What is a fabric expansion joint?
Fabric expansion joints (non-metallic) manufactured in Flexilatina of Colombia are flexible accessories designed to relieve stress and generate static sealing only in gaseous media in duct systems. They are manufactured from a wide variety of non-metallic materials, synthetic elastomers, special fabrics, PTFE, insulating materials and fluoroplastics, among the most common.
These gaskets are characterized by working with high temperatures 1200°C (2192°F), low pressures < 14.5 psi (1 bar), and only with gases (hot air, combustion gases and abrasive gases). Fabric expansion joints are widely used in Steel, Thermoelectric, Cement, Refineryrias, Petrochemical and Chemical Plants.
Applications and advantages
These expansion joints provide flexibility in ducts and are generally used in 4 applications:
- Movements caused by thermal expansion in ducts, axial, lateral and/or angular.
- Component isolation to minimize the effects of vibration or noise.
- Movement of components during process operations.
- Installation or removal of large components.
The advantages of non-metallic expansion joints are:
- They absorb large movements with minimal installation spaces.
- A single expansion joint absorbs combined movements.
- Due to the materials in which the expansion joints are manufactured, minimal force is required to move them since they have a low elastic constant.
- Their low elastic constant allows them to relieve stress in large equipment such as the exhaust of a turbine.
- Corrosion-resistant manufacturing materials.
- High-tech materials that allow use in aggressive chemical conditions.
- They do not generate noise and absorb mechanical vibrations.
- Ease of installation.
- They are relatively light and have short installation lengths.
- Minimum replacement cost; The flexible part of the expansion joint assembly can be replaced easily and economically.
- Freedom of design; Non-metallic expansion joints can be adapted to conical, transitional or irregularly shaped ducts, allowing the designer the maximum variety of options.
- Thermal insulated designs allow a flexible design with a cold layer that increases the useful life of the fabric expansion joint.
Construction of a fabric expansion joint
The flexible part of a fabric expansion joint, due to the number of layers, can be manufactured in two ways:
1) Single-layer construction
An expansion joint formed by a single layer thermoformed from high-quality elastomers and reinforcing materials or fluropolymers developed with high technology.
2) Multi-layer construction
An expansion joint formed by multiple layers, depending on the operating temperature, may have 2 or more layers.
It is characterized by having:
- Support layers: Obtain specific shapes for special configurations, protect the joint, maintain adequate insulation.
- Insulation layer: Thermally insulates the external layers of the internal part of the expansion joint.
- Thermal protection: Protects the external layers from temperature spikes due to insulation failure.
- External fabric: Protects the expansion joint from environmental conditions.