It is a 3-piece flat seat union with butt weld ends on both sides. The sealing relies on compressing a PTFE gasket between two flat mating faces at the union centre. The two welding spigots will be butt-welded onto stainless steel pipes, while the union nut allows easy disassembly for maintenance without cutting the pipeline again.

Standard butt weld ends comply with ISO 1127 / EN 10217, DIN, or ASME B36.19. We can match OD and wall thickness to your pipe schedule (Schedule 10, Schedule 40, etc.). Socket weld (SW) version is also available on request. Please confirm pipe OD, wall thickness and standard before order.

Standard grades:
– 304 / CF8
– 316 / 316L / CF8M (1.4408, preferred for marine, chemical, chloride environment)
Special duplex or alloy material available by custom inquiry.

Normally manufactured to ISO4144, rated **150LB / PN20**.
PTFE gasket working range: **-20°C ~ +120°C**.
Pressure will derate when temperature rises. For higher temperature service, RPTFE gasket is an alternative option.

BSPT, BSPP (G), or NPT standards are supported. Please specify the required thread type when placing an order.

Union Welding PTFE has **butt weld spigot ends to weld with pipe**. Union Flat PTFE FF has female thread ends to screw onto threaded pipe.
The central flat PTFE sealing structure is the same for both; but the end connection cannot be interchanged.

Yes, each complete union is supplied with one matched PTFE gasket. Spare PTFE gaskets can be purchased separately. We suggest replacing the gasket after repeated disassembly to avoid leakage.

Answer: The standard finish is a pickled matte surface. Other options include a satin finish or a mirror-polished finish suitable for sanitary/hygienic applications.

1. Weld the two spigot ends to pipes first, make sure the flat sealing faces are clean, flat and free of welding spatter.
2. **Do NOT apply PTFE tape or sealant on the central flat sealing face**.
3. Tighten the hex union nut evenly with controlled torque, only to compress the PTFE gasket properly. Over-tightening may deform the gasket and cause leak.

Small-batch orders are accepted, and a single order may include products of different specifications.

Typically, shipments are dispatched within 7–15 days of receiving the deposit, depending on the order quantity.

Raw material inspection → CNC machining → Thread inspection → Hydrostatic testing → Visual inspection → Final dimensional verification before packaging.

We offer FOB (Free On Board) terms, with the shipment originating from a Chinese port. We will provide a commercial invoice, packing list, and bill of lading for import customs clearance.

We offer FOB (Free On Board) or CIF (Cost, Insurance, and Freight) terms, with shipments originating from a Chinese port. We will provide a commercial invoice, packing list, and bill of lading for customs clearance.

Please provide photos, videos, and inspection records. We will assess the root cause; depending on the contractual terms, solutions may include product replacement, a partial refund, or a reshipment.”