Development On Test Device For Detecting The Performance Parameters Of Screw Drill Tools Of Simulating High Temperature Field

At present,the directional drilling technology is more and more widely used with the implementation of deep drilling plan.There are more and more directional boreholes,horizontal boreholes,and inclined boreholes with certain vertical angles.At the same time,the depth of drilling is also increasing.The increase of drilling depth will result in the increase of the temperature at the bottom of the boreholes.At the bottom of deep boreholes,the temperature is as high as 170,or even higher due to the average temperature gradient(generally 3 /100 m)when drilling to that bottom of the "3000-5000 m" deep boreholes.The temperature at the bottom of the deep boreholes will be higher in the areas with the abnormal geothermal gradient,and this situation is very common in some place.As a kind of power tool at the bottom of deep boreholes,the screw drilling tools directly bear the influence of the high temperature environment of the deep boreholes.However,the high temperature environment will greatly affect the rubber bushing that makes up its stator part due to the special structure of the screw drilling tools,causing it to expand seriously.On the other hand,metal screw drills can also make small changes in high temperatures.These changes will lead to a significant change in the performance of the screw drill,which will result in a sharp reduction in the output power and a rapid shortening of service life,and even direct damage.In this paper,it is necessary to acquire the performance parameters of the screw drilling tools under the high temperature condition through a test device,in order to improve the working performance and prolong the service life of the screw drill tools.This paper studies this issue:The first chapter describes the background and significance of the research,and makes literature research on the research status of the test device at home and abroad.It puts forward the contents and methods of the research;The second chapter analyzes the relationship between the performance parameters of the screw drilling tools,and determines the test parameters and theirs range of the test device.It designs the overall structure of the test device;In the third chapter,the corresponding sensors are selected according to the technical parameters of the test device.It introduces the working principle and functions of various sensors;In the chapter 4,the high temperature system is designed from the simulation of high temperature field,the selection of heat conduction medium,the way of heat conduction,the control of temperature circuit and automatic adjustment,the selection of thermal insulation materials,the determination of insulation thickness,and so on.What's more,the finite element analysis of the temperature distribution of the high temperature system is carried out by the temperature field simulation function of ANSYS Workbench.The feasibility and reliability of the system are verified by software simulation;The fifth chapter is the laboratory test.It tests the reliability and stability of the device and its high temperature system.The results show that the high temperature system achieves the temperature value of 200? successfully,and can simulate the stable temperature field under the different temperature value of 200?.The reliability of high temperature system is verified.The various functional systems of the test device are also tested by adjusting different gear positions of the mud pump,including the outlet pressure,the output speed,the output torque and the output power at the different flow rate.The test result shows that all the major systems of the test bed work normally.It verifies the stability of the test device.In this paper,the test device adopts the positive test principle for design and development,and it has been modified in terms of temperature.The high temperature field simulation function module was designed on the basis of the traditional test device.At present,most of the test devices are designed and developed by the principle of reverse testing,and can only realize the performance test of screw drilling tools in normal temperature.Moreover,these test devices have simple structure and limited function.Compared with these test devices,the test device in this paper is closely related to the high temperature of deep boreholes.It can provide the high temperature environmental conditions for the performance test of the screw drill by simulating the actual conditions on the surface when the screw drill is located in the high temperature environment of deep boreholes.The test device meets the requirements of simulating the high temperature environment when the screw drilling tools is working in deep boreholes,and the measured performance parameters by the test device are real and accurate,which can directly reflect the working performance of the screw drilling tools.