What kinds of drill pipe joints are there?

What kinds of drill pipe joints are there?

The drill pipe joint is an integral part of the drill pipe, which is divided into a male joint and a female joint, and is connected to both ends of the drill pipe body. In order to enhance the connection strength of the joint, the wall thickness of the pipe body needs to be increased at the joint part. According to the thickening method, it can be divided into three forms: internal thickening, external thickening, and internal and external thickening. There are threads (coarse buckles) on the joints, which are used to connect each single drill pipe. The drill pipe joint thread is a tapered pipe thread with a sealing shoulder. The shoulder surface is tightened for sealing, and the thread is only for connection. The thickening method is different, and the screw type of the corresponding joint is also different.

Button type of drill pipe joint

1. Inner flat type: mainly used for external thickening of drill pipe. Its characteristic is that the drill pipe has the same inner diameter, and the drilling fluid flow resistance is small; but the outer diameter is large, which is easy to wear.

2. Through-hole type: mainly used to thicken drill pipe inside and outside. It is characterized in that the drill pipe has two inner diameters, and the flow resistance of drilling fluid is larger than that of the inner flat type, but its outer diameter is smaller than that of the regular type.

3. Formal type: Mainly used for inner thickening of drill pipes, drill bits, and salvage tools. Its characteristics are that the inner diameter of the joint inner diameter is smaller than the inner diameter of the pipe, the drilling fluid flow resistance is large, and the relative flow resistance is large among the three button types, but the outer diameter is small and the strength is large. The above three types of joints all use V-type threads, but the buckle type, distance, taper and size are very different.

4. Digital type: This is a thread expressed in numerical values of inches and tenths of an inch of the pitch diameter of the thread base. It is used in drilling tools such as kelly, drill pipe, drill collar, drilling tool stabilizer, etc.