Tube bending is an essential technique in many industries, from the automotive sector to aviation. Despite state-of-the-art machines and processes, errors can still occur during the bending process, leading to wasted material, production delays or poor quality. At Tinsel, your experts for tube bending machines, we will show you the common problems that occur during tube bending and how you can solve them effectively.

1. Buckling of the pipe

Problem:

A common problem with pipe bending is buckling or creasing on the inside of the bend. This occurs particularly with thin-walled pipes that are not sufficiently supported.

Solution:

Use mandrel bending, where a mandrel is inserted into the pipe to support it from the inside. The mandrel prevents the pipe from deforming or wrinkling on the inside. In addition, the bending parameters should be set carefully to avoid excessive stress.

2. Ovalization of the pipe

Problem:

Another common problem is the ovalization of the tube when the cross-section is changed from a round to an oval shape during bending. This can compromise the structural integrity of the tube, especially in applications that require high precision.

Solution:

Use a machine that supports the pipe at several points simultaneously to minimize the deformation of the cross-section. In addition, the use of bending shoes or dies with a suitable shape can help to reduce ovalization.

3. Creasing on the inner wall

Problem:

When bending pipes, especially with tight radii, creases can form on the inside of the bend. This can not only affect the aesthetics, but also restrict the function of the pipe, especially in the case of pipes or pipes with flow requirements.

Solution:

Rely on the mandrel bending technique and, if necessary, use a die with a narrow bending radius to avoid the formation of creases. You should also ensure that the material is guided evenly and slowly around the bending template to minimize tension.

4. Cracks and fractures in the material

Problem:

Cracks or fractures can occur during bending, particularly with brittle or hard materials such as titanium or high-strength steel. This often occurs if the material is not prepared correctly or is overstretched.

Solution:

Avoid excessive pressure and check the material parameters carefully. With hard materials, it may be useful to heat the pipe before bending (hot bending) to increase elasticity and minimize the risk of cracks.

5. Inaccurate bends

Problem:

If the bends are not precise enough, this can lead to fitting problems during final assembly. Especially in the automotive industry or in piping systems, precision is crucial to ensure tightness and functionality.

Solution:

Use a CNC-controlled tube bending machine that offers high accuracy and repeatability. CNC machines ensure that even complex bends are performed accurately and consistently. You should also regularly check that the machine is correctly calibrated.

6. Springback of the pipe

Problem:

After bending, the pipe can spring back slightly due to stresses in the material, which means that the desired bending angle is not exactly maintained. This springback often occurs with materials such as steel or copper.

Solution:

To compensate for springback, you need to slightly overbend the bending angle. Modern CNC machines have software that can calculate the degree of springback of the material and compensate accordingly. Alternatively, manual adjustments should be made based on experience.

7. Irregular changes in wall thickness

Problem:

During bending, the thickness of the pipe wall may change. On the outside of the bend, the wall becomes thinner, while it becomes thicker on the inside. This can lead to problems, especially in pressurized pipes.

Solution:

This change can be minimized by using machines with controlled tensile and compressive forces. Mandrel bending also offers a solution here, as it better supports the internal structure of the pipe and prevents the wall thickness from collapsing.

8. Poor surface quality

Problem:

After bending, scratches, grooves or irregularities can occur on the surface of the pipe, which not only impair the visual appearance, but also have a negative impact on the function and service life of the pipe.

Solution:

Use high-quality bending tools and make sure that the machines are well maintained and free of dirt particles that could damage the material. Smooth and polished bending templates and dies also help to improve the surface quality.

9. Wrong choice of machine

Problem:

An often overlooked problem is choosing the wrong machine for the material to be bent or the bending process. A machine that is not designed for the desired material type or specific requirements can lead to a variety of problems.

Solution:

Make sure that the tube bending machine is matched to the materials and bending techniques used in your production. At Tinsel, we offer a wide range of machines for all applications and advise you individually to find the best solution for your requirements.

10. High material costs due to waste

Problem:

Incorrectly bent pipes often lead to rejects, which in turn increases material costs and impairs production efficiency.

Solution:

By using CNC-controlled machines and choosing the right bending technology, you can significantly reduce waste. In addition, your machines should be regularly maintained and calibrated for precise work.

Conclusion: Avoid mistakes and increase productivity

Errors in tube bending can significantly affect the efficiency and quality of your production. However, by using the right machines and techniques, you can easily avoid these problems. At Tinsel, we not only offer you high-quality machines, but also comprehensive advice to ensure that your bending processes run smoothly and error-free. Our experts will help you find the ideal solution for your specific requirements and minimize errors during tube bending.