JIC 37° to NPT Adapter

The JIC 37° to NPT adapter allows a hose or tube with a JIC 37° connection to be fitted to an NPT-threaded port. The port side has a tapered male NPT thread per ASME B1.20.1, and the line side has a UNF male thread with a 37° flare seat. On the NPT side, sealing is achieved by tapered thread engagement and thread sealant; on the JIC side, by metal-to-metal seating on the 37° cone.

It is common on US-made pumps, valves and test equipment, on hydraulic test benches, in maintenance units for defense vehicles and in aviation ground support equipment (GSE). It is a practical way to move the line standard to JIC without changing the port on existing equipment.

• The NPT end must be fitted only into a female NPT port; fitting it into a BSPT port causes leaks and thread damage because of the 55° / 60° thread angle difference.
• On high-vibration lines, a UNF port connection with O-ring sealing may be more reliable than a tapered thread.
• The thread and cone size of the JIC end must be verified together with the size of the mating part.

Installation note: First tighten the NPT end into the port with thread sealant, taking care that the sealant does not spread past the first threads into the line. Connect the JIC side while the cone surfaces are clean.