The seal gap between the moving spinner and stationary tub (bowl) allows the process water, particles and any contaminants to be carried out of the bowl so the process can operate and perform to its optimum capability consistently.
This gap must be monitored on a regular basis, weekly or even daily depending on the nature of the process consumables and parts being treated. If unchecked the gap can open up through wear to a size where media and parts can enter the gap which will cause premature part failure and necessitate replacement. You are also subjecting your parts to a high risk of damage when this occurs, especially if a part gets into the gap when it can come in to contact with moving parts around it. Equally, where heat builds up in the machine polyurethane is subject to expansion and should this occur to the point where the gap closes between the tub and spinner there is a risk of damage to the gearbox and motor for the machine. So the gap should be checked regularly to ensure it has neither opened nor closed and if found to have done so the gap needs to be reset accordingly.
On larger machines Rősler incorporate temperature probes which detect if heat is building in the process bowl and will stop the machine as a preventative measure. This is a standard feature to ensure maximum tub and spinner lifetime are achieved. In the case of the gap narrowing the water level in the bowl will increase, with compound added this can create foam (and mess) and the process time and surface finish will again suffer as a result. If the quantity of particles in the bowl is high then this can contaminate (and even ruin the media) as well as coating the lining of the bowl causing a loss in drive of the media.
For more information on Centrifugal Disc Finishing please visit www.rosler.com
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