Background
During a strip marking investigation at an aluminium plant, Vibremo engineers identified a resonant issue occurring on a grinding machine when grinding intermediate rolls. During grinding, a sharp and unstable vibration was measured within a specific frequency range, leading to marking on the rolls.
We carried out resonance testing, which allowed us to trace the issue to the roll steadies, with the marking frequency observed during operational measurements matching their resonance.
Solution
We worked with the clients’ maintenance team onsite to make structural changes to the steadies. The shape of the steady rests was changed from curved to flat, resulting in lines of contact with the roll.
Resonance testing was carried out again after the modification, showing that the resonance observed with the curved steady rests split into two separate resonances with significantly lower amplitudes after switching to flat steady rests.
Outcome
During grinding, it was found that the modifications to the steady rests completely eliminated the resonance issue. The vibration levels were significantly lower at the resonant frequency when using the same grinding conditions and the grinding machine was able to produce chatter free rolls!
Vibremo recommended that the client maintain flat steady rests, either by regularly cycling in new rests or by scraping the existing rests to maintain the flat edge.
"It can be surprising how seemingly small changes to a much larger system can affect overall machine performance. Examples like this show that with the right measurement tools and knowledgeable engineers, small details can make a massive improvement to the quality of output material."
Jacob McCormick – Vibration Consultant – Vibremo
This example shows how vibration analysis techniques can allow complex problems to be resolved by making small changes. Being onsite meant we were able to track how structural differences affected the machine's performance in real time – changing what could have been months of guesswork into a highly efficient and effective one-day grinder investigation.
To find out how Vibremo can do the same for you, contact us here.
