Bending heavy parts: here’s what you need to know

A part counts as heavy for bending when it weighs between 45 and 75 kg. We place heavy parts in the press brake with a lifting aid that uses four suction cups of 200 mm. Your part must therefore be at least 510 x 460 mm, with enough solid surface for the suction cups. Flanges may be no higher than 70, 150 or 230 mm, depending on part size.

At 247TailorSteel, you can have parts up to 75 kg bent. Our ordering platform Sophia® will typically warn you if your heavy part cannot be bent, and suggest possible solutions. You’ll find those in this blog as well.

When is a part heavy for bending?

A part is heavy from 45 kg. The maximum weight for bending is 75 kg. We divide parts into two groups:

• Parts under 45 kg
• Parts from 45 kg to 75 kg (= heavy)

To lift heavy parts, we use a lifting aid. This device uses suction cups to grip the part and bear all of its weight. All our operators need to do is position the part properly in the press brake.

We lift parts up to 45 kg by hand (if necessary with two people and/or the accordion bending device). The weight of a part does not limit the possible operations, as long as you draw your 3D design according to our bending guidelines.

The lifting aid enables quite a lot, but also comes with three additional guidelines:

1. Make sure your part has enough room for four suction cups.
2. Make sure the suction cups can be distributed properly over the part.
3. Make sure flanges will not collide with the lifting aid or the press brake (tools).

How much room do the suction cups need?

All four suction cups of 200 mm must fit on a solid surface of your part. If they don’t, we cannot lift your heavy part, and therefore cannot bend it.

First, parts with a lot of holes on their surface pose a problem. Suction cups cannot create a vacuum with holes underneath.

Second, parts with small surface areas have limitations. A complete blank, or even a single flange or body may be too small. Take a U-shaped part as an example: the middle section must be wide enough for one or two suction cups, because they must be able to grip the part for the final bend of the U-shape.

This brings us to the following specific guidelines:

• Always leave enough room between holes for four suction cups with a diameter of 200 mm each.
• Make sure your part has minimum dimensions of 510 x 460 mm.
• Make sure all bodies or flanges on your U-shaped product are at least 270 mm wide.
• Make sure all flanges on an L-shaped product are always 260 mm wide.

How do you distribute the suction cups properly?

Draw an imaginary cross over your product: we must be able to attach a suction cup in each of the four quadrants. Only then can the lifting aid hold your part straight.

We must always be able to position your part straight in the press brake. If not, your part will hang crooked, and our operators would have to lift it again to get it straight. We want to avoid this at all costs, as it is not ergonomically sound.

How high can a flange be on a heavy part?

The maximum flange height depends on the size of your part. Higher flanges will hit the lifting aid, the press brake or the tools. This is called a collision during bending.

Small: 510 x 460 mm to 780 x 550 mm, flange max. 70 mm

Medium: 780 x 550 mm to 1,630 x 780 mm, flange max. 150 mm

Large: from 1,630 x 780 mm, flange max. 230 mm

Which operations and shapes are not possible for heavy parts?

Edge finishing and thread tapping are not possible above 40 kg. Above 45 kg, we cannot bend closed U-channels or corrugated sheet.

• Edge finishing is not possible for products heavier than 40 kg.
• Thread tapping is not possible for products heavier than 40 kg.
• Tolerances may come out 1.5 degrees higher. Normally we can correct a deviating angle somewhat, but not with heavy parts.
• Closed U-channels and corrugated sheet are not possible above 45 kg. With closed U-channels, the suction cups often cannot get through the opening, and with corrugated sheet, they cannot achieve a vacuum.

Half-closed U-channel

Corrugated sheet

Frequently asked questions about bending heavy parts

What is the maximum weight for bending?

You can have parts up to 75 kg bent. We place parts between 45 and 75 kg in the press brake with a lifting aid, so additional guidelines apply to dimensions, holes and flange heights.

What is the minimum size of a heavy part?

A part between 45 and 75 kg must be at least 510 x 460 mm. That way, the four suction cups of the lifting aid, each 200 mm in diameter, fit on the surface.

Can I have a heavy part edge finished or tapped?

No, edge finishing and thread tapping are not possible for parts heavier than 40 kg.

Why can’t my heavy part be bent?

Usually there is not enough solid surface for the suction cups, or a flange is too high for the part size. Sophia® then shows a message with possible solutions. Read more in our blog on collisions during bending.

Questions about bending heavy parts?

If you have further questions on this topic, please feel free to contact us.