How to ensure Rolls are undamaged and are safe to use?
How to ensure Rolls are undamaged and are safe to use?
There are several methods used to ensure that rolls are not damaged and are still safe to use:
- Easiest method: Clearance gauge (Seamer Setup Camera) – A visual tool placed in the seamer that images the rolls against the chuck to verify their position and assist in their adjustment. This tool also allows the operator to see major defects in the roll and chuck profile, like broken off corners of the chuck, worn out profiles on the rolls, etc and even defects in the bearings that the rolls are mounted on. The benefit of this technique is that it does not require taking the roll out of the seamer for inspection.
Above – A visual report of heads 8-11 of the seamer’s 1st operation rolls in the Clearance Gauge. You can clearly see that the roll profile on head 11 is worn beyond use.
- Most accurate method: Profile scanners – computerized roll profile scanners work by scanning the profile of the roll and automatically comparing this profile to a diagram standard (the same roll when it was brand new or a CAD file). Any wear will be measured and compared to the standard. These tools are the most accurate way to detect roll problems, but require the operator to take the rolls out of the seamer in order to scan them. These are basically computerized, automated optical comparators.
- Visually checking the Titanium Nitride (TiN) coating – Seamer tooling is often coated in gold-colored TiN layer between 5-10 microns thick (0.0002″-0.0004″) . When this protective layer is depleted, the roll will quickly begins to wear. This layer depletes unevenly and it often goes unnoticed, so this method is not recommended.
Above – A TiN coated seaming roll with the TiN layer depleted