What are Bonded Washers or Dowty Seals?

Bonded Washers, also known as Dowty Seals or Bonded Seals, offer a powerful solution for achieving tight, leak-free connections in various applications. They are typically used in industries such as automotive, hydraulics, and pneumatics.

These seals are comprised of a metal washer and a rubber ring, which is bonded inside the diameter. The two components work together to create a dependable and leak-free connection. Bonded Washers are primarily designed to withstand high-pressure applications, making them a popular choice in hydraulic systems.

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Properties and Materials:

The construction of Bonded Washers is simple yet effective. The metal washer, often made of steel or stainless steel, provides structural integrity, and prevents deformation under pressure. The rubber ring, typically made of nitrile rubber or other elastomeric materials, forms the sealing element. Nitrile rubber is widely used due to its excellent resistance to oil, fuel, and hydraulic fluids. However, different applications may require seals made from other elastomeric materials, such as silicone or fluorocarbon rubber, depending on the specific operational requirements.

Working Principle:

The working principle of Bonded Washers relies on a combination of compression and the elastomeric properties of the rubber ring. When the seal is tightened, the rubber ring compresses between the washer and the mating surface, creating a tight and secure connection. The rubber material provides resilience and elasticity, allowing it to adapt to slight variations in the mating surfaces, ensuring a dependable seal even under dynamic conditions.

Advantages of Bonded Washers:

Leakage Prevention: Bonded Washers offer exceptional sealing capabilities, preventing fluid leakage in high-pressure environments. Their robust design and secure connection help to maintain system integrity, reducing the risk of costly leaks and downtime.

Vibration Resistance: The rubber ring in Bonded Washers acts as a damping element, absorbing vibrations and reducing the chances of loosening or failure due to dynamic movements.

Easy Installation: Bonded Washers are simple to install, making them a time-saving solution for engineers. With just a washer and a rubber seal, they can be easily integrated into existing systems without requiring complex tools or techniques. Bonded Washers are flexible, and so can fit in a variety of devices.

Cost-Effective: These seals offer a cost-effective solution due to their durability and long service life. Their resistance to wear, tear, and degradation ensures that they can withstand demanding environments without frequent replacements, reducing maintenance costs over time.

FPE Seals stock and supply a comprehensive range of Bonded Washers that can be used to seal bolt heads and prevent leakage from hydraulic fittings or adaptors.

Can’t find what you are looking for? Get in touch with our knowledgeable team today for further advice and information about our products including a full range of hydraulic ram components.



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