How do trains not derail on turns?

Maintaining Train Stability on Curves: The Role of Precision Wheel Guidance

When trains navigate curves, the forces acting upon them can be significant, posing the risk of derailment. However, specialized railway infrastructure ensures that trains remain safely on track, utilizing precise wheel guidance systems.

Specialized Rails: Guard Rails and Check Rails

Two critical components of wheel guidance are guard rails and check rails. Guard rails are installed along the outside of the curve, while check rails are placed on the inside. These rails serve different purposes:

• Guard rails: Prevent the wheels from climbing over the outer rail due to centrifugal force.
• Check rails: Guide the wheels back to the correct alignment if they deviate inwards towards the center of the curve.

Ensuring Precise Wheel Position

The precise alignment of these rails relative to the main rails is crucial. If the guard rail is too close to the main rail, it can cause excessive friction, while being too far away may allow the wheels to slip over. Similarly, the check rail must be positioned close enough to guide the wheels but not so close that it causes excessive wear or damage.

The Mechanics of Wheel Guidance

As the train approaches a curve, the wheels first encounter the guard rail. The centrifugal force exerted on the outer wheels causes them to press against the guard rail, preventing derailment. Simultaneously, the inner wheels are guided by the check rail, ensuring they stay within the track.

This synchronized guidance system ensures that the wheels remain firmly on the rails throughout the curve, regardless of the speed or weight of the train.

Conclusion

Precision wheel guidance is paramount for maintaining train stability on curves. Specialized rails such as guard rails and check rails work in tandem to ensure that wheels stay within the correct tracks, preventing derailment and ensuring a safe and efficient rail journey.