Double Jacketed Gaskets

From www.gasketwiki.com

A jacketed or clad gasket is designed with a thin metal jacket to maintain gasket shape and to house the sealing filler. Under the clamping force of the flanges, the filler is compressed and pushes the jacket into the flange surface, creating a seal. This style of gasket has a higher service temperature range than compressed sheet material, can be made in almost any shape or configuration and can be made to any size with no real size limit. Double jacketed gaskets are the most common gasket used in heat exchanger applications. Less common is the single jacketed gasket type.

Materials

The following is a list of some common materials for the metal jacket of the gasket:

• Soft Aluminum
• Soft copper or brass
• Iron or soft steel
• MONEL
• 4% - 6% chrome
• Stainless Steel
  

The following is a list of the materials that are available for the filler:

• Graphite
• PTFE
• Ceramic
• Non-asbestos
  

Service Range

The following chart is a basic guideline for the service range of double jacketed gasket.  Actual service range factors may differ depending on the materials used for the gasket.

Filler Material	Jacket Material	Maximum Temperature	Pressure Range
Graphite, PTFE, Ceramic, Non-asbestos	Carbon Steel	572°F (300°C)	290-870 psi
	Copper	752°F (400°C)	290-870 psi
	Stainless Steel	986°F (530°C)	290-870 psi

Limitations and Replacement Options

Jacketed gaskets can only be used in an ideal flange (clean and undamaged) or it will never form a seal.  They wear out overtime due to flange movements and vibrations which eventually causes metal fatigue.  When the rounded edges of the gasket experience metal fatigue they will crack and cause a failure of the gasket and seal.

An excellent option for replacement is a Maxiprofile.  It can withstand higher pressures, temperatures and any flange movements and vibrations without showing any gasket damage.