FEATURE
Issue: 

Connecting the 
past to the future

Since starting out as a zinc die casting company more than 50 years ago, John Guest has diversified into many areas and is now very active in the blown fibre push-fit connectors market. 
Tim Gillett reports

When John Guest himself invented the Speedfit push-fit fittings in the 1970s, he had already been running an engineering company for more than a decade – but he can scarcely have imagined that his invention would one day be used in state-of-the-art telecommunications systems.

This family owned and managed company was founded in 1961 in West Drayton, Middlesex, UK, serving industrial applications including pneumatics and zinc die casting. Some 54 years later – and still having its headquarters and manufacturing based in West Drayton, the company has expanded on a global scale and diversified to serve industries including plumbing and heating, automotive, drinks dispense and pure water, compressed air services – and, more recently, fibre optics.

Gary Hall, the company’s UK divisional director for special products, explains that the key to being successful in these markets – and a major reason behind the firm’s overall success – was the invention and development of the original push-fit connector, a simple but critical collet-gripping mechanism that allowed John Guest to penetrate such a wide variety of markets. Founded upon a highly disciplined, quality driven, world-class UK manufacturing facility, the company has retained in-house design and tooling capabilities; an increasingly unique principle in an age of outsourcing.

Though the guidance of light by refraction, the principle that makes fibre optics possible, was first demonstrated in the middle of the 19th century, it was not really until the 1980s that the use of fibre for communications became widespread, John Guest was proud to be involved at the forefront of blown fibre system development in the UK, working in conjunction with what was then British Telecom, the UK’s national telecommunications provider.

Hall told Fibre Systems: ‘Fibre optic communication systems needed to be industrialised, evolving from lab to real-world use – and John Guest became involved in this development because of our recognised expertise by British Telecom in push-fit technology. John Guest developed the first push-fit connectors specifically for fibre optics, for use with micro-duct systems utilising blown fibre installation methods. It was very much a bespoke product because there was no standard at the time – John Guest established the ‘standard’. ‘These specialised connectors, which needed to accommodate and protect delicate fibre bundles, were based upon our traditional Speedfit design, with certain enhancements for fibre-optic capability,’ said Hall. The fittings still use the original collet concept that was first patented in the 1970s; the collet gripping mechanism remains the critical component and has stood the test of time, with billions of John Guest push-fit connectors in use in a wide variety of applications being the company’s strongest endorsement.

Of course, in fibre optics, accuracy and reliability are all-important.

Hall continued: ‘Our connectors are used with blown fibre or mini-cable, with distances between the fibre distribution points (FDPs) and the premises potentially running as far as two kilometres. The duct (conduit) is usually made up of several sections joined using push-fit connectors, and the fibre is physically blown, using compressed air up to 15 bar pressure, fibre being further motivated through the duct using pinch rollers. The air effectively making the fibre float within the duct thus reduces friction, while the pinch rollers aid momentum and provide a means to monitor the installed fibre length.

‘The accuracy and smoothness of the duct’s internal gallery is crucial to avoid disruption of the blowing of the fibre – as is, of course, the push-fit connection between the sections of duct. The ducts are typically installed directly (direct buried) or indirectly (within protective ducting) in the ground unpopulated, and then the fibre or mini-cable is blown between distribution points or to the subscribing premises. It is crucial that the adjoining sections of duct line up perfectly, thereby ensuring the smooth transition of fibre through the intersections. The implications of a poor connection or subsequent connector failure can involve civil engineering works and the considerable associated disruption, cost and customer inconvenience’.

John Guest’s typical customers in the fibre systems arena are system providers, utility companies and installation contractors – ‘typically whoever is ultimately responsible for the installation reliability should have a vested interest in what is being put in the ground,’ said Hall.

He continued: ‘The benefit of a post-installed blown fibre system as opposed to a pre-installed system is that you can install fibre point-to-point without corrupting light transmission by the need to fusion splice at each directional change – a problem encountered with pre-made fibre cables at diverging distribution points requiring fibre fusion splicing or other mechanical junction, usually with an associated degradation in performance. The other big advantage is that additional fibres can be added or upgraded over time; capacity being restricted by the internal diameter of the duct.’

While fibre optics currently represent a small part of John Guest’s business it is growing fast, with turnover up significantly in the last 12 months.

The company supplies components and provides after-sales support to its customers but doesn’t get involved in installation. Hall said: ‘Fibre installation has reduced significantly in complexity over the years – the aim is to fit and forget, providing ‘sleep-at-night’ confidence. However, the connectors are often used in very technically and environmentally demanding areas – and while the connector may appear a relatively simple and insignificant consumable component, the implications of failure are often considerable and therefore connector decision should not be taken lightly – excuse the pun’.

While John Guest has competitors, Hall says the company ‘has quality and experience on its side’. He added: ‘John Guest is the standard rather than just a brand; we invented the push-fit connector, after all.

‘Reliability is absolutely essential. Unlike all other application areas we operate in – where if there is a problem you can shut off system pressure and replace the connector, in blown fibre – if the system is populated you must first de-install the fibre point-to-point, replace the connector and re-install fibre point-to-point. Replacement of the connector once populated with fibre is complex, so long-term reliability is essential’.

Hall believes the quality and reliability stands the company in good stead for the future. He concluded: ‘Fibre to the home (FTTH) is growing fast around the world and it is proving to be a good market for us after considerable up-front investment; we have developed a significant range of blown fibre connectors specifically for the FTTH market. Of course, as we are well aware, the FTTH market is ironically less developed here in the UK than in many other countries. But activity in the UK is increasing to satisfy a growing demand and John Guest is well placed to support this.

‘And while we remain a family owned independent company, manufacturing in the UK, we are a truly global operation – with 10 fully owned subsidiary companies providing marketing, stock-holding and after-sales support around the globe, and with distribution partners in more than 60 countries. We are very proud of that.’

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