The principle and countermeasures of wear and tear faults in mechanical equipment

Wear and tear failure refers to the failure caused by normal wear and tear that was anticipated and unavoidable during the design process. Wear and tear failure refers to the failure caused by normal wear and tear that was anticipated and unavoidable during the design process. Wear and tear faults are faults caused by normal wear and tear. For these types of faults, it is generally necessary to predict their lifespan, replace parts or components, and compensate for gaps caused by wear and tear. For example, if a CNC machine tool is working normally, but the position deviation of the Z (X) axis direction is too large, the fault form may be due to excessive clearance caused by the wear of the lead screw, which requires mechanical clearance adjustment or replacement of the lead screw. Alternatively, in the work mode selection, parameter settings can be selected and the reverse clearance compensation of the Z (X) axis can be input to determine whether it is a wear fault.

The principle and countermeasures of wear and tear faults:

According to the nature of equipment failures, they can be classified into three types: congenital, wear and tear, and overuse. Among them, wear and tear faults are the most common and regular types of faults, and explaining the principles and countermeasures of wear and tear faults is an important content of the basic theory of modern equipment management.

The wear and tear of mechanical equipment can be divided into two aspects: tangible wear and intangible wear.

Tangible wear and tear, including changes in the physical form of equipment caused by friction, impact, vibration, fatigue, corrosion, deformation, etc. during use, resulting in a gradual (or sudden) decrease in its function and loss; This also includes changes in physical form caused by factors such as rust, deterioration, and aging during the idle process of equipment, resulting in reduced functionality and loss of functionality.

Intangible wear and tear is manifested in the depreciation of equipment value, which is not caused by the influence of natural forces during use. There are two reasons for depreciation:

The first type is due to technological progress and the improvement of labor productivity, which continuously reduces the consumption cost of producing the same equipment, forcing the original equipment to depreciate, also known as the first type of intangible wear and tear.

The second type is due to the emergence of new equipment that is superior in structure, principle, function, cost, and other aspects compared to the original equipment. The original equipment appears technically outdated and functionally outdated, resulting in depreciation, also known as the second type of intangible wear and tear.

The countermeasure for equipment wear is compensation. Compensation for equipment wear and tear is a technical and organizational measure taken to restore or improve the functionality of the components of the equipment system. The way and degree of wear vary, and the corresponding compensation methods also vary.

There are three compensation methods for equipment wear, namely repair, replacement, and technical transformation. For some tangible wear and tear, repair techniques can be used to repair them. For some losses such as component breakage, material aging, etc., their original functions can only be restored through component or equipment replacement. The elimination of invisible wear and tear can only be achieved after taking measures to improve its technical performance and improve its progressiveness of technology. In the maintenance work of generator sets, there may be simultaneous repair, replacement, and technical renovation work. These three different types of work have significant differences (see Figure 1). As a compensation method, it is a countermeasure for equipment management. The choice of compensation method depends on the form and degree of equipment wear, but ultimately depends on the economic evaluation during compensation. The role of compensation is to restore and improve the reliability, maintainability, and availability of the equipment.

So, the purpose of equipment maintenance is to improve the equipment system and restore or enhance its functionality. While compensating for the loss of equipment in material form, it also compensates for its economic value.