Precisely Matching Operating Conditions: Core Strategies and a Practical Guide to Sliding Bearing Selection
In mechanical transmission systems, radial sliding bearings are key components supporting rotating shafts. The rationality of their selection directly impacts the stability and lifespan of the equipment. Faced with diverse operating conditions, how can we make informed decisions to avoid overkill or overkill?
This article provides a systematic selection approach based on three aspects: structural type, operating parameter matching, and material properties.
1. Classifying by Structure to Match Installation and Maintenance Requirements
Sliding bearings are primarily classified into three categories:
Integral: Compact and low-cost, suitable for light loads, low speeds, and applications requiring less frequent assembly and disassembly, such as small motors and household appliances.
Split: Easy to install and maintain axial positioning, widely used in medium-to-large equipment, such as gearboxes and compressors, requiring regular maintenance.
Self-aligning: Equipped with an automatic self-aligning function, it compensates for shaft deflection or installation deviation. It is suitable for long shafts or easily deformed structures and is commonly found in heavy machinery and marine propulsion systems.
2. Use characteristic curves to quickly identify bearing types
In engineering practice, a bearing selection characteristic curve is often used for preliminary screening. This chart uses journal speed as the horizontal axis and load per unit projected area as the vertical axis to divide the applicable ranges of different bearings. For example, for low speed and heavy load, liquid-lubricated bearings are preferred; for medium speed and medium load, split bearings with partial fluid lubrication are a common choice; for high speed and light load, self-lubricating or plastic bearings can be used to reduce friction and temperature rise. By consulting a table (such as the selection charts in industry standards), designers can quickly eliminate unsuitable types, improving selection efficiency.
3. Material performance comparison determines operational reliability
Different bearing materials are suitable for different operating environments: Powder metallurgy bearings: They are self-lubricating and suitable for oil-free or low-oil environments, but they have weak impact resistance and are mostly used in light-load, intermittent equipment. Plastic bearings (such as POM and PTFE-based bearings): They are corrosion-resistant, low-noise, and require no lubrication, but have poor thermal stability and are suitable for humid, clean environments, or food processing. Babbitt-lined bearings: They offer strong load capacity and excellent compliance, making them the preferred choice for heavy-load, low-speed equipment. However, they are more expensive and require a lubrication system.
Sliding bearing selection isn't determined by a single parameter; it's a comprehensive trade-off between structural type, operating conditions, and material properties. Designers are advised to use selection charts to conduct preliminary screening based on specific speeds, loads, space constraints, and maintenance cycles. Then, they should compare material properties to ultimately determine the optimal solution. For beginners, mastering this systematic process can significantly improve design efficiency and reliability.
Post time: Nov-24-2025
