1. For tube casings and couplings 2. Multi-tooth thread, 8API ... solution to oil and gas industry at home and abroad for many years. SMT carbide API threading inserts are in multi- ... and buttress threads, 3,4,5,8,10 TPI available for cutting J55, L80, L80, and P110. Any special thread ... forms with drawings and samples are also welcome. For more information, you are very welcome to contact us ...