Socket Weld Full Coupling
Our socket weld full coupling is one-piece hot forged straight fitting with double socket weld ends, used to connect two equal-diameter small-bore pipes. Manufactured strictly per ASME B16.11 & MSS SP-79 standards, all sizes keep full nominal dimension without minus tolerance, widely applied for power, chemical, hydraulic and fire protection high-pressure pipelines.
For high-pressure pipeline transition and termination needs, you may also check our Reinforced Swage Nipple for size reducing connection and Butt Weld Pipe Cap to seal the pipe end.
Overview Of Socket Weld Coupling
Socket Weld Full Coupling is a forged double-socket straight pipe fitting, equipped with two identical socket weld ports to connect two same-size pipes end to end, realizing straight pipeline extension.
Integrally hot forged from carbon steel A350 LF2 / A105, stainless steel A182 F304/F316L optional. Thick uniform wall greatly improves pressure bearing capacity. We strictly control OD, ID and wall thickness, guarantee zero minus tolerance without thin-wall cutting corners. Three standard pressure classes: Class3000, Class6000, Class9000 to satisfy various high-pressure working conditions.
Core Key Features Of Socket Weld Coupling
- One-piece hot forging integrated forming, high tensile strength and impact resistance
- Double equal socket weld ends, convenient butt welding, tight sealing under high pressure
- Main raw material: Carbon Steel A350 LF2 / A105; Stainless Steel A182 F304/F316L for corrosive media
- Fully comply with international standards ASME B16.11 & MSS SP-79
- Complete size coverage: DN6 ~ DN100 (1/8″ ~ 4″)
- Zero minus tolerance on all dimensional parameters, full standard nominal size
- Smooth inner hole surface, low fluid resistance, no flow dead zone
- Full MPI magnetic particle testing & hydrostatic pressure test before shipment, complete MTC material test certificates provided
Technical Specification
| Item | Technical Parameter |
| Product Name | Socket Weld Full Coupling / Straight Coupling |
| Connection Type | Double Socket Weld (SW) Ends |
| Production Craft | Hot Forged One-Piece Integral Forming |
| Executive Standard | ASME B16.11, MSS SP-79 |
| Available Materials | Carbon Steel A350 LF2, A105; SS A182 F304 / F316L Optional |
| Pressure Class | Class 3000, Class 6000, Class 9000 |
| Size Range | DN6 ~ DN100 / 1/8″ ~ 4″ |
| Wall Schedule | Sch80, Sch160, XXS, Custom wall thickness |
| Structure Type | Full Coupling (Double Socket) |
| Dimensional Tolerance | Full standard nominal size, zero minus tolerance |
| Inspection Items | MPI Magnetic Particle Test, Hydrostatic Test, Full Dimension Inspection |
| Surface Treatment | Black anti-rust paint (Carbon Steel); Pickling & Passivation (Stainless Steel) |
Applications
- Thermal power plant instrument control pipelines
- Petrochemical & refinery high-pressure process pipelines
- Hydraulic equipment high-pressure transmission piping
- Fire protection small-bore pressure pipelines
- Offshore marine low-temperature anti-rust piping (A350 LF2 low temperature steel)
- Oil & gas field measuring instrument auxiliary piping
- Food & pharmaceutical stainless steel clean pipelines
Why Choose Our Socket Weld Full Coupling
- Direct forged fitting factory supply, stable stock & competitive ex-work factory price
- All couplings produced to full standard dimensions with zero minus tolerance, never cut corners with thin walls
- Regular common sizes in stock, fast delivery within 7–15 working days
- Custom special sizes, wall thickness and surface treatment supported based on customer drawings
- Complete export certification package: Material Test Certificate (MTC), MPI NDT report, dimensional inspection sheet
- Standard export wooden case packaging, avoid scratch, rust and deformation during long-distance sea transport
