Specification for 10,000 PSI Working Pressure Threaded Pipe Fittings
Kindly supplied by Prochem
Scope
This specification covers 10,000 PSI working pressure screwed pipe fittings manufactured in accordance with the design and material requirements as listed in the following clauses.
Reference documents
ASTM Standards:
- A182/A182M Specification for Forged or Rolled Alloy-Steel Pipe Flanges, Forged Fittings, and Valves and Parts for High - Temperature Service.
- A276 Specification for Stainless and Heat-Resisting Steel Bars and Shapes.
- A479/A479M Specification for Stainless and Heat-Resisting Steel Bars and Shapes for Use in Boilers and Other Pressure Vessels.
ANSI/ASME/SAE Standards:
- ANSI/ASME B1.20.1 Pipe Threads, General Purpose (Inch)
- ASME B31.3 Chemical Plant and Petroleum Refinery Piping.
- SAE J1065 Pressure Ratings for Hydraulic Tubing and Fittings.
Materials
The fittings shall be machined from stainless steel Grade 316 material. The material shall be covered by either of the following specifications: ASTM A182/A182M, A276, A479/A479M or an approved equivalent.
Design criteria
All fittings supplied under this specification shall be designed using the Barlow Formula as stated in SAE J1065.
Male threaded fittings shall be designed with a factor of Safety 4;1(Dimension affected is the outside diameter or across the flat of the hexagon at the weakest inside diameter).
The 10,000 PSI working pressure shall be based on the operating temperatures of -29 Deg C. to 150 Deg C. as allowed in ASME B31.3.
Threads
All fittings supplied under this specification shall be in accordance with ANSI/ASME B1.20.1 NPT (National Pipe Taper) Pipe Threads General Purpose (inch).
Thread tolerances
NPT threads shall meet the dimensional requirements stated in ANSI/ASME B1.20.1 with the following exception.
The L1 thread gauging requirements shall be as stated below.
- Gauging Eternal taper threads with Ring Gauges (Male Threads).
When hand tight the plug gauge must engage into female fitting +1/4 to +1 turn below the start of the first scratch mark on the chamfer zone.
Note: the gauge is to be turned towards the body of the fitting.
- Gauging Internal Taper Threads with Plug Gauge (Female Threads)
When hand tight the plug gauge must engage into the female fitting +1/4 to +1 turn below the start of the first scratch mark on the chamfer zone.
Note: the gauge is to be turned towards the body of the fitting.
Marking
Fittings supplied under this specification shall have the following marking requirements. When the shape or the small size of the fitting does not permit the inclusion of all the required markings, they may be omitted in the following order.
- Manufacturer’s name or trademark,
- Size designation,
- Thread designation,
- Rating designation in either PSI or Kpa,
- Melt (heat) identification or traceability number,
- Material designation.
Certification
Original Mill Certificate or an authorized certificate stating the chemical, mechanical and physical properties of the base material, which has been transferred exactly from the original mill certificate.