Dowty Sealing Washer for BSP Ports

If your BSP fitting or port does not have a sealing flare or O-ring chamfer, you should use a Dowty Sealing Washer to seal the connection at the face of the female port.

Dowty Washers are comprised of a flanged nitrile (NBR) rubber insert bonded to the inside of a thick, zinc-plated steel washer. The rubber insert is molded to stand slightly proud of each side of the washer to ensure a good seal. The washer prevents the seal from getting crushed or extruding outwards, which makes them re-usable. Fluid pressure inside the joint simply forces the lip of the rubber insert tighter against the sealing surfaces. Recommended maximum working pressure* 2250 psi. Operating temperature range -4°F to 230°F (-20°C to 110°C).

If your male fitting has a concave flare at the end and the female has a matching convex flare, no sealing washer should be used. If the female port has a chamfer, use one of our BSP O-Ring Seals (Part No. 3243-Size) instead.

Note: BSP nomenclature can be confusing because the nominal size refers to the inside diameter of a cast iron pipe, not the outside diameter of the threads. If you are not sure what size you need, check in our Threaded Fitting Guide.

* Recommended working pressure is based on a 5 to 1 safety margin.