Drill Collar

We provide full range of slick drill collars, spiral drill collars and non-magnetic drill collars, the sizes are available from 3-1/8 to 11 inches



Drill collars are manufactured from AISI 4145H modified steel which are trepanned and drifted according to API Spec 7 while the Non-magnetic drill collars are made from chrome-manganese low carbon alloy or Monel alloy.

Full-length heat-treatment processes ensure that mechanical properties meet or exceed API Spec 7 requirements. Drill collar material and process traceability are maintained from receipt of mills’ certified raw material to completion of all the manufacturing. Serial numbers are die stamped on bar bodies. Drill collar thread roots, as well as elevator recess upper radius, are cold-rolled. Cold rolling creates a compressive recess upper radius stress condition that increases fatigue life by minimizing crack initiation. All tool joint connections are phosphate-coated or copper plated to improve resistance to corrosion. Optional slip and elevator recesses to improve handling efficiency and safety are also available.