October 31, 2013
: Do you have the right below-the-hook lifting equipment for your material handling needs? Not many metal formers ask themselves that question, but they probably should, especially if they are concerned about eliminating possible coil damage and keeping employees safe.
What determines the coil handling device you choose? It depends on the frequency that coils are being moved and if the orientation of the coil eye—the center hole—changes during the handling process.
In the steel warehouse and service center environments, coils typically are stored with the eye horizontal. The products designed for handling coils in this position are C-hook-style lifters and two-arm coil grabs.
A c-hook lifter (see Figure 1) has no moving parts, is counterweighted to hang level when empty or loaded, and requires no maintenance. The aisle width required for this lifter style is the length of the lifting arm, plus a few inches for clearance. The length of the lifting arm depends on the style of C-hook selected, but is a minimum of 80 percent of the coil width.
Styles available are standard C-hooks, recessed counterweight units, and slit coil (long-arm) units. The clearance requirement of the arm needs to be taken into consideration when you look at floor usage and potential obstructions. Optional equipment available includes urethane protection to prevent coil damage and parking stands. Custom throat and width sizes are available.
For narrow coils, smaller coil hooks can be used. With no counterweight, they provide a lightweight method for handling coils up to 5 tons. A small upending coil hook is available for easy horizontal-to-vertical coil positioning. The pivoting wedge fits under the coil, and as the crane lifts, the wedge pivots back, changing the coil’s orientation.
A two-arm coil grab (see Figure 2) can be designed in several different ways, from completely manual to fully motorized operation. The aisle width required for this type of lifter is equal to the length of the lifting foot, plus a few inches for clearance. The lifting foot width varies based on style and capacity of the lifter, but is from 8 to 13 in. on standard units. This reduced clearance requirement can increase the number of coils you can store in a designated floor space.
Manual units have steel legs that adjust along a lifting beam for specific coil sizes. The legs swing enough when empty for the foot to be properly inserted into the coil eye for lifting. The telescopic lifter legs are opened and closed by a chain wheel-driven system, allowing for infinite adjustment between minimum and maximum coil width.
A fully motorized telescopic coil grab is a fast and efficient way to move coils. Legs travel at 2.8 inches per minute and require little aisle space for lifting foot clearance. Available with a fixed or a rotating bail, the fully motorized lifter can be integrated directly into the crane controls, increasing the speed at which coils can be transported to and from storage areas and shipping bays.
The lifting foot is curved for coil protection, and high-impact plastic toe rollers help to reduce the possibility of coil damage. Built-in anticlamp sensors provide additional coil protection, and the lockout limit switch prevents the legs from inadvertently opening during a lift.
Optional equipment available for the coil grab includes urethane padding to provide additional coil protection, a built-in load scale for measuring precise coil weight, and a photo-electric sensor for simplified foot alignment.
Vertical eye coil lifters (see Figure 3) are designed for handling of vertically stacked coils and are used primarily after coils are slit to size for the manufacturing process. Several different styles are available for vertical lifters, and the type that is best for the job depends on how often, how many, and the IDs of the coils you are moving in a typical workday.
For operations in which coils have the same IDs or where only occasional lifts are performed, a standard manual vertical eye lifter is sufficient. For more frequent operations or for handling a wider range of coil IDs, a manually operated scissors-style ID lifter is a good choice. It auto-adjusts to the coil ID and then easily closes so you can quickly move on to the next lift.
The telescopic vertical eye coil lifter legs are opened and closed by a handwheel-driven system. This lifter style also can be motorized to further increase speed and efficiency.
Other types of coil handling equipment include coil upenders for changing the eye orientation from horizontal to vertical or vertical to horizontal. They also can be used to position coils onto pallets or remove them from the pallet. An optional rotational base for the upender allows you to load and unload coils from different sides.
With material costs continuing to rise, selecting the proper lifting equipment is essential. The wrong lifter can damage the load, increase waste, and potentially place employees at risk for injury.
If you are not sure which coil handling system is the best for your operation, contact an experienced manufacturer of below-the-hook lifting equipment, which can quickly evaluate your operation and determine the best equipment for your coil handling needs.
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