6-3/4" Drill String Components , DC Spiral Drill Collars NC Joint

API 7-1 Spec 6-3/4" AISI 4145H Spiral DC Drill Collar For Oil Well Drilling

Drill collars are extra-heavy integral tools used to concentrate weight onto the drill bit so as to produce sufficient force for the drill bit to break rock efficiently while drilling. They are made of AISI 4145H or 4145H modified steel and are connected between drill pipes and drill bits.

Our drill collar connections comply with dimensional requirements specified in API Spec 7-1. Drill collars also come with slip and elevator recesses for safe and efficient handling. Slip and elevator recesses can be used together or separately.

A. Slick Drill Collar

Note: 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. The Drill collar are manufactured strictly from API Spec7-1 and SY5411 standard.

B. Spiral Drill Collar

Note: Spiral drill collar is used to reduce contact area with hole so as to avoid efficiently bit sticking from diffirential pressure. The drill collars are manufactired strictly according to API Spec7-1 and Standard SY5144

C. Spiral Drill Collar With Elevator Groove And Slip Groove

Note: 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 SPEC7-1. Hardbanding is optional at customers’ requests.

D. Non-magnetic Drill Collar

The as cold rooled finish on both ID and OD surface with unique technical process strengthen the structure and ensures the tools with optimal resistance to stress,corrosion,cracking and the mechanical performance is greatly enganced.

Hot sale API standard drill collar for oil well