AXIAL EXPANSION JOINTS
Axial Expansion Joints are designed to absorb axial movements in piping systems (extension and compression in its longitudinal axial direction). The thermal expansion of a straight pipeline section between two fixed points can be absorbed by Axial Expansion Joints with a relatively compact built-in length. These Expansion Joints offer a simple and cost-efficient solution in terms of movement compensation.
Axial Expansion Joints can be equipped with all kinds of connectors, such as welding ends or welded or loose (rotatable) flanges, making them suitable for a wide range of applications.
Design range within Axial Expansion Joints
Belman Axial Expansion Joints can be designed within the following range:

DIMENSIONS:
DN 15-12.000

PRESSURE:
Up to 150 Barg (2176 psi)

TEMPERATURE:
-256°C to +1000°C

MATERIALS:
Austenitic stainless steels, High alloys, Duplex, Titanium, Hastelloy,
Incoloy, Inconel, Alloy 59

DESIGN CODES:
EN 13445, EN 13480, EN 14917
ASME VIII, div.I, ASME B31.3
ASME B31.1, EJMA
and others on request

TESTS:
Radiographic examination (X-ray), Helium leak testing, Pressure test, Air test, Dye penetrant test, Magnetic particle examination and many more
PRODUCT RANGE
Belman offers a full range of standard stainless steel Axial Expansion Joints, specifically designed to absorb movements in piping systems.
AXIAL EXPANSION JOINTS




CASE STORIES

AXIAL Expansion Joints WITH TITANIUM BELLOWS
Compared to its alternatives Titanium offers a lightweight construction for aggressive environment. Therefore these Titanium Expansion Joints are weighing in at only 6 kg.

GIANT INLINE
PRESSURE BALANCED
This 4-meter long DN 2500 Inline Pressure Balanced Expansion Joint having a balancing bellow of an amazing DN 3800.

Expansion Joints Handles High Pressure Thrust Force
Highly engineered Expansion Joint handling both high pressure, high pressure thrust force as well as absorbing axial movement for an oil Platform in Norway.
TECHNICAL DESCRIPTION
AXIAL EXPANSION JOINT DESIGNS
Belman offers customised solutions for Axial Expansion Joints that meet the specific requirements and conditions of all applications. These tailored solutions take into account factors such as temperature, pressure, material compatibility, and installation conditions. By adapting the Axial Joints to the customer’s particular needs and the industry in question, optimum performance and durability can be ensured.
Our Expansion Joints are available in various designs, sizes, and materials to meet different requirements and applications. The high quality and reliability of Belman’s Stainless Steel Expansion Joints guarantee a long service life and optimal performance of pipe systems.
AXIAL MOVEMENT
Axial movement is considered an elongation or compression of the pipe system along its longitudinal axis, meaning that in the process of absorbing the movements, the overall length of the expansion joint will either extend or compress.
Axial Expansion Joints, which are designed to absorb large movements, can contain one, two or several bellows in one unit, and larger movements can also be achieved by pre-tensioning or by installing several expansion joints on the pipe section. Depending on the nominal diameter and length, they have the ability to absorb minor lateral and angular movements and installation tolerances. However, we recommend the utilisation should be limited to their main function, otherwise its service life may be negatively impaired.
Where there is a need for absorption other than that of axial movements, we strongly recommend alternative options, and Belman will be pleased to advise on alternative solutions, such as Lateral Expansion Joints, Angular Expansion Joints or Universal Expansion Joints, ensuring the most suitable choice for your application.
Definitions
Axial movement is shown as AX and stated in mm. Compression and elongation are indicated as negative (-) and positive (+).
Example
Elongation +10 and compression -20 will be shown as: AX +10/-20 mm. Equal longitudinal movements are shown as: AX +/-20 mm (2δN).
ADVANTAGES & REQUIREMENTS
Axial Expansion Joints represents several advantages for the piping designers, but they also set some requirements for the installation. These can be seen here along with more facts about them:
ADVANTAGES
What are the advantages of using
Axial Expansion Joints?
- Simple solution for compensation of temperature fluctuations
- No change in the flow direction
- Compact and space saving solution
- Relatively low cost
REQUIREMENTS
What are the requirements for using
Axial Expansion Joints?
- Strong fix points and good guides are required
- Large movements require utilisation of several Axial Bellows
- Many fix points and guides are needed for long pipe sections
- Higher costs for fix points and guides
HOW DOES THE
AXIAL EXPANSION JOINT
WORK?
This animation showcases how axial movement is absorbed by the Axial Expansion Joint
INSTALLATION EXAMPLES

Straight
piping section with
axial expansion joints
This illustrates the importance in the use of the three fix points, as the use of two or more axial expansion joints in a piping section will create an undetermined arrangement.
The amount of movements imposed on each expansion joint is not controlled, as the pipe between the two bellows can move sideward freely in both directions depending on the friction of the pipe supports and the differences in stiffness between the bellows. It is always important to have one axial expansion joint between two fix points.

Axial pipe system expansion in a pipe system with branch connection
Typifies good practice in the use of expansion joints to absorb axial expansion in a pipe system with a branch connection. The fix point at the junction, which in this case is a tee, is designed to absorb the thrust from the expansion joint in the branch line. Note the proximity of each expansion joint to a fix point, the closeness of each first guide (G1), the spacing between the first guide (G1) and the second guide (G2) and the spacing of guides (Gn) along the remainder of each pipe section.
GET MORE INSTALLATION EXAMPLES
INFORMATION & TOOLS
Here you can download useful technical information and further materials related to Expansion Joints such as:
- Guide & Catalgoue
- Product brochures
- Look Books showing design options
- Data sheets
In Belman Academy we help you increase your knowledge on Expansion Joints and get tips and tools that will ease your work with Expansion Joints, such as:
- Technical articles and videothek
- How to guides
- Technical tutorial videos
- Trainings (video, live)
ENGINEERED EXPANSION JOINTS
LATEST PROJECTS & REFERENCES
Belman expertly engineers the optimum flexible solution to absorb movements in the pipe system while ensuring smooth operation and solutions to any operational issues for its clients. By customising and optimising the flexible solution, Belman supplies Expansion Joint solutions that provide a better TCO (total cost of ownership). See some of our latest projects and references here.






