HDD drill pipe is selected by the drill pipe material, cross-section shape, geometric size, and specification length. It is selected according to the size of the impact work of the rock drill, the degree of softness and hardness of the rock, the diameter of the drill head, the depth of the rock hole, the connection requirements of the rock drill used to the drill tail shank, and the rock drill’s feed method.
Usually under the premise of meeting the drilling requirements, drill pipes with moderate cross-section, light weight, short length, good rigidity and long life should be selected as much as possible.For hand-held rock drilling, H22 and H25 drill rods with taper connections and hexagonal cross-sections are generally selected. The size of the drill tail is 108mm x H22 and the material is 55SiMnMo, 95CrMo, etc. For flat-lane excavation and rock drilling, H25, H28, H32, and H35 hexagonal cross-section threaded connections with the same diameter, reducing diameter and quick-change drill rods are generally selected.For the production of rock drilling (underground and open-pit mining), D35, D38, D45, D51, D60, D65, D76, and D87 circular cross-sections, threaded connections of the same diameter, reducing diameter, and quick-change drill rods and drill pipes are generally selected.
The selection principle of the specification length is: it is determined according to the drilling depth requirements, generally in 0.3—7.3 Within mm range.
Post time: Dec-19-2022