Axial expansion joints are designed to absorb axial movement (tension and compression in its longitudinal axis).

The thermal expansion of the straight pipe section between two fixed points can be absorbed by an axial expansion joint with a relatively compact built-in length.

Single axial expansion joint
Single axial expansion joint

As far as motion compensation is concerned, this provides a simple and cost-effective solution.

Axial expansion joints can be equipped with various connectors, such as welded ends or welded or loose (rotatable) flanges.

The size of the axial expansion joint

We design and manufactures various axial expansion joints.

Customized solutions

As a customized solution, the axial expansion joint can provide all sizes, all designs and all materials below DN 12.000.

Standard solution

As a standard solution, the size range of axial expansion joints is DN 25-2200.

Technical description of axial expansion joint

Axial movement

Axial movement is considered to be the extension or compression of the pipe system on its longitudinal axis, which means that in the process of absorbing movement, the total length of the expansion joint will extend or compress.

Axial expansion joints designed to absorb large movements can include one, two, or several bellows in a unit, and they can also be pre-tensioned or install multiple expansion joints on the pipe section to achieve large movements.

According to the nominal diameter and length, the axial expansion joint has the ability to absorb smaller lateral and angular deflection and installation tolerances.

However, we recommend that the scope of use be limited to the main function of the axial expansion joint, otherwise it may adversely affect the service life.

If you need absorption other than axial movement, we strongly recommend that you choose other options, and we will be happy to provide professional advice.


The axial movement is displayed as AX, expressed in mm. Compression and elongation are expressed as negative (-) and positive (+).


Elongation +10 and compression -20 will be displayed as: AX + 10 / -20 mm. The equal longitudinal movement is displayed as: AX +/- 20 mm (2δN).

Application of axial expansion joint

Axial expansion joints have the ability to compensate axial movement and have a simple and compact overall size, so they have been widely used in various applications.

Axial expansion joints are particularly common in long pipes.

Examples include exhaust systems, ventilation and flue gas systems, district heating, steam, and oil and gas pipeline systems.

Advantages and requirements

What are the benefits of using axial expansion joints?

  • Simple solution to compensate for temperature fluctuations
  • Constant flow
  • Compact, space-saving solution
  • Relatively low cost
  • What are the requirements for using axial expansion joints?
  • Need strong repair points and good guidance
  • Large movements require the use of several axial expansion joints
  • Long pipe sections require many fixing points and guides
  • Higher cost of repair points and guides

Key Reference


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