FAST WORK

Poverty Bay Herald, Volume LIII, Issue 16234, 7 January 1927, Page 11

FAST WORK

A BLOCK-YARD RECORD

PLANT NOT COMPLETE

A question was raised by a member flr' >!' (lu 1 OUb'oriie Harbor Board at a re- 1 ■cut meeting concerning the working) ■ if the Kaiti (dockyard mechanism. Tliell; I'ligineer stated en -hat occasion that I ill parts of. the machinery wire work- 1 ing satisfactorily, save for the scraper I •onveyor, for which a new part had I liad to be secured before it could" be I put into operation. To-day the con-jR veyor is working satisfactorily, and fast time is being mail' 1 in the casting if the blocks for the new harbor works. The lay-out of the blockyard has Necn explained in a previous article, nit it is necessary to see the plant in[ iperation to appreciate the saving of labor effected- The central feature >:' the block-yard is, of course, the big lower in which the concrete-mixing is| lone, I.ul (here are other features hardly less interesting, including thej ramps, for shingle, sand and stone, audi Ike (ioliath crane intended for hahdling the heavy blocks of concrete '"hiil! the yard will be turning out steadily, it is hoped, from now on. A pressman visited the plant this morning, and watched in turn the various processes through which the materials pass before their production' as concrete; the simplicity of the methods employed was at once apparent, and consideration of the fact that many thousands (if block* will be required in the construction of the breakwaters and walls of the harbor; impressed the watcher with the fact that the cost of the great structures should be saved over and over again in the saving of labor. As the layout of the construction yard nearer town was justified by the results ™ achieved, so the money spent on preparing the block-yard seems destined to prove a highly profitable invest- « inent. MINIMUM OF MANUAL LABOR The processes through which the materials pass involve a minimum of manual labor. From each of the -lacks under the respective ramps, stone, gravel, or sand is carried on a covered bolt conveyor into the base if the tower where the mixing machinery is concentrated. The sand,! iiul gravel are immediately elevated' to the screens at the top of the tower, but the stones are passed through acrusher before dropping into the buckets of the elevator. Revolving] graders, similar in principle to those st en at quarries, and sometimes on big road jobs, sort the materials into vari-| -us bins according to size, and eachj 1 the bins is connected directly to plages suspended above the mixerFi'hritc. The guages are emptied by Ike movement of a lever, and' Sited -igain by a similar operation. Two men are engaged at present in keeping the mixer a giant drum, tilled 'nut operating, the power being supplied by big electric motors in the I a semen tof the tower. Water runs into the druiu automatically, and ivhen the mixture is ready, court to is shot into a holder from which it is released slowly on to the platform of the scraper-conveyor, whence it, is carried out to the moulds awaiting it. Within 2j hours of the conveyor being put into operation, 30 ['our-ton blocks had been' mauufactur:d, and in due course these will be removed to storage for maturing, leaving the construction floor available for later relays of blocks. The working of the big crane is fas-] /mating to watch, for despite its bulk] and apparant weight, the structure is* i asily controlled and operates at a surprising speed. The power is oh-im tained from a boiler similar to those H» used en the pile-driving frames, and | ■ portions of the running gear haw ■ Icon salvaged from the old si eel crane I ■ used oa the breakwater 40 years ago. ■ Pivoting on the end, the crane can be swung on its circular rails at a rate - of 200£t'. a minute, and can carry a p weight: of 20 tons without serious strain. On The occasion of one test,;B a 20-ton block of concrete was lifted 8 in the centre of the span, and the de- | flection of the crane amounted to only 1 n quarter of an inch. No' tumble f should be experienced, therefore, in B handling the lighter blocks, which are S being manufactured in large numbers. I