Ed, In the real world Continuous Weld Rail is laid at a temperature where the maximum expansion is expected to occur. This is precalulated for the region or area of the country where the track is located. If the proper temerature of the rail cannot be achieved, then the rail is heated until it expands to that temperature then welded together. Because steel has tremendous tensile strength, when it cools there isn't an alignment problem if the rail is properly secured. The contraction during cooling is more or less absorbed by the rail. (Problems sometimes occur when there is a defect in the steel and the cooling can cause a rail to break, but that's not typical) Heat expansion is the bigger problem.
I guess we could use this principal in model railroading, but then we'd melt all those plastic ties:) Bob Frascella Wenham, MA On Mon, Mar 12, 2012 at 2:25 AM, Ed <[email protected]> wrote: > ** > > > > Not much of the track is soldered together > > This first kink was with SHS flex track. > > I wonder if the size of the rail has any effect on the expansion. > > The material the rail is made from will determine the amount of expansion. > Different materials will expand at differing rates. > > > > I tried to not go end to end tight on the rails. I > > guess the rails will show be where I could have left more space! > > Bill Lane > > You might want to visually inspect those "former" gaps on a warm/hot day. > If the ends of the rails now touch, that would be a good place to cut a new > larger gap before the pressure builds up and leads to a kink. > > Question: In the real world, how do RRs prevent heat kinks when welded > rail is used for l-o-n-g stretches of track? With welded rail, there are no > slipping expansion joints -- or are there? > > Cheers...Ed L. > www.sscale.org > > >
