 |
bearing for mining |
10,22,2016 |
|
bearing in mining |
10,22,2016 |
|
bearing of mining |
10,22,2016 |
|
mining bearing |
10,22,2016 |
|
mining bearing |
10,22,2016 |
|
mining bearing |
10,22,2016 |
|
bearing for mining drum |
10,21,2016 |
|
bearing for mining drum |
10,21,2016 |
|
bearing for mining drum pulley |
10,21,2016 |
|
bearing for mining pulley |
10,21,2016 |
|
| Current Location：Home
- News |
Bearings should not add too much grease
|
| Time：2016.09.03 News Sources：Shandong Xinkaite bearing Co.,Ltd. Views：
|
We know that the grease has very good adhesion, abrasion resistance, heat resistance, rust resistance and lubricity can be improved oxidation resistance, anti-aging, can dissolve carbon deposits, prevent metal wear debris and oil knot together improve mechanical abrasion, pressure and corrosion resistance.
After bearing grease understand the movement, it will naturally come to a conclusion: bearing grease should not be excessive. Grease and more not only wasteful, but also harmful. The higher the speed of the bearing, the greater the harm.
Grease filling amount more, the greater the friction torque. The same amount of filling, sealed bearing friction torque is greater than the open bearings. Filling amount of grease inside the bearing space volume equivalent to 60% after the friction torque longer significantly increased. This is due to open in the bearing grease have been largely extruded and sealed bearing grease leakage has also been the reason.
With the increase of the amount of grease filling, linear bearing temperature increase, the same quantity of filling, sealed bearing temperature rise was higher than the open bearings.
Generally believed that the amount of grease filled sealed rolling bearing, a maximum of about 50% of the internal space. Shawki and Mokhtar tests showed that the ball bearing to 20-30% is most appropriate.
Bearing seals
To keep the internal seal is good lubrication and prevent the cooling water, iron oxide skin, impurities immersed in the working surface extending bearing life. Due to the high temperature roller bearing sealing problems, most bearing damage is close to the roll body side of the site, often because the bearing grease pollution, the loss of the parts work surface wear, spalling or chipping, so that the grease fail faster.
Bearing the seal comes into Seal and Two External. The main outer seal labyrinth and contact combination design. The more maze level (not less than two poles) the smaller the gap the better the seal. Take unilateral radial maze gap 0.6 ~ 1.5mm according to the size of bearing size; axial 4 ~ 6mm.
Contact oil seal: it used widely in the rolling mill, in order to increase the effect it can twenty-three used in parallel. Directional seal, can not hold against. Hot rolling mill generally installed two seals, two lip seals have to outer bearing, in order to prevent outside dirt ingress. Cold strip mill is typically mounted within a three seals near the bearing oil seal lip would like to prevent grease spillover effects rolled quality. Be careful when using the seal to avoid crashing when loading roll lip, affect the sealing effect.
RBR-ring: This is a rolling bearing special rubber lip seal ring, it has been widely used in recent years. RBR seal ring with axial sealing manner, the lip attached to the base surface of the gland, not affected by the rolling roll beat, the old grease inside the bearing can overflow, external cooling water, iron oxide skin, impurities are blocked lip enter, there is a good seal. And easy to use, roll into the bearing housing are not affected when changing rolls.
How to extend bearing life and / or performance?
First, the lubrication is critical. Select the appropriate lubrication system and high-quality lubricants. The oil film bearing and oil film due to surface contact with each other separated, and provide the necessary protection for corrosion and wear, so all rotating or reciprocating movement of parts, especially in terms of bearings and gears, for normal operation, the oil film can not be or missing. As for the splash lubrication or lubrication system, the oil film can transfer heat. Factories often due to improper lubrication unnecessary downtime and equipment status deterioration. Oil shortage will lead to increased wear and temperature rise, causing excessive wear and / or bearing damage and early failure. Excessive lubrication, especially high-speed operation of the device, because of the oil agitation and excessive heat, chemical degradation of the lubricant, can lead to bearing damage.
Proper lubrication, regular maintenance can avoid bearing damage due to lubrication problems caused. Ensure reasonable lubrication should be done:
• Follow the device manufacturer for each device set Guide;
• When the grease, it should be filled with rolling bearing parts and housing (or retainer) between, in order to ensure a sufficient amount of grease into the key raceway surface sufficiently lubricated;
• Note that when the bearings should be greasing (Re-lubrication);
• monitoring equipment equipment indicating instrument for early detection of signs of problems, such as temperature fluctuations and / or abnormally high temperature;
• Note that noise or abnormal vibration equipment;
• observe the leakage of lubricating oil;
• regular lubricant samples and check for contamination.
Secondly, To improve bearing performance and reasonable adjustment is very important. Assembly or installation, the bearing internal gap is too large or too small, or in some cases, the pre-load is too high, it may lead to early bearing damage and shortened life expectancy. In addition to downtime and costly repairs, the bearing assembly and improper installation may have more negative effects, such as the impact the operation of other parts and shorten its service life.
According to the device manufacturers instruction manual, assembly, installation and regular maintenance is the best way to prevent problems arising. If time is tight, you can adjust the device before pushing or remove shims to correct over-tapered rolling bearings set loose. On the other hand, bearing adjustment too tight, it may result in overheating damage, we had to replace the bearings. Bearing assembling step must be accurate, repeatable, and can be verified after the installation is complete. You must also consider other part parameters to optimize system performance.
In addition, in accordance with OEM requirements to use the device, set the appropriate predictive maintenance items, such as monitoring of oil or grease, which should include root cause analysis. Thus, even if the device in question, its uptime can be greatly extended.
Proper lubrication and maintenance is critical to proper installation and use are indispensable, and then make full use of existing equipment condition monitoring escort. Failure to follow installation and maintenance requirements will result in equipment failure, constitute a major safety hazard.
|
|
|
