Codes Vs Standards:
- Codes prescribes requirements for design, materials, fabrication, erection, examination, assembly, test, and inspection of piping systems, whereas standards contain design and construction rules and requirements for individual piping components such as elbows, tees, returns, flanges, valves, and other in-line items.
- Compliance to code is generally mandated by regulations imposed by regulatory and enforcement agencies. At times, the insurance carrier for the facility leaves hardly any choice for the owner but to comply with the requirements of a code or codes to ensure safety of the workers and the general public. Compliance to standards is normally required by the rules of the applicable code or the purchaser’s specification.
Recommended Practices, prepared by professional organisations or professional bodies are optional set of documents which can be used for good engineering practice.
Even though every country have their own codes and standards but still the American codes and standards are most widely used. The major codes and standards which are used in day to day piping application are listed below:
A. ASME CODES:
1.0 ASME B31: CODE FOR PRESSURE PIPING:-
ASME B31.3 – Process Piping:
This code normally provides rules for piping found in petroleum refineries, chemical,pharmaceutical,textile, paper, semiconductor, and cryogenic plants, and related processing plants and terminals including piping for fluids like raw, intermediate and finished chemicals, petroleum products, gas, steam, air and water, fluidized solids, refrigerants, cryogenic fluids etc. For process piping professionals this code is of atmost importance.
This Code does not provide information on the following:
(a) piping systems designed for internal gage pressures at or above zero but less than 105 kPa (15 psi), provided the fluid handled is nonflammable, nontoxic, and not damaging to human tissues and its design temperature is from −29°C (−20°F) through 186°C (366°F).
(b) power boilers and boiler external piping which is required to conform to B31.1.
(c) tubes, tube headers, crossovers, and manifolds of fired heaters, which are internal to the heater enclosure
(d) pressure vessels, heat exchangers, pumps, compressors, and other fluid handling or processing equipment, including internal piping and connections for external piping.
(e) piping covered by ASME B31.4, B31.8, or B31.11, although located on the company property
(f) plumbing, sanitary sewers, and storm sewers.
(g) piping for fire-protection systems
(h) piping covered by applicable governmental regulations
This code provides requirements for piping typically found in electric power generating stations, in industrial and institutional plants, geothermal heating systems, and central and district heating and cooling systems. This code is mainly important for Power piping professionals. It does not apply to piping systems covered by other sections of the Code for Pressure Piping, and other piping which is specifically excluded from the scope of this code.
ASME B31.4 – Pipeline Transportation Systems for Liquids and Slurries:
This code provides requirements for piping transporting liquids between production facilities, tank farm, natural gas processing plants, plants and terminals and within terminals, pumping, regulating, metering stations, and other delivery and receiving points.ASME B31.5 – Refrigeration Piping and Heat Transfer Components:
This code prescribes requirements for piping for refrigerants, heat transfer components and secondary coolants for temperatures as low as -320 degree F (-196 degree C)
ASME B31.8 – Gas Transmission and Distribution Piping Systems:
This code covers the piping transporting products that are mostly gas (Liquefied Petroleum Gas) between sources and terminals. This code also covers safety aspects of the operation and maintenance of those facilities.
ASME B31.9 – Building Services Piping
AMSE B31.11 – Slurry Transportation Piping Systems.
ASME B31.12 – Hydrogen Piping and Pipelines.
2.0 ASME BOILER AND PRESSURE VESSEL CODE:-
It contains 11 sections as mentioned below:
Section I Power Boilers
Section II Material Specifications
Section III Rules for Construction of Nuclear Power Plant Components
Section IV Heating Boilers
Section V Nondestructive Examination
Section VI Recommended Rules for Care and Operation of Heating Boilers
Section VII Recommended Rules for Care of Power Boilers
Section VIII Pressure Vessels
Section IX Welding and Brazing Qualifications
Section X Fiber-Reinforced Plastic Pressure Vessels
Section XI Rules for In-Service Inspection of Nuclear Power Plant Components
Out of this 11 sections Section VIII is very important for Process Piping engineers.
B. PIPING COMPONENT STANDARDS: The major piping component standards which are used frequently are listed below:
ASME B36.10M: Welded and Seamless Wrought Steel Pipe
ASME B36.19M: Stainless Steel Pipe
ASME B16.9: Factory-Made Wrought Steel Buttwelding Fittings
ASME B16.5: Pipe Flanges and Flanged Fittings
ASME B16.11: Forged Fittings, Socket Welding and Threaded
ASME B1.1: Unified Inch Screw Threads
ASME B16.20: Metallic Gaskets for Pipe Flanges.
ASME B16.25: Buttwelding Ends
ASME B16.10: Face-to-Face and End-To-End Dimensions of Valves
MSS SP-58: Pipe Hangers and Supports — Materials, Design, and Manufacture.
BS 6501, Part 1: Flexible Metal Hose
NFPA 1963: Standard for Fire Hose Connections
Refer ASME code B 31.3 for more of the component standards
C. ASTM STANDARDS:
The American Society for Testing and Materials (ASTM) is a scientific and technical organization that develops and publishes voluntary standards on the characteristics and performance of materials, products, systems, and services. The standards published by theASTM include test procedures for determining or verifying characteristics, such as chemical composition, and measuring performance, such as tensile strength and bending properties. The standards cover refined materials, such as steel, and basic products, such as machinery and fabricated equipment. The standards are developed by committees drawn from a broad spectrum of professional, industrial, and commercial interests. Many of the standards are made mandatory by reference in applicable piping codes.
The major ASTM standards are listed below:
A36: Carbon Structural Steel
A105: Carbon Steel Forgings, for Piping Applications
A106: Seamless Carbon Steel Pipe for High-Temperature Service
A312: Seamless, Welded, and Heavily Cold Worked Austenitic Stainless Steel Pipe
A335: Seamless Ferritic Alloy Steel Pipe for High-Temperature Service
A358: Electric-Fusion-Welded Austenitic Chromium-Nickel Alloy Stainless Steel Pipe for High-Temperature Service and General Applications
A516: Pressure Vessel Plates, Carbon Steel, for Moderate and Lower-Temperature Service
A671: Electric-Fusion-Welded Steel Pipe for Atmospheric and Lower Temperatures
A672: Electric-Fusion-Welded Steel Pipe for High-Pressure Service at Moderate Temperatures
Suggested reading for more on ASTM standards: Refer ASME B 31.3 Specification index for Apeendix A.
D. API STANDARDS:
The American Petroleum Institute (API) publishes specifications, bulletins, recommended practices, standards, and other publications as an aid to procurement of standardized equipment and materials.
The major ones are listed below for your reference:
API RP 520: Recommended Practice for Sizing, Selection,and Installation of Pressure-Relieving Devices in Refineries.
API 610: Centrifugal Pumps for Petroleum, Petrochemical and Natural Gas Industries
API 650: Welded Tanks for Oil Storage
API 661: Air-Cooled Heat Exchangers for General Refinery Service
API 560: Fired Heaters for General Refinery Service
API 617: Axial and Centrifugal Compressors and Expander-compressors for Petroleum, Chemical and Gas Industry Services
API 618: Reciprocating Compressors for Petroleum, Chemical, and Gas Industry Services
API 612: Petroleum, Petrochemical and Natural Gas Industries-Steam Turbines-Special-purpose Applications
For more API Standards refer the API website for their catalogue of published standard.
There are several other codes and standards which are used in piping industry like AMERICAN WATER WORKS ASSOCIATION, AMERICAN WELDING SOCIETY, AMERICAN SOCIETY OF SANITARY ENGINEERS, AMERICAN SOCIETY OF CIVIL ENGINEERS, AMERICAN SOCIETY FOR NONDESTRUCTIVE TESTING, AMERICAN IRON AND STEEL INSTITUTE, EXPANSION JOINT MANUFACTURERS ASSOCIATION, MANUFACTURERS STANDARDIZATION SOCIETY OF THE VALVE AND FITTINGS INDUSTRY, NATIONAL FIRE PROTECTION ASSOCIATION, TUBULAR EXCHANGER MANUFACTURERS ASSOCIATION etc.
Also there are non american standards like BRITISH STANDARDS AND SPECIFICATIONS, RUSSIAN CODES, DIN STANDARDS AND SPECIFICATIONS, JAPANESE STANDARDS AND SPECIFICATIONS, ISO STANDARDS AND SPECIFICATIONS etc. User is requested to venture more of these standards in his own interest. Few of the Russian codes are listed below:
GOST 32388-2013 Process Piping Stress Analysis, GOST 32569-2013 Process Piping Design-
These codes provide requirements for process piping design and analysis. GOST 23388-2013 Code covers such aspects as vacuum piping stability, creep in high temperature piping, cryogenic piping stress analysis requirements, seismic analysis, HDPE piping stress analysis
RD 10-249-98 – Power Piping. Design and Stress Analysis
This code provides requirements for piping typically found in electric power generating stations, in industrial and institutional plants, geothermal heating systems except district heating systems.
GOST R 55596-2013 District Heating Systems Stress Analysis, SP 124.13330.2012 District Heating Systems Design
This code provides requirements for buried and above ground district heating piping systems design and analysis.
SP 36.13330.2012 – Gas and Oil Transmission Piping Systems. Design and Stress Analysis
This code provides requirements for pipelines transporting gas and oil between production facilities, tank farm, natural gas processing plants, plants and terminals and within terminals, pumping, regulating, metering stations, and other delivery and receiving.
GOST 34347-2017 Boiler and Pressure Vessel Code Design Requirements,
GOST 34233-2017 Boiler and Pressure Vessel Code Stress Analysis Requirements
GOST 34233.1-2017: General requirements
GOST 34233.2-2017: Cylindrical and conical shells, convex and flat bottoms and covers
GOST 34233.3-2017: Reinforcement of openings in shells and bottoms under internal and external pressure. Strength calculation of shells and bottoms under external static loads on the nozzle
GOST 34233.4-2017: Strength and leak-tightness calculation of flange joints
GOST 34233.5-2017: Calculation of shells and bottoms under Influence of support loads
GOST 34233.6-2017: Strength calculation under low-cyclic loads
GOST 34233.7-2017: Heat-exchangers
GOST 34233.8-2017: Jacketed vessels
GOST 34233.9-2017: Vertical Column Vessels
GOST 34233.10-2017: Vessels involving hydrogen sulphide media
GOST 34233.11-2017: Method of strength calculation of shells and bottoms according to weld misalignment, angular misalignment and shell no roundness
GOST 34233.12-2017: Requirements for representation of the strength calculations carried out on the computer
Piping Component Standards:
Pipes: GOST 10705, 10706, 11068, 2095, 3262, 550, 8696, 8731, 8733, 9940, 9941, 53383, OST series 108x, 34x, TU 14-3-1080, 14-3-1128, 14-3-1160 and lots of other standards
Bends: GOST 17375, 30753, OST series 108x. 34x and lots of other standards
Tees: GOST 17376, OST series 108x. 34x and lots of other standards
Flanges: GOST 33259 and lots of other standards