Socket Welding Coupling is a type of pipe fitting commonly used in high pressure piping systems. It is designed to join two pieces of pipe together through welding. The coupling is cylindrical in shape with one end machined into a groove for fitting the pipe and the other end for welding. Common materials used to manufacture couplings include stainless steel, carbon steel, and alloy.

Applications

• Oil and Gas Systems: Socket Welding Coupling is commonly used in oil and gas systems due to its high pressure resistance and durability.
• Chemical industry: Due to its ability to withstand corrosive chemical environments, couplings made of stainless steel are often used in this industry.
• Water supply and wastewater treatment systems: Coupling is also applied in water supply and wastewater treatment systems, ensuring the safety and durability of the system.
• Power Industry: In power plants, Socket Welding Coupling is used in high pressure steam and water piping systems.

Standards

ASME B16.11: This is the primary standard for socket weld and threaded fittings, including dimensions, tolerances, wall thicknesses, and quality control and inspection requirements.

• NPS (Nominal Pipe Size): 1/8″ to 4″
• Outside Diameter (OD): Depends on nominal pipe size and manufacturer’s standard.
• Wall thickness of coupling: must be sufficient to withstand the pressure and temperature of the system. For example: 1/2″ coupling has a wall thickness of approximately 3.73 mm (Schedule 40) or 4.78 mm (Schedule 80)
• Diameter tolerance: The inner and outer diameters of the coupling have specified tolerances to ensure a tight fit between the coupling and the pipe.
  • Inside diameter (ID): ±0.10 mm to ±0.25 mm
  • Outside diameter (OD): ±0.15 mm to ±0.30 mm
  • Length tolerance: ±1.6 mm
• Material: Carbon steel, stainless steel, alloy steel, copper and copper alloy, nickel alloy, aluminum, plastic, special alloy.

Socket Welding Coupling size and thickness table