Railroading Terms - Part 6 - Model Train Help BlogModel Train Help Blog

January 21, 2006

Railroading Terms – Part 6

This model railroad posting will list various railroading terms over the next few weeks. These railroad terms relate to braking:

Brake Cylinder
A cylinder containing a piston and piston rod. When compressed air is admitted into the cylinder, it forces the piston outward, which applies the brake. When the compressed air is exhausted, a release spring coiled around the piston rod inside the cylinder returns the piston to its normal position, which releases the brake.

Brake Cylinder Release Valve
The valve that bleeds brake cylinder pressure then, if held open, will also bleed auxiliary and emergency reservoir pressures.

Brake Force
Refers to the ability of a train to stop. Brake force is usually based on tons per brake ratio, with the effect of increasing braking power when the tons per brake ration is reduced.

Brake Pipe Gradient
This is the difference in brake pipe pressure between the locomotive and the rear car of the train.

Normal Gradient:
The gradient level when the system is fully charged.

Inverse Gradient:
A temporary condition that exists when brake pipe pressure is higher at the rear of the train than at the front end of the train. This can happen at the beginning of a service brake application.

False Gradient:
Again, a temporary gradient when the system is less than fully charged.

Brake Shaft
A shaft on which a chain is wound and by which the power of a hand brake is applied to the wheels.

Brake Shoe
Friction material shaped to fit the tread of the wheel when the brakes are applied.