The expansion joint is used in a pipe or duct for accommodating thermal expansion and contraction, vibration, and other mechanical movements. They help in protecting the equipment from damage due to movements and stress. They also help in extending the life of the system. There are many different types of expansion joints used in the piping system, such as fluoroelastomer expansion joints, elastomeric expansion joints, bellows expansion joints and more. In the present article, we have shared the features and applications of metal expansion joints and fabric expansion joints and how to choose the right expansion joint for your application.
Metal Expansion Joints
Metal expansion joints are normally constructed of either stainless steel or high alloy metals and are comprised of corrugated bellows. The following are some of the key attributes of metal expansion joints:
- High resistance to temperatures — Metal expansion joints can withstand extremely high temperatures, typically over 500 degrees Celsius (932 degrees Fahrenheit)
- Resistance to high pressure — Metal expansion joints are also designed for high levels of internal pressure, making them ideal for applications involving pipelines under pressure
- Ability to absorb significant movement — Metal expansion joints can absorb axial movement, lateral movement, and angular movement due to thermal expansion as well as alignment issues, etc.
- Minimise leakage- Metal expansion joints can be manufactured to be entirely welded together to minimise leakage associated with very high-pressure and hazardous-type fluids
- Mechanical strength and durability — When metal expansion joints are adequately engineered, designed, constructed and installed, they are resistant to fatigue and creep, as well as mechanical stress
- Reduction of vibration — metal expansion joints act as a barrier to isolate vibration generated from the use of pumps, turbines and compressors
Applications
Metal expansion joints are used in diverse industries due to their durability and flexibility. Some common applications include:
- Power Plants: Handling high-temperature steam pipelines.
- Oil & Gas: Managing pressure fluctuations in pipelines.
- HVAC Systems: Absorbing vibrations in heating and cooling systems.
Fabric Expansion Joints
Fabric expansion joints are usually made up of different types of Fabric Layers and Fabric Belts used in piping systems. These expansion joints are made fromhigh-quality, reinforced fabrics capable to withstand extreme temperatures and environmental conditions. These expansion joints provide an efficient solution for movement compensation in pipelines, especially those carrying hot gases, chemicals, etc.
- Thermal and mechanical movement absorption: These expansion joints can absorb thermal and mechanical movement from ducting systems.
- Stress reduction: These joints absorb thermal or mechanical movement from the ducting system and associated equipment/ Such stress is typically caused by temperature, pressure, or vibration changes.
- Reducing vibration: These expansion joints safeguard equipment from damage caused by shocks and vibrations. It also helps in reducing noise levels.
- Cost-Effective: Fabric expansion joints typically have a lower cost of ownership and are typically less expensive to maintain.
- Flexibility with Duct Design: Fabric expansion joints can be designed to allow for a wide range of ducting configurations (angular, lateral, axial, etc.) and movements.
- Chemical Resistant: Fabric expansion joints are not chemical resistant. However, they can be designed by the manufacturer to provide a certain level of chemical resistance. This makes them suitable for use in corrosive environments.
Applications of Fabric Expansion Joints
Fabric expansion joints are used in many applications and industries, including:
- Power Generation: Gas Turbines and HRSG Ductwork installations.
- Cement Plant: Kiln Inlet & Outlet Seal applications.
- Petrochemical and Refining: Process heaters, thermal oxidisers, reformer systems.
- Steel and Metal Production :Blast furnace gas systems, electric arc furnace off-gas ducts.
- Marine and Offshore: Ship exhaust systems, offshore platform ventilation.
- Air Pollution Control : Scrubbers, baghouses, ESP systems, wet and dry flue gas cleaning processes.
How to Choose the Right Expansion Joint: Metal Vs Fabric?
Not all expansion joints are designed equally. It is therefore important to conduct careful evaluations of operating conditions and system requirements. If you are choosing between metal and fabric bellow joints, here are some things to consider-
- Pressure condition: A metal expansion joint is ideal for a piping system operating under high pressure. One should avoid using fabric expansion joints for applications that operate at either low or near-atmospheric pressures.
- Operating temperature: When a piping system operates at extremely high temperatures, a metal expansion joint is the best choice
- Movement requirement: If large or multidirectional movement is typically present in the system, it is best to use a fabric expansion joint. If the piping system experiences controlled and predictable movement, a metal bellows is better suited for that application.
Summary
Metal and fabric expansion joints play a vital role in industrial applications. A metal expansion joint has attributes such as being able to withstand high-pressure, high-temperature, and critical fluid conditions. Fabric expansion joints are usually made up of different layers of Fabric and Fabric Belts. To choose the best expansion joint, one should evaluate factors like pressure, temperature, movement, media, and long-term reliability.
Advanced Flexible System Inc is a leading manufacturer of expansion joints engineered to meet varied industry needs. These tailored expansion joints are engineered with high precision to ensure safety, efficiency, and performance. If you are looking for tailored quotes and expert guidance, feel free to connect with our experts today.
SOURCE URL: https://blogosm.com/metal-vs-fabric-expansion-joints-understanding-features-applications-tips-for-choosing
