slewing bearing soft belt installation skills
June 14, 2019slewing bearing for marine crane
June 18, 2019
- Before installing the slewing bearing (turntable bearing), first we have to examine the installation surface. This requires that the bearing has enough stiffness. The connection surface should be made mechanically. The surface is flat without debris and burrs. If the required flatness can not be achieved by mechanical processing, it is allowed to inject special plastics of great stiffness to ensure the accuracy of the flatness, thus reduce vibration. In the ring of the slewing bearing , there is always a soft zone which is marked with the “S”. When installing, the soft zone should be positioned in the in the non-load area or non-constant load area (plug holes are always located at the soft zone).
- When installing the slewing bearing (turntable bearing), first we should make the radial-positioning ,the mounting bolts should be cross-tightened. And the swing of the slewing bearing should be checked. To ensure a smooth bearing drive, the gears should be engaged before the mounting bolts are tightened. The bolt should have sufficient pretension force when tightening, and the pretension force should be 70% of the yield limit of the bolt material. The mounting bolts should be fitted with a leveling washer, and spring washers are strictly prohibited. After the installation of the turntable bearings, it will be put into operation. After 100 hours of continuous operation, we should carry out a comprehensive check of the installation bolts of the pre-tight torque to see if it still meets the requirements. Afterwards, we should carry out the above-mentioned inspection every 500 hours.
- The slewing bearing (turntable bearing) should be filled with the appropriate amount of grease after installation. The lubricant grease should be filled when the slewing bearing is swinging, in order to make the grease evenly distributed. After a period of work, the turntable bearings will inevitably lose part of the grease. Therefore, in normal operation, the turntable bearing should be replenished grease every 50 to 100 hours. In high temperature environments or dusty conditions, the cycle of adding grease should be appropriately short. When the machine is to be stopped and sealed, it must also be filled with sufficient grease.
- The packaging, transportation and storage of the slewing bearing (turntable bearings): before packaging, the slewing bearing needs to be applied dual-use grease of anti-rust and lubrication on its inner and outer raceway. We should wrap the slewing bearing in plastic film, composite kraft paper, and then industrial wrapping belt for internal packaging. The outer packaging adopts special wooden boxes or iron boxes.
- Bearings in the transport process, should be placed horizontally on the means of transport. There should be anti-slip and anti-vibration prevention measures and, if necessary, auxiliary support.Bearings shall be placed
- horizontally on a dry, ventilated and flat field and stored in isolation from chemicals and other corrosive substances. If multiple sets of bearings need to be stacked overlapped, we need to place three or more wooden pad blocks evenly in the direction of the circumference between each two sets. The position of the upper and lower layers of the pad should be placed consistently. Bearings that need to be stored beyond the rust-proof period should be re-cleaned and applied rust-proofing.
