Selection of thread types for the inlet and outlet ports of fixed-pressure vessels
Thread Content
For the inlet and outlet ports of fixed-pressure vessels, should threads of type G or Rp be used? What is the purpose of each type, and under what circumstances should they be chosen?
They are all pipe threads; G denotes the British standard cylindrical pipe thread for non-sealing purposes, while Rp denotes the British standard cylindrical pipe thread for sealing purposes, with Rp being the more common one.
For general sealing threads, R threads are used, with standard codes GB/T7306.1~GB/T7306.2-2000; or NPT threads, with standard code GBT 12716-2002. The G thread is a non-sealing thread; a sealing gasket is required to achieve sealing.