Fastener with internal spring is not lost at sea

At the Southampton International Boat Show you can see a quick-action overcentre fastener which can withstand conditions where there is a lot of movement, shock and vibration. Protex Fasteners has added this quality by the incorporation of an internal spring.

The need for this type of fastener was first identified when the traditional models on centre consoles and lockers of RNLI rigid inflatable inshore lifeboats failed. Here the arduous working conditions and violent motion caused by buffeting waves at high speeds, coupled with over tensioning, resulted in coil binding and, ultimately, claw component through fatigue.

It was in order to overcome these faults that the model 71-2600 was developed. It features a strengthened claw component, giving all round heavier duty performance with an increased resistance to vibration – particularly lateral – due to the centrally located spring, and an increased claw length operating from the single compression trunnion.

The central compression spring allows a movement of 7mm. Beyond the maximum spring loading of 72kg, the trunnion compressing the spring meets a stop, thus avoiding any coil binding which could damage the spring. The overall length of the device is 122mm, its weight is only 0.162kg.

However, the new model 71-2600 in stainless steel promises to work very efficiently in this maritime situation, with an easy action, even spring force and high breaking strength of 580kg.

What is more, since it is designed with a narrow, channel section base, it is aesthetically attractive, being slim and exposing neither fixing holes nor mounting screws, thus deterring tampering.

A zinc-plated steel version of the fastener for less corrosive or otherwise hostile environments has a breaking strength of 660kg.

Both stainless and zinc-plated steel fasteners are available with safety catches.