How do train wheels not skid or lose traction?

Question

Basically the title. Considering that train wheels are made of metals and run on metal tracks, how do they prevent wheelslip or loss of traction especially when starting with heavy loads or when going uphill? I’ve heard of sandboxes which can be used to provide more grip by spraying sand onto the track but I’m not sure if they’re still prevalent.

Thanks!

In: 72

Answer 1

newer train wheels are angled like trapezoidal. Keeps train centered on track especially when turning and differential speed happens. Pretty cool actually