Our drill collar is made of 4145H Modified CrMo alloy steel. It is strict according to API Spec. 7 and SY/T5144. All threads are phosphated, copperized or cold worked. All connections are equipped with pressed steel thread protectors.
If you want to order this kind of products pls offer below information to us:
On enquiries and orders, please specify:
Slick or spiral;
Drill collar OD;
Drill collar bore:
Length of drill collar;
Connection type;
Drill collar is specilize used in oil field, with higher quality and competitive price, we have exported to many foreign countries. If you need pls free to contact with me.