Shetland Transport’s seaworthy Gray & Adams fridge trailers

Lerwick, Scotland: Shetland Transport has taken delivery of its latest batch of ‘ferry spec’ temperature-controlled Gray & Adams trailers.

The trailers incorporate a series of measures and uprated components to increase rigidity and protect them from damage in rough seas during ferry crossings.

Safe and secure… despite being firmly fixed to the deck, Shetland Transport’s trailers must still be able to withstand immense pressures in heavy seas

Every day up to a dozen Shetland Transport trailers make the 12-hour, overnight crossing to and from Aberdeen, or between the Orkneys and the mainland, a journey of up to eight hours.

Outbound trailers typically carry salmon – the Shetland Isles contributes more than half of Scotland’s farmed salmon production – as well as fresh, white and processed fish, and mussels, and return with fresh, chilled and frozen products for supermarkets and wholesalers.

Each trailer is secured prior to departure. Air is dumped from the suspension to prevent bouncing and the trailer’s king pin is shackled to a deck-mounted trestle with additional chain lashings on both sides.

Shetland Transport’s founder and managing director Hamish Balfour says if the trailers are not up to the job they are still likely to buckle and bend over time. “You can get rough seas in the English Channel too,” he says, “but the problem up here is the distances involved, the length of the journeys and the prolonged periods of stresses and strains to which our trailers are subjected.

“When the sea’s up the gravitational forces can be immense… as the ship descends into a trough they’re pushing down on the trailer; then, as it begins to rise back up the wave, everything starts moving in the opposite direction. Plus, of course, lateral forces will also be acting on the trailer throughout the voyage.”

“Twenty years ago our trailers were disintegrating because they couldn’t take the pressure. But the various strengthening measures that Gray & Adams builds into its ferry specification trailers mean we no longer have to worry. We’ve worked closely with the manufacturer as it has refined the design over the years, so that our latest trailers are the best yet.”

The Shetland Transport fleet is dominated by temperature-controlled 13.6m trailers manufactured to ferry specification by Gray & Adams. The latest are fitted with Thermo King fridges.

“Some of our G&A trailers are nearly 20 years old and still operational, because there’s a part of the business for which older trailers are perfectly suitable,” Balfour says. “Gray & Adams provide a first class aftercare service, supporting us with a rolling programme of refurbishment and accident damage repair, so the trailers always look nice and fresh from a presentational point of view.”