|Calculation and Design Standards
||Design and calculation standards are well-established and widely recognized, often following industry standards such as EJMA (Expansion Joint Manufacturers Association), ASME (American Society of Mechanical Engineers) and European Standards.
||Design and calculation standards are available but may not be as standardized or universally accepted as those for metal expansion joints. Engineers may need to rely on manufacturer-specific data and guidelines, which can vary between suppliers. The Fluid Sealing Association handbook is a compilation of standards of construction and a guide for rubber non-metallic expansion joints.
||Suitable for high-temperature applications, often exceeding 1200 °C (2190 °F).
||Limited temperature resistance, typically up to 150 °C (300 °F) or lower.
||Excellent pressure resistance, suitable for high-pressure systems.
||Moderate pressure resistance, suitable for low to moderate-pressure systems.
||Good resistance to corrosion, especially when made from stainless steel and other corrosion resistance metals.
||Good corrosion resistance properties but is vulnerable to corrosion in aggressive environments.
||Can be designed for specific chemical resistance but may require additional coatings or linings or special materials.
||Can be chemically resistant depending on the rubber material but may degrade over time in aggressive chemicals. PTFE lining is possible.
||Offers good fire resistance.
||Varies based on rubber material; may not provide fire resistance.
|Resistance to Abrasion
||Resistant to abrasion, suitable for applications with abrasive/erosive media using right materials and/or linings.
||Vulnerable to abrasion and may wear out faster in abrasive environments.
||Can be customized for specific chemical compatibility but may require additional measures.
||Limited chemical compatibility compared to metals; may deteriorate in the presence of certain chemicals.
|UV Resistance and Sunlight Exposure
||Resistant to UV radiation and sunlight exposure. Suitable for outdoor applications.
||Susceptible to UV radiation and sunlight exposure, may require protective measures.
||Unaffected by ozone exposure. Ozone does not pose a significant threat.
||Vulnerable to ozone exposure, requiring ozone-resistant rubber in certain environments.
||Resistant to heat aging, maintaining structural integrity at high temperatures.
||Vulnerable to heat aging, which can lead to hardening and deterioration over time.
|Movement Absorption Capacity
||Good for absorbing axial, lateral, and angular movements.
||Excellent for absorbing axial, lateral and angular movements.
||Higher spring rates than rubber expansion joints. Provides limited flexibility compared to rubber, which may restrict movement in some cases.
||Lower spring rates. Highly flexible and capable of accommodating a wide range of movements.
|Noise and Vibration Control
||Limited noise and vibration control capabilities.
||Excellent noise and vibration damping characteristics.
||Limited shock absorption capabilities.
||Excellent shock absorption properties, making them suitable for systems with frequent pressure surges or shocks.
||Long service life, often exceeding 20 years or more with proper maintenance.
||Relatively shorter service life, typically 5-10 years.
||Low maintenance required, occasional inspection and tightening of bolts.
||May require more frequent inspections and replacement due to wear and tear.
||Typically more expensive upfront but cost-effective over the long term due to durability.
||Lower initial cost but may incur higher replacement and maintenance costs.
||Often requires skilled labor for welding and proper alignment.
||Easier and faster installation, suitable for various connection methods.
||Heavier than rubber expansion joints, which can affect structural support requirements.
||Lighter weight, which may reduce structural support needs.
|Cleanliness and Hygiene
||Suitable for applications where cleanliness and hygiene are required selecting the right materials, cleaning procedures, specific linings, etc.
||Ideal for applications in the food, pharmaceutical and sanitary industries due to their smooth, non-porous surfaces always selecting the right internal elastomer or lining.
|Cost of customization
||Custom designs and materials can increase costs significantly.
||Easily customizable with various rubber compounds, reducing customization costs.
|Accessibility for site inspection
||May be challenging to inspect due to their complexity in some cases.
||Easier to inspect without the need for disassembly in most cases.
|Compatibility with ancillary equipment
||May require additional engineering for compatibility with ancillary equipment.
||Typically more straightforward to integrate with other system components.
|Welding and Fabrication
||Require skill welding during fabrication and generally during installation.
||Typically, no welding or fabrication skills are needed for fabrication and installation.
||Metals are good electrical conductors, so metal expansion joints can conduct electricity. This property can be an advantage or disadvantage depending on the application.
||Rubber is an insulator and does not conduct electricity, making rubber expansion joints suitable for applications where electrical conductivity is a concern.
|Handling and Transport
||Metal expansion joints are heavier and may require special handling and transportation considerations.
||Rubber expansion joints are lighter and easier to handle and transport.