Is a gasket the same as a washer? 25 July 2022

APM Hexseal is a provider of durable high-quality sealing hardware, including custom moulded gaskets and washers. In this article, APM discusses why gaskets and washers are often assumed to be the same thing and why they serve very different purposes.

Although gaskets and washers share some similarities, they serve different functions. Gaskets are used to prevent leaks around mating surfaces, whereas washers are used to distribute the load of a threaded fastener. Most washers won’t have the ability to prevent fluid or gas leakage; therefore, gaskets are the better choice for sealing applications.

The shape and size of washers are also different compared to gaskets. Most washers are small and feature a uniform circular shape to enable them to fit around bolts. Gaskets are not used with bolts, meaning they are available in a wider variety of shapes and sizes. In terms of materials, washers are almost always made of metal; whereas gaskets can be made of metals, metal alloys, rubber, and other materials.

Common types of gaskets include flange gaskets, constant seating gaskets, spiral wound gaskets and soft-cut gaskets. Gaskets are used in nearly every industry, with applications such as aerospace equipment, wind turbines, medical equipment, electronics, automotive and heavy equipment.

Common types of washers include plain washers, locking washers, spring washers and torque washers. Bonded sealing washers are used throughout many industries such as aerospace, agriculture, automotive, construction, marine, military, and mining. Their durability and effectiveness make them suitable for applications such as HVAC equipment, marine electronic, construction and industrial equipment, hydraulics and braking systems.

Custom moulded gaskets from APM

Moulded gaskets feature high durability and can withstand a wide range of operating environments. At APM Hexseal, we offer custom moulded gaskets to meet the needs of our customers. Our experienced team of designers, engineers, and manufacturing experts can work with you to develop a reliable, rugged, and high-quality gasket based on your specific application requirements.

Along with our custom moulded gaskets, we also offer a self-sealing hexagonal nut, the Seelnut®. This innovative product is made from high-quality rubber, which is moulded into the cavity of the nut itself. These nuts feature threads moulded directly into the rubber, and they provide a positive seal along the threaded section of the Seelnut® and with the contact surface. This eliminates the need for gaskets, extra surface preparation, and sealing compounds.

Washers from APM

As part of its product line, APM Hexseal also produces patented Seeloc washers, featuring moulded silicone rubber bonded to specially formed stainless steel washers. These washers work in conjunction with standard studs, screws, or bolts to create an airtight seal unlike any other. By forming an effective seal, Seeloc® Washers ensure optimal performance of electrical and mechanical equipment.  They are UL recognised, making them a perfect choice for NEMA rated applications.

Types of Seeloc® washers available include:

  • Metric Seeloc® Washers: These washers are available in all standard metric measurements to ensure an easy selection process for manufacturers around the world. They can withstand a broad range of temperatures and can resist fungus, dust, most acids and oils, ozone, and more. Also available in heavy-duty.
  • Imperial Seeloc® Washers: These washers can handle torque values at least 50% higher than our original Seeloc® Washers. They are ideal for various sealing applications, including medical equipment, chemical handling, construction equipment, and food processing. Also available in heavy-duty.

Washers and gaskets have different functions, but whichever one you need, APM Hexseal has you covered with our innovative solutions. If you have any questions about washers, gaskets, or our products, ask our experts today.
Claire Aldridge Deputy Editor t: +44 (0) 1727 743 889

Having spent a decade in the fastener industry experiencing every facet – from steel mills, fastener manufacturers, wholesalers, distributors, as well as machinery builders and plating + coating companies, Claire has developed an in-depth knowledge of all things fasteners.

Alongside visiting numerous companies, exhibitions and conferences around the world, Claire has also interviewed high profile figures – focusing on key topics impacting the sector and making sure readers stay up to date with the latest developments within the industry.