Answer
Mar 13, 2026 - 12:13 PM
A male NPT (National Pipe Tapered) fitting can technically be mated with a female NPSM (National Pipe Straight Mechanical) thread, but it is not a recommended or reliable connection for high-pressure systems. The connection relies on the tapered male thread tightening into the straight female thread, often requiring sealant. While the threads may engage, they are not strictly designed to be compatible. Forcing an NPT fitting into an NPSM fitting can damage the threads. Due to the difference in taper vs. straight threaded - NPT and NPSM are generally incompatible due to their different thread forms. We would recommend using an adapter with female NPT x female NPSM threads to make a safe and proper connection. Our offering can be found here for the female NPT x NPSM female swivel adapters.
