Slew Drive Maintenance

The Importance of Slew Drive Maintenance

Following basic care and material handling of mechanical components is a requirement if you want to extend the life of the slew drive bearings in your equipment. Appropriate maintenance will prolong the performance and lifetime of your machinery. 

 

How to Maintain and Enhance the Life of a Slew Drive

There are two steps to take when maintaining a slew drive — post-installation testing and greasing the slew drive bearings. These processes are both critical to extend the life of your bearings and prevent premature failure. Per the manufacturer's manual, slew drives should also be subject to inspection and maintenance after a specified number of operational hours. It is the user's responsibility to adhere to the requirements set by the manufacturer. 

 

1. Post-Installation Testing

Extending the life of your bearings starts the moment you install them. Pay close attention to the mounting structure and mounting procedure you use while installing the slew drive. Post-installation testing is critical to ensure that the slew ring achieves a smooth and free rotation through the worm input. The assemblers must inspect the worm-wheel mesh to verify that its action is smooth while rotating across different angles. In standard applications, slew drives are greased 40-60% and should be greased prior to the commissioning of the machine. 

You should perform post-installation testing after applying external loads to the drive. It is crucial to maintain speed in the 1 RPM range across all applications and sizes. For a worm-wheel mesh to generate the required high torques, speed must be kept at a minimum to prevent overheating the gear teeth and premature failure. 

Avoid surpassing recommended values for nominal and maximum torques. Overloading can result in teeth damage or "popping" the worm out of location. In more severe incidents, worms end up failing right at the center due to excessive loads.

 

2. Slew Bearing Greasing

The lubrication schedule must be followed with specified quantities according to the manufacturer's manual. A standard process to extend the life of your bearings is to grease slow-moving equipment after the first 50 hours of operation then periodically every 100 hours of use. Machinery that moves rapidly or at a continuous rate requires more frequent greasing. When in doubt, it is better to apply more lubrication. A slew drive can never be “over-greased," but not greasing enough can cause premature failure.

You should lubricate the bearings with heavy-duty, extreme-pressure grease to make sure they do not dry out. Bearings with dried-out grease will accumulate condensation. Apply the grease while rotating the bearings to spread it evenly.

The inner raceway has a slew ring as a main component, so the same procedure of greasing needs to be followed to spread grease across all internal rolling elements. This can be performed using the grease zerks in the internal diameter or the top service of the slew ring. While greasing, the worm should rotate constantly to turn the slew ring 360 degrees to ensure grease reaches all the internal rolling elements. Furthermore, it is vital to inject grease in the worm-wheel mesh to prevent overheating due to friction. The worm shaft is suspended inside the housing using two conical bearings that require grease on scheduled intervals as well.

Not performing post-installation testing or greasing may result in early slew bearing failure. Grinding, popping and clicking sounds are indications that the gears should be lubricated or tested. With proper slew drive maintenance, you can extend the life of your bearings.

 

North America's Top Slew Drive Manufacturer

SlewMaster Inc. will provide you with custom solutions for all of your rotary-based applications while working hand-in-hand with your engineers. The level of control we have over our processes sets us apart from other competitors in the slewing industry. We are invested in providing the highest quality products along with industry-leading customer service to satisfy our customers.

Contact us today for a free consultation and learn more about how we can help you!