Understanding the Difference Between Gasket Types
As our friends at Dichtomatik like to say, “where there are pumps and valves, there are also gaskets.” Gaskets are critical components in fluid conveyance systems. There is a wide variety of types and materials that they can be made from. Many of the most commonly-asked questions revolve around which gaskets are right for which situations for a variety of industries including but not exclusive to: food & beverage, oil & gas, construction, agriculture, energy & power generation, and chemical processing.
While far from an inclusive list, GFS wanted to quickly touch on some of the most common gasket types and materials often asked about.
A Quick Guide to Gasket Types:
Spiral Wound Gasket
Spiral-wound gaskets utilize two sealing elements – the winding and the filler – the winding behaves like an energized spring against the flange surfaces while the filler seals the imperfections between the two surfaces. An outside ring is standard in flange applications to center the gasket between the bolts and help prevent blowout. Stainless steel inner rings are often added to prevent the windings from buckling inward potentially contaminating the media. They combine high strength with reliable sealing capacity. They function as well in low pressure and temperature applications as they do in more extreme environments, but are more expensive to produce compared to compressed fiber and elastomeric gaskets.
The simplest type of gasket, this is made from common rubber elastomers or compressed fiber and can be easily cut into virtually any size with any configuration. While often suited for low pressure environments, sheet gaskets are an ideal solution for industry standard applications like creating a reliable seal between flanges and fittings for fluid movement.
Elastomer Sheet Gasket
Most rubbers are relatively inexpensive and can be easily cut into shapes on demand. Our friends at Dichtomatik, a subsidiary of Freudenberg Sealing Technologies, maintain a variety of sheet materials to meet customer requirements – including SBR, Neoprene, EPDM, NBR, and FKM.
Aramid Fiber Sheet Gasket
Aramid fibers are a particularly strong and heat-resistant form of synthetic fiber which can have exceptional strength when tightly-woven while being low-weight. They also are highly resistant to impact, abrasion, or chemical erosion. However, they are also absorptive and have poor compression properties. A broad variety of compressed fiber sheets are available; they are versatile and inexpensive. They can generally handle maximum temperatures and pressures over 700°F and 1,000 PSI.
Elastomeric Molded Gasket
Also known as press-in place gaskets, these all-elastomer gaskets are custom-shaped and are designed for applications where there is a groove that positions the gasket between components to optimize the sealing performance in the groove. They are easy to install, require no adhesive, and are self-retaining and adaptable.
For all other applications, there are custom-made gaskets. Gallagher Fluid Seals can help advise on material, design, and other gasket questions. Our suppliers place us in a position to provide a variety of materials, including flexible graphite, PTFE, FKM, FFKM, and more.
The original article was featured on Dichtomatik’s website and can be found here.
Gallagher Fluid Seals is a partner of Dichtomatik. For more information about finding the right type of gasket, contact our engineering department today.