OUR NOISY TRAM CARS.

Dominion, Volume 2, Issue 472, 2 April 1909, Page 6

OUR NOISY TRAM CARS.

PROBABLE CAUSE AND POSSIBLE REMEDY. AN INTERESTING SUBJECT. While the statement recently mado by a visitor that Wellington has the noisiest tramcars in New Zealand may not ho correct, the din sot up by passing cars, especially in Lambton Quay, has liecn tho source of considerable comment of late. From inquiries that have been mado, it seems that tho noiso is duo to corrugation which has attacked tho rails. When a rail is attacked, tho upper surfaco becomes wavy with undulations two or three inches wido, running transverse to tho rail. Though not serious at first, tho corrugation gradually increases in depth until the rail has tho' appearance of a rack. When tho corrugation becomes badly dovoloped on the rails, a similar corrugation appears in the tread of tho car wheels. Corrugation is ono of tho most pressing problems which tramway engineers havo to face at present, and, in Wellington, both Mr. Stuart Richardson, tho tramways engineer, and Mr. W. H. Morton, tho city engineer, have been giving tho matter very closo attention for somo timo past. Comparatively few tramway systems can claim an absolute freedom from this rail trouble, and the manager of tho Glasgow Corporation tramways stated a few months ago that ho estimated rail corrugation cost his system annually anything from £10,000 to £15,000. During tho last five years, scores of theories havo boon brought forward as to tho caiiso of this phenomenon, but up to the present no singlo theory has mot with general acceptance. Among tho causes which havo been suggested, tho following are mentioned :—Tho process of rolling tho rails at tho steel works; tho chemical composition of tho rails; tho construction of the track: vibration of the track set up by tho rolling stock; skidding of wheels and grit on tho rails; defects in the constni,tion of the car truck and equipment, etc. Tho ravages of corrugation appear on a straight track as well as on curves, and they spread along tho rails in patches sovcral chains in length. In Wellington the trouble has become very marked during tho last two years, especially in certain places along Lambton Quay, and, until recently, very little success has attended the attempts to remove the corrugation. A grinding device lias been designed by Mr. Leah, tho car-shed superintendent, and tho tests which havo been carried out lately have proved satisfactory. This apparatus, which consists of shoes carrying carborundum blocks, is attached to a car truck by means of springs. The pressure required on the grinding blocks is applied from . tho inside of the car by means of hand- , wheels. When in operation tho car is run '. backwards and forwards over tho defective ! track, with tho necessary pressure applied to \ tho grinding shoes. As tho blocks move • along tho rails a supply of carborundum '< powder is fod on to the rail in front of tho j block by means of small pipes. , A Doshnion representative accompanied ] Mr. M. Cable, assistant electrical cngincor, ] and witnessed tho process yesterday morn- , ing, and was able to observe that the prcs- ] sure of tho glass-liko powder on tho un- ] dulations of tho rails had tho effect of slightly , but distinctly reducing them. Tho process isa very slow one, but it is to bo persevered with, and a car will bo occupied at tho grinding from midnight till between 2 a.m. and 3 a.m. for a considerable period, as tho work cannot bo proceeded with whilo tho cars are ' using the line. Every precaution will ba ■ taken to run the car as quietly as possible, i so as not to disturb those residing near 1 the tram routes. ] It is not claimed that the devico will result 1 in preventing the noisy car nuisance for all 1 time, but that it will bo abated for six > months or so, when further application of tho ; grinder will bo required. i