Double Mechanical Seal

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Double Mechanical Seal Arrangement Options - A.W. Chesterton Company
Double Mechanical Seal

 

  • A double seal is designed with two primary seals, one primary seal is on process side and one is on the atmosphere side.

  • A fluid is provided between these two seals. compared to sealed fluid When it is at a lower pressure, it is called as buffer fluid; when it is at a higher pressure, it is called as barrier fluid.

  • Seal faces are arrangement in double mechanical seals: 1.Back-to-Back

  2.Tandem

  3.Face-to-Face.

  • It is mainly used to prevent pollution or saving precious liquid.

  • It is also use if media is highly hazardous, Slurry, Viscous etc

  • Seal may use water as lubricant which Neutralizes abrasives & salts


Pressurize andd Unpressurize Mechanical seal

Un-Pressurized :

  • Dual un-pressurized seal uses a buffer fluid at or near atmospheric pressure 

  • The buffer fluid pressure is significantly less than the seal chamber pressure, so any leakage occurring across the process side seal will leak into the buffer fluid
 

Pressurized :

  • Dual Pressurized Seals use a barrier fluid at a pressure 25 psi above seal chamber pressure 

  • Since the barrier fluid pressure is higher than the seal chamber pressure, any leakage occurring at the process side seal will enter the pump



Seal Configrutions

Back to Back

Face to face
        
Tandom

Each arrangement has certain advantages and disadvantages. In the end, it's advisable to consult a sealing expert who can rely on a wealth of practical knowledge and execute in accordance with your organization's requirements for dependability and environmental compliance.

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