Research On Impact Resistance Testing Device Of PDC For Drilling

Polycrystalline diamond compact(PDC) bits have been a significant contributor to the greatly improved efficiencies and economics of oil and gas drilling and exploration drilling over the last thirty years.The contact pressure is proportional to the depth of indentation when PDC is cutting rock. The drilling pressure should be controlled reasonably when the PDC bit is used. In the form of failure, the failure modes of a single PDC tooth mainly include fracture, falling off and broken tooth. The maximum size of the force is on the side of the tooth, which is the most likely to break or break. Therefore, the use of PDC drill bit shouid be payed the attention of the regular inspection of the side teeth.Test method of polycrystalline diamond composite sheet includes the friction test,impact test, etc. The friction life of the material under the action of abrasive material is mainly determined by the strength and hardness of the material. So all of the friction tests are hard rock minerals, such as quartz, corundum or diamond. At present, at home and abroad commonly used PDC impact test methods for the properties of main method of high speed particle erosion, PDC cutting with granite trough, rotating rod impacting method, weight impact method and transform impact work drop ball impact method. Test method for improvement of PDC shock resistance test method, the main key is the performance testing equipment is improved, the PDC shock resistance performance test in the operation, the record is more simple, and the most important force simulated situation can be more paste within the actual hole stress. Anti shock performance reflects the PDC toughness and bonding strength, is a comprehensive index, is to determine the use effect is good or bad, the key. Therefore, the PDC shock resistance test method and test device were improved has very important practical significance.In this paper, the design of a kind of electromagnetic adsorption impact tester is designed to evaluate the impact resistance of PDC. Electromagnetic adsorption type impacttester working principle is to use a high power electromagnetic coil electricity hammer suck,power off and then, hammer by falling weight impact energy, the diamond composite ball tooth under a certain number of times of shock after be destroyed. At the moment, the instrument control part that can show the impact frequency, impact number multiplied by the weight of single impact energy can be indicators of impact resistance of composite button,the unit is time – Joule. Because the hammer weight is fixed, the stroke and the single impact work can be adjusted by adjusting the positioning screw and the beam height. The impact test instrument is used to measure the impact resistance of diamond composite balls(or diamond composite pieces, which need to be replaced).Adsorption type electromagnetic hammer impact tester will absorb a certain height,then free fall and have a certain impact. Count the number of times the impact of the record.The height of the falling height of the hammer is 150 mm, and the weight of the hammer is6 kg. By contrast experiment, the thickness of PDC increases, and the impact resistance performance is enhanced. The thickness of PDC layer increases, and the impact energy is absorbed. The finer the particle size of diamond powder, the better the impact resistance of diamond powder. The finer the particle size, the smaller the spacing between the grains, the better the impact resistance, the more coarse diamond powder, the worse the impact resistance.