Views: 5 Author: Site Editor Publish Time: 2023-11-20 Origin: Site
ASTM A234 butt welding pipe fittings are an important type of pipe connection fitting that uses welding to connect pipes together, and are suitable for high-temperature and high-pressure working environments.They are often used in pipeline systems with long runs that do not require frequent disassembly.
What Is ASTM A234 Standard
ASTM A234 is a material standard developed by ASTM International, which specifies the chemical composition, mechanical properties, heat treatment, impact testing, and other aspects of carbon steel and alloy steel butt welding fittings.It covers steel fittings of seamless and welded types.
They are available in latest revision of ASME B16.9, B16.11, MSS-SP-79, MSS-SP-83, MSS-SP-95, and MSS-SP-97. Also widely used in pressure piping and in pressure vessel fabrication for service at moderate and elevated temperatures. The grades are ASTM A234 WPB, WPC, WP5, WP9, WP91, WP11, WP12 and WP22.
The Types Of ASTM A234 Butt Welding Fittings
According to Shapes：butt welding fittings include 90degree elbow, 45degree elbow, tee, cross, cap, concentric reducer, eccentric reducer, stub end, etc.These fittings can meet different pipeline layout and connection requirements.
According to Materials：ASTM A234 butt welding fitings include WPB、WPC、WP5、WP9、WP11、WP12、WP22、WP91、WP92、WP911、WP115,etc.It can adapt to the needs of pipeline applications in different working environments.
ASTM A234 WPB Butt Welding Fittings
ASTM A234 WPB is a commonly used carbon steel material in butt welding pipe fittings, with excellent low-temperature toughness, corrosion resistance, and high-temperature strength.It is mainly used in the manufacture of high-pressure valves, pipe fittings, chemical equipment, and other fields.
What Is WPB Meaning?
W = WELDABLE / wrought
P = RELATED TO P NUMBER OF ALLOY MATERIAL
B = REFER TO MINIMUM YIELD OF MATERIAL。
ASTM A234 butt welding fittings after shaping from an elevated temperature, shall be cooled down to a temperature below critical range under suitable conditions which preventing injurious defects caused by too rapid cooling, but in no case more rapidly than the cooling rate in still air. Referring standard in Section 7 of ASTM A960/A960M.
For Carbon Steel Grades ASTM A234 WPB, WPC, WPR
Hot formed WPB, WPC, WPR fittings forming at above 620℃[1150℉] to 980℃[1800℉] no need to be heat treated which they are cooled in still air.
Hot formed or forged WPB, WPC, WPR fittins made at above 980℃[1800℉] shall be annealed, normalized, or normalized and tempered. NPS4 hot forged fittings no need to be heat treated.
Fittings over NPS12, produced by locally heating a portion of the fitting stock to any temperature for forming, shall be annealed, normalized, or normalized and tempered. And these fittings inlcudes elbow, tee, reducers, the carbon content shall les than 0.26%. NPS12 under no need to be heat treated under this forming process.
Cold formed fittings, below 620℃[1150℉], shall be normlized or stress relieved at 595 to 690℃[1100 to 1275℉].
Fittings produced by fusion welding and wall thickness at welded end of 3/4 in [19mm] or bigger shall be post-weld heat treated at 595 to 675℃[1100 to 1250℉].
Manufacturing Process And Advantages
The manufacturing processes for butt welding fittings includes forging and shaping operations.As well as pressing, hammering, piercing, extruding, upsetting, rolling, bending, fusion welding and machining.Or the processes of combination of two or more of these operations.
Preparation of raw materials--Cutting and processing--Heat treatment--Surface treatment--Quality inspection--Packaging
Good cost performance