The Concept of a Brake Van
Rather than brake every vehicle in the train, the alternative was to put one braked vehicle at the back to balance the force created by the brakes on the engine. The brake van would have one man aboard, the guard, who knew where the downhill stretches of track were located. He would then wind on a powerful handbrake to provide enough force to keep the couplings tight and prevent the wagons from hitting one another. The van and the guard also had a safety purpose. Sometimes, a coupling would come undone and the train would 'break' into two parts. The guard would use his brake to bring the back half safely to a halt before walking back down the track to put warning signals on the track - such as red lamps and explosive detonators - which would warn the driver of the next train in time to prevent a collision. Even after the fitment of continuous vacuum brakes to goods trains became widespread, brake vans were still carried. Although the vacuum brake would automatically stop the train in the event of a break, the guard was still needed to protect the train from collision. Nowadays, electronic track circuits will detect a stationary train on the track; signalling staff are instantly awareof it so they can stop the following train with the ordinary signalling system. The GNR[I] 20 ton van
No. 81 was one of many identical vehicles made in the late 1940s to a design typical of the time. The van runs on four wheels, and its brakes are like any other railway vehicle, with large iron shoes pressing against the tyres of the wheels to create friction. To maximise the braking force, the van uses two shoes on each wheel. A large amount of friction between the wheel and the rail was also needed, so ballast was added to make the weight up to 20 imperial tons (approximately equal to 20 metric tonnes). This could be concrete, or, as often happened, recycled iron such as worn-out locomotive parts. The vans had strong steel frames, to which wooden planks were bolted to create the upper bodywork. There was a 'verandah' at each end, covered by the roof but open at the sides and ends for good visibility. The centre of the van was a fully-enclosed room. Here the guard had a desk, some bench seats and a small stove for burning wood or coal to keep him warm in winter. An iron pillar in the middle of this room supported a large wheel at waist height, which operated the brakes on the van. While not luxurious, the van was at least warm and a shelter from wind and rain.
Van No. 81
In 2006, the two ballast compartments were emptied (to lighten the van so it could be lifted by a crane, and so the condition of the tanks could be assessed). The ballast was found to be scrap iron, and contained many interesting items. There were some 150 coach brake blocks - strangely, some seem to be unworn - a length of rail, several wagon axleboxes, and some axlebox covers dated 1869. Most intriguingly of all, several connecting rod parts were unearthed - part of a steam engine's power transmission system. Altogether, we found two big end straps and three of what we take to be small ends. However, they are to a very old design indeed, already at least 50 years out of date when the van was built. Presumably the builders at Dundalk used scrap iron that was surplus to requirements to fill the van. Pictures of the finds can be seen in the website's photonews section.
Decline
Restoration
No.81 was the first choice of vehicle. One reason was that it was easily the sorriest-looking piece of rolling stock on the site! Not only were the floor, sides and roof all about to collapse, but the strange angle at which it had derailed left it with only one wheel on the track. The project was therefore clearly a challenge, but one that, if faced, would make a significant difference to improving the state of our collection. The metal frame of the van appeared to be virtually intact, and the replacement of the wood appeared to be at least simple if not easy.
In practical terms, a use for the van was forseen in that it would allow the annual train rides to make use of our historic wooden-bodied coaches. Since the beginning of 2004, a total ban on these coaches was initiated on NIR for safety reasons, so short train rides remained their only possible use - however, we do not have a brake coach that is pointing in the needed direction. Restoring another vehicle is actually easier than arranging for the coach to be turned, because this would need a long run around the triangle at Belfast, and would require the ban to be lifted first! In recent years we have used the 1960s Mark 2 coaches for the "Summer Steam" operations, but the idea of using some of the much older coaches is very attractive. The volunteers set to work with great gusto in the summer of 2006, and thanks to the Northern Ireland Museums Council and private donations, funding has been secured that should be sufficient for a complete refurbishment to running order. You too can help with this project - all you need is RPSI membership and a pair of steel-toed boots (some age issues will also apply). The ongoing story of the restoration can be followed on our photonews pages. Here's a glimpse of where we are now as we enter 2007, and a taster of the skills you could learn if youcome along to help us! L-R: The van inside the locomotive workshop
in the winter of 2006; a volunteer being taught to use an acetylene cutter;
the nearly forgotten art of scraping a wheel bearing being learned on the
job by one of our younger members; routing planks to shape; sawing some
of the large floorboards, and the gentler recreation of painting.
Keeping Steam and Diesel alive in Ireland since 1964 |
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