July 2, 2024
What are gaskets? Gaskets are mechanical seals that fill the space between two mating surfaces to prevent leakage of fluids or gases. Understanding what gaskets are and how they function is essential for engineers and maintenance teams working with high-pressure systems, piping, and industrial equipment.
Gaskets create a seal by compressing between flanges or mating surfaces during assembly. This compression closes microscopic gaps and irregularities, forming a barrier that prevents leaks under pressure and temperature fluctuations. Gaskets are used across industries, including oil and gas, chemical processing, power generation, and manufacturing, where reliable sealing is critical for safety and operational efficiency.
What Are Gaskets Made Of?
Common gasket materials include:
- PTFE (Polytetrafluoroethylene): Highly resistant to chemicals and high temperatures; ideal for aggressive environments in chemical processing and pharmaceutical applications.
- Flexible Graphite: Excellent thermal stability and resilience; used in high-temperature applications such as steam systems and exhaust flanges.
- Compressed Non-Asbestos (CNA) Fibers: Safe alternative to asbestos; provides high-temperature resistance and durability in general industrial applications.
- Metallic Gaskets: Used in extreme pressure and temperature conditions; includes stainless steel, soft iron, and other alloys for high-stress sealing.
- Semi-Metallic Gaskets: Combine metal and soft filler materials (such as spiral wound gaskets) for applications requiring both resilience and conformability.
Gaskets are manufactured from materials selected based on the specific demands of each application. The choice of material depends on factors like operating temperature, pressure, chemical compatibility, and mechanical stress.
Durlon® manufactures gaskets from these materials, engineered for chemical resistance, thermal stability, and mechanical strength in demanding industrial environments.
What Are Gaskets Used For?
Gaskets serve critical sealing functions across a wide range of industries and applications.
Common applications include:
- Piping Systems: Gaskets seal flanged joints in pipelines, preventing leaks during fluid or gas transport under pressure.
- Oil and Gas Industry: Used in pipeline systems, valves, and pressure vessels to ensure leak-free transportation of crude oil, natural gas, and refined products.
- Chemical Processing Plants: Seal joints in piping and reactor systems, preventing hazardous chemical leaks and protecting worker safety.
- Power Generation Facilities: Used in boilers, turbines, and heat exchangers to maintain system integrity under high temperatures and pressures.
- Refineries and Petrochemical Plants: Seal critical connections in distillation columns, reactors, and process equipment handling volatile or corrosive materials.
Durlon® gaskets are engineered to provide reliable sealing solutions in these demanding applications, with material compositions suited for extreme conditions.
Why Are Gaskets Important?
While all gaskets provide a sealing interface, differences in material composition and construction directly influence load retention, chemical resistance, temperature tolerance, and overall service life.
Without proper sealing, leaks can lead to:
- System Failures: Loss of pressure or contamination can disrupt operations and damage equipment.
- Environmental Hazards: Leaks of hazardous fluids or gases can result in environmental contamination and regulatory violations.
- Safety Risks: In high-pressure or high-temperature systems, gasket failure can cause explosions, fires, or exposure to toxic substances.
- Increased Maintenance Costs: Frequent leaks require unplanned shutdowns, emergency repairs, and replacement parts.
In industries like chemical processing, power generation, and oil refining, gasket reliability is essential. A single gasket failure in these environments can have severe consequences, including equipment damage, production losses, and safety incidents.
Durlon® gaskets are engineered for reliability and longevity, offering industry-leading solutions including PTFE gaskets, spiral wound gaskets, metallic gaskets, and semi-metallic gaskets for diverse industrial applications.
What Precautions Should Be Followed When Using Gaskets?
Proper gasket selection, installation, and maintenance are essential to ensure reliable sealing and prevent premature failure.Material Selection Considerations
Material selection should be based on the specific operating environment, as different gasket materials involve distinct performance trade-offs related to temperature, chemical exposure, load retention, and flange conditions.With decades of experience manufacturing PTFE, graphite, and semi-metallic gaskets for critical industries, Durlon designs materials specifically to address these performance challenges under real-world operating conditions, rather than relying on one-size-fits-all solutions.
- PTFE gaskets: Offer broad chemical resistance but can exhibit creep and cold flow under sustained load, making proper compression control and bolt loading essential.
- Graphite gaskets: Perform well in high-temperature applications and maintain seal integrity under thermal cycling, though oxidation can be a limiting factor at elevated temperatures in oxygen-rich environments.
- Metallic gaskets: Rely heavily on flange surface finish, alignment, and rigidity; inadequate flange conditions are a common contributor to leakage rather than material failure.
- CNA (compressed non-asbestos) gaskets: Provide a cost-effective option for moderate service conditions but require careful evaluation of creep resistance and long-term load retention.
- Verify chemical compatibility: Ensure the gasket material is suitable for the specific fluids or gases being sealed, accounting for concentration, temperature, and exposure duration.
- Follow manufacturer specifications: Use published material properties and application guidelines to avoid mismatches that can lead to premature gasket failure.
Installation and Assembly Precautions
Follow lock-out and tag-out procedures: Ensure plant safety protocols are followed before disassembly or reassembly.- Inspect flange surfaces: Remove old gasket material, debris, and corrosion before installing a new gasket.
- Use proper torque values: Apply manufacturer-recommended torque using calibrated tools to avoid over-compression or under-tightening.
- Apply torque in a cross-pattern: Distribute load evenly across the gasket to prevent misalignment and ensure uniform compression.
- Lubricate fasteners: Apply appropriate lubrication to bolts and nuts to reduce friction and improve load distribution.
- Perform re-torquing: Re-check bolt torque after initial operation to compensate for gasket settling and bolt relaxation.
- Conduct routine inspections: Monitor gaskets for signs of leakage, discoloration, or degradation during scheduled maintenance.