Rubber Washers
& Rubber GasketsMade to fit.
Built to seal.

Rubber washers and rubber gaskets sit between mating parts to seal, cushion or provide spacing. They are used in vehicles, plumbing, furniture and tools. Flat rubber washers come in different shapes, sizes and compounds to suit the assembly. Some applications need moisture resistance; others call for flexibility, controlled compression or resistance to heat, UV light, chemicals or gases. EPDM washers are one material option to discuss. As a manufacturer of rubber gaskets, we help you match the dimensions and material to the working conditions.

A rubber washer commonly sits beneath a fastener or between contacting parts. A rubber gasket seals a joint that contains liquid or gas, such as a pipe connection or housing. A rubber grommet protects a cable or tube where it passes through an opening. These parts may look similar, but choosing by function helps you specify the correct profile and material.

Rubber parts have a long history, from natural latex to today's engineered compounds. Modern rubber gaskets use both natural and synthetic rubbers. Compounding and curing allow manufacturers to adjust properties for different applications, including flexibility, hardness and resistance to the operating environment.

The elasticity of rubber washers helps them conform to mating surfaces and accommodate some movement. Rubber gaskets are used in aerospace and automotive assemblies, construction, plumbing, electrical installations, original equipment manufacturing and household appliances. Each application has its own requirements for fit, loading and material performance.

A rubber washer or gasket works as part of the joint design. It may sit beneath a bolt head or nut, or between mating surfaces, depending on whether its purpose is sealing, cushioning or spacing. Select the location, dimensions and compression for the assembly; a washer does not automatically secure every fastened joint.

When selecting a rubber washer, consider the load, compression and movement it will experience. Excessive stress can damage the part or reduce sealing performance. Useful material properties include tear resistance, abrasion resistance, density, specific gravity and hardness. Evaluate these properties under test conditions that reflect the application.

Tensile strength, tensile modulus, elongation and rebound describe different aspects of how rubber responds to a load. Compression set describes the deformation that remains after compression; a sealing gasket generally needs adequate recovery to maintain contact. For moving assemblies such as window frames, review flexibility and recovery alongside the sealing force.

Storage conditions and shelf life affect rubber gaskets before they are installed. Storage conditions and shelf life depend on the compound; keep batch information with the parts.

Temperature, sunlight, humidity and other environmental exposure can affect stored rubber washers. Natural rubber, neoprene and silicone have different storage requirements; confirm the shelf life for the selected grade rather than relying on a general material estimate.

Store rubber gaskets in a cool location away from direct sunlight, using packaging appropriate to the compound and cleanliness requirements.

Inspect rubber gaskets as part of the equipment's maintenance schedule. Signs that may call for replacement include:

• Mold or contamination that cannot be removed using an approved cleaning method.
• Loss of thickness or permanent deformation that affects the seal.
• There are visible fissures or cracks
• Loss of sealing performance.
• An unknown service history that prevents you from confirming the gasket's suitability.

Use a cleaning method approved for the rubber compound and the equipment. Check compatibility before using bleach, acids or other cleaning agents. If contamination or damage remains, replace the rubber washer or gasket.

A thick rubber washer and a thin rubber washer serve different spacing and compression needs. For a flat, round rubber washer, specify the inside diameter, outside diameter and thickness. A wide rubber ring and a rubber disk with a small center hole will behave differently under load, so include the contact area and required function.

Custom shapes range from a rectangular gasket or round gasket to a hemispherical gasket or curved saddle washer. Send a drawing showing the mating surfaces and any tube recess, holes or contours. Rubber washer sizing depends on the outside diameter, inside diameter and thickness; specify these dimensions for your assembly.

Rubber gasket properties depend on the polymer, additives and curing process. Plasticizers, curing agents, accelerators, antioxidants and pigments can affect processing, flexibility, aging and color. Specify the performance and appearance you need so the compound can be selected accordingly.

Silicone washers and neoprene washers offer different combinations of flexibility and environmental resistance. Confirm the selected compound's temperature range and compatibility with oils, solvents, acids, UV light and ozone, as relevant to your application.

Other options include Ethylene Propylene Diene Monomer (EPDM), Nitrile and Viton®. Select the compound for the required strength and resistance. For contact with potable water or food, material selection must account for the intended contact and operating conditions.

Rubber washers can be die cut from sheet material, sliced from suitable tubing or molded to shape. Injection molding fills a closed mold with compound; compression molding shapes a measured charge as the mold closes. The process depends on the dimensions, material and production quantity.

A complex rubber gasket may be individually molded or cut using a suitable process. Equipment can include extruders, lathes, presses, autoclaves and water jet cutters. Curves, ridges, asymmetric outlines and other features need to be reviewed for manufacturability and the required tolerances.

Need a custom rubber gasket? Send your drawing, material requirements and quantity so we can review the shape and production options.