Publication: Electric Railway Review
Chicago, IL, United States
CATENARY CONSTRUCTION ON THE SYRACUSE LAKE
SHORE & NORTHERN RAILROAD.
The Syracuse Lake Shore & Northern Railroad on January 25 placed a 4 1/2-mile stretch of catenary construction designed for single-phase current at 6,600 volts in operation. using direct current at 550 volts.
The road is at present about 12 miles long and cars are operated on a half-hour schedule from Syracuse to Baldwinsville, N. Y. As originally built the line was single track. following a circuitous route. When in September, 1905, the property was acquired by the present interests, the work of entirely rebuilding the road was undertaken. and this has included a second track, much of which has already been completed, as well as the relocation of the portion now equipped with catenary trolley construction. The road is to he extended from Baldwinsville, through Phoenix and Fulton to Oswego, making a line about 30 miles long. Much of the distance from Baldwinsville to Fulton is already graded.
The catenary work, as previously stated, Is designed for single-phase at 6,600 volts. but owing to the facts that but a small portion of the proposed work has thus far been completed and that the rolling stock is built for direct current, the road is being operated under the alternating-current-direct-current system. As will be seen from the accompanying engravings a single messenger cable is used with steel bridge construction. The bridges are located 200 feet apart on tangent and have a span of 30 feet. the track being laid on 12-foot cotters. The bents for the bridges are built of two 2-inch channel members, spaced 6 feet apart at the base. converging to 8 inches at the top and supported on concrete pedestals 20 Inches square and of varying depth according to the nature of the ground. The trusses have 6-inch channel top chords and 6-inch channel bottom chords set flanges down, the diagonal members being 5/8-inch rods and the struts 2 1/2 by 2 1/2 by 1/4 inch angles. The struts are flattened and bent over at the ends and riveted to the channels. Malleable iron pins for the porcelain insulators carrying the messenger cable are bolted to the top chord of the truss.
The messenger cable is 7/16-inch galvanized cable, furnished by the John S. Roebling's Sons Company and No. 0000 grooved copper wire, furnished by the same company, is used for the trolley wire. The trolley hangers are galvanized steel rods 3/4 inch in diameter, spaced 10 feet centers. These hangers are of the Ohio Brass Company's standard type, attached to the messenger cable with a sister hook, through the base of which the rod is threaded and drawn up tight against the messenger cable. The trolley wire is secured to the hanger by mechanical ears.
The catenary is strung for a net sag of 6 feet 6 inches at 100 degrees F. At 20 degrees F. the sag is about 5 feet 6 inches and the trolley is 12 inches higher at the center of the span than under the bridges, the height from rail to trolley being 18 feet. The bridge construction is designed for a wind pressure of 8 pounds per square foot on the trolley and messenger cables when covered with 1/2 inch of ice. A somewhat lower load is assumed on the high-tension wires, which are No. 2 copper. Under the assumed wind and ice load the unit strain on the bridge is 22,500 pounds per square inch. reduced for the compression members of the bridge, which is computed as a braced portal.