Weigao offers a wide variety of drill collar sizes from 3 ¨û¡± - 9 ¨ö¡±, spiraled or slick, and with api connections. All our drill collars are tailored to your specific requirements. We supply slick, spiral, and non-magnetic drill collars; their sizes are from 3-1/8 to 11 inches. Weigao drill collar are high quality products which meet the hardest operating conditions. Each collar undergoes strict quality control, more than one hundred checks are made in the course of manufacturing. All mechanical properties meet or exceed the requirements of api spec.7-1 for drill collars. Weigao drill collars are made of aisi 4145 h modified alloy steel or non-magnetic material. Other grades are available on request. Weigao drill collars are used successfully for sour gas wells. After forging or rolling, the bars are peeled, heat treated, stress relieved, ultrasonically inspected and straightened to api specifications, to ensure that each bar will meet the physical properties. Bundles , all connections shall be equipped with pressed steel or plastic steel thread protectors.
