The Use of New Wear-Resistant Materials in the Development of Two-Level Bits with a Balanced Resultant Moment at the Drilling Flight

Abstract

Two-level bit with a planetary reducer is described in the article. The thrust ball bearings of the planetary reducer are supposed to be replaced by bearings with inserts from grounded -in PDC plates. The scheme of this bearing is given, the research on its bearing capacity is carried out. The results of PDC cutters’ tests for wear depending on depth and penetration in rock are also given. The test results for PDC wear resistance are given in conditions of drilling a well with standard cutters and the cutters that have undergone cryogenic-magnetic treatment. The results of tests on wear resistance of standard PDC plates, PDC plates with leached subsurface layer, and leached PDC plates, covered with additional diamond coating are given. Therefore the existing technologies allow to increase the PDC wear resistance in two-level bit by 1.7-2 times compared to the standard PDC plates. The reasons of the PDC plates chipping are considered, the link between the torque at the drill string and the probability of the PDC plates’ chip is discussed