When do you need to add lubricant to Flange Series Deep Groove Ball Bearing?

In industrial equipment and mechanical transmission systems, Flange Series Deep Groove Ball Bearing is widely used in key parts such as motors, pumps, conveyors, etc. due to its high load-bearing capacity, compact structure and easy installation. However, as the "lifeline" of bearing performance, the rational use of lubricants often becomes the core factor in determining the life and efficiency of equipment.
1. The core role of lubricants: Why must we pay attention to it?
The operation of deep groove ball bearings depends on the low-friction contact between the rolling elements (steel balls) and the inner and outer ring raceways. Lubricants have four core functions in this process:
Friction reduction and anti-wear: Forming an oil film on the contact surface, reducing direct friction between metals, and avoiding fretting wear.
Heat dissipation and cooling: The heat generated by friction is removed by the flow of lubricants to prevent the bearing from overheating and causing annealing or deformation of the material.
Anti-rust seal: Isolate pollutants such as moisture and dust, inhibit oxidation reactions, and extend the corrosion resistance of bearings.
Shock and noise reduction: reduce the impact vibration between rolling elements and cages, and improve the smoothness of equipment operation.
If lubrication fails, the bearing may pit, peel or even get stuck due to the sudden increase in friction coefficient, resulting in equipment downtime and soaring maintenance costs. According to statistics, more than 60% of early bearing failure cases are directly related to improper lubrication management (data source: ABMA American Bearing Manufacturers Association).
2. Critical timing of lubricant replenishment: five major judgment criteria
1. The severity of the operating environment and working conditions
High temperature environment (>80℃): grease base oil is easy to volatilize and oxidize, and the grease replenishment cycle needs to be shortened.
High load/high speed: friction heat generation is aggravated, and the lubricating film is easy to rupture. It is recommended to adopt a high-frequency micro-replenishment strategy.
Dusty and humid environment: pollutants are easy to invade the bearing cavity, and a dynamic sealing barrier needs to be formed through lubricants.
2. Physical manifestations of lubricant performance degradation
Color change: If the grease is black and agglomerated, it indicates serious oxidation or contamination.
Abnormal viscosity: The fluidity of the lubricating oil is significantly reduced or colloidal precipitation occurs, and it needs to be replaced immediately.
Noise and vibration: abnormal noise or vibration amplitude exceeding the standard (such as ISO 10816 standard) during bearing operation indicates insufficient lubrication.
3. Scientific planning of equipment maintenance cycle
Initial lubrication cycle: The pre-grease applied to new bearings at the factory usually only meets the initial running-in requirements. It is recommended to refill for the first time after 500 hours of operation.
Regular maintenance cycle: refer to the equipment manual and adjust according to the actual working conditions. For example, motor bearings need to be relubricated every 2000-8000 hours under standard load (according to SKF lubrication guidelines).
4. Quantitative evaluation of lubricant consumption
Grease lubrication: The filling amount should account for 30%-50% of the free space inside the bearing (excessive amount will cause temperature rise).
Oil lubrication: monitor oil loss through oil level gauge or flow sensor to ensure that the oil film continuously covers the contact surface.
5. Application of technical monitoring methods
Infrared thermal imager: detect local overheating areas of bearings (temperature difference >15℃ requires early warning).
Vibration analyzer: capture characteristic frequency anomalies caused by poor lubrication.
Oil particle counter: Analyze the degree of lubricant contamination and determine whether it needs to be replaced.
3. Correct lubrication method: Avoid four major misunderstandings
Even if the lubrication time is clear, improper operation may still be counterproductive. The following are common misunderstandings and solutions:
Misunderstanding 1: The more lubricant, the better
Excessive lubrication will increase the internal pressure of the bearing, hinder heat dissipation, and accelerate aging.
Solution: Use a quantitative grease gun and follow the principle of "small amounts and multiple times".
Misunderstanding 2: Mixing lubricants of different brands or types
Grease with different formulas may react chemically, resulting in agglomeration or oil separation.
Solution: Clean the old grease and then add new grease, or choose compatible products (such as the same NLGI grade).
Misunderstanding 3: Ignoring cleaning operations
Particles brought in during grease injection will scratch the raceway surface.
Solution: Clean the grease nozzle and surrounding areas before grease injection, and use special cleaning tools.
Misunderstanding 4: Relying on experience and ignoring data
Judging lubrication needs based on "feeling" alone can easily lead to excessive maintenance or insufficient lubrication.
Solution: Establish an equipment lubrication database and dynamically adjust strategies based on sensor data.