Drill collars we produce is made from 4145H forging or rolling modified steel. We manage our Production and Inspection Process strictly according to API SPEC 7 requirements. All connections are phosphate-coated to improve resistance to corrosion. We can also do copper plating according to clients' requirements. We offer slip groove, elevator groove to improve handling efficiency and safety. We can also make stress relief groove according to clients' requirements. We provide free thread protector for both pin and box.

Different sizes we produce is from 3 1/2" to 11", our strength is large size like above 9" and small size like below 4 3/4".

Shenlong promises our product with superior quality, long life, short delivery time and competitive price.

Welcome your enquiry any time!