic term of spare parts for forming piping system by connection or assembling, including piping components and pipe-supporting elements. 2.1.8 Piping components Pipework components used for connecting or assembling piping, including pipe, pipe fittings, flange, sealing element, fastener, valve, safety protection devices, expansion joint, flexible joint, pressure hose, steam trap, filter, throttling device and separator in piping, etc.. 2.1.9 Pipe-supporting elements Pipework components used to transmitting piping deadweight, conveyance fluid weight, load caused by operating pressure and temperature difference, and loads caused by vibration, wind force, earthquake, snow load, impact and displacement strain, including hanger rod, spring supporter/hanger, constant force supports/hangers, diagonal tie, balance weight, tightening bolt, brace strut, chain, guide 2
3 Basic Requirements 3.1 General Requirements 3.1.1 The construction organization undertaking industrial metallic piping engineering shall obtain corresponding construction qualification and conduct the corresponding piping installation within the qualification admission scope. The inspection organization shall obtain corresponding inspection qualification and conduct the corresponding piping engineering inspection works within its qualification admission scope. 3.1.2 The construction organization shall set up the quality management system on piping installation site, and develop sound quality control system and corresponding construction technology standards. 3.1.3 The personnel participating industrial metallic piping construction and quality inspection and testing shall have corresponding qualifications. 3.1.4 The following conditions shall be available before industrial metallic piping construction: 1 The engineering design drawing and the technical documents relevant shall be complete, and the design disclosure and drawing joint hearing have been conducted as required procedure. 2 The construction organization design or the construction scheme has been approved, and the technology and safety technical disclosure have been conducted. 3 The constructors has passes the examination as the relevant requirements. 4 The commencement documents have been transacted. 5 The machines, tools and instruments for piping installation shall be safe and reliable; the measuring devices shall be calibrated and run within the validity period. 6 The corresponding emergency plans for occupational health/safety and environment protection has been prepared well. 3.1.5 Before pressure piping construction, the construction organization shall transact written notice from the local quality and technical supervision department, and accept the supervision inspection of the supervision inspection organization. 3.1.6 Industrial metallic piping construction shall meet the requirements of the relevant current national standards on environment protection, safety technology and labor protection. 3.2 Grading 3.2.1 Industrial metallic pressure piping shall be divided into GC 1, GC2 and GC3 according to the relevant requirements of the national current standard "Pressure Pipe Safety Technology Supervision Regulation for Industrial Pressure Pipe" TSG DOOO 1. 3.2.2 The piping except pressure piping shall be classified as C-type fluid piping or D-type fluid p1p111g. 3.2.3 Where the piping conveys the mixed medium with different toxicity hazard degree or fire hazard, the grade of the piping shall be determined by the design document according to hazard degree and content of the medium. 6
4 Inspection of Pipework Components and Materials 4.1 General Requirements 4.1.1 The pipework components and materials shall have the manufacturer's product quality certification documents, and meet the requirements of the national current standard and the design document. 4.1.2 As for pipework components and materials, before use, the material, specification, type, quantity and mark hereof shall be checked according to the requirements of the national current relevant standard and the design document, and the results of appearance quality and geometric dimension inspection/acceptance, which shall be conducted, shall meet the requirements of the design document and corresponding product standard. The marks of pipework components and materials shall be distinct and complete, and by which the product quality certification document can be traced. 4.1.3 Where there is disagreement on the perfonnance data or the inspection result for pipework components or materials, the pipework components or materials of this batch shall not be used prior to the disagreement is settled. 4.1.4 Spectral analysis or other methods shall be applied to re-inspect the material of the piping components made of chrome molybdenum alloy steel, nickeliferous low-temperature steel, stainless steel, nickel and nickel alloy, and titanium and titanium alloy, and they shall be marked. 4.1.5 For the pipework components or material that are required to conduct low-temperature impact tenacity test by the design document, the supplier shall provide low-temperature impact tenacity test result document, and the test results shall not be lower than the requirements of the design document. 4.1.6 For stainless steel, Nickel and nickel alloy pipework components or material that are required to conduct intergranular corrosion test by the design document, the supplier shall provide intergranular corrosion test result document, and the test results shall not be lower than the requirements of the design document. 4.1. 7 The quality of the anti-corrosion lined pipes shall be inspected according to the requirements of the national current relevant standard. 4.1.8 Pipework components or material unqualified shall not be used and they shall be marked and isolated. 4.1.9 The pipework components and material shall be kept well in the construction process, and shall not be mixed or damaged. The marks hereof shall be distinct and clear. The pipework components and material made of stainless steel or nonferrous metal shall not be exposed onto carbon steel or low alloy steel during the transport and storage period. 4.1.10 The results for appearance quality and geometric dimension inspection and acceptance of pipework components shall be made "Record of inspection on piping components'', by the format specified in Table A.0.1 in this code. 4.2 Valve Inspection 4.2.1 Before installing, valves shall be inspected in appearance quality. They shall be complete; the 7