Structure Design And Optimization Of Axial Impact Motor Vibrator

As the international oil prices falling down and the costs of exploration and development rising up,the oil-gas exploration and development is facing lots of serious challenges at home and abroad.Deep formation needs more exploration and development,in the drilling construction there are more complex,hard and high level of rock drilling ability formations,thus it increases the difficulty of the drilling construction,the drilling efficiency is pretty low.How to improve the drilling efficiency is particularly important,the downhole accelerated tools has a pivotal position for drilling speeding.Therefore,to design an effective speeding tools with long service life has important significance for drilling industry.Based on researching and analyzing the structure,working principle,advantages and disadvantages of speeding tools at home and abroad,in the meanwhile combining the characteristics of drilling technology,the movements of drilling fluid in the pipeline and the drilling way of bit for drilling which is rotated by screw drilling tools,a kind of tool is designed which can both rotate the drilling bits and produce continuous,axial and flexible impact(also known as axial impact motor vibrator).The axial flexible impact tool includes screw drive part,vibration impact sub and disc valve(the dynamic plate valve and the fixing valve).The working principle of this tool is: when drilling fluid flows through the rotating drive part(the downhole drill motors),it can transfer kinetic energy into mechanical energy of part of the liquid,then rotates the dynamic disc valve of hydraulic pulse device while rotating the drill bit,then makes cyclical change of the flow area between the dynamic plate valve and the fixing valve,then the hydraulic pulse device continues to make the drilling fluid produce pressure pulse,the oscillation sub part of the tool transfers pressure pulse into shock vibration,and then passes it to the drilling bit,finally makes the drilling bit produce rotating impact rock fragmentation effect and achieve the purpose of speeding.In order to verify the feasibility of the axial impact motor vibrator and optimize the structure of the tools,the transient flow theory is introduced into this tool and the hydraulic pressure pulse wave model is established in this paper,then the matlab is used to program for the hydraulic pulse numerical simulation,and the influence of different factors on the impact vibration performance is analyzed.On this basis,the prototype tool was processed and a laboratory test was carried out.The test verified the rationality of the design of axial impact motor vibrator,the validity of the theoretical analysis and the accuracy of the numerical calculation.The design of the tool and theoretical analysis provided theoretical support on drilling site and offered some guidance significance for optimizing the pulse tools which can improve drilling rate.