Method of Judging Grease Metamorphism

In order to provide better performance, the bearings are lubricated by lubricating grease, which can reduce the friction and temperature of the bearings, if the grease is bad. Not only does not play a related role, but is more adverse to the use of bearings, so we must learn how to buy grease to tell whether the grease has deteriorated.

  

Method of judging grease metamorphism

1. Oil flow observation method

    Take two measuring cups , one of the lubricating oil to be inspected , the other empty on the desktop , lift the measuring cup full of lubricating oil away from the table top 30 - 40 cm and tilt , let the lubricating oil slowly flow into the empty cup , observe the flowing condition , the quality good lubricating oil oil flow should be slender , uniform and continuous , if the oil flow is lost or slow , and there is large flow of oil , the lubricating oil has deteriorated .

2. Hand twisting

    Twisting lubricating oil between thumb and index finger repeatedly grinding, a better lubricating oil hand feel lubricity, less debris, no friction, if feel the sand between fingers such as a greater sense of friction, it shows that there are many impurities in the lubricating oil. New lubricating oil should be replaced if it cannot be used again.

3.Illumination method

     On sunny days, use a screwdriver to lift the lubricating oil at an angle of 45 degrees to the horizontal level. Compare the sunlight and observe the oil droplets. Under light, you can clearly see that the lubricating oil is good without debris and can continue to function. If there is too much debris, replace the lubricating oil.

4. Oil drop trace method

    Take a clean white filter paper, drop a few drops on the filter paper, after oil leakage, if the surface of black powder, with the hand touch has a sense of resistance, then the lubricating oil has a lot of impurities. Good lubricating oil without powder, touch dry and smooth with hands, and yellow marks.

Method of Judging Grease Metamorphism

In order to provide better performance, the bearings are lubricated by lubricating grease, which can reduce the friction and temperature of the bearings, if the grease is bad. Not only does not play a related role, but is more adverse to the use of bearings, so we must learn how to buy grease to tell whether the grease has deteriorated.

  

Method of judging grease metamorphism

1. Oil flow observation method

    Take two measuring cups , one of the lubricating oil to be inspected , the other empty on the desktop , lift the measuring cup full of lubricating oil away from the table top 30 - 40 cm and tilt , let the lubricating oil slowly flow into the empty cup , observe the flowing condition , the quality good lubricating oil oil flow should be slender , uniform and continuous , if the oil flow is lost or slow , and there is large flow of oil , the lubricating oil has deteriorated .

2. Hand twisting

    Twisting lubricating oil between thumb and index finger repeatedly grinding, a better lubricating oil hand feel lubricity, less debris, no friction, if feel the sand between fingers such as a greater sense of friction, it shows that there are many impurities in the lubricating oil. New lubricating oil should be replaced if it cannot be used again.

3.Illumination method

     On sunny days, use a screwdriver to lift the lubricating oil at an angle of 45 degrees to the horizontal level. Compare the sunlight and observe the oil droplets. Under light, you can clearly see that the lubricating oil is good without debris and can continue to function. If there is too much debris, replace the lubricating oil.

4. Oil drop trace method

    Take a clean white filter paper, drop a few drops on the filter paper, after oil leakage, if the surface of black powder, with the hand touch has a sense of resistance, then the lubricating oil has a lot of impurities. Good lubricating oil without powder, touch dry and smooth with hands, and yellow marks.

High temperature adaptability of bearings

The high temperature adaptability of the bearing and the heat treatment process of the bearing within an outer diameter of  240 mm ensure that it is dimensionally stable below 150 degrees. Special heat treatments are required if the operating temperature is above 150 degrees. These bearings are marked with the suffixes S1 to S4 (DIN 623).

S1: Maximum operating temperature 200 degrees

S2: Maximum operating temperature 250 degrees

S3: Maximum working temperature 300 degrees

S4: Maximum operating temperature 350 degrees

Bearings with an outer diameter＞240 mm are generally stable at temperatures below 200 degrees. The bearings use the cages made of glass fiber reinforced nylon 66 and can be stably operated at working temperatures below 120 degrees. When this kind of bearing is lubricated with oil, if the oil contains additives, the life of the cage may be shortened. When the temperature exceeds 120 degrees, the aged lubricant will also shorten the life of the cage. Therefore, you should pay attention to observe and replace the lubricant as scheduled.

The allowable temperature of sealed bearing also depends on the filled grease and the requirements of the contact seal. Sealed bearings are lubricated with specially tested high quality lithium grease. This grease can withstand high temperatures of 120 degrees in a short time. If the stable operating temperature reaches 70 degrees or higher, the life of standard lithium grease will be shortened.

ZYS has special technical team to develop the lubricant to meet the different kinds of bearing. If you want to know more, please check http://www.zys-bearings.com/bearing-materials/lubricant/antirust-oil-for-bearing.html.

The importance of lubricant on bearing torque

Rolling element bearings, such as ball bearing and roller bearings, support the load required to carry out a machine’s function at a much lower friction than a fluid bearing alternative. This reduces the power required to drive the equipment, lowering the cost of moving the load and the energy required to operate the equipment.
Bearing torque is the force required to overcome internal friction to start or maintain rotation of the bearing. This frictional torque is generally increased with a larger bearing, increased load or increased lubricant drag.

How can we get the right bearing torque?
Many applications require the bearing to spin easily with extremely low frictional torque, without generating excess heat. Dry lubricant is one way of meeting these low torque requirements. Despite being solid, dry lubricants can reduce friction between two surfaces without the need for oil or grease.
Instrument oils are another option for low torque requirements. They will often produce very low torque levels especially at very low speeds.

There are many oils and greases to choose from, and there are other factors to consider aside from torque, such as contamination, speed or corrosion resistance. With the right lubrication type, correct fill level and consideration of load, you’ll be able to source bearings with the correct frictional torque for the specific application.