Mantek (Manufacturing) Ltd


Mantek hold a comprehensive range of O-ring sizes and materials. Our standard O-ring materials are Nitrile, Viton®, PTFE, Silicone, EPDM and Neoprene. We also hold some stocks of the following: Carboxylated Nitrile, Hydrogenated Nitrile, Fluorosilicone, Peroxide cured EPDM, Polyurethane and coloured Nitrile and Viton®.

Popular sizes and grades of Kalrez® O-rings are usually stocked in Europe and will therefore be available within a few days - contact our sales office for more information.

Whilst for other O-ring materials such as Aflas®, Natural rubber, Polyisoprene rubber, Styrene Butadiene rubber and Butyl rubber we can, depending on the required quantity, offer short manufacturing lead-times or even the possibilty of locating stock.

To find out about more about how to choose the correct O-ring material, standard available sizes and suggested gland/housing dimensions please call us or visit our website.

Teflon Encapsulated Seals

Encapsulated seals were primarily designed to solve the growing problems of sealing corrosive fluids in industry. This development provided designers and engineers with a seal that combined the chemical resistance of Teflon® with the resilience of rubber.

A seamless Teflon® (FEP or PFA) jacket surrounds an elastomer core providing the chemical inertness, whilst the memory in the elastomer core energises the seal.

Encapsulated seals are available with two types of Teflon® jacket - FEP which is standard, and PFA for more demanding applications.

The energising core is available in Viton®, Silicone or EPDM. Viton® is offered as the standard because of its superior compression set. For low-temperature applications, or where lower closure forces are required either a solid Silicone or hollow Silicone core is specified.

For a more detailed description of Teflon® Encapsulated seals please call us or visit our website.

Teflon Encapsulated Seals

ASTRA O-ring Seal

The ASTRA seal is comprised Stainless steel 302 flat wound ribbon spring encapsulated in either a Teflon® FEP or PFA jacket to form an O-ring.

These specialised seals are particularly suited for use at extreme low temperatures (-250°C). At these very low temperatures other seal materials become brittle and usually this is followed by seal failure.

Download our product information sheet from our website.

ASTRA O-ring Seal

Inflatable seals

An inflatable seal can be compared to a bicycle inner tube, which when inflated expands (radially outwards) to fill a void which is contained within the wheel rim (housing) and a tyre (jacket). Once air is let out of the inner tube the tyre runs flat.

When designing an inflatable seal the same mechanical and pneumatic processes will need to be considered during the design. Most inflatable seal solutions will end up using a ’standard’ profile, however for some applications a totally bespoke design may be necessary.

Every inflatable seal will therefore require a technical design to be carried out, whilst the delivered solution may well be based on a seal profile that has been used and proven many times. The success or failure will depend on all design constraints being known at the start of the design.

  • they only seal when you want them to
  • once pressure is removed the seals retract to their original shape
  • they do not suffer from premature loss of compression set
  • they can be designed to fill larger gaps than conventional seals
  • they will effect a seal or clamp force even when the two faces are non-concentric or misaligned.

There are many industries that will find an inflatable seal a useful sealing solution. The following industries already utilise inflatable seals: Pharmaceutical, Medical, Food Processing, Transportation, Marine, Chemical processing, Paper processing and Aerospace.

Premium O-ring Cords

Mantek’s premium quality O-ring cords are extruded from low compression set compounds. Low compression set is one of the most desirable physical properties when selecting a material for seals. Seal materials with a high compression set can fail after only a few hours of use. Our cords were developed for their low compression set and suitability for the method of manufacture used. The manufacturing system employs a ‘closed loop’ control system where laser micrometers feed-back to a computer which controls the extruder.

For detailed information about Mantek’s Premium O-ring cords, visit our website and down load a copy of our Premium O-ring Cords brochure.

SJV O-rings

One of our most popular products is the Scarf cut and hot vulcanised joined cord ring (’SJV O-ring’).

Our factory has developed a very successful method of producing O-rings from extruded cord to a very high technical standard.

The most important factors affecting the quality of this product is the mechanical characteristics and dimensional accuracy of the extruded cord stock. Care has been taken to select only compounds with a very low compression set, this is critical for producing high quality vulcanised joins.

Cord tolerances are tightly controlled and continuously checked using laser micrometers (tolerances are usually tighter than ISO 3302-1 E1).

SJV O-rings
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