GOLDEN BAY CEMENT WORKS.

Dominion, Volume 5, Issue 1372, 24 February 1912, Page 18

GOLDEN BAY CEMENT WORKS.

IMPORTANT NEW INDUSTRY.

AN INEXHAUSTIBLE SUPPLY OF

MATERIAL

DESCRIPTION OF THE WORKS,

li-'ioM.-of the quiet picturesque inlets characteristic of Golden Bay, and not , far. from' where Abel Tasmnn experienced the murderous hospitality of the New Zealand Native, lies the narrow valley of Tarakohe." Its landmarks, are majestic— huge masses of limestone cliff, which rise precipitously from the-water's edge, and, rearing their hoary heads, battlement upon battlement, to a height of hundreds of •feet.''With its craggy outlines, the forefront of. the conveys the appearance of a Brobdinagian castle, bearing the-marks upon .its features of many a Titanic, bombardment in the thousands of years' if has faced the fury of the elements. And in the dark blue waters which lap in tho shadows of the frowning ; --cliffs : are interspersed great blocks of '-.limestone masonry, a sacrifice to the relentless war ever going on between the kb. and the.land. TJp the valley tho hills rise o'n-e»ch : sido in ihillocks and ledges to..heights.of 500 feet.,..

A HUGE INDUSTRY.' There was a time when very little disturbed the serenity of tho little valley., hut now a transformation lias taken place. A hugo collection of corrugated iron buildings has made its appearance on the flat, scores of men are ahout tho place; from ' within comes tho deafening rear of hundreds of tons of machinery in motion; and from the smoke-stacks there helches out great spiral clouds of smoke wMch'Vin" the day. timo--may.be' seen hy passing steamers miles"out to sea. Night and day, from one end of the twenty-four ■hours to the other, there is the constant •crunching souild of machinery, the neverending smoke clouds, tho swift hurrying motions of the human units, and incredible as it may appear' this scone is likely . to reproduce itself, ■ day, by day, for many hundreds of years,'' and long after the "groat-grandchildron of future generations are laid" in the dust." The reason is that , -IhVfactbryreferred "to is' a cement works,.] 'the'cement'works'of the iGolden Bay Cement' Works, Ltd.,'bpe'rating upon an in*eihau3tii)le'supply of,limestone, and marl' covering hundreds of acres of land. Cc.,ment,ia. going to plaj a most °jlirf"itf'the^futuro'Sn'fl'ding'and architect ~turai.history of New Zealand. Year hy 'year,"'tihiher is becoming scarcer -scarcer, and it is only a matter of a comtpaVatiyely " short; period when residences and' dwellings will have to be erected in bnCk r and,,stone, and .all business premises and puhlio buildings of any consequence in reinforced;concrcte. In all these /methods of :hnilding cement is one of the "great; tho greatest, factor, so much so that even now the demand for this article '-'within the Dominion exceeds the 6uppiy, and. although the dnty is heavy, importations of the stuff have to be made from abroad. Prom investigations and reports, which were made amongst othorehy Mr. James Marchbanks, M.lnst. C.E., late Chief Engineer to the Wellington-Mana-watu railway, Mr. L. H. Eeynolds, C.E., Mr. J. A. M'Laren, late manager of the New Zealand Portland Cement Company' 3 Works, and from the result of an analysis by Professor M'Laurin, it was decided that .the Tarakohe. property was an admirable proposition for the manufacture, of high-grade Portland cement and hydraulic and agricultural lime. Tie.necewaxy materials required for '■'. '.mUtqra in th« work "of manufacture were '"'■ found to be all on the property. A site could to Detected right in the centre of trade,/north and wrath; with a water frontage, gMng a depth of from 12 to 20 {est, and tho company was therefore leanbhed iomo five yeara ago, with a capital of «5,000J!1 ihaTes, which later was in- ! creased to 60,000 £1 eharea. I

THE PROPERTY. , ■Itte jwpwty of the Golden Bay Cement Works, Ltd., la dtuaied on the shores of lh« wrath-east rids of Golden Bay, two mflea from the Tata Islands, 35 miles by

sea from Nelson, and 110 milca from Wellington.- The whole of the plant, machinery, and buildings lio in a limestone valley, Beven miles by a good Toad from Takaka, a thriving town about the size

of Motueka. The property of the company comprises some six hundred odd acres. A Dojhkioii representative recent ly visited the fllaoe and saw for himself the magnitude of the works. The trip down' was made in the Golden Bay Ship-

ping Company'H Hina, and occupied six hours, inclusive of the stoppages at Totaranui and Tonga, two of- the little inlcta which are such a feature of Golden Bay. One of the places passed is Waramanga Bay, where Tasman sustained ft murderous attack by New Zealand Natives. Tho prosenco of the big factory was indicated by groat smok« clouds, which could be 6eeu for milea before the steamer arrived at tho company's wharf, a substantial structure which runs out from the factory worka to a limestone bluff, where there is a depth of from 12 to 15 feet of water at low tide. Features which struck one on entering the harbour wore the

limestone cliffs and bluffe, -which fronted the -rater's edge, and roso from 150 to 250 feet, thence extending back in broken lines on each side of the factory. Farther back these hoighta roso to something over 500 feet, amongst them being prominent formations of mad, bo necessary in tho manufacture of cement. It may be said that this combination of limestone and marl is one of the most extraordinary deposits of its kind, and so far as is known has not been met with in any other limestone country in New Zealand, and the supply of. material is practically inexhaustible. The works are tituated right up against the cliffs which are at present being quarried, the limestone excavation being within a few yards of tho works, and the marl quarry only some few ohains away. The stuff is therefore being run into tho works at a' minimum of coat.

THE DIRECTORATE AND OFFICIALS. , Before describing the plant, one or two particulars regarding the company which has inaugurated this new industry may bo of interest. As is usual when starting enterprises of this description, the promoters at the outsot met with

considerable difficulties. However, rh"Y were eventually overcome, and the company floated. Tho following art vhs directors:—Dr. C. Prendergast Knight (chairman), and Messrs. W. M. Hanncy (managing director), Charles Stewart, G.

Wilson, Captain C. M'Arthur, and J. A. Plimmer., Mr. E. M. Boulton is secretary, Mr. J. A. J. M'Lnren works manager, and Mr. S. F. Strudwicke chemist. Mr. M'Laren was formerly manager of the New Zealand Portland Cement Company's works at Auckland, while Mr. Strudwicke is a thoroughly practical and experienced chemist from the Commonwealth Cement Works, Now South Wales.

THE MACHINERY. No pains were spared in obtaining expert advice in procuring the latest and most up-to-date plant, and when tenders were called, that of Messrs. Ernest Newell

and Company, England, was accepted for the cement manufacturing machinery, while thnt of Messrs. Turnbull and Jones, of Wellington, was accepted for iiio power and electrical plant. The plant throughout is very tine, and for its Bize is ono of tho most modern in the world. The machinery of a. cement manufacturing plant is of a most massive description. Some of the sections of tho iron and steel work weigh from two to nine tons tho single piece. These had to bo landed at tho Bite in barges (tho company's wharf was not then erected), and this work was both arduous and dangerous. Tho task, however, was accomplished without Hitch or accident—a feat in the circumstances in which the company was extremely fortunate. It was on February 8, 1910, that tho works manager, Mr. M'Laren, with a number of men, landed at Tarakohe in order to prepare the site and erect the foundations for the machinery, and the works were finally ready for manufacture. Tho article was first placed on the Dominion markets in November, 1911. ,

marine nature, showing sea mud and shells, and such fossil remains as large fish-bones and sharks' teeth. The marl is conveyed to the works in trucks, operated by a self-acting incline tram, the weight of the full trucks on their journey down to the crusher, pulling the empty ones back to the "face" again, ready for filling. The tram-line, which extends fourteen chains from tho works, has a capacity of delivering about 200 tons of stuff per day. Arriving at the crusher, the full trucks are tipped, ready for mixing with the ttone.

THE BUILDINGS. The buildings In all cover approximately an aggregate Bpaoe of 30,000 square feet, divided into the following buildings: —Crusher and raw stone storage buildings, dryer house and raw material grinding and mixing department, kiln and coal grinding buildings, clinker storage shed, cemont grinding and finishing buildings, silos bulk storage buildings, packing and bag storage buildings, power house, fitters' shop, offices and storerooms. In addition to these there is a large boardinghouse, also barracks, with plungo and shower bathrooms, supplied with hot and cold water, for the use of the workmen, and a dwelling for the manager and staff. A number of smaller buildings and tents dot the various portions of tho valley of this new township, the population of which now numbers 150 men, women, and children. Plans are now ready for further building in the shape of workmen's dwellings, which are to be commenced almost immediately. There arc in the district about thirty children, and on application has been put in to tho Education Board to erect a schoolhouse. This also will be erected ,is soon as possible. The place has already been scheduled as a post and telegraph station, the office being situated for the time being in the offices of tho company. The buildings, which range in height from 30 to 70 feet, are constructed of steel, iron, and wood, while the walls and roofs arc of corrugated iron. In order

CRUSHING. The limestone quarry is within a few yards of the works, and the material is I quarried and trucked, and dumped into a huge gyratory crushor of tho Gates type, with its proportion of marl mixturo, which is determined-by the chemist. The crusher, which appears to work, in a measure, on a gigantic pestle and mortar principle, is driven by a 50-h.p. electrical motor, and its huge maw has a capacity of' assimilating from 250 to 275 tons of stuff in one day. Tho noise created by. tho churning and tearing to pieces of tho limestone rock is of an almost deafening nature, and tho stones are broken to a fineness of one and a half-inch cubes and less, and the fragments are then conveyed by means of oblong iron receptacles on the chain-Bucket principle to what are known as storage hoppers, which have a capacity of 8(k tons.

DRYING. The material is then extracted by automatic shaking conveyers, aod delivered into a big revolving drying cylinder, which extracts the moisture by means.of hot gases. Thence the stuff is delivered into an elevator, which conveys it to large steel storage bins, with a capacity of about 300 tons.

GRINDING. In these processes the material has been ground smaller and smaller, and from tho storage bins it is delivered automatically to preliminary steel-ball grinding mills, worked on the Krupp principle, and with a capacity of turning out from 6 to 8 tons per hour, dependent, however, on the fineness required. By the time this process has been gone through 6tone and marl have been ground almost to a powder. There is further atomising to bo done, however, and the material is then conveyed by further automatic means to a huge tube mill, 2G feet long, sft. Gin. in diawtfer, and carrying a charge of flint

blasts at the New Plymouth oil wells. In order to fit it for its purpose this coal nlso goes through a very interesting process. It is first delivered into crushing rolls or disintegrators, thence it is conveyed into a cylindrical revolving drier of sufficient capacity to cope with the work. When delivered from the drier, the coal is fed automatically into a coal grinding tube mill, and pulverised to an extreme fineness. It is then relivcred by

,to show the magnitude of space covered by the various structures, it is worthy of note to remark that the corrugated iron weighed in all over CO tons; SELF-SUPPORTING "SKY-SCRAPER." Above the buildings three steel chimney stacks Tear themselves aloft to heights of 80, 100, and 137 feet. The two shorter ones are held by guys in the usual mannor, but the tallest "sky-scraper," which erects itself from the power-house, is what is known as "self-supporting," that is, it has no stays to maintain it in position. Instead of theso auxiliaries, the tube is embedded in a foundation of concrete and bricks measuring CO cubic yards, and going down over a depth of 12ft. to solid rock, and anchored beneath that by massive holding-down bolts. There, arc only'one or two other stacks of' this description in the Dominion, and the aspect of this cylinder, standing alone, unsupported, in tho' company's works, is one which. immediately strikes the eye of visitors, and the universal question put by them to the manager is: "What keeps that chimney standing up, und how high is itr"

MECHANICAL FEATURES. Tremendous mechanical force is required in the miuiiil'atture of cement, ami it is almost awe-inspiring to bo through the various departments and view the great moving pieces of machinery, breaking and grinding and crushing the rock to the various stages until it is finally finer than the sands of the sea shore. After tho crushing, the- stone is subjected to'a terrific heat of some 2000 or 3000 degrees Fahrenheit. Features in the machinery are the great cylindrical rotary drums for drying, grinding, and finishing, the immense rotary kiln, tho largest in the Dominion, tho ball tube mills, and tho huge gyratory rock-crusher. Alongside the machinery used in the cement-malting business the average county council stonecrusher is like a mosquito to an elephant.

PROCESS OF MANUFACTURE. The process of manufacture is most interesting. The marl is excavated by ths aid of explosives, such as gelignite and powdor. Tho formation of tho underground deposit* It U ialerortinj to note, ax* of t

pebbles, 13 tons in weight. It is not to be wondered at that when the stuff has emerged from this process, it has been ground to the necessary impalpable powder. When operating with its load, the mill has a total weight of 2G tons. The grinding mills are driven by an electric motor of 185 h.p., and by this time the product becomes technically known as "raw-meal."

MIXING. The next process is the placing of the "raw meal" into huge storage and mixing bins, three in number, and operated by a 15 and a 30 h.p. electric motor. The meal is mixed and remixed so as to ensure an even .quality, and when the mixing has been completed the material is automatically conveyed by spiral conveyers to a gigantic' rotary kiln, the largest of its kind in New Zealand, and here the stuff is burned into clinkers.

BURNING. " This kiln is 12S feet long and 8 reel, in 'diameter. With its brick limn.? and when charged with material it weighs 200 tons, ft revolves slowly at the rata of from i to 1! revolutions per minute, is driven by a 30 h.p. motor, and can get through from 73 to ilO tons of stuff per clay. Inside this tube the meal is swathed and wrapped in an absolute tempest ol lire, until the- burning material is transformed to. a flinty mass called clinker. One may imagine tho heat in this inferno when it is marked down at between 20:10 and 3000 degrees Fahrenheit. As tho drum, heated by blasts of finely pulverised coal dust slowly revolves round and round, there comes a wild shrieking wailing sound ns if from lost souls condemned for ever to tho everlasting torment of hell fire. The noise, however, is merely the wail of the blast. It is impossible.to gaze at the seething cauldron with the naked eye. This has to be done with the aid- of coloured glasses, through which may be seen tho whitehot glowing masses of forming and fluxing clinker, falling from the concave sides and gravitating towards the dclhery end of tho furnace. When blown in on tho furnaco tho finely pulverised coal- ! dust burns liko a gas-jot, its tlaro being I something idmUar to that of the gas and oil

nn elevator into a fino coal storage bin fTom where it is extracted and blown into the kiln by a blast, as previously mentioned. This goal plant is operated by a CO-h.p. motor. COOLING AND AERATING. The quantity'of coal rehired is regulated by a "speeder," and about per cent, is required to burn to clinker, When .sufficiently bunt the clinfcr is delivered 'through a chute into a revolving cooling

cylinder, and when cooled it is delivered from tho cylinder into an automatic weighing and receiving nincrinc. Thenco it is conveyed to tho clinker storage house fo- aeration purposes, after which the material is clevateJ by chainbucket elevators into a storage hopper above the finishing mills. From this hopper the .material is thrust, still automatically, into a preliminary rotary ball tube mill, feet long by 5 feet in diameter, and charged with'nine tons of steel balls, which effectually reduces the clinker again to a fine powder.

THE FINISHED ARTICLE. The next operation is b- place the powdcT automatically into a larg? finishing tube mill, 21 tons in weight, and operating a charge of llint pebbles, 12 tons in weight. This mill is 1:1 ieut lons hy 5 feet in diameter, and puts through tiom 3 to ■1 tons of finished cement per hour. A? will be .wen, by (ho lime the material has

reached this finishing mill a largo amount of it, compared to when it first entered the factory, has disappeared, mostly through the boat. From this finishing mill, the article emerges as cement ready for sfcrage. Tue ball tubo and the finishing mill are worked by a ISO-h.p. motor. STORING AND PACKING.! The cement is theu delivered by elevators and conveyers, and distributed into one of the twelve large bulk cement silohoppers, which are operated by SO-li.p.

motors, and is then discharged into nn automatic-weighing and recording machine. The material is extracted from the bottom of tho hoppers by an automatic conveyer, then elevated into pack-ing-house hoppers, where- it is bugged with machines, three in number, which bag, weigh, and count each at the rate of five tons per hour. The bags are then Bewn by hand, and stacked ready for shipment. The whole of' the work of manufacture from the time the stuff is placed in the crusher is by automatic

availablo and the above careful method! of testing, thoro is no difficulty in obtain' ing cement of a very high'standard, and which easily fulfils the stringent requirements of the British standard specifications, SHIPPING. When ready for shipping, the cement It loaded in trucks and conveyed down to tho company's whan' by means of an electrical haulage gear on Ilia endlei.srope system. The trucks are so con-

power. TESTING. It is most interesting to. note that during the. whole process of manufacturefrom the quarrying of the raw material to tho packing of the finished cement, continuous and elaborate tests are made in the laboratory by the chomist, Mr. Strudwicke. The raw materials arc checked by analysis, to ensure that tho correct proportions of limestone and marl are used in tho preparation of the raw meal, before it is fed to the kiln to be burnt into clinker. Then, while tho clinker is being ground, samples of the finished Portland cement arc taken, during every hour and carefully tested. Then, again, when the cement is being packed, every ton is subjected to further checking, by exhaustive tests, in order that the responsible official may be quite sure of the sound quality of the product before it leave? the works. The v is informed that with tiio raw materials

structed that the bodies can bo lifted wjth the loads complete, and lowered bodily into the ship's hold, and then emptied immediately by the aid of a lever, thus expediting the work and saving labour. THE POWER-HOUSE. In thto power-house two double Drum Babcock and Wilcox watertube boilers Bupply the steam to the engines operating the olootrio generator!. These boilers have a capacity of 1000 horse-power. In the engineroom there are two triple-expansion Bellies and Morcom engines attached direot to the electrlo generators, and working in combination with a Burface condensing plant and airpumps. The large engine has a capacity of 850 horse-power, while the email 0n« is of 150 horse-power, When generated at tho power-house the eleotrical power ie transmitted to the various motors by cables, and ia governed not only at the machines when operating, but is fully controlled at the Switchboard by the engineer in attendance. The wholo of the plant is electrioally-drivon by three of the most modem Westinghouso clectrio machines. MANUFACTURING CAPACITY, Tho present, manufacturing capacity of tho works is'from «0 to 500 tens per week, but shortly this will bo.inoreased up to 600 tons per week. So far as etorage is concerned, the silo storage-room oau accommodate about 2500 tons, while the big etorage department will take-about 1000 tons. The stock of coal ranges from 200 to 1000 tons. It is brought up from the ship's eido on the same principle on which the cement is Tailed down the wharf, and when it reaches its destination at the various portions of the works tho stuff is discharged by means' of on electric hoist. The wharf which runs down from tho works is a strong structure OGOft. long, and ships of 1500 tons have been tied up to it without any difficulty in order to disohargo coal and Uke in cemont cargo. The number of men employed at the works ranges from 100 to 120. Work ii continuous in- shifts of eight hours. HIGH-QUALITY ARTICLE. It is interesting to learn that since the company commenced to put their cement on tho market they have received orders in the various centres throughout New Zealand, from Duuodin to Auckland, aud along tho West Coast from New Plymouth to Grcymouth, and also from various liew Zealand public bodies, and the greatest satisfaction'has been expressed regarding the quality of tho material, and its suitability for building purposes. Tho tost* to which it has been put in variouß directions by local bodies and contractors are such as to convince any practical man that the golden Bay article is a true Portland cement, and equal, if not superior, to any similar material on the market. GENERAL. In addition to the buildings, tho wharf U lit «t night rime by electricity of considerable candle-power, and at night tie flashing lights are of considerable use to mariners trading along the coast. The whole of the work, in connection with the manufacture of the cement appeared to be of a wry hiffh' order by both workmen and staff, And tho works i themselves had tho trim appearance usuallv associated with intelligence, enterprise, find quick dispatch. In addition to p,ws«*ng a very valuable property and a first-class Article, the company appears to l)e doubly fortunate in the quality «f ids Muff and workmen generally.