Electric Railway Journal · Vol. 61, No. 23 · June 9, 1923 · pp. 954-955.

Remodeled Electric Locomotive for Metropolitan Railway, England. One-hour rating is 1,200 hp. at 600 volts and 30 m.p.h.

Metropolitan Railway Locomotive Reconstruction. Important English Railway Remodels Score of Locomotives to Permit More Efficient Handling of London Suburban Traffic.

A large electric locomotive reconstruction job has recently been undertaken for the Metropolitan Railway, England. It comprises the rebuilding of twenty machines, resulting in virtually new equipment. The work is being done by Vickers, Ltd., the electrical apparatus being supplied by the Metropolitan-Vickers Electrical Company, Ltd. The locomotives are of simple construction, consisting of two trucks, carrying a steel cab mounted on a substantial steel underframe. This underframe takes the buffing stresses. The trucks carry each two motors, of 300 hp. capacity at 600 volts and at the one-hour rating. The one-hour rating of the locomotive as a whole is, therefore, 1,200 hp. The locomotive is provided with both vacuum and pressure brakes, the former being used in regular service and the latter for shifting purposes.

The control is of the Metropolitan-Vickers all-electric type, with automatic acceleration. All auxiliary apparatus is mounted in the center of the cab, leaving a passageway all around.

This road uses two contact rails, one for the positive and one for the negative current. The former is at the side of the track, the latter in the center. The locomotive, therefore, had to be supplied with two sets of collecting shoes. One set is connected to a positive busbar in a control cabinet at one end of the locomotive, while the other goes to a negative busbar at the other end of the locomotive.

The control is of the multiple-unit type, so that two or more locomotives can be operated from one master controller. Bus lines are also provided for connection with a power bus on the coaches, some of which are provided with auxiliary collecting shoes to insure continuity of contact with the conducting rails.

Particular interest attaches to the braking system, which is novel compared with American practice. To supply air for the pressure brakes, a compressor with a capacity of 38 cu.ft. displacement per minute, driven by an 8-hp. motor, is provided. For the vacuum brakes there are two exhausters, one to offset the effect of leaks in the vacuum train pipes and the other to provide sufficient capacity for releasing the brakes quickly. The brakes are interlocked with the motor control in such a way that current cannot be supplied to the motors unless the brakes are released. Similarly, the interlocks prevent operation of the motors unless one of the brake systems is ready for use.

The weight of the locomotive in working order is about 63 tons (2,000 lb.); its length over the buffers is 39-1/2 ft, its length over the body is 35 ft., and its width over the body is 8 ft.

The Metropolitan Railway, the operator of these locomotives, is one of the underground railways in London.

Engineer's Operating Position in Cab, Showing Also Some of the Control Apparatus in the Center of the Cab.

Sources

Electric Railway Journal, McGraw Hill Company, Digitized by Microsoft, Americana Collection, archive.org.