Grooved drill pipe is one of geological exploration drill pipe. It needs thick-walled tubes for its body. At present, the grooves on the market mainly include single grooves, double grooves and three grooves. It is characterized by high bending strength and welding strength of grooved drill pipe, which can ensure the straightness requirement of deep hole drilling.
In order to solve the problem of screw fin cracking, easy stripping and no wear-resisting, in the welding of screw pipe, drill pipe in the soft coal seam with high pressure, leading to the difficulty of hole formation and even the waste of drill pipe, screw groove processing in the thick wall pipe by milling chips, improve the joint of drill pipe, the surface treatment of thread, and develop the whole screw pipe and body groove drill pipe.
The drive shaft is also one of the power systems of the grooved drill pipe, the equivalent of our body's joint system. Due to the structural limitations of the drive shaft assembly body, the outside diameter of the shaft should not be too large, thus affecting its stiffness and strength. In field use, it is a high-risk component of drilling tool accidents. Usually, it breaks from the upper end of the shaft body to the water cap where the thread retracted and from the transition point above the inner ring position of the lower TC bearing.
Analysis of fracture causes of grooved drill pipe shaft:
1. Due to the limitation of structural strength and alternating stress, the drive shaft is the weak link of drill tool strength. Under compound drilling conditions, its working conditions are poor. That's one thing.
2. The material selection of shaft body is unreasonable or the heat treatment process is inappropriate, and the mechanical strength is low. That's number two.
3. The fatigue crack of the transmission shaft is caused by long-term alternating load. This is number three.
4. Poor transition of shaft threads in tool drop pool or diameter change, forming stress gathering towel. These are the four main causes of fracture.
Grooving drill pipe needs to be maintained regularly, and rust and dust prevention should be implemented regularly. The drill pipe shall be selected according to the technical parameter type of the drilling distance within the rated drilling distance of the drill. In use, the special geological drilling pipe of mining should be impact welded with its matching joint. Therefore, the integral grooved drill pipe with high safety has good followability and high tensile strength, and can be adapted to traditional drilling and unloading. Understand the performance of the grooved drill pipe to better use it.
