Development of a laboratory tribotechnical facility for testing PDC cutters for wear

In the practice of drilling oil and gas wells with diamond bits equipped with PDC cutters, cutter quality non-compliance with the declared class occurs. At the same time, the currently used methods of full-scale testing, when granite stone is used as a counterbody, are time-consuming and expensive, which complicates their use for prompt incoming inspection of new batches of PDC cutters arriving for assembly of diamond bits. This necessitated the development of a laboratory tribotechnical facility for quantitative assessment of the ability of PDC cutters to resist abrasion against abrasive materials. The study covers the development of a specialized tribotechnical facility that allows testing PDC cutters of various sizes for wear during friction against a diamond-containing metal work face, for which it is proposed to use diamond cutting wheels. The developed laboratory tribotechnical facility includes: an electromechanical rotary drive (a drilling-and-milling machine); a measuring unit with sensors for normal loads, friction force and temperature of cutter self-heating during testing; a lever loading mechanism; a set of mandrels for the possibility of installing PDC cutters of various sizes; a data collection system and licensed software. The results of practical evaluation of the developed laboratory tribotechnical facility on PDC cutters of various batches showed that testing on the new equipment allows for quick collection of data on the wear rate of the working edges of PDC cutters. The developed methods, equipment and criteria can be used to certify the wear resistance of PDC cutters.