NPT are common threads used for general purposes, while FPT are a type of NPT. NPTs and FPTs are used to join pipes and fittings for all types of general purposes. This includes things such as joining low pressure air or liquid needs. They are also used for many mechanical applications.What is the difference between NPT and NPTF?
NPT stands for National Pipe Taper. For NPT, pipe should be thread per ANSI B1.20.1. For the National Pipe Tapered for Fuels, or NPTF, the pipe should be thread as per ANSI B1.20.3. Differences in NPT and NPTF threads lie in the major and minor diameters, as well as the root and crest of the threads.Will NPTF fit NPT?
NPTF threads will screw together with NPT threads and should have no noticeable assembly problem. There will most likely be an interference fit between the root and crest on either the major or minor diameter of the thread , depending on which part is NPTF.Is BSP and NPT the same?
BSP – British Straight and Tapered. It is not recommended to cross fit different types of thread, even if the threads per inch are the same. The reason being that the thread designs are different, NPT is a sharp thread and BSP is a rounded thread. ISO threads have 55o taper angle versus 60o for NPT.