... ",5",5-1/2"oil drilling pipe :-Drilling pipe,heavy weight drilling pipe,tubing pipe,casing pipe. We can produced drilling pipe(eu,iu ieu ... on weld seam linearity testing and visual inspection1) Certificate: API 5DP-0002,API Q1-0964, ISO 9001,ISO 14001,OHSAS 180012) ... and inspected with API Spec standard thread gauges. To improve the galling-resistance during initial break-in and drilling operation, all ...