Jul 3, 2018
Due to the weight and overall size of calender rolls, reel spools, and paper rolls, handling accidents can cause serious injury or death to personnel, and costly repairs to the roll, spool or other equipment. However, handling accidents can be avoided if basic safety rules are followed.
Only trained personnel should remove or install calender rolls or parent rolls. It is best to use the same personnel for all roll or reel handling tasks, especially for calender roll removal procedures.
Inspect all load bearing and lifting devices before handling rolls. Breakdown of the lifting devices (sling or crane hook) could result in dropping the roll.
Never lift rolls over anyone's head. Do not proceed if anyone is beneath the crane or anywhere a falling roll or tools could present a hazard. Keep all personnel away from the calender area during transfers.
|CAUTION: Never lift rolls or equipment over anyone's head. Never walk under suspended loads. Hooks or slings can slip and could cause injury or death.|
Make sure to position the crane in exact alignment with the roll, both length and width, to prevent contact with equipment during lifts or lowering.
Do not lift suspended loads any higher than necessary. Whenever possible, transport the load only a few inches above the floor. If this is not possible, hoist the load high enough to clear all obstacles.
Use the slower crane lifting speed when lifting or carrying roll equipment. The faster speed should be reserved for raising and lowering empty crane hooks.
Pay attention to the task! Operator inattention when transporting suspended loads can cause accidents.
Do not hand guide rolls. See exception in "Calender Roll Handling Guidelines".
Do not place the roll on an uneven floor without blocks. This could result in runaway rolls.
Follow these additional guidelines when removing/installing calender rolls:
Follow recommended roll removal instructions.
Depending on the equipment provided, refer to the OEM manual maintenance instructions and safety during maintenance instructions.
Do not remove any fasteners for mounting rolls and their related equipment until the lifting equipment is fully engaged. For example, bolts which attach bearing housings to the calender (levers, slides, frame, etc.).
Do not remove the lifting equipment until the roll and equipment are properly stored or bolted in place.
Secure unbalanced bearing housings to the lift slings or hooks to prevent rapid rotation of the housing which could cause injury.
Be aware of roll weights to avoid excessive loading which could lead to damage to or breaking of the lifting devices (sling or crane hook). This could result in dropping the roll. Refer to roll dimension data in the original roll documentation.
When necessary, use multiple cranes.
Prepare the roll properly. Improper rigging could allow the roll to slip out of the sling or yoke.
Before attaching lifting equipment to any roll, verify that the stack is open. In spindle stacks, the adapter for the roll or equipment being removed must be resting on its slide and the slide must be resting on its spindle nut. In lever stacks, the pivot arms must be setting down on the stops and there must be gaps between the rolls.
Keep all personnel away from the calender during roll changes, especially off all platforms, until the roll is properly positioned. Proper position depends upon the calender design. For instance:
When using special crane tools (such as cigarette holders), avoid lifting the tools near the roll to avoid snagging the rolls on the stand. Always check the lift path and possible obstructions.
Lift rolls at the roll journal whenever possible. Lifting the roll by the body may damage the roll surface. Make sure to use the appropriate lifting tools.
When using a wheeled cart to transport rolls, it is a good practice to remove the roll from the stack and place it directly onto the cart. Make sure that the cart is designed to distribute the weight of the roll properly over the floor area. The cart should be long enough to contain the entire roll and distribute the roll’s weight.
When installing rolls, make sure to:
|WARNING: Do not re-torque bolted-on journals on any iron rolls. These bolts are torqued to factory specifications with the roll at a specified temperature. Torquing these bolts while the roll is cold could cause them to fail when the roll is heated.|
Return all tools and auxiliary equipment to their proper storage places when the roll change has been completed.
For more information on improving safety at your calender, contact your Valmet representative.