Fabric Expansion Joints are flexible fasteners designed to provide stress relief in duct systems by absorbing movement caused by thermal changes.
They also act as vibration isolators, shock absorbers and in some cases compensate for misalignment of adjacent ducts or equipment.
Depending on the design, they are made from a wide variety of materials, including synthetic elastomers, fabrics, insulation materials and fluoroplastics.
Designs range from single-layer structures assembled to metal frames to multi-layer structures for operation under extreme temperature or corrosion.
Layer selection is made over 5 main data: ambient temperature, ambient pressure, fluid type, outdoor conditions and movement capacity.
When the basic rules to be followed such as PTFE film laminated layers for acidic environments, wire-reinforced layers for high-cycle environments,
preformed pressure support layer for high-pressure environments, Expansion joint bolster for temperatures of 300°C and above, the operating life of the Expansion Joint is maximized.
The application of correct assembly techniques is essential for the Expansion joint to work at maximum performance.Basic assembly issues are given below;
Bonding of silicone coated outer layer fabric with RTV silicone with at least 300mm overlap at 45° angle. During this process, Silicone should never be diluted with solvents such as thinner.
Silicone application should be done homogeneously with the help of a spatula without damaging the fabric.
Fabrics containing PTFE film should be adhered at an angle of 45° by applying pressure for 1-3 minutes, depending on the layer thickness, with an iron at 400°C. It is very important that the fabric surfaces and the
PFA tape are dust-free during this process. The joint area softened after the hot ironing press process should be hardened very quickly by applying cold shock. It is very important that the joint area is not moved during this process.
It is important to bevel the edges of the connection flanges to be used during the assembly of the fabric expansion joint , otherwise the sharp edges will cause the compensator cloth to tear during operation.
It is essential to comply with the bolting rules in the application of the pressure plate. Pressure plate thickness, width, bolt size and torque values should be selected according
to these tables. Otherwise, sealing may not be achieved or tearing may occur in the Expansion joint fabric as a result of excessive pressure.
Fabric expansion joints, which are shipped as a set with a steel carcass, are shipped with the support blades assembled in order to prevent load on the fabric expansion joint and bolster and for ease of assembly.
It is important to remove these support blades after assembly. Otherwise, the compensator carcass will not be able to absorb the elongation on the line sufficiently.
A marking indicating the flow direction is made on the steel carcass or mobile type liners. It is important to comply with this marking during installation.
The router to be mounted in the opposite direction will expose the Fabric expansion joints fabric&bolster to a high amount of flow, causing rapid deformation.
External factors (ash, acid, dust, etc.) that may damage the outer layer of the Fabric expansion joints should be removed with applications similar to casing sheet.
The Fabric expansion joint project, which is shaped according to the data obtained as a result of the supervision made
by the end user or through the supervision of our experts, is confirmed by submitting it to the end user before manufacturing, and the project is finalized by applying the necessary revisions, if any.
All raw materials to be used in production are controlled within the pre-production quality control processes and included in the production.
Quality control processes are run between all the successive processes such as sizing, joining, assembly, and welding in the manufacturing process, thus minimizing the defect rate in the final product.
The resulting product is checked according to the project for the last time before shipment, and all parameters are photographed and recorded. Suitable products are stamped by the "Metrik" quality stamp and are covered by the
warranty.
It is used in thermal power plants, Iron-Steel, Cement, Aluminum etc. production industry, where there is elongation due to high temperature or vibrations due to high air flow and a maximum pressure of 0.5
Bar.
The positions of the expansion joints on the line are calculated using 3D digital analysis methods such as BIM, CFD, the basic principle of these calculations is to transfer the total elongation to the compensator equally and
accurately.
Metal expansion joints are compensating elements for movements due to thermal expansion.
They consist of one or more metal bellows with connectors at both ends and different accessories such as connecting rod, joint, depending on the application. Unnecessary vibrations in systems can seriously damage both the system and surrounding equipment.
Metal expansion joints help to isolate these vibrations as well as dampen noise and pressure fluctuations.
There are different types of metal compensators that serve different purposes such as lens type, universal joint, articulated, external pressure, pressure balanced
After determining the ambient temperature, ambient pressure, fluid type, geometric values and movement amounts, the material that provides
the highest conversion value is selected as a result of the calculation made according to the standard suitable for the Metal expansion joints type.
• EN 14917 - The European Standard specifies requirements for the design, manufacture and assembly of metal Expansion Joints for pressure applications.
• EN 13445 - The European Standard for Fireless Pressure Vessels is a standard that provides guidelines for the design, manufacture and inspection of pressure vessels.
• EN 13480 - A European Standard that specifies requirements for industrial piping systems and supports, including safety systems made of metallic materials. EN 13480 is applicable to metallic pipes above ground, ducted or underground.
• AD2000 - German code of practice for pressure vessel design and manufacture, prepared by a working group of several associations that together form the "Pressure vessel working group".
• ASME B31.1 - An American National Standard, a Power Piping Code. It specifies minimum requirements for the design, materials, fabrication, installation, testing, inspection, operation and maintenance of power piping systems.
• ASME B31.3 – The Process Piping Code, an American National Standard, provides a minimum set of rules regarding the design, materials, manufacturing, testing and inspection practices used in the construction of process piping systems.
• ASME VIII Div. I - An American National Standard that provides guidelines for the design, manufacture, and inspection of boilers and pressure vessels.
• EJMA –A design code made by the Expansion Joint Manufacturers Association, an organization founded in 1955. The standard provides guidelines for the design, manufacture and safe assembly of metallic Compensator .
Our metal expansion joints are under our guarantee for 2 (two) years after shipment.
Conditions out of warranty are listed below;
• The development of different conditions (pressure-temperature changes, etc.) other than the specified working environment conditions.
• Improper mounting techniques (See: Important issues in mounting)
• Improper storage conditions (humidity, UV light, dirt, chemicals, etc.)
Metal expansion joints by itself can absorb any axial, lateral and angular movement in pipelines, channels and vessels. Adding accessories to the metal
compensator increases the complexity while also improving the movement capabilities and extending the cycle life. Some accessories for metal expansion joints include:
The Metal expansion joint project, which is shaped according to the data obtained as a result of the supervision made by the end user or through
the supervision of our experts, is confirmed by submitting it to the end user before manufacturing, and the project is finalized by applying the necessary revisions, if any.
All raw materials to be used in production are controlled within the pre-production quality control processes and included in the production. Quality control processes are run between all
successive processes such as laser cutting, welding preparation, assembly, and welding in the manufacturing process, thus minimizing the defect rate in the final product.
The resulting product is checked according to the project for the last time before shipment, and all parameters are photographed and recorded. Suitable products are stamped by the "Metrik" quality stamp and are covered by the warranty.
Thermal power plant, Iron-Steel, Cement, Aluminum etc. It is used in production industry enterprises where there is
elongation due to high temperature or where there are vibrations due to high air flow and where there is a maximum pressure of 100 bar.
The positions of the metal expansion joints on the line are calculated using 3D digital analysis methods such as BIM, CFD, the basic principle of these calculations is to transfer the total elongation to the expansion joint equally and accurately.