TIANHE, a manufacturer of high-quality spiral drill collars, produces its DRILL COLLAR from AISI 4145H modified quenched and tempered steel. Each drill collar is heat treated along its entire length for uniform toughness and durability. Strict metallurgical tests are performed per specifications to ensure the heat treatment produces consistent and maximum hardness through the depth of the bar.

Features and Benefits

• A hardness range of 285 to 341 BHN and a Charpy impact value of 40 ft-lbs are guaranteed for evenly distributed 16 points in any cross sections at room temperature;

• Connections are phosphate coated after machining to protect the threads from corrosive elements and to prevent galling upon initial make-up;

• Thread roots are cold rolled on API and H-90 connections;

• Pressed steel thread protectors are supplied for all drill collar units equipped with standard connections.

When ordering please specify

• Drill collar OD and ID;

• Overall length;

• Connections required (size and type);

• Special features desired, for example: Slick or Spiral (drill collar with spiral grooves); Stress Relief Features; Slip and/or Elevator Recess; Hardbanding. As trusted spiral drill collar manufacturers, we ensure every DRILL COLLAR meets the highest standards.