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Drill collar is thick-wall tubular machined from solid steel bars and manufactured to meet and exceed API specifications. Drill collar, a major component of bottom hole assembly, is in the lowest part of the drill string. The main characteristic of drill collars with large wall thickness (generally is 38 to 53mm that is equivalent to the pipe wall thickness of 4-6 times), has much larger gravity and stiffness.
Drill collars can be divided into spiral drill collar, non-magnetic drill collar and integral drill collar.
The integral drill collar is smooth thick wall round pipe with threads on both ends.
The spiral drill collar is processed 3 right lateral spiral grooves on the surface of circular cylinder in order to reduce the contact area with borehole wall. This can effectively prevent the differential pressure sticking. The non-magnetic drill collar is mainly used in the process of oil drilling monitoring. The standard is N1310 low carbon alloy steel with good low permeability and machining performance.
Drill Collar Production Processes:
Drill collar is thick-wall tubular machined from solid steel bars and manufactured to meet and exceed API specifications. Drill collar, a major component of bottom hole assembly, is in the lowest part of the drill string. The main characteristic of drill collars with large wall thickness (generally is 38 to 53mm that is equivalent to the pipe wall thickness of 4-6 times), has much larger gravity and stiffness.
Drill collars can be divided into spiral drill collar, non-magnetic drill collar and integral drill collar.
The integral drill collar is smooth thick wall round pipe with threads on both ends.
The spiral drill collar is processed 3 right lateral spiral grooves on the surface of circular cylinder in order to reduce the contact area with borehole wall. This can effectively prevent the differential pressure sticking. The non-magnetic drill collar is mainly used in the process of oil drilling monitoring. The standard is N1310 low carbon alloy steel with good low permeability and machining performance.
Drill Collar Production Processes:
