Attachments for both mobile and overhead cranes increase versatility when handling awkward loads. While installation, inspection and operational practices will vary for the specific device used – some safety tips are universal. Contact the manufacturer for product specific guidelines.

Getting started

Whether the device is electric or hydraulic, it is essential that it is installed correctly. Make sure the power source coincides with the requirements of the attachment. According to the Care and Use Guide published by The Caldwell Group, Rockford, Ill., "If electrical connections are made, the power supply should be connected to the line side of the crane disconnect or to an independent circuit."

According to LIFTALL, Oakville, Ontario, "The success of load holding valves on hydraulic attachments depends on clean hydraulic oil." Load holding valves, especially on devices with quick-disconnects, are very susceptible to accumulating dirt. To avoid problems with the load holding valves, flush the hydraulic system.

Before lifting anything with a crane attachment, make sure it is working properly. Moving parts should be lubricated and operating correctly. Check the device for structural deformations, cracks in welds and loose or missing hardware. Also inspect all electrical connections for shorts and hydraulic connections for leaks in hoses or cylinders. Most importantly, if problems are identified, do not use the crane attachment until it has been properly repaired.

Like other rigging gear, crane attachments should be included in regular inspection and maintenance schedules.

Making the lift

Understanding center of gravity (CG) is the No. 1 rule of lifting. Engaging the load may be different for pallet forks than it is for tong lifters or pole grabs. But one thing is certain, if the load’s CG is not centered under the crane hook and balanced on the attachment, you risk tipping or dropping it.

Using a pallet fork example from a LIFTALL brochure, consider the relationship between the fork’s CG and the load’s CG.

"The CG of the pallet fork determines the location of the pickup trolley for handling an empty pallet fork. The pickup trolley is vertically above the pallet fork’s CG during all level empty fork manipulation." However, "the CG of the load has to be under the pickup trolley when lifting is started. The lifted load includes the pallet fork and the payload. The location for shifting the pickup trolley can be determined by knowing where the payload’s CG is located."

Related to knowing the location of the CG is knowing the weight of the load in relationship to the capacity of the attachment. According to Caldwell’s Crane Use and Care Guide, "The combined weight of the lifter and load should not exceed the rated load of the crane or hoist."

Typical lifting rules also apply to working with attachments. Use the equipment as it’s designed. Don’t load loose materials on the attachment that could fall during movement, and don’t lift loads over people. Avoid shock loading, by using slow, controlled movements and keeping the load as low as possible, without dragging it.

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