A question on air brakes.

[10more years]

Agreed that all railroads have certain and different criteria for handbrakes. Usually, one of those requirements is that those handbrakes are "tested" to ensure that that car are secure.

[LocoCam]

On the BRSR, for example, we set all of the handbrakes when tying down the train.

WOW......Thats allot of brakes! The Class 1 I work for is min of 2, and must be tested not including the engines. That works out to almost always being 2 + engines. Some places have timetable instructions, but not anywhere I work.

[Engineer Spike]

The principle of thr automatic air brake is based on pressure imbalances. When a train is put together, the system is charged to the designated pressure. When the engineer makes a reduction, to apply the brakes, the control valves on all the cars sense the imbalance between the brake pipe and auxiliary reservoirs. The imbalance causes the control valves to direct air from the reservoirs, to the brake cylinders. This state remains until the release is signaled, or the air between the cylinder and reservoir leak off. The bleed rods will also deplete this pressure.


To release, the brake pipe pressure is increased. This signals the control valves to vent brake cylinder pressure to the atmosphere. At the same time, it recharges the reservoirs.