Plate heat exchangers (PHEs) play a critical role in thermal processing for many industries, but it is the gaskets that seal and direct flow while supporting long-term reliability and efficiency. Gasket failure can lead to cross-contamination, unforeseen downtime and loss of pressure—all of which disrupt system performance and production.
Gasket selection and maintenance are high-priority with increasing regulatory standards from the Food and Drug Administration (FDA), rigorous clean-in-place (CIP) protocols and harsh operational environments such as high temperature or chemical exposure. This article explores the functional role of PHE gaskets, compares materials, outlines maintenance strategies and highlights emerging technologies that support extended service life and reduced maintenance.
Function of Gaskets in Plate Heat Exchangers
Gaskets serve a dual purpose: They seal around the ports and plate perimeter to prevent cross-contamination, and they direct process fluids through designated flow channels. Open and closed sections in the gasket design allow process fluid to enter assigned flow paths while preventing passage into others. This ensures that hot and cold fluids pass through alternate plates, pressure drop is maintained and turbulent flow improves thermal exchange.
Gasket Materials & Design Considerations
Gasket materials and design must align with the system’s operating environment, industry regulations and performance requirements. Proper selection of gasket material and design is critical for maintaining safety, equipment longevity and operational integrity. Key factors to consider include temperature range, system pressure, cleaning protocols (CIP/sanitization in place [SIP]) and chemical compatibility.
Common materials include:
- Nitrile rubber (NBR): Often used in HVAC, oil cooling and some industrial water systems, NBR offers high oil resistance and durability at moderate temperatures. It is not recommended for systems using steam, strong acids, ozone or harsh chemical solutions.
- Ethylene propylene diene monomer (EPDM): EPMD is commonly used in pharmaceutical, food and beverage and some chemical processing systems due to its excellent resistance to water, steam, mild acids and alkalis. It is not compatible with petroleum-based fluids.
- Fluoroelastomer (FKM): Suitable for chemical processing, heavy industry, oil and gas and other high-temperature applications, FKM offers high thermal stability and chemical resistance but can become brittle at lower temperatures. It is not recommended for cold service conditions.
- Silicone: Commonly used in sensitive food and pharmaceutical applications because of its high-temperature stability and flexibility at lower temperatures, silicone is not suited for chemical and mechanical industries due to limited mechanical strength and chemical resistance.
- Polytetrafluoroethylene (PTFE): Useful in highly corrosive environments where non-reactive contact is vital, PTFE is chemically inert and nonstick. However, it lacks elasticity and often requires mechanical support or specialized housings for effective sealing.
PHE gasket designs have been modernized for both performance and serviceability. The two primary attachment methods are glued and clip-on gaskets.
Glued gaskets are bonded to the plate using adhesives such as synthetic rubber or chemical-resistant glue until they are properly placed together. Glued gaskets are typically more reliable at keeping the plate in place until the plate pack is placed in the heat exchanger frame. When the heat exchangers are assembled, it is very important they follow the OEM instructions for the gap setting within the heat exchanger to provide the proper compression for the plate pack. The proper gap setting ensures the heat exchangers work to their potential. Glued gaskets offer strong sealing integrity, durability in harsh conditions and long-term stability. However, they can be harder to remove and replace, increasing maintenance time.
Clip-on gaskets use molded tabs, grooves or locking features to stay in place without adhesives. They offer quick installation and removal, simplifying maintenance. They are less reliable than glued gaskets for long-term durability, particularly in high-pressure or high-vibration systems.
When selecting gaskets for PHEs, engineers should consider operating temperature, chemical compatibility, pressure cycling, cleaning protocols (CIP/SIP) and industry-specific hygiene standards.
Maintenance & Life Cycle Management
Gasket maintenance can be undervalued, but failure leads to cross-contamination, hazards and production downtime. PHE gaskets operate under extreme pressure, high temperatures and aggressive chemicals. Over time, these stressors degrade gasket materials, compromising seal integrity and system performance.
Implementing a structured inspection routine and replacement schedule will extend gasket service life and reduce shutdowns.
Signs of concern for gaskets are:
- Cracking or brittleness: Visible cracks and breaks, particularly corners and bends, indicate heat aging, UV exposure or chemical damage. The gasket has likely lost its elasticity and sealing effectiveness.
- Swelling or softening: The gasket appears bloated, warped or soft to the touch, indicating chemical incompatibility.
- Compression set or flattening: The gasket is permanently flattened and does not spring up after being compressed, indicating overcompression, lack of maintenance or incorrect material.
- Leakage or weeping: Visible moisture, stains and fluid buildup around gasket joints and frames indicate a loss of elasticity or improper seating due to wear and tear and misalignment.
- Hardening or discoloration: The gasket is unusually rigid or shows notable color changes, indicating chemical degradation or exposure to extreme temperatures.
- Gasket pull-out or misalignment: The gasket is displaced or not seated flush against the plate, indicating repetitive assembly/disassembly, poor installation or failure of adhesive.
To maintain gaskets:
- Establish a regular inspection schedule
- Use a calibrated torque wrench when assembling to maintain consistent pressure
- Use cleaning agents compatible with gasket materials
- Store extra gaskets in a cool, dry and clean environment
- Replace or schedule a replacement promptly at the first signs of damage
Always source replacement gaskets from the OEM. Generic or aftermarket gaskets may appear cost-effective initially, but alternatives often lack traceability, precise tolerances and verified quality control. OEM gaskets are engineered to specifically match plate geometry and exact material standards while complying with regulatory standards.
Looking Forward: The Future of Plate Heat Exchanger Gaskets
Advances in elastomer engineering have also expanded chemical compatibility and extended gasket lifespans. New formulations resist aggressive solvents and high heat while maintaining flexibility under pressure. On the sustainability front, manufacturers are exploring bio-based rubber, nonhalogenated compounds and recyclable materials to reduce environmental impact.
These innovations are driving a shift toward longer-lasting, more traceable and more sustainable gasket solutions—critical upgrades for industries facing stricter compliance and tighter production margins.
Staying Ahead of the Curve
As regulatory pressures increase and production margins narrow, maintaining plate heat exchanger (PHE) systems—and the gaskets that support them—has never been more critical. The process starts with selecting the right gasket material based on operating conditions, chemical exposure and industry-specific standards.
Gasket reliability depends on proper maintenance, timely replacement and sourcing components from the OEM. OEM gaskets are engineered for precise fit and long-term compatibility, helping reduce downtime and extend equipment life.
As PHE technology evolves, gaskets must meet growing demands for chemical resistance, regulatory compliance and sustainability. Whether designing a new system or maintaining an existing one, system performance depends heavily on gasket integrity.
Consult with qualified experts, review all system conditions and evaluate gasket performance regularly to ensure safety, efficiency and return on investment. A proactive approach today prevents costly failures tomorrow—and positions an operation for long-term success.
