ELASTOMER BELLOWS MECHANICAL SEALS
Elastomer bellows seals
OVERVIEW
What are elastomer bellows seals?
Elastomer bellows seals are flexible mechanical seals with moulded sealing components made from rubber-like materials that provide a leak-proof, self-aligning seal around rotating shafts.
An elastomer bellows mechanical seal is a popular solution for general-purpose pumping equipment, offering cost-effective reliability without the need for secondary components like springs.
These elastomer bellows seals support a wide variety of industrial applications, with material options that enable compatibility across a broad range of process fluids.
Explore our elastomer bellows seal solutions
Type 2100
Fully Unitized, Heavy-duty Elastomer Bellows Shaft Seal
Designed for demanding applications, the Type 2100 mechanical seal is a compact, unitized...
Type 2106
Fully Unitized Elastomer Bellows Shaft Seal
The Type 2106 mechanical seal is a compact, unitized, single-spring elastomer bellows seal that not only offers durability...
Type 502
Unitized Elastomer Bellows Seal
The Type 502 mechanical seal is one of the best-performing elastomeric bellows seals available...
Type 6
Low-pressure Elastomer Bellows Unitized Seal Head for Small-diameter Pumps
This compact, unitized, single-spring, elastomer bellows mechanical seal is designed for use in small centrifugal water pumps...
Type 1/1A
Full Convolution Industrial-duty Elastomer Bellows Shaft Seal
With its proven track record of exceptional performance, the Type 1 elastomer bellows seal is widely recognized as the industry's workhorse...
Type 2
Multi-purpose Non-pusher Elastomer Bellows Seal
The Type 2 mechanical seal is available in single, double and balanced arrangements...
Type 21
General-duty Elastomer Bellows Shaft Seal
Our general-purpose Type 21 mechanical seal has become the industry standard for OEM designers...
Type 5611/5611Q/5611L
Universal Cartridge Seal Family — Single Cartridge Elastomer Bellows Seal
As the first truly universal cartridge seal, the modular family concept...
IN MORE DETAIL
What are elastomer bellows seals used for?
Elastomer bellows mechanical seals are widely used in high-volume rotating equipment, in industries such as water and wastewater systems, chemical processing, mining and mineral slurry pumps, and oil and gas.
John Crane elastomer bellows seals provide axial flexibility and dynamic secondary sealing without the need for a moving O-ring, while the integrally driven bellows transmits torque directly to the seal faces. This helps maintain stable seal performance under shaft movement, thermal growth and variable operating conditions.
With John Crane elastomer bellows seals, cartridge options, installation and replacement are quick, reducing labour and downtime in mission-critical environments.
John Crane Performance Plus™
John Crane Performance Plus™ is our modular service framework, supported by the largest mechanical seal service network, with over 200 manufacturing, sales and service centres globally. That means we are where you need us, when you need us – empowering people, plant and performance.
Common questions
When to use elastomer bellows seals?
Use elastomer bellows seals in low-pressure, non-corrosive applications where easy installation, self-alignment and cost-effective sealing are required. They are ideal for general-purpose pumps, wastewater systems and high-volume industrial equipment.
How long do elastomer bellows seals last?
Elastomer bellows typically last several years, depending on operating conditions such as temperature, pressure and chemical exposure. John Crane designs its elastomer bellows using high-performance materials to maximise durability, helping ensure long service life, reliable performance and reduced unplanned maintenance in appropriately controlled applications.
What is the best material for bellows seals?
The best elastomer depends on the application. Nitrile resists oils and water; EPDM handles hot water and chemicals; and Viton® performs well with high temperatures and hydrocarbons. John Crane selects materials based on testing and application requirements to ensure optimal sealing performance and longevity.
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