Pneumatic Engine

a locomotive in mining to transport trains of trolley cars along underground mines that are hazardous owing to gas. They were first used in the late 1800’s in German mines, and they began to be used in the USSR in the 1960’s.

The pneumatic motors in the locomotive get their air supply from compressed-air tanks with a capacity of 1 to 2 cu m each at a pressure up to 22.5 meganewtons per sq m (225 atmospheres). They can move trains weighing 60-100 tons. The maximum length of a run with one charge of compressed air is usually no more than 5-6 km. Energy consumption is considerably greater than for electric locomotives. For this reason and also because of the frequent recharging of the tanks, pneumatic locomotives are only used in mines that are hazardous owing to gas.