»
Tech
Talk
5 essential facts about fabric expansion joints you need to know
Fabric expansion joints play a vital role in various industrial processes .
These joints are essential for maintaining structural integrity , preventing leaks , and accommodating thermal expansion , contraction , and vibration . Compared to metallic expansion joints , fabric expansion joints offer distinct advantages in certain scenarios , making them a preferred choice for systems that involve the movement of hot gases and air . Understanding the key aspects of fabric expansion joints is crucial for ensuring efficient operation and longevity of industrial systems . The following are five important things to know about fabric expansion joints .
About the Expert
Iberê Souza has a bachelor ’ s degree in Mechanical Engineering from the State University of Campinas ( UNICAMP ), Brazil . Born and raised in Brazil , he ’ s been living in the USA for the past ten years , where he deepened his knowledge of Quality Management Systems and ISO 9001 standards . Iberê recently transitioned to a technical market support position to develop and bring expansion joint solutions to the industry . He is currently the Expansion Joint Market Support Specialist at Teadit .
By Angelica Pajkovic , Client Specialist , and Ibere Souza , Expansion Joint Market Support Specialist – Teadit
1 – Key considerations There are several types of fabric expansion joints designed to meet specific application requirements . Users must select the style best suited to their application to mitigate the risk of asset leaks and failures . Each type of expansion joint offers distinct advantages depending on the system ’ s design , operating conditions , and movement requirements . There are therefore six primary factors to consider when choosing a fabric expansion joint .
• Operating temperature : Evaluate the temperature range of the system and choose materials that can maintain mechanical properties within the desired temperature range .
• Movement requirements ( thermal , vibration , seismic ): Assess the expected movement of the piping system and select an expansion joint capable of accommodating the required range of motions .
• Chemical and heat compatibility with process gases : Evaluate how corrosive the chemicals that will be in contact with the material are , as well as the
Teadit fabric expansion joint : Made of reinforced fiberglass fabric and coated with PTFE to be used in a pelletizing plant . temperature range of the system ; choose materials that can maintain their mechanical integrity .
• Environmental conditions ( e . g ., exposure to corrosive elements ).
• Installation : Determine the size and configuration of the ductwork / piping . Then assess whether the expansion joint needs to be assembled in the field or delivered as a single unit . It is important to consider factors such as labor costs and ease of installation .
• Compliance with industry standards and regulations .
By carefully evaluating these factors and consulting with experienced engineers or manufacturers , users can choose the most suitable fabric expansion joints to ensure reliable operation and minimize maintenance costs .
2 – Importance of materials selection Fabric expansion joints are typically constructed from specialized materials capable of withstanding high temperatures and corrosive environments . The construction of fabric expansion joints involves layers of fabric or insulation ; it is a combination of multi-layers of inorganic fabric and flueoropolymer layers externally impregnated with silicon or PTFE on their composition . The use of these materials ensures flexibility while maintaining structural integrity under challenging operating conditions . For particularly severe applications , the use of reinforced fiberglass coated in PTFE is often the most optimal choice as it has a high resistance to both heat and corrosive chemicals . The use of custom-made materials is something end users should consider when trying to tailor solutions to meet specific application requirements . A careful analysis of the system is often required before the design phase , to determine the materials of construction needed and other required components .
3 – Installation practices As fabric expansion joints use different frame types depending on the application , understanding the design elements for each joint , as well as how to install it , is of vital importance . The two distinctive categories are flanged and belt types . In the flanged configuration , the belt has a ‘ U ’ shape which allows for a small overall length ( OAL ) and a simplified metallic structure . This design reduces the initial cost of the expansion joint but can sometimes increase the maintenance cost as the belt is more difficult to replace . The belt-type configuration allows for flanged or welded connections and has the advantage of a simple belt replacement . Regardless of the frame type , several variables should be considered when installing fabric expansion joints . Here are some of the key variables to consider : External Duct Insulation : Typically seen in systems that have high temperatures , the external insulation must not overlap the belt . This could cause issues with the heat exchange between the bellows and the
24 Heat Exchanger World June 2024 www . heat-exchanger-world . com