5 min read

A compact bending head to produce new geometries

Jul 2, 2021 3:55:22 PM

In the furniture and similar sectors, where the tubes to be bent are often very long and curved into sometimes particularly complex shapes, the bending head must take up as little space as possible to leave room for the shape that the bent tube will assume.

On tube bending machines with right and left-handed bending directions, this need is much less urgent because the possibility of using one or the other bending direction solves many problems of interference between the tube and the other machine parts but this is not the case on tube bending machines with only one direction of bending. The only way to avoid the risk of interference in the latter case is to reduce the overall dimensions of the bending heads as much as possible.

Precisely to meet these requirements, the BLM GROUP developed a new compact bending head for the ELECT40, capable of executing shapes that were previously not possible with only one bending direction. It is clear that for some parts using a right or left-handed in-process tube bending machine is the only way to be able to produce the parts in a single cycle.

Discover the BLM GROUP E-TURN in-process right-hand and left-hand bending


ELECT40 all-electric tube bending with extended bending headELECT40 all-electric tube bending with extended bending head.


The two characteristics that a tube bender must have to improve part feasibility?

The fundamental aspects taken into account when designing the tube bending head to deal with geometries that were previously not feasible were:

  • reduced height of the bending head;
  • greater distance of the bending tool from the machine body.

Reducing the bending head height means that, bend after bend, the tube can move below it. Also, as shown in the figure below, the thinner the head, the more the straight part between the bends can be reduced.


Space-saving tube bending armBending a tube with ELECT40. The small size of the bending head allows the tube to occupy the space below the head.


Increasing the distance of the bending tool from the machine body reduces the chances of the tube colliding with the frame. When working with only one bending direction, the rotation of the tube in the clamp allows bends to be made in two specific directions. So it is essential to be free to orient the tube to be bent in space without collisions, even when the part has straight parts of considerable length that end up facing the machine, bend after bend.


Compact design tube bending head.Increasing the distance of the bending tool from the machine body reduces the chances of the tube colliding with the frame.


The two aspects discussed above are the main features of the ELECT40 elongated bending head, which is 35% lower and 31% longer than the standard head.

The design of the dedicated kinematic mechanisms of the head has also enabled an increase in the speed of both the bending arm (+20%) and of the clamp and the pressure die (+25%). Furthermore, a reduction in the cycle time of about 10% can be achieved on a typical part with four bends, as pictured below.

As is already the case with the standard head of the ELECT40 and the other tube bending machines in the same BLM GROUP family – ELECT52, ELECT63, ELECT80 and ELECT102 – the elongated bending head of the ELECT40 also allows manually changes of bending direction from right to left and vice versa and the use of the same compatible bending tools on all other BLM GROUP bending machines of similar size.


analisi tempi ciclo curvatura del tuboPart with four bends comparing the cycle times between ELECT40 tube bending machines with standard head and the ELECT40 tube bending machines with an extended head.


Products requiring a bending head with minimum dimensions

The design of the elongated bending head of the ELECT40 can make all the difference and allow parts to be made that were previously only possible with in-process left and right-handed tube bending machines.

This is firstly an advantage regarding greater parts feasibility, especially for manufacturers who want to approach the furniture sector, for instance, in which tubes must be bent into complicated and overly varied shapes, for manufacturers making tube parts for various types of industrial systems, for the nautical sector (handrails, ladders, etc.) and for farming machinery and equipment.


Designer chair element made with ELECT40 tube bending machine with extended bending head.Designer stool made with ELECT40 tube bending machine with extended bending head.


For manufacturers who already have an in-process right and left-handed tube bending machine, this solution can be an advantage in terms of production organization, by allowing the manufacturer to reserve the most complex parts for the in-process right and left-handed tube bending machine and send parts of medium complexity to the ELECT40 with an extended head.

A solution like this can prove to be a winner, especially for subcontractors who generally have mixed productions in terms of part complexity.

Contact us to discover more about the new ELECT40 bending head