Design of the Wire-Line Coring Drill Rod and Static Analysis on Its Joint

The wire-line coring drill rod is easy to vibrate under the influence of gravity in tunnel horizontal hole construction because of its thin wall, the friction between rod and hole wall causes the damage to the rod. The newly developed high strength wire line drill rod adopts the structure which welds the rod and the male and female joints and thickens the male and female joints to improve the strength. Aiming at the present situation that the joint threads of rod are easy to be damaged, an axisymmetric analysis model of the joint is established, After meshing, constraint, load addition and data analysis, the stress distribution of the rod under the pull torsion load and compression torsion load is obtained, and the results shows that the strength of the male and female joints of the rod meets the strength demand. This rod is equipped with ZDY1000G full hydraulic drilling rig, BW-250 mud pump and wire-line coring drilling tool, and their industrial tests with no break of rod or excessive wear of joint were carried out in Baoji Gold Mine and Luming Gold Mine, the cumulative footage of the tests reached 1442.9 m, which verifies the reliability of the rod effectively.