Common Sanitary Gasket Failures & How to Prevent Them

3 min read
Common Sanitary Gasket Failures & How to Prevent Them

Common Sanitary Gasket Failures & How to Prevent Them

Sanitary gaskets are small components with a major responsibility: they provide the primary seal in a Tri-Clamp connection. When a gasket fails, the entire process is at risk. Leaks, contamination, pressure loss, and unplanned downtime often trace back to gasket degradation caused by chemical attack, heat, mechanical stress, or improper installation.

This guide covers the most common gasket failure modes in hygienic processing systems and how to prevent them through proper material selection, installation, and maintenance.

1. Chemical Attack & Swelling

Chemical exposure is one of the leading causes of gasket failure. Caustics, acids, sanitizers, solvents, and oxidizing chemicals can break down incompatible materials.

Signs of chemical attack:

  • Soft, swollen, or tacky gasket surface
  • Loss of elasticity or shape deformation
  • Gasket “growing” and no longer fitting properly
  • Surface pitting or blistering

Common causes:

  • Using Buna-N in caustic or acidic environments
  • Exposing EPDM to oils or solvents
  • High-concentration or improperly diluted CIP chemicals
  • Incompatible sanitizers (e.g., peracetic acid on certain elastomers)

How to prevent it:

  • Match gasket material to chemistry: PTFE or FKM for aggressive cleaners
  • Verify CIP chemical compatibility tables
  • Monitor detergent concentration and pH
  • Use PTFE when chemical exposure is variable or unknown

2. Thermal Degradation (Heat Damage)

Repeated exposure to heat—especially in SIP cycles—can harden or embrittle elastomeric gaskets.

Signs of heat damage:

  • Cracking, chalking, or brittleness
  • Loss of elasticity or hardening
  • Visible flattening of the sealing surface

Common causes:

  • SIP steam sterilization cycles (240°F–280°F)
  • Running elastomers above their rated temperature
  • Thermal cycling causing expansion and contraction

How to prevent it:

  • Use PTFE or FKM for routine SIP exposure
  • Confirm max temperature ratings for each material
  • Avoid sustained high-heat exposure with Buna-N or EPDM
  • Maintain consistent clamp torque to prevent extrusion during expansion

3. Compression Set

Compression set occurs when a gasket loses its ability to rebound after being compressed. Over time, this leads to leaks even if the gasket appears intact.

Signs of compression set:

  • Gasket remains flattened after clamp removal
  • Loss of sealing force around the entire circumference
  • Recurrent leaks despite proper clamp torque

Common causes:

  • Overtightening clamps
  • Extended exposure to heat
  • Repeated assembly/disassembly cycles
  • Using low-compression elastomers in high-pressure systems

How to prevent it:

  • Use torque-controlled clamps in critical applications
  • Select EPDM or FKM for better compression-set resistance
  • Avoid PTFE in high-vibration applications where elasticity is needed
  • Establish routine replacement intervals

4. Extrusion & Blowout

Extrusion happens when part of the gasket squeezes out between ferrules. Blowout is a more severe failure — the gasket is forced out entirely under pressure.

Signs of extrusion:

  • Gasket material bulging outside the clamp
  • Product leaking at high or low pressure
  • Partial gasket displacement during CIP

Common causes:

  • Overtightening clamps
  • Misaligned ferrules or worn sealing faces
  • Excessive system pressure
  • Using soft elastomers at high temperature

How to prevent it:

  • Ensure ferrules are aligned and undamaged
  • Use high-pressure clamps when required
  • Choose PTFE or FKM for high-heat, high-pressure lines
  • Verify clamp torque is within spec

5. Mechanical Damage from Installation

Improper installation can damage even perfectly compatible gaskets.

Signs of installation damage:

  • Pinched or torn gasket edges
  • Indented surfaces from misalignment
  • Uneven sealing due to debris or improper seating

Common causes:

  • Misaligned ferrules
  • Installing a dry gasket without lubrication in certain setups
  • Trapped debris during assembly
  • Using a worn or damaged clamp

How to prevent it:

  • Clean ferrules thoroughly before assembly
  • Center the gasket evenly between ferrules
  • Inspect clamps for wear or deformation
  • Follow a consistent torqueing method

Which Materials Resist Failure Best?

Failure Mode Best Material Options
Chemical Attack PTFE or Viton/FKM
High Heat / SIP Cycles PTFE or Viton/FKM
Compression Set EPDM or Viton/FKM
Extrusion (High Pressure) PTFE (best), FKM

No single material is perfect for every application, which is why selecting the right gasket is one of the most important decisions in hygienic processing.

Need Help Preventing Gasket Failures?

PNW Sanitary stocks Buna-N, EPDM, PTFE, and Viton/FKM gaskets for Tri-Clamp systems. Our team can help you identify failure causes, select the right material, and improve sealing performance across your process line.

Contact us anytime for gasket recommendations or troubleshooting assistance.