Com: David richards : Fantastic, I studied this process 50 years ago as a welding apprentice but never saw it before, this joining of railway lines was the only application it was used for then.

For those that do not understand welding, it is still done today as before because while the set up is slower the overall process is faster than a manual process, the rail contour would be a pain to manually weld and dam.

Thermite welding deposits a very high quality weld and not to forget this is a "Hatfield Steel" an 11 - 14% Manganese steel, not so easy, except of course to you experts out there..

Com: Railroad : OK to answer questions about what railroads weld rails together is to remove the joint from the track after all the joint is the weakest part of the railroad track structure. here in the united States almost all of the Major railroads have replaced their mainlines with CWR.

but on the other side of the coin is CWR requires more frequent inspections both during periods of extreme heat or cold and the railroads have to have a policy in place for inspection repair and maintenance of CWR which this policy is also submitted to the FRA.

and yes to answer another question hitting the fresh weld with a hammer could in fact cause a internal rail defect that is why railroads have test trucks that test the rail ultrasonically for these before they fail. and yes I happen to work for the railroad as a track inspector