PAEROA RAILWAY BRIDGE

Hauraki Plains Gazette, Volume XXXVII, Issue 4941, 19 February 1926, Page 2

PAEROA RAILWAY BRIDGE

INTEKEBTINU TASK UHSlsuw.vu*» MOVING A 12-TON GIRDER. The work of the erection of the , new double-track railway bridge over the Ohinemuri River at Paeroa to proceeding apace. . .. - On afternoon a very interesting piece of work, calling-for skill .and judgment,'was- carried out in , the presence of the assistant engineer, N.Z. Railways (Mr J. Langbein), -foreman of works (Mr W. Waterhouse), and the bridge foreman (Mr T. Harri-. son). ’ ( -.. . .' After waiting many months for .the plate steel- girders to arrive from England these. were received ( at Paeroa. about a week ago, and the assembling of the mass of steel on two of them was comoleted early this week. This work was carried out on t,he town side of the river near ,the site of the bridge. The next.step was to move the huge structure, 60ft in length, 6ft high, and weighing a Little.over 12 tons, to its- permanent position; on the trestles built of ironbark on an; under-struc- - ture of similar nature. Apart from having to move the girder off itis - temporary staging on to the bridge stringers, it had .to be pulled a distance of 140 ft .to -reach its, final position. .was’ ingeniously earthed out. The girder was first of ajl jacked up, and a number of small iron rollers were placed un-" der at a distance-of three feet apart, and then the girder .Was lowered until it rested on the rollers. To the front portion of the girder was attached a wire rope, which in-turn was attached to a windials's. securely bolted down on a trestle on the .opposite, bank of • the river. On each-side of ,the two ends’ of the girder there were blocks and tackles placed as an emergency,. should the steel-work' show any signs okca.nting over from .the top. . . At a given signal; two men oh the windlass slowly-but surely drew the mass of steel across the stringers into position, the whole operation being \ carried out without,' a hitch.' A sigh of relief was heard from the. engineers as the girder reached it permanent position. There are still more girders of similar size .to be so placed, but .the workmen have now a knowledge of’ what is required,. and the work will be carried out. with greater confidence. Each span girder costs approximately; apd if one should fall when in mid-stream its recovery. would be problematical, on account of its weight and the depth of i the river from the top of the bridge. , . In passing it is interesting to record that the .Paeroa bridge will possess the longest steel-plate grider! span in the Auckland (section. For the purpose of assembling the platep- which comprise "the finished girddr an Inger-soll-Rand pneumatic riveter is being used. With this machine two men can drive about 200 rivets a day/ according to size, as they vary from inches to 2 3 A inches'. The saving that this compressed air machine makes can be judged by the fact that four men would be doing well to drive fifty rivets a, day by hand labour. . No delay win be caused in the completion of the structure now the ne'ces-. sary gear is to hand, and it is, expected to have.the work sufficiently far advanced to carry a single set of rails / within three months. . > ■