Design And Development Of New High-torque Washover Pipe

To some degree,the emergence of mechanical-electric compound drive drill rig solve the faults of pure mechanical drilling machine which with the drive system structure is complex, low transmission efficiencyd and installation inconvenience. Along with the energy-saving generator to join in the compound transmission box, bring such drilling rig has good economy and practicality advantages.However,in actual use process,the mud displacement of the different well depth cannot meet the requirements of drilling technology when the diesel engine speed adjusting range is narrow. Frequent replacement of cylinder liner can reduce drilling efficiency and increase the workers labor intensity also. Diesel engine speed range is too big, can lead to energy saving power frequency of the generator does not meet the requirements of electrical equipment, affect the performance of the electrical equipment. Therefore, how to solve the problem of the adjustment of the mud pump displacement and the allows input speed of saving energy generatorsk, becomes the key to limit such rig promotion and develo pment. To cure the above problems, in this paper a new type of compound transmission system has been developed for 7000 m mechanical-electric compound drive drill rigThe main research content is as follows:1) In the paper the new transmission scheme and structure of power transmission shaft be designed. Through the rolling off the clutch and shift fork,the pumping speed of mud pump can be multi-position adjusted. In this way, the mud pump can output mud continuously with different displacement,in as much as possible don’t change the cylinder size and ensure the generatior working under the premise of normal work.2) Various operating mode are analyzed when compound transmission system driving the draw works and mud pump.The fatigue strength and bending fatigue strength of the transmission shaft are checked and calculated. The service life of components and the bearing capacity of interference fit on the shaft is calculated too.3) According to internal structure characteristics, lubrication and cooling system requirements and lifting transportation factors, the box of drive system is designed. Through ANSYS Workbench software, optimized and calculated the structure of the box.Under the premise of meet the requirement of function stiffness and strength.The system could have the advantage of lightweight, compact structure, easy to transport.4) Design lubrication and cooling system for this type of compound transmission system. According to the actual operating mode, the size of lubricating system and the power of pump is determined by analyzing data of the heat load of Lubrication and cooling system; Considering the external environment temperature, the power of cooling fan is determined.