Lubricants and grease which is different? Xiaobian here for everyone to summarize the following differences:
When the frictional part is at a standstill, the grease retains its original shape and will not be lost automatically due to gravity, nor will it slip off and leak from vertical surfaces. This feature is ideal for stop-and-start or infrequent friction sites, very difficult locations for grease filling materials such as Crane Airline Lubrication, and open or poorly sealed locations. When the friction part is in motion, the grease does not slip out of the way of a centrifugal force like a lubricating oil and will not spill out from a poorly sealed area. Some dripping or splashing is almost completely avoided, thus ensuring that the environment is protected from or less contaminated, and also from contamination of the product. This point is especially important for industries like papermaking, weaving and foodstuffs.
2. Operating temperature range
Grease operating temperature range wider than the lubricating oil. For example, universal lithium grease can be used in the temperature range of -20 ~ 120 ℃, the general calcium or sodium grease is also used at -20 ~ 60 ℃ or -20 ~ 120 ℃. However, a certain grade of lubricant uses a much narrower temperature range.
3. Pressure resistance
Grease on the metal surface adsorption capacity is much larger than the lubricating oil, and can form a relatively solid film, withstand higher work load, which is due to the grease contains a large number of polar substances results. In addition, as a base fat, when adding polar additives, the sensibility is also better than the lubricating oil.
4 service life
Long-term use without replacement grease, lubrication can still guarantee the role, because the real role of lubrication is only a small part of the friction near the surface of the grease, but also rely on the impact of soap fiber circulation lubrication, we can see a very long life; Lubricating oil often need to add, or recycling oil, or can not guarantee the normal lubrication of machinery. In terms of quantity, the consumption of lubricating oil is 15 to 20 times more than that of lubricating grease, so lubricating parts with lubricating grease is much more than that of lubricating oil. Such as automobile lubrication parts, using grease about 2/3 strong. On the other hand, due to infrequent refueling, long service intervals, lower consumption and lower maintenance costs.
5. Lubrication equipment structure
Constructed with grease lubricated equipment is relatively simple, this can simplify the design and reduce investment. In addition, the lubrication system occupies a relatively small footprint and the lubrication points are very flexible and save maintenance and management costs when in operation. Some precision instruments, instruments and electronic devices such as a very small space does not allow dedicated lubrication system, the need for long life or often rely on grease lubrication for life. However, the lubricating oil needs to be lubricated in a closed system. The structure of the lubricated equipment is also relatively complicated, and the investment and the area are also very large. Therefore, it is not suitable for use in a semi-closed or non-closed lubricating part.
6. Protective performance
Grease will not be lost from the surface of the guard automatically due to its own weight and will retain its ability to retain grease. Generally, greases are thicker than the reservoir and thus have a greater ability to prevent water or water vapor from penetrating the metal surface. Can be isolated from acids, alkalis, moisture, oxygen and water to directly etch the work surface. Some greases are not dissolved by chemicals, basic organic materials, fuels and lubricants. The protection of lubricants is relatively poor, only in a short period of time play a protective role.
Grease prevents dust from entering the work surface, avoids the inclusion of impurities, and abrasion of mechanical parts. For such bearings as these spatial structure is more complex, the lubricating surface of the high precision parts, grease can block the dust on the outer surface of the bearing, and can fill the main gap, play a sealing effect. For some rough machinery such as agricultural tractors, harvesters, bulldozers, etc., the entire machinery is in contact with the earth, sand, and its rotating parts with grease lubrication, not only can play a lubricating effect, but also to some extent also play a sealing role . But lubricants do not have this ability.
8. cushioning shock
Due to its high viscosity and good oily properties, greases can be used in some lubricated parts that often require changes in direction of motion and high impact forces such as camshafts, universal joints, crushers, etc. To a certain cushioning effect. Greases also reduce noise on certain components, such as gear transmissions, but lubricants generally appear to be less bumpy and noise-reducing.