... ,A,B,X42,X46,X52,X56,X60,X65,X70,X High Quality Carbon Steel Drill Pipe We can produced drilling pipe(API5D ... welding, seam inspection. We strictly carry out API spec Q1 quality control system and API Spec 5DP production standard. We have a complete ... on weld seam linearity testing and visual inspection1) Certificate: API 5DP-0002,API Q1-0964, ISO 9001,ISO 14001,OHSAS 180012) OD ...