ELECTRIFICATION

Hokitika Guardian, 1 May 1928, Page 3

ELECTRIFICATION

BIG JOBS IN CHRISTCHURCH. 'WELLINGTON, April 28. The signal and electrical branch of the Railway Department is carrying out two extensive works in Christchurch, and is making progress well in line with the programme. Work in connection with the electrification ol the Lyttetlon tunnel and the section of railway beweeii the port and the city has gone ahead with such expedition that it is easy to predict that before the end of this year, electric locomotives will he hauling the traffic. A comprehensive survey of the work in hand was obtained from the head of the signal and electrical branch of the service. Work in the tunnel is about half a mile inside, li has liceu found necessary to cut away the roof in many places to give proper clearance for the contact wires, hut the worst of these places have heen dealt witli. and the wiring is going on up to programme time. The rock of the. I illinel—much ol it is unlined—-i- very hard, hut compressed ail drills make it easy to carry oui i lie Inn ings. A compressor is installed at the I loathbqic end of i lie tunnel. To lix the j ring hulls suspending the Hiring, air drills imiko tlm hole- in tin- rock and (•unioi ossod air ai SUlhs lo the square inch drive- lenient through a cement gll'.. making ;1 very solid hill of the sealing in of tlie si'.* bolts.

The Public Winks Department's programme in <viiiicciinii with electriiiiatiou involves the provision of ll.ialil mil power, ami Lite erection nl it -uh-stat inti, which i> proceeding according to t inie-lalile. Sis electric locomotives needl'd lor the work of the elect rilied section are being built in England, and i!

is expected (iml 'lie manufad mvr will he able to make delivery before file end of the year, ti> .stipulated in the contract. These locomotive.- are to he housed in a portion of the old engine shod nl Lin wood, which is now being altered lor the purpose, two roads in this shed being electrified. :inil the space boxed olf from that required for the steam locomotives.

Electrification of the tracks involves bonding of the rails for the return current, and this work will shortly he put in hand. No track alterations are needed, and the task is simple. It is proposed to electrify the track at the port to the point' at which trains for the ferry wharf have to he taken before being hacked to the wharf, and it is not intended to carry the electric overhead system to the wharf itself. At the Christchurch end the electric system will run to Colombo .Street and will include a good many of the yard tracks. With the exception of four, all the poll's lor the overhead equipment are erected, and the Department- is waiting for the completion of the work in the tunnel to release the air compressor its some concrete has to lie drilled out at Lyttelton near I lie wharves, before the final poles can he placed in position. Cross wires for the cross catenaries are being prepare I for hanging, and the insulators arrived on a recent overseas steamer. As soon as they are delivered at Lyttelton. the department will commence to run out the ad mil power wires which are suspended from the cate-

naries. Some trial lengths will lie run on! in a few days' time. The erection of the overhead equipment involves a good deal of carelul planning and thorough workmanship. While, the catenary wires, from which the power wires arc suspended, will show a graceful droop between the .suspension points, the trolly wire itself will he kept perfectly horizontal. The stresses have heen worked mit beforehand, stronv: springs will he fitted to the catenaries -o as to maintain the required -Irani, ami t in* calculated tension will la applied hy dyn.om.otei winches