Straigthening of Railroad rails
Straigthening of Railroad rails
(OP)
A huge coal stacker reclaimer on rails had foundation embankment settlement. We are going to remediate the foundations. The owner wants the rails to be salvaged but they have been bent out of tolerance. Is there a practical way of straigthening heavy rails?






RE: Straigthening of Railroad rails
So it seems application of heat and a mattress able to reduce the rails to the wanted shape under conditions of heated plasticity and coercion and to the wanted tolerance would be required.
I think the rail replacement must be quite costly if such kind of equipment is not available locally to be worth the effort os seeking one from afar.
Then one needs to check what alterations the applied heat will cause in the rails and if they will remain within metallurgical and mechanical specifications and requirements.
RE: Straigthening of Railroad rails
1. You can heat the rail to bring it back to straight, but you will have a difficult time making it completely straight. It also requires condsideration into the air temperature. Hot and cold temps can have a big impact on rail.
2. The rail may have been in this postion for quite some time and portions of it may have a tendancy to want to return to this shape. You need a good rail base to resist this stress. This affects the foundation and connects of the rail to the base or foundation. You might be able to cut the rail into smaller sections to help reduce these stresses.
I would probably recommend selling the rail for scrap and buying new rail.
RE: Straigthening of Railroad rails
I think Heating high Carbon steel will embrittle it making it more susceptible to future problems.
Cold working would probably also not do as the rails are very heavy .
Merry Christmas
RE: Straigthening of Railroad rails
I'd have thought the heat input required to staignten a rail would be excessive.
Like the others I think replacing the damaged section is the way to go. How much steel are you talking about?
RE: Straigthening of Railroad rails
Regarding the metallurgy and effects of heating. For rail weighing 91-120 lbs/yard, a representative composition is 0.67-0.80% C, 0.70-1.00% Mn. 0.04% P (max) and 0.10-0.23% Si. After hot rolling, a controlled cooling is used to prevent shatter cracks. The rails are allowed to cool under 1000oF, then placed inside insulated chambers. The controlled cooling between 725 and 300oF (a minimum of 7 hours is required before reaching 300oF) allows formation of a tough, strong, pearlitic microstructure.
Hardening of the top and wear edge, primarily for rail used in heavy wear regions such as curves, can be accomplished by heating with either an inverted U-shaped induction coil or gas burners, followed by compressed air quenching. Residual heat results in tempering to a Brinell hardness between 321 and 388. Hardening of the rail web or base is undesirable.
Although this information refers to 30+ years old U.S. practices, I would not expect significant functional differences. Without either the specific heavy equipment for cold straightening or for controlled cooling after hot working, I would strongly advise against straightening rails. Straightening by a manufacturer is a possibility, although less feasible if the rail has been partially hardened
RE: Straigthening of Railroad rails