EPDM Gaskets (Water Gaskets)

William Johnston & Company Limited are the leading manufacturer of drinking water gaskets for the water utilities in the UK.

William Johnston & Company Limited have, for almost half a century, been the largest gasket manufacturers supplying the water, waste water and gas utilities and the pipeline industry in the UK. Our particular specialism, on which we have established a very robust reputation, is the supply of WRAS approved, high quality sealing products to the UK water industry and, in particular WRAS approved EPDM gaskets, which we introduced to the UK market in the 1970s.

What is an EPDM Rubber Gasket?

A gasket is a seal that is designed to prevent leakage of liquid or gas between two mating surfaces. The gasket is usually compressed so that a tight seal is made.

EPDM rubber material

EPDM (Ethylene Propylene Diene Monomer) rubber is a synthetic (man-made) elastomer (rubber) with high technical properties which is capable of making and maintaining a strong, long term seal.

The main properties of EPDM are its outstanding heat, ozone, and weather resistance. It is suitable for use against various temperature and pressure combinations coupled with strong Ozone and UV stability and resistance to degradation.
EPDM is compatible with, hot and cold water, both fresh and saline and alkalis.

It has excellent electrical insulating properties and good resistance to ketones, ordinary diluted acids, and alkalis. Its resistance to polar substances and steam is also good. It is not suitable as a seal against most oils, hydrocarbons, halogenated solvents, and concentrated acids.

WRAS approved EPDM rubber

WRAS (Water Regulations Advisory Scheme), or WRC (Water Research Council) approved EPDM is a specific grade of EPDM. Introduced into the UK by William Johnston & Company Limited in the 1970s, EPDM gasket material is today the universally approved sealing product for drinking water applications in the UK.

William Johnston and Company Limited offer WRAS approved EPDM that conforms to BS 6920 W70 and BS EN 681-1in sheet, cut gasket and strip formats. Our manufacturing processes and management system are quality assured to ISO 9001:2008 and ensures our standard practice is best practice.

We offer WRAS approved EPDM cut gaskets in a standard 3mm thickness, but other thicknesses are available. We are happy to discuss your application.

We are happy to offer advice and assistance in material selection and on sealing applications. Please contact our technical team.

Our WRAS Approved EPDM Water Industry products include

Calendared

Moulded

Extruded

We cut gaskets from calendared rolls or sheets.

Mouled parts are used as valve and pump seals amongst other applications.

Extrusions can be used as tank, chamber, door and vat lid seals amongst many other applications

These gaskets are used as low pressure pipeline seals

O rings, butterfly valve seals, metal to rubber bondings, man way seals, tank door seals

Extrusions are used as seals in WTPs, hydro schemes, etc.

Styles of WRAS Approved EPDM Water Gaskets

Full Face

Inner Bolt Circle (Ring)

Mickey Mouse (2 LUG)

USING A STEEL RAISED FACE FLANGE
THEN THE GASKET IS SEATED AS FOLLOWS

USING A STEEL RAISED FACE FLANGE
THEN THE GASKET IS SEATED AS FOLLOWS

USING A STEEL RAISED FACE FLANGE
THEN THE GASKET IS SEATED AS FOLLOWS


STEEL RAISED FACE FLANGE
AND FULL FACE GASKET


STEEL RAISED FACE FLANGE AND
INNER BOLT CIRCLE GASKET


STEEL RAISED FACE FLANGE AND
MICKEY MOUSE GASKET

 

FLAT FACE FLANGES CAN BE USED WITH THE SAME GASKET STYLES BUT PLEASE REMEMBER THAT YOU ARE COMPRESSING A LARGER SURFACE AREA OF MATERIAL THAN WITH TWO RAISED FACE FLANGES. INCREASE IN BOLT TORQUE IS REQUIRED.

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Contact William Johnston & Company Limited

For more information about our EPDM Gaskets that are available world wide, contact us on +44 (0)141 620 1666, Email us or simply complete our online Enquiry Form.

Failure to select the correct materials or products can result in damage to plant and equipment and personal injury. In specific applications, particularly where critical conditions exist, we suggest you contact us and we will consider with you the most suitable material or product. However, information supplied by William Johnston & Company Limited is intended only as technical co-operation and as a guide to the various uses of different products. No warranty is given in respect of information or recommendations by William Johnston & Company Limited which are only given for guidance and without any guarantee. The customer must satisfy themselves on the suitability of the material or product for the intended purpose. The correct fitting of products is the responsibility of the customer.

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