The Lord of the O-Ring: One O-Ring to seal them all

Exploded image of fitting showing internal components

With our natural resources more precious than ever before, it is crucial to ensure that our plumbing systems prevent costly water leaks wherever possible. Now, hardly anyone will be as vocal to champion great plumbing inventions as the fellowship of RWC’s JG Speedfit team. And next to the trusty push-fit, we’d have to select the ever-reliable O-Ring as one of the simplest, yet most common components used in the professional plumbing industry. Found in most fluid power systems, the O-Ring – or toric joint – is one of the most integral components for any piping system. It’s highly likely you’ve used large numbers of O-Rings throughout your career to date, but how much do you really know about them?

In this blog post, we reveal some of the things you probably don’t know about the O-Ring.

1. O-Rings are not just for plumbing

O-Rings play an important role in push-fit fittings in the plumbing industry. They’re the part of the pipe connection that is used to make a seal, preventing water to leak from the inside and reducing the risk of costly water wastage. O-Rings have low insertion forces and allow the pipework and fitting to rotate. This simple seal guarantees the smooth performance of the plumbing system and resists both the internal and external pressures faced.

However, O-Rings are not just for plumbing. Did you know that O-Rings are also used in a number of other industries? This simple, yet functional invention, is often used for sealing elements, or for energising elements for hydraulic slippers, seals, and wipers. The high-performance properties of the O-Ring have made it common in almost every field of industry including aerospace, automotive, and general engineering.

2. O-Ring failure is quite rare post installation

O-Rings are designed to enhance the leak-proof properties of a system and practically never fail to do so after installation, provided it has been carried out correctly. Most recorded O-Ring failures are a consequence of poor installation or a lack of knowledge about the product. Installers following best practice guidance will know to avoid sharp edged pipes, as they can cut or displace the O-Ring during installation. Leaks can also be caused by inserting a poorly scored pipe into the fitting, while scoring damage can act as a miniature trench underneath the O-Ring, creating recesses where water ingress occurs.

The best way to reduce the likelihood of a pre-installation O-Ring failure is by specifying a high-quality O-Ring product at the start of a job. Ensuring that any O-Rings you carry in your toolbox are tested to industry standards will boost your confidence that the end user can rely on a system that won’t cause costly leaks through unexpected pipe bursts.

To further mitigate the risk from scored pipes, JG Speedfit developed a Superseal Insert which has its own O-Ring that gives an additional seal within the internal bore/port, meaning it is always in perfect condition.

O-Ring used in a cartridge system

3. You can calculate the performance of an O-Ring yourself

One way to understand the strength and durability of an O-Ring is by looking at the internal pressures they have been designed to work under. For example, EPDM rubber O-Rings used by JG Speedfit are rated at 12 bar when used with cold water. As a comparison, this is about four or five times the air pressure of a typical car tyre, which is around two bar. Whilst you would never exceed your recommended tyre pressure by a factor of five, JG Speedfit’s internal laboratory tests have found that our O-Rings can be subjected to fluid pressure tests at 60 bar without failure.

4. There are several organisations that can advise on O-Ring quality

WRAS, together with ASTM, ISO, and DIN, are widely-respected regulators of O-Rings. These products can achieve WRAS Material Approval as long as the material used to manufacture them does not contaminate the water flowing through them, therefore satisfying the requirement of regulations and bylaws. Additionally, you can be sure of product reliability if you specify an O-Ring from a manufacturer that is based in the UK, such as JG Speedfit.

5. An O-Ring was used as part of Thomas Edison’s light bulb patent

Ok, so technically it wasn’t an O-Ring as we know them today, but a round rubber ring was used as part of Thomas Edison’s light bulb patent back in 1882, 14 years before the O-Ring was patented. It was while developing automotive brakes when inventor Niels Christensen perfected the O-Ring design though, with the product being sold en masse to the military during World War II for use in aircraft.

Delivering benefits to a multitude of industries, the humble O-Ring has a lot in common with the push-fit concept: a seemingly simple component that is as important to plumbing today, as it is to many other sectors. Now, that truly is precious.

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Richard Bateman

Product Marketing Manager Plumbing and Heating

About the author

A highly experienced and passionate professional, I have over 15 years' experience as a commercial and domestic plumber and hold NVQ Level 3 qualifications from City and Guilds

Since joining RWC in 2015, I began as a technical engineer, utilising my extensive knowledge to provide exceptional support. Currently, I am thrilled to be working with the marketing department as a Product Marketing Manager. 

This role allows me to combine my technical background with a keen eye for market trends, ensuring that RWC's products meet the evolving needs of the industry. With my wealth of experience and commitment to excellence, I am proud to serve as a spokesperson for RWC, sharing our innovative solutions and contributing to the growth of the plumbing and heating sector.