RAILWAY SHOPS AND MACHIN ERY. Railway buildings and machinery are required for the maintenance and repair of loco motives and cars and for their cleaning, inspec tion and storage. Few railways build locomo tives on a large scale, although their engineers design them. Many railways build freight cars and sometimes passenger cars, but both cars and locomotives are built mainly by private firms. See RAILWAY CAas; LOCOMOTIVE.
Repair work, however, must be done by every railway. Usually there is one main shop plant where engines are sent for extensive re pair or rebuilding. There may be more than one, but the tendency is to concentrate the heaviest work, this being economical in time and cost and in machinery investment. Im portant division plants will have shops for gen eral repairs, and at the ends of all operating divisions there will be facilities for such light repairs as are needed to keep the equipment in service. Economic use of engines and cars re quires that they be kept in good condition, so that they may give the greatest mileage and service before they need be sent to the shops for extensive overhauling and repair. The plan and facilities at any shop plant will vary with its capacity, its site, its special purposes and the ideas of the designers. Provision must be made for future enlargement.
A large repair plant for locomotives will include a machine shop, erecting shop, boiler shop, tank— or tender — and sheet iron shop, iron foundry, pattern store and supply store house. The first five of these may be separate or grouped in two or more large buildings. The erecting shop, where the engines stand while being dismantled, repaired and assembled, may have several short transverse tracks for one or two engines each, or a few widely-spaced longi tudinal tracks. To avoid blocking these latter, the engines may be lifted. from their wheels and placed on the floor between or outside of the tracks. Pits in the tracks enable workmen to get under the engines.
Overhead traveling cranes shift the loco motives. With the longitudinal plan, two cranes
of 100 to 150 tons capacity must be used, one at each end of the engine. With the trans verse plan one 200 to 250-ton crane can do the work. Similar but lighter cranes at a lower elevation may handle the various parts and materials. Less expensive arrangements for division shops, to permit of removing the wheels, are power-operated screw jacks which lift the engine by beams under its ends, or drop pits beneath the tracks for small carrying hydraulic jacks which take the wheels from under the engines.
Longitudinal tracks extend through the building to yard connections, but the short transverse tracks extend usually through one side to the pit of a power-operated transfer table which has one track and travels laterally so as to connect this with any one of the tracks leading to the pit. Usually two buildings are on opposite sides of the transfer table, each with room for an engine to stand between it and the pit.
A large repair plant for car equipment will include a coach or passenger-car repair and erecting shop, coach paint shop, coach truck shop, freight-car repair shop, cabinet shop, woodworking shop and outdoor repair tracks.
Also a lumber yard and dry kiln. A black smith shop and machine shop are required, but in a combination plant these — and the foundry — may serve both the locomotive and car shops. Brass and steel castings are generally purchased.
Passenger car shops generally have short transverse tracks served by an outside transfer table, running between two buildings. Freight car repair work of the heavier class may be done in a building equipped with overhead cranes, but much ordinary repair is done on open tracks. These are arranged in pairs, the alternate wide spaces admitting intermediate tracks for trucks carrying materials. The re pair yard has pipes supplying water for refrig erator cars and compressed air for testing brakes and operating tools.