Research On Reliability And Life Test Technology Of Rolling Linear Guideway

With the background of the National Science and Technology major projects "the generic technology of rolling functional unit for high-grade CNC machine tools", this paper is based on the reliability test bench and the life test bench for linear guides, and aimed to do theoretical and experimental research on reliability features of linear guides.Domestic linear guide products are relatively backward in terms of reliability. This paper did some research on analysis and evaluation methods of rail reliability. Through statistical analysis of the actual production in the workshop, this paper got the correspondence of MTBF between linear guides and the CNC machine tools. On this basis, designed the reliability and life test methods. Proposed a reliability evaluation method for non-fault conditions. And based on the Weibull distribution model, proposed the data analysis methods for small sample data reliability test.This paper did some preparation before the test, including redesigning of the loading mechanism, and designed the load control systems, data collection and monitoring system of the test bench, and also designed the specific programs of the test, including the calculation of the load and speed, and the implementation and recording of the test.This paper carried out the reliability qualification test of four manufacturers of rail products, and compared the reliability difference between domestic and foreign products; Select one of them and carried out the accelerated life test, and got the failure data and failure sample of this linear guide, virtual augmented this failure sample and obtained multiple sets of failure data, draw the probability of drawing of the two-parameter Weibull distribution, calculate the size and shape parameters of the distribution function, and then obtained the Weibull distribution function and the probability density function of this type of rail products.Based on the test results, this paper analyzed the fault and failure modes of linear guides, and proposed measures to improve rail reliability; analyzed the shortcomings of the existing life and rated dynamic load calculation formula, and proposed the formula parameter correction method.