I had a similar problem a few months ago, when rebuilding guiding wheels for lock gate doors in a port ; the wheels were worn on the flanges and the rolling surface ; it was a solid, cast carbon steel wheel, diameter about 1 meter, total weight 1.5 ton ; a martensitic hardsurfacing layer on top was requested, but the intermediate layers were welded with an ordinary EL12 wire ; we did both with and without preheating

We found in both cases cold cracks, especially at the flange side ;
the best result (with an occasionally crack) was obtained by preheating up to 250°C, maintaining the temperature with fixed oxygen/propane burners ; directly after welding you should wrap the wheel in a blanket to allow very slow cooling (48 hours) ; unwrapping can be done when the temperature of the surface is below 70°C ; you should use a high basic flux in order to minimise the risk of hydrogen cracks ; for your information : it was a cast steel, with a lot of impurities, made in the early 50's ...

In addition, if you want to avoid preheating and cracks you can weld directly on the cold wheel with a 307 type stainless (18Cr-8Ni-6Mn) ; but this will be more expensive !

Tram wheels (in Europe) are often rebuilt with this technique !