The risk of roll covers becoming dirty is especially high during roll
replacements. Be careful not to spill lubrication oil, grease or other dirt
on the roll or walk on it with oily or greasy shoes. Do not use dirty lifting
slings during roll replacements. The roll surface is easily damaged. Be
careful not to nick rolls with tools, etc. Also avoid high surface loads,
such as if the shell comes into contact with surrounding rolls or frames,
for example.