Views: 0 Author: Site Editor Publish Time: 2024-12-12 Origin: Site
Bearing, as an important part of mechanical equipment, its performance can directly affect the machine's normal operation. However, any parts are not permanently unbreakable. When bearing problems occur, it not only affects the efficiency of the equipment but also may lead to greater mechanical failure.
What does a bad bearing look like? How do we judge it by performance and sound?
In this article, LNB Bearing Company will introduce the damage bearings characteristics, sound judgment methods, causes of damage, maintenance techniques and some FAQs (Frequently Asked Questions, etc., wishing it would be helpful for users.
The bearing is a mechanical part used to reduce friction between moving parts, which can help improve the operating efficiency and service lifespan of machinery equipment. Generally speaking, bearings are composed of 4 main parts: inner ring, outer ring, rolling element, and cage. Bearings are widely used in various large, medium, and small mechanical equipment, including electric motors, pulleys, medical equipment, industrial equipment, automobiles, marines, aeroplanes, and so on.
Bearings can be classified into countless types according to their material, size, structure, application, etc., and each type of bearing has its own usage. The following are a few common classifications of bearings.
Steel bearings:
Steel bearings are the most common bearing type, and are usually made of high carbon chrome steel, stainless steel, or bearing steel. Steel bearings have high strength, wear resistance and durability, etc. They are widely used in various industries.
Ceramic Bearings:
Ceramic bearings are mainly made of ceramic materials such as zirconia(ZrO2) or silicon nitride(Si3N4). Ceramic bearings have the advantages of light weight, low friction, corrosion resistance, high temperature resistance, electrical insulation, oil-free self-lubrication, etc., suitable for use in some special or extreme environments.
Plastic bearings:
Plastic bearings are mainly made of plastic materials (such as nylon, PTFE, or polyamide). Plastic bearings have the advantages of low noise and light weight and are used in household appliances and light machines.
Deep groove ball bearings: One of the most common bearings. They have simple structures and are suitable for carrying radial loads.
Angular contact ball bearings: Can carry radial and axial load at the same time, axial load capacity will increase with the contact angle increases.
Self-aligning ball bearings: Their inner and outer ring raceways are spherical and can be self-aligning. Self-aligning ball bearings are suitable for axial deviation caused by mounting errors and equipment with large load changes.
Thin section bearings: This type of bearing's width is small, the weight is light, and they are suitable for space constraints and lightweight needs of the design.
Thrust ball bearings: Specially designed for bearing axial load, usually divided into one-way and two-way two types.
Tapered roller bearings: The rolling elements are tapered rollers, they can withstand composite loads (radial and axial), usually installed in pairs.
Cylindrical roller bearings: The rolling elements are cylindrical rollers, suitable for carrying large radial loads, with a low coefficient of friction.
Needle roller bearings: This type of bearins' roller diameter is small, length is big, and suitable for carrying large radial load, but not suitable for the axial load.
Spherical roller bearings: With automatic self-aligning function, can withstand radial load and two-way axial load.
Thrust roller bearings: They are usually used to withstand axial load, with high load capacity.
Using special diagnostic tools can help us quickly determine whether the bearing is damaged. For example, the use of a mechanical stethoscope can help us pinpoint the source of noise and determine the abnormal sound of the bearing; the use of vibration analysis tools can detect irregularities in the operation of the bearing, etc.
(1) Ensure that the surrounding environment is quiet to avoid interference.
(2) Compare normal and abnormal sounds to identify differences.
(3) Regularly record the sound changes during bearing operation.
Performing a careful visual or tactile inspection to evaluate the bearing for corrosion, damage, or abrasion.
(1) Surface damage Abrasion, spalling, or pitting may occur on the raceways, rolling elements, or cage surfaces of the bearing. These damages may cause the bearing to run unevenly, which can reduce the performance of the equipment.
(2) Abnormal heat If the bearing temperature rises abnormally, it is likely to be caused by insufficient lubrication, overload operation, or damage to internal parts. This phenomenon requires timely inspection.
(3) Abnormal vibration Bad bearings often cause increased vibration of the equipment, especially in high-speed operation, where the vibration is more obvious.
(4) Reduced efficiency Damaged bearings may lead to increased resistance to the operation of the equipment, thereby reducing the efficiency of the work, and may even be jamming phenomenon.
A bearing in good rotational condition will make a low whining or buzzing sound. Sharp hissing, squeaking, and other irregular sounds often indicate that the bearing is in poor rotational condition. Sharp squeaking noise may be caused by improper lubrication, in addition to improper bearing clearance can also cause metal sound.
Loud metallic noise in bearings may be caused by overloaded bearings; poor mounting; insufficient or inappropriate lubricant contact of rotating parts, etc.
If the bearing occurs with regular noise, it may be due to foreign matter caused by rolling surface indentation, rust, or scar; bearing deformation, or rolling surface stripping, then you need to replace the bearing in time.
Bearing irregular noise, usually due to excessive clearance; foreign body intrusion; and spherical damage, stripping caused.
Bearing damage is caused by a variety of reasons, the following are some of the main factors:
Grease with impurities, insufficient lubricant (oil level is too low, improper preservation leads to oil or grease leakage through the seal) or poor lubricant oil quality will increase friction, resulting in premature bearing damage. Insufficient lubrication is one of the main reasons for bearing damage.
Bearing clearance is too large or too small. The bearing clearance is too small and too tight when rotating.
Wrong mounting may make the shaft bear uneven force and accelerate the wear. Eccentricity, excessive tapping, or incorrect use of tools during bearing mounting can cause irreversible damage to the bearings.
Dust, impurities, or moisture entering the inside of the bearing can destroy the lubrication effect and cause damage to the parts. Bearings mixed with sand or carbon particles and other impurities, play the role of abrasive; bearings mixed with water, acid or paint, and other dirt, play a corrosive role, and so on.
Bearings for a long time to withstand the load beyond the design range, will make its fatigue damage. Prolonged exposure to overloaded operation or exposure to excessive impact may lead to premature fatigue of the bearings.
High temperature operation will make the lubricant evaporate rapidly, resulting in lubrication failure. At the same time, high temperatures may degrade the performance of bearing materials, increasing the risk of damage.
Bad bearings may lead to the following consequences if they are not repaired or replaced in time:
Bearing damage will make the equipment can not run normally, directly affecting production efficiency.
Bearing problems may trigger damage to other parts, increasing maintenance costs.
In serious cases, bearing failure may lead to equipment failure, endangering the safety of operators.
(1) Maintain the original packaging, shall not be opened arbitrarily, if the packaging is found to be damaged, shall be opened and carefully cleaned, re-oiled packaging.
(2) The relative humidity of the storage room can not exceed 60%, and the temperature difference can not be too large.
(3) Sealed bearings or bearings with dust cover, after a long period of storage, the lubricating characteristics of the grease filled in the bearings may be reduced, and it is necessary to replenish the lubricant on time.
(4) It is strictly forbidden to put the bearings and corrosive things together to prevent corrosion and pollution.
(5) Large rolling bearings can only be flat when stored, the inner and outer rings of the side of the best all supported. If stored upright, due to the inner and outer ring and rolling parts of heavier, and the inner and outer ring wall being relatively thin, may cause permanent deformation.
Select appropriate lubricant or grease according to the working conditions of the bearings, and ensure that the lubricant is replenished on time to avoid dry friction.
During installation and maintenance, the working environment should be kept clean to avoid impurities entering the bearings. Regularly check and clean the bearings to remove internal impurities and old lubricants.
Check whether the fit clearance of the bearings meets the requirements before installation, avoid directly striking the bearings with hammers or other objects, and use special installation tools to ensure even force.
Ensure that the working environment temperature of the bearings is within a reasonable range, avoid high temperature environment.
Use professional tools for regular inspection to detect hidden dangers in advance. And record the data of each maintenance and inspection, so as to track the use of bearings for a long time.
(1) Select high quality bearings and lubricants, and inspect, maintain, and replace them regularly.
(2) Use professional tools to ensure proper installation.
(3) Avoid overloading or high temperature (exceeding the operating temperature range of bearings)
It depends on the degree of damage. If it is only slightly worn, it can be repaired by re-lubricating or adjusting the mounting; however, if it is severely damaged, it is usually necessary to replace the bearing with a new one.
The service life of a bearing depends on its material, usage environment, and maintenance. Generally speaking, high-quality bearings can last for thousands of hours, but without regular maintenance, the life may be greatly shortened.
(1) Mechanical stethoscope: for checking abnormal sound.
(2) Infrared thermometer: To detect temperature changes in bearings.
(3) Vibration analyzer: to monitor the vibration condition of the equipment.
You can tell if the lubrication is adequate by checking the colour, viscosity, and smell of the lubricant, as well as the operating temperature and sound of the bearing.
