What Are Spiral Wound Gaskets and How Do They Work?

If you often stay on an industrial warehouse, you have probably encountered spiral wound gaskets.  These are primarily used to create a reliable seal in between flanged joints in piping systems, which makes them a crucial component in industrial applications.  These gaskets are known for their versatility and durability, as they are used in oil, gas, petrochemical, chemical processing, and food production.

Composition and Design

  1. Outer Ring – this serves as a centering guide.  It is usually made from carbon steel that ensures the gasket fits properly within the flange.  This stabilises the gasket during installation and operation.
  2. Inner Ring – this serves to maintain the integrity of the gasket as it prevents the windings from buckling or being pulled into the piping system during operation.  Any dislodged gasket material can lead to severe operations, leaks, and equipment damages; thus, the inner ring is particularly important in high-pressure applications.
  3. Sealing Element – this is composed of metallic winding and a filler material.  If you look into it, the windings are usually made of stainless steel or monel, which provides strength and flexibility.  On the other hand, the filler material, which is often graphite, serves to enhance its sealing capability by accommodating the flange distortion and joint misalignment.

Functionality

So how do they work?  These spiral wound gaskets function by compressing between two flange faces when they are bolted together.  And as the bolts are tightened, the gasket is then compressed to allow the windings and filler material to fill in on any gaps between the flange surfaces.  This compression creates a tight seal that can prevent the escape of fluids or gases.

Another advantage of the spiral wound gasket is their ability to recover after being compressed.  That means you don’t have to worry when the flange faces expand or contract due to temperature changes, simply because the gasket can still maintain its sealing properties through this.  This feature is essential in applications where thermal cycling is very common.

Applications

Spiral wound gaskets are suitable for the following applications:

  • High-Temperature Services – the spiral wound gasket can operate effectively at temperatures exceeding 1000°F or 538°C.
  • Corrosive Fluids – spiral wound gaskets can also handle aggressive chemicals without deteriorating with the use of the right materials.
  • High-Pressure Applications – spiral wound gaskets are available in different pressure ratings, which makes them ideal for environments where high pressure is a concern.

Installation and Maintenance

The gasket should be placed in the centre of the flange and then tightened to the manufacturer’s specifications to make sure it’s properly sealed.  Don’t forget also that the outer ring is not a compression stop, so don’t excessively compress them as it may lead to a flat gasket.  This reduces its recovery capability.

A routine inspection would be of great help for your system to ensure the integrity of the gasket over time.  As there might be signs of wear or damage, or maybe leaks and visible deformation, then the gasket should be replaced.

Conclusion

Spiral wound gaskets are very important when it comes to industrial operations, as they provide reliable sealing solutions.  Their unique design allows them to effectively manage high temperatures and pressures while making sure that the flange is aligned.