Seals & Gaskets

Verified by Mel Sykes, Industrial Supply Chain Specialist - April 2026

Specification	Details
Types	O-rings, oil seals, mechanical seals, gaskets, V-rings, bonded seals
Materials	Nitrile (NBR), Viton (FKM), EPDM, silicone, PTFE, neoprene
Standards	BS ISO 3601 (O-rings), ISO 6194 (rotary shaft seals), BS 7531 (gaskets)
Temperature range	-60C to +300C depending on material

## What are Seals & Gaskets? Seals & Gaskets prevent leaks and maintain pressure integrity between mechanical parts by filling gaps and blocking fluid passage. They're critical components in machinery across various industries. ### Types of Seals & Gaskets O-rings, oil seals, mechanical seals, gaskets, V-rings, and bonded seals are common types used to ensure proper sealing under different conditions. - **O-Rings**: Donut-shaped rings made from elastomers that fit into grooves to create a seal. - **Oil Seals**: Used in rotating equipment like pumps and motors to prevent oil leakage while allowing rotation. - **Mechanical Seals**: Complex assemblies often used in high-pressure environments with multiple sealing elements. - **Gaskets**: Flat, compressible material placed between two surfaces to provide static seals. - **V-Rings**: Wedge-shaped seals that create a tight seal against rotating shafts under compression. - **Bonded Seals**: Consist of rubber or elastomer bonded to metal rings for use in high-pressure applications. ### Materials and Specifications Seal materials include Nitrile (NBR), Viton (FKM), EPDM, silicone, PTFE, and neoprene. Each material has specific properties suited for different environments: - **Nitrile**: Resistant to oils, fuels, and hydraulic fluids but not suitable for high temperatures. - **Viton**: Highly resistant to chemicals and extreme temperatures up to 204°C (399°F). - **EPDM**: Excellent resistance to water, ozone, and UV light; ideal for automotive and plumbing applications. - **Silicone**: Flexible over a wide temperature range (-60°C to +200°C) but less resistant to oils and fuels. - **PTFE**: Ideal for high-temperature environments due to its chemical inertness and low friction coefficient. - **Neoprene**: Durable against petroleum-based products, but not suitable for temperatures below -35°C (-31°F). Standards such as BS ISO 3601 cover O-rings, ISO 6194 outlines rotary shaft seals, and BS 7531 specifies gaskets. These standards ensure consistency in dimensions, performance criteria, and testing protocols. ### How to Choose the Right Seals & Gaskets Selecting the right seal or gasket involves considering factors like operating environment, temperature range, pressure levels, media compatibility, and required lifespan: - **Operating Environment**: Identify potential contaminants such as dust, moisture, chemicals, and oils. - **Temperature Range**: Ensure the chosen material can withstand both minimum and maximum temperatures without degradation. - **Pressure Levels**: Determine if a dynamic or static seal is needed based on whether the application involves moving parts. - **Media Compatibility**: Select materials that resist corrosion from fluids and gases in contact with the seal. - **Lifespan Requirements**: Consider how often seals need to be replaced, aiming for minimal downtime. ### UK Suppliers MLC lists verified suppliers registered with Companies House, providing reliable options like CBM (British Seals), BIAFD (Rubber Products Association), BTMA (Bearing and Sealing Technology Manufacturers' Association), and BPMA (British Pump Manufacturers' Association). ### Common Applications Seals & Gaskets are used in numerous industries for diverse applications: - **Automotive**: Engine oil seals, transmission seals, fuel system gaskets. - **Aerospace**: High-pressure hydraulic systems, airframe sealing, turbine engine components. - **Manufacturing**: Pneumatic and hydraulic cylinders, valves, pipe connections. - **Construction**: Plumbing joints, HVAC ductwork, roofing membranes. Understanding these applications helps in choosing the right materials and designs for optimal performance.