Locomotive Engine Running and Management

by Angus Sinclair

THE LOCOMOTIVE SLIDE-VALVE.

The nature of the service required of locomotive engines, especially those employed on fast-train service, makes it necessary that the steam-distribution gear shall be free from complication; and, for convenience in working the engine, it is essential that means should be provided for reversing the motion promptly, without endangering the working-parts. The valve-gear should also be capable of regulating the admission and exhaust of steam, so that the engine shall be able to maintain a high rate of speed, or to exert a great tractive force. These features are admirably combined in the valve-gear of the ordinary locomotive. Designers of this form of engine have given great consideration to the merit of simplicity. Numerous attempts have been made to displace the common D slide-valve, but every move in that direction has ended in failure.