Drill collars are available in lengths from 10 feet to 30 feet with 3-1/2"to 11" external diameter.

Our drill collar are made of AISI 4145H modified alloy steel and adopt medium frequency inductance heating method for hardening and tempering,during which steel parts rotate continuously to get even heating.Production process strictly follow SY/T5144-1997 and API Spec 7 requirements.We have different sizes of drill collar,the length could be 10 feet to 30 feet with 3-1/2"to 11" external diameter.We can supply drill collar according to customer specifications.If any of the items meet your interest,please feel free to contact us,we will reply you the first time.

drill collar