Lubrication and its importance when using worm gear motors

If there's one reason behind the abundant use of worm gear motors it's their tendency to provide a high reduction ratio with minimal effort.

This means fewer moving parts and, therefore, lower chances of failure.

To put this in perspective, coventional gearsets can take several reductions to achieve an equal reduction level that a worm gear provides. Nevertheless, there is one particular challenge to overcome when using worm gears: lubrication. The worm and the wheel gear faces slide together as they move, and since there are no rolling parts that are employed for the interaction of these two moving parts it can be troublesome to lubricate.

Proper selection protocol

Worm gear motors rely on high lubricant viscosity – these can be challenging to filter and, as a result, the oils used for lubrication are specially made. Lubrication is crucial due to how the gears work, i.e. in a spiral motion; this kind of movement results in an issue reffered to as sliding wear – a byproduct of sliding friction. This challenge confines the workarounds that would otherwise be available as sliding motion is the only means in which a worm gear can transfer power in an effective manner; thus, proper lubrication is needed.

Avoiding lubrication wear

Sliding movement can lead to the lubrication wearing off. In a typical gear tooth, the sliding or rolling friction between the gear tooth apex and moving parts occur at a low velocity. In worm gear motors, as the worm surface leaves the wheel surface, more lubricant is peeled away and this same process occurs again on the next revolution.

Aforementioned reasons like these are why you must take the necessary precautions in selecting the right lubricant if you are to overcome any sliding issues. If your application calls for the use of worm gear you will be best served in using a lubricant film thickness that is good enough to handle the full load of the gear.