Sliding bearings (especially bronze bushings) are commonly used components in mechanical equipment and are widely used in industrial machines, vehicles, ships and other equipment. As a component that bears large loads and high pressures, the failure of sliding bearings will affect the normal operation of the equipment and may even cause serious damage to the equipment. The following are several common failures of sliding bearings (bronze bushings) and their causes:
1. Wear failure
Failure description: Wear is one of the most common failures of sliding bearings, which is usually manifested as loss or depression of the bushing surface material, especially under long-term load, caused by friction between the bearing surface and the shaft or other mating parts.
Cause:
Insufficient lubrication: Lack of sufficient lubricating oil or poor lubricating oil quality leads to increased friction.
Material mismatch: Improper material matching between the shaft and the bushing leads to excessively high friction coefficient and severe wear.
Uneven load: Uneven load distribution may also cause severe local wear.
Consequences: If the wear is severe, the bearing clearance increases and the lubrication effect is poor, which in turn affects the normal operation of the equipment and may cause equipment overheating, increased noise and even component damage.
2. Corrosion failure
Failure description: Corrosion is usually caused by the presence of harmful gases or liquids in the environment, or contamination of the lubricating oil. Bronze material itself has certain corrosion resistance, but it may still corrode in seawater or strong acid environment.
Cause:
Environmental factors: If the equipment is operated in a humid and highly corrosive environment (such as seawater, acidic gas, etc.), the bronze bushing is susceptible to chemical corrosion.
Lubricant contamination: Contaminants, acidic substances or water enter the lubrication system, reduce the quality of the lubricant, and cause corrosion on the bearing surface.
Consequences: Corrosion will cause the surface of the bronze bushing to become rough, increase friction, reduce load-bearing capacity, and eventually may cause bearing failure.
3. Overheating failure
Fault description: Overheating is usually caused by excessive bearing friction or poor lubrication. Overheating will cause the performance of the bronze bushing and the matching shaft material to deteriorate or even deform.
Cause:
Insufficient or inappropriate lubrication: The viscosity of the lubricant is too high or too low, and it cannot provide sufficient lubrication, resulting in increased friction and excessive heat.
Overload: The load borne by the bearing exceeds the designed load-bearing capacity, resulting in increased friction and overheating.
Excessive ambient temperature: The working environment temperature of the equipment is too high, which will also aggravate the overheating problem.
Consequences: Overheating can lead to increased wear of the bronze bushing and shaft, and even plastic deformation or bonding of the bushing material.
4. Bearing stuck or locked
Fault description: Sliding bearing stuck or locked is due to poor lubrication or foreign matter entering the sliding surface, which causes the bearing to fail to operate normally and causes excessive friction.
Cause:
Lubricant loss: Due to lack of lubricant or contamination, the bearing surface rubs dry, which increases friction and causes stuck.
Foreign matter entry: Dust, metal chips and other impurities enter the bearing surface, causing increased friction and excessive pressure.
Improper installation: Poor fit between the bronze bushing and the shaft or improper installation may also cause the bearing to get stuck.
Consequences: Stuck or locked may cause the equipment to fail to operate normally, and in severe cases may damage the bearing and related parts.
5. Fatigue cracks
Fault description: Fatigue cracks are caused by long-term high load or frequent start-stop, and the bearing material cracks under repeated stress.
Cause:
Long-term high-load operation: The bearing runs under high load for a long time, and the material is constantly subjected to pressure and friction, which is prone to fatigue cracks.
Impact load: Frequent start-stop or impact load of the equipment will cause fatigue cracks in the bronze bushing.
Consequences: Fatigue cracks will cause the strength of the bronze bushing to decrease or even break, affecting the stability and safety of the equipment.
6. Dimensional change
Fault description: During operation, the bronze bushing may change in size due to excessive wear, overheating or other reasons, including radial expansion or axial expansion.
Cause:
High temperature: High temperature will cause the bronze bushing material to expand or deform.
Overload: Excessive load will cause the bearing material to deform or squeeze, resulting in dimensional changes.
Consequences: Dimensional changes may cause the gap between the shaft and the bushing to increase or become uneven, thus affecting the accuracy and operating efficiency of the equipment.
7. Lubricating oil leakage
Fault description: Lubricating oil leakage is caused by poor sealing or installation problems of the bronze bushing, which prevents the lubricating oil from being properly distributed on the bearing surface, thereby affecting the lubrication effect.
Cause:
Aging of seals: Aging or damage of the seals of the bronze bushing leads to lubricating oil leakage.
Improper installation: The connection between the bushing and the shaft or external equipment is not tight, which may cause lubricating oil leakage.
Consequences: Lubricating oil leakage will lead to poor lubrication, increased friction and wear, and eventually bearing failure.
Summary:
As an important component of mechanical equipment, sliding bearings (bronze bushings) have many types of failures, covering a variety of problems such as wear, corrosion, overheating, seizure, cracks, etc. In order to ensure the long-term stable operation of the equipment, timely inspection and maintenance of bronze bushings are essential, including regular replacement of lubricating oil, inspection of seals, and avoidance of overload operation. Effective diagnosis and repair of different fault types can not only extend the service life of the bearing, but also avoid more serious damage to the equipment, reducing maintenance costs and downtime.
Related Reading：
Inspection requirements and precautions for bronze castings
Explore the production process and quality control of industrial bronze products
Bronze bushing characteristics and maintenance analysis
