Thin Steel Plate lifting with magnets

With over a decade of experience designing and supplying magnetic lifting equipment for steel handling, we continue to encounter common misconceptions about magnetic lifters.

Today, lifting magnets come in a wide variety of shapes and designs, each intended for specific types of steel materials. Proper magnet selection depends on several critical factors, including:

• Steel dimensions

• Surface quality

• Material temperature

• The contact area between the steel and the magnet

One of the most frequent misconceptions involves lifting thin steel plates.

We often receive enquiries for our popular permanent magnet manual handle lifters. When we ask what they will be used for, the answer is frequently, “to handle steel plates.” That’s perfectly fine — provided the plate thickness and dimensions are suitable.

The problem arises when the steel plate is long and thin. In such cases, lifting with a single magnet positioned at the center can cause the plate edges to bend upward in an arc shape. This creates a “peeling” effect, where the plate gradually separates from the magnet during lifting — posing serious safety risks to both personnel and equipment.

For example:

A 26 ft x 8 ft steel plate with a thickness of 0.5 inches (8 m x 2.4 m x 13 mm), weighing approximately 2 tons, should not be lifted using a single 2-ton permanent magnet lifter placed at the center.

If the overhang from the magnet to the plate edge exceeds about 2000 mm (6.5 ft), the plate will bend at the edges during lifting. This bending can eventually cause the plate to peel off.

Instead of one 2000 kg lifter, use four 500 kg lifters suspended from a spreader beam. This setup reduces edge overhang and prevents bending. Ideally, the overhang should be kept within 1500 mm (5 ft) or less.

For even safer and more efficient handling of large, thin plates, electro-permanent magnet spreader beams are the ideal solution. These systems allow a single operator to control lifting remotely while ensuring proper load distribution.

That, however, is a discussion for another day.