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What kind of lubricant is used for different reducers?

What kind of lubricant is used for different reducers?

Nov 21,2019

What kind of lubricant is used in the reducer?

1. The horizontal cycloid reducer is lubricated under normal conditions by oil pool. The height of the oil surface can be kept in the middle of the oil window. Cyclic lubrication can be used when the working environment is at a high temperature.

 

2. The cycloidal pinwheel reducer is generally lubricated with 40# or 50# mechanical oil at normal temperature. In order to improve the performance of the reducer and extend the service life of the cycloid reducer, it is recommended to use 70# or 90# extreme pressure gears oil. Lubricants should also be reconsidered when working at high or low temperatures.

 

3. The vertical installation of the planetary cycloid reducer should strictly prevent the oil pump from breaking oil to avoid damage to the components of the reducer.

 

4. When refueling, you can rotate the vent cap on the upper part of the base to refuel. When draining oil, screw the oil drain plug on the lower part of the base to release the oil. The reducer is internally oil-free.

 

5, the first refueling operation for 100 hours should be replaced with new oil, (and clean the internal dirty oil) and then continue to work, change every six months (8-hour work system), if the working conditions are bad, the oil change time can be shortened properly, Practice has proved that the frequent cleaning and oil change of the reducer (such as 36 months) plays an important role in extending the service life of the reducer. Lubricating oil should always be replenished during use.

 

Reducer lubricating oil performance characteristics

1, with good wear resistance

Anti-wear property refers to the ability of the reducer lubricating oil to form and maintain the oil film on the friction surface between the moving parts, preventing the metal from contacting each other and reducing the wear. The wear resistance of the reducer lubricant is mainly determined by the oiliness and extreme pressure (shear resistance).

Oiliness refers to the ability of gear oil to adsorb on the friction surface of a part to form an oil film to reduce and wear. Generally speaking, the good oiliness of gear oil means that it has strong adsorption capacity and can improve the wear resistance.

Extreme pressure is the ability to prevent damage to the friction surface due to sintering, gluing, etc. under extremely high pressure lubrication conditions where the contact pressure of the surface is very high and the oil film is prone to cracking.

 

2, viscosity and viscosity temperature

The reducer lubricant must have a suitable viscosity and good viscosity.

In general, the use of high-viscosity lubricating oil is advantageous for preventing damage to the machine parts and reducing noise, while the transmission system efficiency, cooling effect and oil transferability are good for low-viscosity lubricating oil.

For the viscosity-temperature performance, although the lubricating oil of the reducer does not have the same temperature change as the engine oil, it also requires good viscosity-temperature performance due to its large tooth surface pressure, especially when used in cold regions. Failure to do so may result in increased wear and increased fuel consumption.

 

3. Oxidation stability

The lubricating oil of the reducer is subjected to the stirring and falling of the gear, and the constant contact with the oxygen, forming various oxides under the catalytic action of the metal, so that the viscosity of the lubricating oil is increased, the color is deepened, the acid value is increased, and the precipitate is increased. The color becomes darker and causes corrosion of the machine parts, resulting in deterioration of the foam resistance and oxidation resistance of the lubricating oil, and thus the lubricating oil has to be replaced.

Lubricating oil with good oxidation stability will last for a long time. Therefore, antioxidants are usually added to the lubricating oil to improve oxidation stability.

 

4, Anti-corrosion and anti-corrosion

Rust prevention refers to the performance of the reducer lubricant to prevent metal rust. Corrosion resistance refers to the performance of gear oil to prevent metal corrosion.

The rust of metal parts is mainly caused by the presence of oxygen and water in the lubricating oil. The corrosion is caused by acid and sulfide in the oil. Anti-additives and anti-corrosion additives are usually added to the reducer lubricating oil to improve.

 

5, Anti-foaming

The reducer lubricant produces a lot of small bubbles when the gear is moving under intense agitation. If the small bubbles disappear quickly, it will not affect the use. If the stable foam is no longer lost and emulsified and deteriorated, overflow will occur on the tooth surface, destroying the lubricating oil film and aggravating wear.

 

Reducer lubricating oil selection principle 

The primary factor in the choice of reducer lubricants is viscosity. Viscosity is a very important physical and chemical index of gear oil. The meshing speed of the gear is the main indicator of viscosity selection. The viscosity of the gear oil of the suitable reducer can make the internal friction of the lubricating oil small, so that the gear surface damage and transmission noise and vibration are greatly reduced.

 

The viscosity of the reducer lubricant is mainly achieved by the base oil and viscosity index improver. A good adhesive agent not only requires high cohesive ability and good shear stability, but also requires good low temperature performance and thermal oxidation stability. The viscous finger enthalpy with poor shear stability has a series of effects on wear and fuel consumption due to the fracture of the main chain of the polymer under shear stress and the decrease in molecular weight, which makes the oil thin. For lubricating oils of the same viscosity grade, if non-refined base oils and not very good adhesives are used, although they can be adjusted to achieve a certain viscosity standard, the properties such as viscosity temperature and shear stability are not good. , also does not reach the expected period of use. Therefore, for low-speed heavy-duty cement reducers, try to avoid the use of such lubricants, and choose high-quality high-grade lubricants, because its base oil and adhesives are better.

 

The greater the viscosity of the gear oil, the stronger the protection against the various damage of the tooth surface, and therefore the lower the wear of the reducer. However, the viscosity is too large, and the abrasive grains are not easily precipitated, which reduces the flushing action and the endothermic cooling effect of the lubricating oil on the tooth surface, resulting in poor lubrication. At the same time, the abrasive particles suspended in the sleeve enter the meshing zone, which is easy to cause abrasive wear. In addition, if the viscosity is too large, the transmission resistance is increased, the tooth surface temperature is increased, and the power consumption is increased. In general, the viscosity is increased by one grade, the energy consumption is increased by about 1% to 5%, and the stability and anti-emulsification properties of the oil are all lowered. However, high viscosity has obvious benefits in reducing noise and preventing oil leakage. In addition, equipment with uneven load, frequent start-up and operation in high temperature environments should have a slightly higher viscosity. In summary, the speed reducer should use high-grade lubricating oil of suitable viscosity. For large speed reducers with low speed and heavy load, extreme pressure type heavy duty gear oil should be used as much as possible because it has better extreme pressure wear resistance, thermal oxidation stability, corrosion protection and prevention than medium load gear oil. Rust and excellent anti-emulsification properties make it easy to form a chemical film on the meshing surface of the gear, thereby protecting the tooth surface and minimizing the wear of the reducer.

 

Reducer lubricating oil use precautions

1.For the reducer system with concentrated lubrication of thin oil, due to the strict requirements of the temperature of the lubricating oil or the tank, it is usually cooled by a cooler (steam cooling) or a cooling coil (water cooling). Although the gear oil is required to have better anti-emulsification performance, after the oil penetrates into a considerable amount of water, the oil is easily emulsified. After the gear oil with the extreme pressure anti-wear agent is emulsified, the additive is hydrolyzed or precipitated and lost. It has the property and produces harmful substances, which makes the gear oil deteriorate rapidly and lose its performance. Zeayeto reminds everyone that emulsified oils must never be used. For water (or steam) cooling lubrication systems, care must be taken to prevent water (steam) leakage to avoid unnecessary damage to the reducer.

2. For the reducer system that uses the pump for circulating lubrication, pay attention to the pressure difference of the pump and clean the filter in time. If the pressure difference of the pump is large in a short time, or the frequency of cleaning the filter screen is obviously increased, and the sludge and metal grinding shoulder on the filter net are obviously increased, it means that the use state of the lubricating oil is not very good. In addition to the problems of materials and design, it can be said that the lubricating oil is not reasonable enough: first, the viscosity is not suitable enough, and second, the heavy load can be used instead of the medium load, that is, the gear oil of the first grade is selected, and the effect will be obviously improved.

 

3. It is necessary to avoid mixing the new oil into the old oil (rather than replenishing the oil as required), or adding a high viscosity oil to reduce the viscosity but to achieve a certain viscosity. In doing so, there may be some short-term effects, but the performance of the oil will be significantly reduced, and the lubrication conditions of the equipment will be deteriorated, resulting in increased wear and tear, which will shorten the service life of the equipment in a certain sense. In addition, it may be because the main agent is different, the additive "fighting" occurs when mixing, so that the effects of the additives cancel each other, and the consequences on the equipment are unimaginable.

 

4. Regarding the problem of replacing the oil cycle, theoretically speaking, the oil change period is short, which can better reduce the friction loss and prolong the service life of the equipment, and at the same time provide a necessary condition for ensuring its normal operation. However, from the perspective of economic efficiency, oil products should be used more accurately and effectively. Whether to change the oil and when to change the oil, in addition to complying with the oil change period, it should also be based on factors such as the start-up time and operating rate of the equipment, so that the oil can be used to the maximum extent.

 

5. Regularly monitor the oil temperature, vibration, noise and other issues of the oil equipment. When the tooth surface is damaged due to poor lubrication conditions, the vibration and noise can be directly enhanced.