Research On Precision Retention And Acceleration Test Methods For Ball Screw Pairs

With the background of the National Science and Technology major projects" Common technology research and capacity building of functional unit test(2016ZX04004007)",this paper is based on the precision retention test bench of ball screw,and aimed to do theoreticaland experimental research on precision retention of ball screw,accelerated test method is researched to increase efficiency.In view of domestic research on ball screw is relatively backward in terms of precision retention and experiment,the failure of precision retention is analyzed based on the theory of reliability research.Different stresses’effect is researched according to the mathematical model of precision retention,and the test stress and boundary conditions are determined.The evaluation method of precision retention and the method of accelerated test are rasearched.Environment stress screening test scheme is designed,including screening method,stresses,stresses condition and screening process.Screening test of ball screw is done and early faults are found out based on the performance test bench of ball screw.Process of precision retention test,method of on-line measurement of precision and preload are designed on the precision retention test bench.Constant stress accelerated method is used to accelerate the precision retention test,the distribution parameters and different confidence levels of MTBF are analyzed by researching the evaluation method of Weibull distribution according the test data.The A+A accelerated test scheme and data evaluation method based on step stress accelerated test method is designed,which is suitable for the rapid determination and analysis of the precision of the ball screw products in the factory.Acceptance test method of precision retention is analyzed,suitable sampling scheme and statistical test program are selected,specific statistical cases is analyzed,reasonable acceptance plan according acceptance risk of the producer and the recipient is chosen,and MTBF of precision retention by the decision of receive or reject is estimated.