Ways to Improve the Drilling Effectiveness of Rock Bits by a Tribological Method

Wear tests on the main bearings of 8.5 inch XHP 3 rock bits were performed, from which it is concluded that the way to improve the drilling effectiveness for the rock bits is to set drilling pressure and rotary speed properly, and to develop a new type of grease for rock bits which can bear a higher temperature than conventional grease. In addition, it is also shown that an inexpensive copper alloy can take the place of expensive Ag85Mn15 as an anti-wear material in the bearing, so that the production cost for the rock bits can be reduced.