Seamless Steel Pipe(SMLS Pipe)
API 5CT Tubing, API 5CT Casing, For extracting oil and gas from wells
Pup joint is a pipe of non-standard length used to adjust the length of tubular strings to its exact requirement.
API 5DP Drilling, For well drilling
GB9948-1988 is for manufacturing of furnace tubes, heat exchangers and pipelines in refineries