Spiral Wound Gaskets

What are Spiral Wound Gaskets?

Flanges are pieces of hardware that join portions of pipelines, tubes, and other materials transporting equipment. They are frequently joined with fasteners such as bolts and are a good way to make secure connections, but they are not always fluid-tight without gaskets.

A spiral wound gasket that has been properly selected and placed can endure high temperatures and pressures, preventing leaks for the life of the product.

Components of Spiral Wound Gaskets

Three components make up a spiral coiled gasket:

• The outermost ring

  The outermost ring, made of carbon steel, is also known as the centering ring or guide ring. The outer ring is used to center a gasket when it's inserted into a bolted flange joint.

• The inner ring

  The inner ring is critical for the gasket because it prevents the windings inside the pipe from buckling. Parts of a gasket get sucked into the pipe when it buckles. Pieces of the gasket will then normally flow through the pipeline until they catch on anything. They frequently become entangled in rotating machinery, like a pump. The resulting mess is referred to as a "bird's nest." Inner rings assist in avoiding this issue.

• Sealing component

  As the name implies, the sealing element produces a seal that prevents leaks. Windings and filler material are both considered sealing elements. A flexible graphite filler material suitable for high temperatures is used in most spiral wound gaskets in oil and gas refineries. Gaskets with flexible graphite filling are also more tolerant of flange deformation and joint misalignment. Another frequent filler material is polytetrafluoroethylene (PTFE); however, PTFE is not suitable for high-temperature applications. Meanwhile, stainless steel and Monel are the most common winding materials in refineries.

How Spiral Wound Gaskets are Made

Spiral wound gaskets come in various shapes and sizes, but they all work on the same principle. In some models, numerous plies of metal and several plies of soft filler are wound around each other, providing both the strength of the metal and the flexibility and sealing properties of the filler.

Other types have only metal plies in a circular pattern coupled to a soft filler outer ring. Alternating metal and filler rings can be used in other patterns, but they are less frequent. Every spiral wound gasket must be meticulously matched to the contours of the pipes, hoses, or other equipment it will seal.

The composition of the gasket must also not interfere with the operation of the equipment. Most gaskets are made of stainless steel, which has a low reactivity to transferred substances.

The filler materials, which range from graphite to polytetrafluoroethylene, must be selected with greater care based on their flexibility, durability, chemical reactivity, and operating longevity.

Types of Spiral Wound Gaskets

The types of spiral wound gaskets include:

Style CG

In this style, a spiral wound gasket comprises a sealing element and an outer metal ring. By limiting overcompression, the outer ring ensures optimal sealing performance. The ring also aids in accurately placing the gasket on the mating flange faces.

Style CG gaskets are used on flanged connectors with raised and flat faces. They're commonly used in mild to moderate service environments.

Style CGI

In addition to the outer metal ring, this spiral wound gasket type has an inner metal ring. The CGI-style gasket's inner metal ring limits the sealing element's internal and external diameters.

It acts as an additional compression stop and prevents the sealing portion from buckling within. It also establishes a physical barrier between the sealing element and the process stream, protecting it from heat and media and preventing erosion.

Spiral wound gaskets of the Style CGI type indicate moderate to severe service conditions on raised and flat-faced flanged connectors.

Applications of Spiral Wound Gaskets

Flange connectors can be formed randomly or be stressed. A flexible gasketing solution that maintains seal integrity is required in these situations. Engineers developed spiral wound gaskets to address this difficulty; spiral wound gaskets combine the structural strength of metals with the sealing qualities of softer filler materials such as elastomers and graphite.

Spiral wound gaskets can be used in gas pipelines, tubing, and other networks of transmissive channels. They can also be found in pumps, valves, thermal exchangers, and various other components and control devices for gas and liquid transportation systems.

Choosing the Right Spiral Wound Gasket Supplier

To ensure you have the most productive outcome when purchasing spiral wound gaskets from a spiral wound gasket supplier, it is important to compare several companies using our directory of spiral wound gasket suppliers. Each spiral wound gasket supplier has a business profile page highlighting their areas of experience and capabilities, along with a contact form to directly communicate with the supplier for more information or request a quote. Review each spiral wound gasket business website using our patented website previewer to quickly learn what each company specializes in. Then, use our simple RFQ form to contact multiple spiral wound gasket companies with the same form.