excavator slewing bearings

Slewing bearings are widely used in excavators. Recently, many friends have come to inquire about the oil leakage of excavator slewing bearings. Today, the editor will talk about how to deal with it, and share the experience of repairing and handling.

When the excavator is in use, lubricating oil often leaks out of the bearings, and the leaked oil and butter mix together and it is difficult to distinguish the type! How can I tell which oil is leaking out?

The first step is to check whether the gear oil level of the rotary gear box is lower limit or high tide. If the gear oil level drops or there is basically no oil level, it can be directly determined that the grinding disc oil seal under the rotary gear box is damaged.

Remedy: Check whether the reduction gear box gear is damaged. If the reduction gear is normal, check whether the clearance between the upper and lower bearings of the rotary vertical shaft or the bearing seat is too large. If there is any problem, replace the bearing or repair the bearing seat shell! Check whether the contact surface between the oil seal and the vertical shaft is severely worn. If necessary, cut the oil seal lip spring appropriately to increase the tightness of the oil seal or change the position of the oil seal lip!

If the oil level in the rotary tooth box increases significantly, it can basically be concluded that the oil seal of the rotary motor skeleton is damaged, because the hydraulic oil in the motor is connected to the tooth box through the pressure to the lower tooth box. The pressure in the tooth box is too high to damage the oil seal of the grinding disc, so the motor skeleton must be replaced at the same time And the grinding disc oil seal! When disassembling the motor, carefully check whether the bearing of the upper cover of the motor shaft is too large, which causes the centrifugal rotation of the motor shaft to rotate and damage the oil seal!

If the oil level in the rotary tooth box is normal, then the oil seal of the rotary center joint is damaged! The most obvious symptom is insufficient power to walk on one or both sides!

Remedy: Replace the oil seal inside, and check whether the contact surface of the first oil seal on the shaft is worn! If the abrasion is severe, it must be repaired. If it is not repaired, it will be futile even if the oil seal is replaced. Because the cost of replacing the shaft is too high, it is usually repaired, and it can be used normally after the sleeve or repair welding and then polishing.

If the above three causes are eliminated, there is another possibility that the sealing ring of the main support bearing of the slewing ring is damaged! The only thing that leaked out was the butter, because the viscosity of the butter was relatively high and it was easy to distinguish it.

Some friends think that you don’t like to miss some butter, so they don’t pay much attention to it! But here to tell everyone that this oil seal not only plays a role in sealing oil, but also plays a role in dust prevention! Because most of the working environment of the excavator is in the sand and rock field, it is inevitable that debris will be mixed into the bearing to cause early wear of the slewing bearing, which directly affects the service life of the turntable! Although it is troublesome to replace, it is recommended to replace it in time for your car.