OT this ones for Eddie
开云体育I had heard of wheel spin damage this bad when a driver fell asleep for an extended period, but that was in Africa, so unlikely to be somewhere with snow on the ground! The railway administration's answer to the problem? It was a Diesel loco. They removed the driver's seats and made them stand. With rougher wheelspin control systems, BR used to get some rail burns to a shallow depth, mostly where heavy freights got brought to a stand on inclines and there had to be limits on those of course, as the hot spot creates a hard spot that can be brittle. The opposite problem is if a wheelset locks up and gets dragged a long distance. One of my earliest call outs was to a container train that had been stopped at Tyneside Central Freight yard in Gateshead, with flats about 6" long. The wagon repairer got there before me and had already released and isolated the brakes on that wagon in the middle of its train, suffering from an over enthusiastic slack adjuster. I took one look at those flats, and phoned control to tell them the wagon would have to stay there, please bring a wheelset & the breakdown crane. "Oh no it won't. Do you know what's in those containers?" "No idea at all." "Whisky". We agreed to let it go forward at walking pace to the container depot which was only about 4 miles away, rather than leave it parked in Gateshead of all places! Sorry, Gateshead, but think back to 1979! As it departed slowly past me, you could hear CLUNK chink -- CLUNK chink... I went home. It can get more serious - we've had a traction motor vibrated off the loco onto the track when a previously locked wheel decided to start rotating again, and the rear loco of a passenger train lifted off the track because the wheel flange on a dragged wheel set had got so high that it just lifted off at a cast steel crossing. God, - the paperwork! With modern traction, this should be a thing of the past, as the auto wheelspin control is infinitely superior. BR's class 60 (3100 HP) heavy freight locos, for which I was BR's commissioning engineer in the early 90s, were built with creep control from stationary and have been measured producing 500kN tractive effort from a loco weighing about 128 tonnes. You can put one against the buffers, apply full power and watch each of the 6 wheelsets independently turning VERY slowly, even if you oil one of them. You can google all these references, class 60 was an entirely British (apart from semi conductors of course!), pretty well entirely Hawker Siddeley product, and to this day can still pull the later General Motors (EMD, now Turner Diesel or possibly even Caterpillar) class 66 backwards. Eddie
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John
