Method for assessing reliability of main shaft of kilometer deep shaft hoist by considering multiple failure modes

Abstract

The invention discloses a method for assessing the reliability of a main shaft of a kilometer deep shaft hoist by considering multiple failure modes. The method comprises the steps of firstly, building a parametric three-dimensional model of the main shaft according to the structure size of the main shaft; secondly, according to a probability attribute of a random variable of the main shaft, establishing a sampling matrix of the random variable, and solving strength and stiffness response of the main shaft under the sampling matrix by using a finite element method; thirdly, establishing an explicit function between the response and the random variable matrix by using a neutral network method, and according to strength and stiffness design criteria, establishing explicit functions in strength and stiffness failure modes; fourthly, calculating two failure probabilities by using a saddle point approximation method; and finally, building a joint failure probability model between the two failure modes through a Clayton copula function, and solving system reliability under joint failure by using an interval reliability method. According to the method, the probability correlation between strength failure and stiffness failure is considered, so that the system reliability of the main shaft of the hoist can be assessed more accurately and reasonably.

Description

technical field [0001] The invention relates to a system reliability evaluation method of a mechanical product for the main shaft of a hoist in a kilometer deep well and considering the probability correlation of failure modes, and belongs to the technical research field of mechanical structure reliability. Background technique [0002] At present, most of the coal wells in my country are shallow wells, 500-800m deep to the ground, and coal resources buried at a depth of 1000-2000m account for about 53% of the total reserves, and a kilometer-deep well hoisting system must be used (including hoists, hoisting containers, lifting wire rope, etc.). As the main load-bearing part of the hoist, the main shaft bears all the torque of lifting and lowering the load, and also bears the tension of the steel wire ropes on both sides. As the depth of the well reaches more than 1,000 meters, the maximum static tension of the hoist and the number of winding layers of the main shaft drum inc...

AI Technical Summary

Problems solved by technology

Due to the homology of the excitation and the identity of the characteristic parameters of the characterization system, there is a common correlation between the faults of the main shaft of the hoist. Neglecting this feature will make it difficult to obtain accurate failure data and reliability information.

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