Contributed by the experts at Bushman
A sheet lifter is a “must-have” piece of equipment for many service centers. They are used to lift and move single or multiple bundles of cut-to- length sheets of steel or aluminum. Every facility is different and therefore there is no “one size fits all” sheet lifter. They are typically configured or designed specifically for your application. This guide will walk you through the process of choosing the right sheet lifter.
Description of the loads to be handled
- Maximum weight to be lifted
- Range of lengths, from minimum to maximum
- Range of widths, from minimum to maximum
- Maximum height of the load
- How are the sheets lifted? (single sheet or plate ? single bundle, banded ? single bundle on a pallet ? multiple bundles)
Answering these questions will help to define the basic design of the sheet lifter.
Description of your duty cycle
- Light to moderate duty (a few truck loads per week)
- Heavy duty (typical metal service center)
- Severe duty (24/7 service)
For heavy to severe service, more robustness is designed into the lifter to account for metal fatigue over its operating life. Higher rated gearboxes are used. Easily accessible lubrication points are provided. Lifting bails may use replaceable pins. All these things will help a highly used lifter to work reliably for 15-20 years or more.
Design of lifting surfaces
Structural steel carrying angles are most often used for lifting banded stacks with or without pallets. It is desirable for the longest load to overhang the ends of the carrying angles by 1 to 2 feet.
If extra-long loads must occasionally be lifted, pin-on extension angles may be used.
Loads of varying lengths or loads being lifted from a conveyor will need individual lifting forks placed at fixed positions.
Sheet stacks with varying pallet lengths and lifted by the fork pockets often require adjustable sliding forks. Adjustable forks can be added, removed, or positioned to accommodate any pallet configuration.
For handling short to very long loads on a regular basis, telescoping arms and removable, adjustable forks can be provided.
Your power supply
Sheet lifters can be powered by several means, from a simple hand wheel to a severe duty electric-hydraulic system.
End-mounted or side-mounted hand wheels are commonly used. No electric power is needed for the lifter. The operator will need to climb on and off trucks to operate the sheet lifter. Be aware that on lifters over 12- to 15-ton capacity, the legs and carrying angles can become very heavy and difficult to move with a hand wheel dozens of times a day.
Hand chain wheels can be used for higher stacking. The operator can remain on the floor when operating the sheet lifter in stacks where he or she can’t reach a hand wheel.
Electric motor-driven sheet lifters are used in higher duty cycle applications or on large units with heavy carrying angles. They also offer a safety component by allowing the operator to avoid climbing on and off trucks as often. The crane must be outfitted with a power cable that is paid out to the lifter from a cable reel.
For cranes that have no power cable to plug into the lifter, a self-contained battery powered sheet lifter is offered. It is equipped with two heavy duty marine batteries in a 24VDC configuration, motor controller and operator’s pendant. A battery charger is also included for keeping the batteries charged when the lifter is not being used.
For the most severe duty applications, especially where it is necessary to lift multiple bundles, an electric-hydraulic sheet lifter is recommended. These lifters are powered by four hydraulic cylinders, with a self-contained, on-board power unit with motor, pump, valves and fluid reservoir.
Operating the sheet lifter
Often the sheet lifter is an integral part of the crane, meaning that its motor controls and operator buttons are part of the crane control system. If separate controls are needed, the manufacturer can supply the operator interface that you desire, whether it’s a hard-wired, push-button pendant station attached to the lifter or a self-contained radio remote control system so that the operator does not need to be “attached” to the lifter while operating it.
How the sheet lifter attaches to your crane
Does your crane have a single hook? Twin hooks from a single hoist? Multiple trolleys? These factors are considered during the design of your sheet lifter. A single steel bail plate on the lifter is most common. The bail opening is designed specifically for the crane hook it will be used with.
Special features and applications
There are many other features that can be designed into sheet lifters for unique applications. A few examples include:
- End hooks used to secure the ends of highly flexible, light-gage sheets
- Motorized rotation
- Automated operation
- Weighing systems
A properly applied sheet lifter should save you time and money and above all, keep your workers safe. Spend some time to discuss the above topics with an experienced manufacturer or trusted material handling partner.
Bushman Equipment, Menomonee Falls, Wis., builds custom-engineered material handling solutions for the metals industry. For more information, call 262-790-4200 or visit www.bushman.com.