... ,A,B,X42,X46,X52,X56,X60,X65,X70,X High Quality Carbon Steel Drill Pipe We can produced drilling pipe(API5D ... top quality in the world, such as hydraulic upset forging machine, walking beam quenching furnace,, hot and cold straighten device, friction welding ... pipe end, magnetic particle inspection, friction welding, seam inspection. We strictly carry out API spec Q1 quality control system and API Spec ...