What are Rubber Washers?

Rubber washers are small, circular or flat-shaped components made of rubber that are designed to provide a seal or cushioning between two objects. They are commonly used in a wide range of applications, including plumbing, automotive, electronics, and construction.

Key Takeaways:

  • Rubber Washers are circular components designed to provide a tight and reliable seal against the leakages of fluids, gases and air. 
  • There are 3 different types of Rubber Washers: Flat Rubber Washers, O-Rings and Bonded Rubber Washers.
  • There are many benefits to using Rubber Washers such as: Sealing Properties, Chemical and Temperature Resistance, Resilience and Cost-Effectiveness. 
  • Rubber Washers are used within a range of professional industries including: Plumbing, Automotive, Motorsport, Electronics and Construction. 
  • Rubber Washers are typically manufactured using 3 methods: CNC Digital Cutting, Hydraulic Punching and Waterjet Cutting. 
  • To correctly measure Rubber Washers you must measure the ID, OD and Thickness. 
  • Some of the most common materials used for Rubber Washers include Neoprene, Nitrile, EPDM, Butyl, Silicone and Viton. 
  • Delta Rubber Limited offer a range of standard washers available online or the facilities to design, develop and purchase bespoke washers. 

Everything you need to know about Rubber Washers:

The main purpose of rubber washers is to prevent leakage or seepage of fluids or gases between the surfaces they are placed between. They act as a barrier that seals off any openings or gaps and prevents the flow of air, water, or other fluids.

Rubber washers are preferred over other materials because of their unique properties, including their ability to conform to surfaces and their resistance to chemicals and extreme temperatures. They are also highly flexible and can be easily manipulated into the desired shape or size.

Overall, rubber washers are essential components that play a critical role in ensuring the proper functioning of a wide range of machinery and equipment. Their importance in providing a leak-free and safe environment makes them a go-to choice for many industries.

Different Types of Rubber Washers

Flat Rubber Washers

These are the most common type of rubber washers typically used for applications where a tight seal is required between two flat surfaces. They come in a variety of sizes, thicknesses and materials, typically manufactured in a circular shape. The flat design of these washers allows for a larger surface area to be covered, making them suitable for applications where the load needs to be spread. They provide a reliable seal against air, water, and other fluids and are commonly used in plumbing fixtures, electrical equipment and machinery. 


O-rings are similar to circular rubber washers but with a round cross-section, designed to fit into a groove and compress between two surfaces. This allows O-Rings to provide a seal in both radial and axial directions. O-Rings are available in a range of sizes and materials, often used for hydraulic and pneumatic systems where they provide a high degree of sealing effectiveness against pressure and fluid leaks. Additionally, O-Rings can be found in many common appliances, automotive vehicles and industrial equipment. 

Bonded Rubber Washers:

These washers are made by bonding rubber to a substrate, such as metal or plastic. The bonding process is usually achieved through vulcanization, which results in an extremely strong and durable bond. Bonded rubbed washers are used in a variety of applications where a secure seal is needed between dissimilar materials including automotive fuel systems and industrial equipment. They come in a range of shapes and sizes and are typically manufactured from materials that are resistant to heat, chemicals and other harsh conditions. 

Benefits of using Rubber Washers 

Rubber washers are often preferred over plastic or metal washers for many reasons, offering a unique set of characteristics and benefits, they are used in many industries all around the globe. But what are some of the key benefits of using rubber for washer manufacturing?

Sealing Properties: Rubber washers can provide an excellent seal due to their flexibility and the way they conform to the surface they are sealing. This can make them a more suitable choice over other materials such as metal or plastic, which will not create as tight of a seal. 

Excellent Resilience: The resilience of rubber washers means they can recover their original shape even after being compressed or stretched. This means they can provide a long-lasting, reliable seal in applications where they will be subjected to repeated cycles of compression and expansion such as in valves and pumps. 

Chemical and Temperature Resistance: Rubber washers can resist a wide range of chemicals, making them suitable for use in harsh environments where exposure to corrosives is common. Depending on the rubber material used, some rubber washers can withstand extremely high or low temperatures without losing any vital sealing properties. 

Cost-Effective: Rubber washers are almost always more cost-effective than other types of washers. This makes them a popular choice for applications where a reliable seal is required but cost is a primary consideration. 

Easy to Install: Rubber washers are easy to install and require minimal tools and equipment, making them a popular choice for many applications from DIY projects to large scale industrial work. Additionally, the flexibility of rubber washers means they can often conform to slightly uneven surfaces, making them easier to work with in certain situations. 

What are Rubber Washers used for?

Rubber washers are widely used in various industries for their sealing and cushioning capabilities including plumbing, automotive, construction, electronics and manufacturing. Let’s explore some specific applications within these sectors. 


In the plumbing industry, flat rubber washers are commonly used in plumbing fixtures and fittings such as faucets, toilets, valves and shower heads to provide a tight and leak-free seal. Additionally they can be found in pipe couplings and other connections, not only to prevent leaks, but help maintain water pressure as required. Flat plumbing rubber washers are typically manufactured from materials such as EPDM, Neoprene and Silicone rubber due to their excellent resistance to water and most chemicals, offering a long care-free life, no matter the conditions. 

Automotive & Motorsport 

The automotive and motorsport industries rely on rubber flat rubber washers and O-rings to create reliable seals for engines, transmissions and exhaust systems, eliminating the risk of fluid or gas leakages. They can also be used in vehicle suspension systems to aid in dampening vibration and reduce overall noise. High-performance elastomeric materials including Viton Fluoroelastomer and Nitrile rubber are commonly used for automotive rubber washers, offering excellent resistance to fuels and harsh chemicals. 


Flat rubber washers and O-rings are used within the electronics industry to create airtight seals in electronic enclosures, protecting components from dust, moisture and other environmental factors. Additionally, rubber washers can provide insulation and cushioning, helping to prevent damages of components through excess vibration or shock during operation. The materials favoured by the electronics industry for rubber washer manufacturing tend to be specialist grades of Silicone or EPDM that offer excellent electrical insulation properties. 


The construction industry uses flat rubber washers, O-rings and bonded rubber washers for a whole range of different applications including heating, ventilation and air conditioning (HVAC) systems to prevent leaks and ensure efficient operation. They can also be found in construction machinery and equipment, used to help absorb shock and vibration, reducing overall wear and tear. Rubber washers manufactured for the construction industry must be durable and able to withstand heavy usage, therefore Neoprene, EPDM and Nitrile are often selected. 


Rubber washers find numerous applications within the manufacturing industry, especially within production machinery and equipment where both flat rubber washers and bonded rubber washers are used in conjunction with bolts, nuts and screws to provide a reliable seal, preventing the loosening of fastenings due to excessive vibration. These rubber washers are typically manufactured from reliable materials including Neoprene, EPDM and Nitrile. Additionally, flat rubber washers and O-rings are commonly found in conveyor systems used in food processing manufacturing facilities, where FDA approved materials such as silicone rubber are vital.

How are Rubber Washers manufactured?

Rubber Washers are manufactured using various techniques and different machinery including CNC Digital Cutting, Hydraulic Punching and Waterjet Cutting. Among these methods, CNC digital cutting is the most common and versatile manufacturing technique for rubber washers. Here is an overview of each method:

CNC Digital Cutting 

CNC (Computer Numerical Control) digital cutting is a precise and efficient manufacturing method for rubber washers. It involves using computer controlled cutting machines equipped with specialised tools to accurately shape and cut rubber materials. CNC digital cutting offers several benefits for rubber washer production including: 

  • Cost Effectiveness – CNC Digital Cutting allows for high automation and precision, reducing material wastage and overall production costs. The CAD software allows you to embed each washer shape side by side, allowing for maximum utilisation of the rubber material, minimising waste and optimising cost effectiveness. 
  • Shorter Lead Times – The automated nature of CNC Digital Cutting enables quick setup and production, resulting in shorter lead times for manufacturing washers. This is particularly beneficial for meeting tight production schedules or urgent orders. 
  • Accuracy in Production – CNC machines are capable of achieving high levels of accuracy and repeatability in cutting rubber materials. Working to extremely high tolerances, CNC Cutting ensures consistent dimensions and shapes for the rubber washers, meeting the required specifications for a project. 

Hydraulic Punching 

Hydraulic Punching is an older and more traditional manufacturing method commonly used for smaller production runs of rubber washers. It involves using a hydraulic press equipped with specially designed cutters to create the desired dimensions and holes in rubber materials. Whilst it might be suitable for small designs or low volume production, hydraulic punching is not as precise or efficient as CNC digital cutting. 

Waterjet Cutting 

Waterjet Cutting is a specialist manufacturing process used for cutting densers, harder or thicker rubber materials that cannot be easily cut with accuracy through the standard CNC cutting process. It utilises a high-pressure jet of water mixed with abrasive particles to precisely cut through the rubber material. Waterjet cutting offers the advantage of being able to handle more challenging materials but is typically reserved for specific applications where other cutting methods are not suitable due to the increased costs of using a waterjet machine. 

In rubber washer manufacturing, CNC digital cutting stands out as a preferred technique due to its cost-effectiveness, reduced lead times and accuracy in production. However, hydraulic punching and waterjet cutting can be utilised when specific project requirements call for their unique capabilities.

Measuring rubber washers accurately is essential to ensure the right fit and proper functionality in your applications. Here’s a step-by-step guide on how to measure your rubber washers:

  1. Inner Diameter (ID) – This refers to the measurement of the hole or opening in the centre of the washers. To measure the ID of a rubber washer, use a calliper or measuring tape. Place the jaws of the calliper or measuring tape inside the hole and measure the widest part. Take note of the measurement in millimetres (mm) for optimum accuracy. It’s important to know that the ID of rubber washers is also referred to as the ‘M’ measurement, for example a 4mm internal diameter would be known as M4, whilst a 12mm internal diameter would be M12. 
  2. Outside Diameter (OD) – This refers to the measurement across the widest part of the washer, including the edges. Again to measure the OD of a rubber washer use your callipers or measuring tape. Place the jaws of the calliper or measuring tape on opposite sides of the washer, ensuring they rest just on the outer edges. Take note of the measurement in millimetres (mm). 
  3. Thickness This refers to measurement from one flat surface of the washer to the other, indicating how thick the rubber washer is. We suggest only using callipers when trying to determine the thickness of your rubber washers for accuracy, placing jaws on each side of the washer and slowly compressing, before taking note of the measurement in millimetres (mm). The thickness of your rubber washer will be the thickness of the rubber material you require. 

How to choose the right material for your Rubber Washers

When choosing the right material for your rubber washers, it’s essential to consider the specific requirements of your applications. Each material offers unique characteristics, strengths and limitations. Now we will explore the rubber materials most commonly used for rubber washer manufacturing, along with their benefits and suitable applications: 

Neoprene Rubber Washers 

Neoprene is a versatile material, offering a cost-effective rubber washer solution that still holds important weathering, ozone and moderate chemical resistance. The material is one of our most popular rubbers used for washer manufacturing and  also offers good physical properties including flexibility, durability and outstanding abrasion resistance.  

Neoprene rubber washers are commonly used in plumbing fixtures, electrical equipment and machinery where the materials benefits such as resistance to oil, moderate temperature variations and good compression set means they can provide a tight and reliable seal for almost any general purpose rubber washer application. 

Nitrile Rubber Washers

Nitrile, or NBR offers exceptional oil resistance, good physical properties and resistance to an expansive range of chemicals. Nitrile rubber washers are highly valued for their ability to resist almost any oil, fuel, solvent or hydraulic fluid, making them suitable for sealing applications in the automotive, oil and gas or industrial sectors. 

Nitrile rubber washers also hold excellent abrasion resistance, anti-vibration properties and the ability to resist extreme temperatures. We recommend using nitrile rubber washers for any applications where risk of corrosion from fuels or harsh fluids is possible. To learn more about Nitrile rubber, its properties, applications and benefits check out our recent comprehensive blog post on the elastomer. 

EPDM (Ethylene Propylene Diene Monomer) Rubber Washers 

EPDM is renowned for its exceptional weathering, water, and ozone resistance. EPDM rubber also offers electrical insulation properties and the ability to retain its flexibility even at high or low temperatures, making EPDM rubber washers suitable for outdoor applications in roofing, plumbing or electrical enclosures. 

EPDM rubber washers offer highly reliable sealing against moisture, weather and exposure from UV radiation. They exhibit good chemical resistance, electrical insulation properties and long-lasting performance in outdoor environments. We almost always recommend EPDM rubber for rubber washers destined for usage outside. 

Butyl Rubber Washers 

Butyl rubber is known for its low gas permeability, making it an excellent choice for rubber washers used in air retention applications. The material also holds exceptional resistance to weathering, ozone, chemicals, gas and moisture and commonly used for sealing applications against air, nitrogen and other gases. 

Butyl rubber washers provide reliable sealing, vibration dampening and air retention properties, meaning they find a place in a range of professional industries including the automotive sector, construction and manufacturing where their long list of benefits are crucial.

Silicone Rubber Washers 

Silicone rubber is one of the most versatile elastomers on the market, boasting a wide operating temperature range, excellent flexibility and resistance to chemicals, UV radiation and ozone. Silicone rubber holds the ability to perform well within almost any harsh environment and therefore silicone rubber washers are called upon for many projects. 

Some of the most common applications of Silicone rubber washers include electrical insulation, food processing equipment and for medical seals where the materials high-temperature resistance, electrical insulation and hygienic properties are required. We recently released an informative blog post covering the properties, applications and benefits of Silicone rubber, click here to learn more about the material. 

Viton Rubber Washers 

Viton rubber is a world renowned high-performance material used for rubber washer manufacturing due to its exceptional resistance to extreme temperatures, chemicals and fluids. Additionally Viton rubber offers a low compression set, high tensile strength and good abrasion resistance, making it suitable for demanding industry applications. 

Viton rubber washers are valued for applications requiring resistance to aggressive fuels, oils, solvents, acids or high temperatures, where the elastomer outperforms other materials. Viton is commonly used in industries such as aerospace, automotive and the chemical industry due to its unique properties and benefits, offering durability and longevity of life no matter the application. For everything you need to know about Viton rubber including its properties, applications, benefits and a comparison against other rubbers, check out our recent blog post on the material. 

Buy Rubber Washers online:

Now you’ve learnt what rubber washers are, the types of rubber washers available, manufacturing techniques and common materials used for rubber washer manufacturing, its time to order rubber washers for your project. 

If you are using rubber washers for general purpose applications, we suggest opting for our cost-effective Neoprene rubber washers. Manufactured from a high-quality black 70° shore A Neoprene rubber and available in a range of sizes including M4, M5, M6, M8, M10, M12, M16 and M20 and variations in thickness and outside diameters to suit almost any project. You can purchase neoprene rubber washers in quantities from 25 to 1000 units by clicking here, available with next working day delivery and always highly competitive prices. 

For rubber gaskets manufactured from any other material such as Nitrile, EPDM, Butyl, Silicone or Viton rubber, why not take advantage of our online washer builder? You can design, develop and securely purchase bespoke rubber washers in 4 simple steps. Head to our sister company Gaskets Direct, select ‘circular gasket/washer’ from our pre existing templates, fill out the customisable options including outside diameter and internal diameter, choose your rubber washer material, thickness and quantity required before receiving a quotation straight to your inbox with a link to buy securely online.

Alternatively, feel free to contact us to receive a rubber washer quotation today. Simply provide us with your rubber washer dimensions, material and quantity required and we will endeavour to provide a cost-effective quotation in response. For large volume orders or continued supply, we offer generous wholesale discount rates and strive to build long term partnerships with our clients. 

Frequently Asked Questions (FAQ’s)

Do Rubber Washers stop leaks?

Stopping leaks is one of the most common applications of rubber washers, the water resistance properties of rubber means they are often used for this purpose. 

Are Rubber Washers waterproof?

Washers manufactured from rubber are always waterproof and the go-to choice for leak prevention. 

What does a Rubber Washer do?

Rubber washers help to prevent leaks, protect surfaces or even dampen vibration for many different applications within various industries. 

Are Rubber Washers the same as Rubber Gaskets?

Although they share similarities, rubber washers tend to be circular components with a hole in the middle. Whereas rubber gaskets come in many different shapes and sizes. 

Are Nylon Washers or Rubber Washers better?

Rubber is softer and more flexible than Nylon, this means that it will conform to surfaces better and provide a more reliable seal. We would recommend rubber washers over nylon for most projects. 

Are Silicone Washers or Rubber Washers better?

The choice between silicone washers and standard rubber washers depends solely upon the application. If your washers are going to be used with extreme high or low temperatures or around food processing equipment, we suggest opting for silicone washers. For most other applications, rubber washers will be sufficient.