The reason of a stuck bearing

Many bearing application users have suffered the bearing stuck dilemma.

When the bearing is stuck, the next problem is to deal with a lot of disassembly difficulties. When the bearing is stuck on the axis, no matter how you knock on it, the bearing will move nowhere. In the end, the operator will be forced to check out the entire shaft then re-make a new axis. Such incidence comes out one after the other. To put it bluntly, it’s the matter how you choose the grease (indeed there are some other reasons of stuck bearing, like improper assembly). The crux of the matter is failed lubrication. However, poor lubrication will at the most cause abnormal bearing function due to wear and friction, but will not be stuck. The inapplicable grease filled in the bearing is the culprit of the stuck.

There’s a kind of non-soap grease (commonly known as non-drip butter) adsorbed by Bentonite is widely loved by users in the market. The sellers often flaunt its high-temperature property. Bentonite is widely used; even in the toothpaste we use every day. In brief, it’s a highly plastic, highly expansive clay mine. The main component is formed by the small crystals weathered by the formation of mineral rock, mostly in North America and Europe origin distribution and continental Europe. Bentonite grease features highly absorbent, which brings out high dropping point (usually each to 260°C), and so the working temperature is recommended under 200°C. Normally the seller will offer Bentonite grease when the customer asks for the grease durable for high temperature due to its high-temperature property. It will not drip even burning by the flame, that’s why it’s the best recommendation.

However, bentonite will carbonize under high temperature and high pressure after a long-term operation due to the degradation and failure of the base oil. More seriously, it will build carbon after combining with metals, and then it will result in stuck bearing. Normally, the seller will not tell the user in advance about this potential crisis. Why is the bentonite grease made and sold? The bentonite grease not only features with high-temp resistance, but also water-scouring resistance, that’s why it’s widely used by the paper industry, dyeing and finishing industry which are in high humidity environment, and steelmaking industry with high temp and high humidity environment.

Therefore, some industries like pharmaceutical, cosmetics, textile industry and so on, they don’t allow oil pollution, use bentonite grease because of its “non-dropping” property. However, it requires regular lubrication to avoid the grease has degraded. Are there other greases that can replace bentonite grease? If the operator cannot change the shaft grease regularly, it’s recommended to use “urea soap grease”.

In Europe and Japan, this kind of grease has been marketing for 10-20 years, and the selling is in growth every year. The sale in Japan is on the top of the world, and is mostly in auto industry. Pneumatic and electrical tools of Taiwan are sold globally. However, due to the limitation of short service life, the sale never goes beyond the similar products in Europe, America and Japan. It may be helpful if we replace it with “urea soap grease”.