Classification: Mainly internal thread pipe, external thread pipe, flexible pipe joint, elbow pipe (elbow), tee pipe, cross pipe (cross head), reducer pipe, etc.
Manufacturing standards include GB/T 14383, ASME B16.11, BS 3799, MSS SP 83.
According to the material, it can be divided into carbon steel pipe fittings, stainless steel pipe fittings, alloy steel pipe fittings, etc.