Railway Wheel Set 1.material:cast iron or cast steel 2.diameter : 300mm, 350mm, 400mm, 450mm, etc. 3.Heavy loading Railway Wheel Set:1. material: cast steel or cast iron 2. constitute: two wheels, one axle, four bearings, and other parts.3. loading capacity: 1-25tons, each one is ok.4. wheel sets gauge: 600mm, 762mm, 900mm, and etc.5. the type of the wheels: hollow wheel sets and solid wheel sets ...