-
Drill Pipe
View Products
Heavy Weight Drill Pipe
View Products
Drill Collar
View Products
Kelly
View Products
Tool Joint
View Products
Surface Protection & Internal Coating
View Products
Specialty Drill Products
View Products
-
-
-
-
What You Must Know about Drilling Tool Combinations
Author:
Longway Petroleum
Source:
Published:
2026-07-06
Drill column is the general name of all downhole drilling tools from square drill pipe to drill bit, which consists of square drill pipe, drill pipe, drill collar, stabilizer joint and various other accessories. The function is to "lower the drill bit, transfer the mechanical energy needed to break the rock to the drill bit, apply drilling pressure to the bottom of the well, deliver the well washing fluid to the well and perform other downhole operations.
Working condition of the drilling column
During the drilling process, the drill column works alternately in two processes: start-up and normal drilling. During start-up, the drill column is under tension; while during drilling, it is in a more complicated state, under tension, pressure and twisting. During rotary drilling, the working condition and force of the drill column are especially complicated, and the drill column is like a long and thin rotating shaft. The whole drilling column is in the form of an approximate spiral curve with complex rotational movement.
Commonly used drilling tools
1. Kelly
The square drill pipe is located at the most... Its main function is to transmit the torsional distance and bear the total amount of the drill column. The driving part of the square drill pipe is divided into square and hexagonal, the most used in oil drilling is square, and the water eye is hexagonal, because the wall thickness is about three times larger than the drill pipe, and it is made of high strength alloy steel, so it has high tensile strength and torsional strength.
2、Drill pipe
Drill pipe is the basic component of the drill column, which is mainly used to transfer the torsional distance and convey the drilling fluid. The pipe body and the joint of the existing drill pipe are connected together by butt welding method. In order to increase the strength of the joint, the butt-welded part of the pipe body is thickened at both ends, and there are three types of thickening: internal thickening, external thickening and internal and external thickening.
3、Weighted drill pipe
Extra weight drill pipe is characterized by a wall thickness more than two times that of ordinary drill pipe, a longer joint than ordinary drill pipe, and a special wear-resistant roller in the middle of the pipe body. It is mainly used for the following applications:
1) It is used in the transition area of drill collar and drill pipe to ease the change of bending stress between them to reduce the damage of drill pipe;
2) To replace the drill collar in small boreholes for easy operation;
3) Replacing most of the drill collars in directional wells to reduce the occurrence of torsional distance and sticky stuck drilling, thus reducing costs and helping to maintain the orientation of directional wells. Because of the large contact area between the drill collar and the tight closure, a large friction force occurs with the well wall when it is rotated, thus making the borehole have a tendency to deflect, which can be reduced when the drill collar is replaced by the weighted drill pipe, thus helping to maintain the orientation of the directional well.
4、Drill collar
Drill collar is one of the main components of the drill column, its role is to provide drilling pressure to the drill bit, and at the same time make the lower drilling tool combination have greater rigidity, so that the drill bit can work steadily and help to overcome the problem of well slope. Drill collar classification:
1) Cylindrical type: made of common alloy steel, the drill collar is round inside and outside the cross section of the pipe body;
2) Spiral type: made of ordinary alloy steel, with spiral grooves on the outer surface of the pipe body;
3) Non-magnetic type: made of stainless alloy steel with low magnetic permeability, the drill collar is round in both inner and outer diameters of the tube cross-section.
5、Drilling tool stabilizer
1) Stabilizer is commonly known as a corrector, and a certain number of stabilizers are placed at a suitable position in the drill column to form the lower tool combination of the drill column.
It can prevent the well slope when drilling straight wells and control the borehole trajectory when drilling directional wells.
2) The use of stabilizers can play a role in improving the stability of the work of the drill bit, so that the life of the drill bit is extended, which is particularly important for diamond drill bits.
6、Non-magnetic drill collar
The structure of non-magnetic drill collar is the same as that of ordinary drill collar, but the chemical composition and mechanical properties are different from those of ordinary drill collar. Non-magnetic drill collar is a drilling tool with special function in directional well engineering. In order to make the compass not affected by the magnetic field of the drill column, a non-magnetic drill collar of a certain length must be equipped in the drill column, so that the magnetic inclinometer is located at a suitable position in the non-magnetic drill collar for inclination measurement, otherwise the correct measurement results cannot be obtained.
Leave Message
Consult Our Engineers & Get Fast Official Quotation
Give you the best solution
- Inquiries get a response within 12 hours.
- We are a professional manufacturer with competitive pricing, and we accept all DEM/ODM orders.
- Our after-sales team provides 24/7 technical support; issues are addressed within 24 hours.
- Precision quality, on-time delivery, tailored service.
We can customize high-performance drill pipe assemblies of various sizes according to customer needs.
Contact Us
Telephone
Phone/Wechat
Address
052260, East of Beikou, Yingli Town, Jinzhou County, Shijiazhuang City, Hebei Provice, China.
Get in Touch
* Fill in your phone number and email information, and we will promptly contact you within one business day to address your concerns as soon as possible.