Wear failure refers to failure caused by normal wear and tear that has been anticipated during design and is unavoidable. Wear failure is a failure caused by normal wear and tear. For this type of failure, it is generally necessary to predict the life, replace parts or components, and compensate for the gap caused by wear.
For example, if a CNC machine tool works normally, but the position deviation in the Z (X) axis direction is too large, the fault may be that the gap is too large due to wear of the screw, which requires mechanical gap adjustment or replacement of the screw. lever, or you can select parameter settings in the working mode selection and enter the backlash compensation of the Z (X) axis to determine whether it is a wear failure.
According to the nature of equipment failure, equipment failure is divided into three types: congenital, wear and abuse. Among them, wear failure is the most common and regular type of failure, and elaborating the principles and countermeasures of wear failure is an important part of the basic theory of modern equipment management.
The wear and tear of mechanical equipment can be divided into two aspects: visible wear and invisible wear.
Tangible wear and tear, including changes in the physical form of the equipment due to friction, impact, vibration, fatigue, corrosion, deformation, etc. during use, resulting in gradual (or sudden) loss of functionality; also Including changes in the physical form caused by corrosion, deterioration, aging and other reasons during the idle process of the equipment, which reduce or even lose the function.
Invisible wear and tear is manifested in the depreciation of the value of equipment, which is not caused by the influence of natural forces during use. There are two reasons for depreciation:
The first is due to technological progress and the improvement of labor productivity, the consumption cost of producing the same equipment continues to decrease, forcing the original equipment to depreciate, also known as the first type. Invisible wear and tear.
The second is due to the emergence of new equipment that is superior to the original equipment in terms of structure, principle, function, cost, etc. The original equipment appears to be technically obsolete and functionally backward, and the resulting depreciation is also It’s called the second kind of invisible wear.
The countermeasure for equipment wear and tear is compensation. Compensation for equipment wear and tear is a technical organizational measure for additional investment in order to restore or improve the function of the components of the equipment system. The mode and degree of wear are different, and the corresponding compensation methods are also different.
There are three ways to compensate for equipment wear and tear, namely repair, replacement and technical transformation. Some physical wear and tear can be repaired through repair techniques. For some losses, such as parts breakage, material aging, etc., the original functions can only be restored by replacing parts or equipment. The elimination of invisible wear can only be achieved after taking measures to improve its technical performance and improve its technological advancement. During the maintenance work of the generator set, there may be repair, replacement and technical transformation work at the same time. There are significant differences between these three different types of work. As a compensation method, it is a countermeasure for equipment management. Which compensation method is adopted depends on the wear form and degree of wear of the equipment, but in the final analysis it depends on the economic evaluation of the compensation. . The function of compensation restores and improves the reliability, maintainability, and availability of equipment.
Therefore, the purpose of equipment maintenance is to re-improve the equipment system and restore or improve the function of the equipment. While the loss of equipment is compensated in physical form, its economic value is also compensated. The core issue of equipment maintenance is to select the correct maintenance method and maintenance level for specific equipment based on the wear and tear of the equipment and the business objectives of the enterprise, and reasonably arrange the maintenance plan and implement it.