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ROLL HANDLING
One of the most frequently encountered ergonomic lifting problems is the handling of rolled materials, often weighing from sixty to several hundred pounds.

For configuring a lift to handle rolls, in addition to its weight, the outside diameter, web and core dimensions are specified. The source and destination of the roll are defined, along with roll orientation and pertinent dimensions.

In addition to specifying the appropriate model lift, and its configuration, a lifting strategy is to be defined. The strategy will depend upon the material to be handled and manipulation to be performed. Some materials such as plastic are prone to telescope if the roll is handled by its core. Others, such as foils, may disallow pressure on or contact with the outside diameter.

Typical sources include pallets, storage mandrels, shelves, carts and the floor. Typical destinations are machine mandrels or pay-off stands, storage mandrels and special carts. Rolls may be oriented with the cores up ("eye to the sky"), stacked on pallets and must be rotated 90º for assembly to a shaft or cantilevered mandrel. In some applications, a loose shaft is assembled to the core prior to lifting and a simple set of notched forks straddles the roll for moving to and lifting onto open bearings. In other applications, it may be required to rotate the roll 180º for payoff from the top or bottom.

Access to the source or destination may be limited or not have adequate crawl space for the lift's forward projecting legs. With the existence of such constraints, low profile legs may be used or no legs may be allowed. Counterbalanced lifts may be accordingly specified. In such instances countermass requirements are determined through the use of moment diagrams and actual test to satisfy stability criteria.

When heavy rolls are to be transferred to or from the lift, powered pushers and pullers may be used. Special docking fittings are attached to align the mandrels to form a continuos rod for smooth transfer.