How to select geological drill pipe
1、 Understand drill pipe properties.
Geological drill pipe is a kind of drilling tool which uses alloy steel pipe to thicken by upsetting at both ends, turning small pitch taper thread, and connecting with lock joint. It is used in the field of geological exploration to transfer drilling torque to bottom hole bit, and is responsible for transferring drilling fluid. Common specifications are Φ 34*1m、 Φ 42*1m、 Φ 50*1m、 Φ 60*1m、 Φ 63.5*1m、 Φ 73 * 1m, etc. the common connection methods are male female connection (taper thread) and joint connection (rectangular internal thread).
2、 Understand the material of drill pipe.
At present, the national standard materials are dz40, dz50, DZ60, r780 and so on. Among these materials, r780 is the best, which has outstanding performance in toughness and wear resistance. The geological drill pipe body produced by Yikuang technology adopts special alloy steel pipe (r780, dz50) for geology, and the geological drill pipe bit adopts high-quality alloy structural steel (42CrMo). After rough machining, it is subjected to vacuum quenching and tempering heat treatment, and after finishing, it is subjected to surface nitriding treatment, which can effectively eliminate the problems of gluing and pulling, and is more wear-resistant and easy to disassemble, The fatigue strength and shear strength are greatly improved.
3、 According to the drilling capacity parameters, drilling diameter and drillable depth of the drilling rig, the drill pipe diameter is determined according to the empirical ratio of D / D = 4.5.
4、 According to the main parameters of drill pipe design, namely torque and feed pressure, the drill pipe is selected.
We know that the transmission torque of drill pipe is by the meshing and extrusion of key and key groove. Due to the processing accuracy, material properties, welding process and other reasons, it is impossible to evenly divide the torque on each key, and each contact key can not contact the force evenly, so the long key often occurs local torsional damage, When selecting the design torque of drill pipe, it must be greater than the design torque of drilling machine.
5、 Understand the process of drill pipe.
Good geological drill pipe in addition to the selection of high-quality materials, surface hardening is also very important to ensure wear resistance. The standard processing of the thread part can ensure that the joint can be unscrewed frequently without being damaged. The geological drill pipe produced by Yikuang technology adopts the advanced friction welding process. The drill pipe has the characteristics of high bending strength and firm welding, which can meet the requirements of straightness in deep hole drilling and has a long service life.