This means a 45-degree male fitting may thread into a 37-degree female, but they won’t seal correctly. Beyond making certain the cone-angles of fittings match, don’t over-tighten flared fittings.

It was originally published Oct. 21, 2004. Using the correct thread is critical for proper mating and replacing hydraulic fittings. First and foremost, it is a safety issue.

Section 500.8 focuses on equipment. As per 500.8 (E) (1), "For equipment provided with threaded entries for NPT threaded conduit or fittings, listed conduit, conduit fittings, or cable fittings shall ...