drill collar

详情

Drill Collar is mainly used to provide bit weight to drill bit so that drill pipe is in tension. Especially drill collar can keep drill bit centralized and hole track by large rigidity.

Spiral Drill Collar is used to reduce contact area with hole so as to avoid efficiently bit sticking from differential pressure. TIANHE brand spiral drill collars are manufactured strictly according to API Spec**1 and Standard SY***4.
 

Elevator groove and slip groove made on box thread face of slick drill collar or spiral drill collar can be used as lifting sub and safety slip when trip out. The technical parameters for elevator groove and slip groove is as per API spec**1. Hard banding is optional at customers requests.