Drill pipe is a very important tool in drilling operations, mainly used to transmit rotational power and withstand the pressure generated during drilling. They can be divided into multiple types and different specifications according to different application scenarios, technical requirements and structural characteristics.
Single-layer joint drill pipe
Single-layer joint drill pipe is a common type of drill pipe, and seamless steel pipe is often used as the material. It is characterized by a single drill pipe and a joint. The joint is used to connect two drill pipes to ensure that the overall length is suitable for different drilling depths. It is generally suitable for simpler drilling tasks, and is easy to maintain and low in cost.
Its specifications are shown in the following table:
Drill pipe model |
Outer diameter (inch) |
Length (feet) |
NWJ |
2 3/8 |
10 |
HWJ |
3 1/2 |
10 |
PWJ |
4 1/2 |
15 |
Double-layer joint drill pipe
Double-layer joint drill pipe is more widely used. It is composed of two drill pipes and multiple joints. Compared with single-joint drill pipe, double-layer joint drill pipe is more outstanding in strength and durability. It is suitable for deep drilling and withstands higher pressure and load.
Its specifications are shown in the following table:
Drill pipe model |
Outer diameter (inch) |
Length (feet) |
NZ |
2 3/8 |
6-10 |
HZ |
3 1/2 |
6-10 |
PZ |
4 1/2 |
10-15 |
Box drill pipe
Box drill pipe is a special type of drill pipe. Its design allows the drill pipe to remain stable under high load. Box drill pipe is usually used for deep well drilling or special drilling environment, and has stronger pressure resistance and wear resistance.
Its specifications are shown in the following table:
Drill pipe model |
Box length (inch) |
Segment length (foot) |
HH |
18 |
10 |
PH |
18 |
15 |
CH |
18 |
20 |
Internal impact drill pipe
Internal impact drill pipe is a type of internally driven drill pipe. The structural design allows the impact force to be effectively transmitted between the drill bit and the drill pipe. When drilling hard rock or encountering obstacles, this drill pipe effectively breaks the rock formation through the reaction force generated by the internal impact head.
Its specifications are shown in the following table:
Drill pipe model |
Outer diameter (inch) |
Impact head length (inch) |
DHD 340A |
4 1/2 |
12 |
DHD 350R |
5 1/2 |
14 |
DHD 360 |
6 1/2 |
16 |
External impact drill pipe
External impact drill pipe is also a commonly used type of drill pipe. Similar to internal impact drill pipe, it is also used for difficult drilling operations, but its impact force transmission is completed through an external device. This type of drill pipe is usually used for drilling tasks in hard rocks or obstacles that need to be broken.
Its specifications are shown in the following table:
Drill pipe model |
Outer diameter (inch) |
Impact head length (inch) |
SD 4 |
2 5/8 |
10 |
SD 5 |
3 1/8 |
12 |
SD 6 |
3 1/2 |
14 |
Double round drill pipe
Double round drill pipe is a type of drill pipe used for mud circulation. It usually needs to be assisted by special pup joints and casing pipes. Its uniqueness lies in the different inner and outer diameters of the drill pipe, which can effectively optimize the circulation process of mud, help reduce friction during drilling and increase drilling speed.
Its specifications are shown in the following table:
Drill pipe model |
Inner diameter (inch) |
Outer diameter (inch) |
NC 23 |
2 1/4 |
3 |
NC 26 |
2 3/8 |
3 1/2 |
NC 31 |
2 7/8 |
4 |
Summary
Drill pipes of different types and specifications have their own unique application scenarios in different projects. The above is an introduction to the specifications and models of various drill pipes. If you need more detailed information, please refer to the relevant product written materials or consult relevant professionals. By properly selecting the drill pipe model, drilling efficiency can be improved and operational risks can be reduced.