What is the minimum diameter for an iron on steel tread?

The minimum diameter for an iron on steel tread is critical for ensuring safety and effectiveness in rail operations. A 5/8" diameter is specified because it strikes a balance between providing sufficient strength and support without introducing excess weight or material that can lead to additional wear and tear. Treads that are too small may not adequately resist the forces experienced during service, such as the weight of the railcars or stresses from turning and braking, potentially leading to failure.

Selecting an appropriate diameter is important because it directly influences the performance of the rail and the safety of the rail transport system. An overly large tread might not be practical within the constraints of rail design and could negatively affect the dynamics of the railcars. Therefore, the 5/8" minimum size is established to ensure robust performance while maintaining the integrity and functionality of the rail system.