Male Stud Elbow (NPT)

A male stud elbow connects tube to an equipment port at a 90° angle. The tube end has a 24° cone, a ferrule and a nut; the port end has an NPT tapered male thread to ASME B1.20.1. With NPT threads, sealing is achieved by 1:16 tapered thread engagement and a thread sealant.

It is used in ship engine rooms with US-made pumps, valves and power units, on equipment on offshore platforms, on imported machines in paper and board mills, and in aviation test equipment, wherever the tube must change direction immediately in front of the port.

• NPT (60°) and BSPT (55°) threads look similar but are not interchangeable; forcing them together permanently damages the thread.
• On a tapered thread, the final position is determined by tightening until a seal is achieved, so the elbow may not stop at the desired orientation. If orientation is critical, consider adjustable types with a parallel thread and O-ring on the port end.
• Use a suitable thread sealant paste to counter the risk of galling on stainless-to-stainless threads.

Installation note: Do not back off when setting the elbow orientation, as this compromises the seal. Reach the orientation in the forward tightening direction.