IMPORTANT MINING EVENT

Hokitika Guardian, 25 March 1931, Page 2

IMPORTANT MINING EVENT

launching rimu dredge NO. 2. TO DAY’S FUNCTION

The town and district are greatly interested in the launching of Rimu Dredge No. 2, at Rimu Flat. The occasion marks an important mining event, in that after ten years steady operations, it has been found necessary to renew the hull of the dredge and most of the machinery, -with a large hull, substituting steel for timber and installing, more - powerful machinery. This is a practical indication of success and progress, and it is a matter for congratulation all round that circumstances require suen s

move, and conditions justify It. ■. It was in April of 1921, when the 'first pontoon was launched, Particulars of the event were published .in yesterday's issue, and made interest- " ing reading in the light of the happen•;.n<rs over the years between. Date in 1921 the large dredge was in opera...tjon, and created great interest ror . the mining world af large, The dredge was designed bn the lines of similar machines in nse in America,' and the years of faithful service prove how ■Veil the dredge was adapted to re. qmrements. In working the Heavy machinery in the heavy ground, there |VttS of course a very severe strain on i-ntho wooden hull, It'ls not too much ■:> say that the .management has lm a

Iffln anxious time of. late attending to , th« hull, In times past the interior ’ was strengthened with • jjeavy ..ban k 4 timber, as well as partitioned provide jug water tight compartments tg ensure greater buoyancy. But themphjq- - ery kept pounding away, and when * the strain began to tell seriously, it was evident replacement was essential 'Hence the new bull lias materialised, " and with much of the top hamper : aboard was floated into the dam this afternoon. The Company with commendable enterprise, specified for a larger and stronger dredge in every way, for there is still a large area of Rimu Flat to be worked. The Hansford Mills Construction Coy. secured the contract, and the dredge was built and assembled first at the works, in Wellington, and then brought to the site at South Hokitika, where the work of construction has been in hand under Mr A. McLaren.

THE NEW PONTOON. The following is a brief general description of th« new steel dredge which was launched by the Rimu Gold Dredging Company this afternoon. The completed dredge structure is entrioly of steel, there being no timber other than such as may be used for walks on the decks and stacker ladder. Tho structure when completed will contain a total of 1,649,fi011h of steel, al lof which was ' purchafted and shipped from England, and fabricated at ’WHUnszton. Tim structure diywes itself into two major parts, namely, the pontoon or hull, and the super-

structure and housing. The pontoon portion is built, in poeordanoe with general scow design, except thpt nil members are far more substantial in section, and placed at closer' intervals than is customary. The pontoon has an overall length of 118 feet, with a breadth of 56 feet, and a depth of 11 feet. The forward portion is divided into two pontoons between which the digging ladder operates, The pontoon is divided into 18 water-tight compartments, each compartment being separated by water-tight bulkheads. Access to the compartment is through hatchways in the main deck. Eaoh transverse bulkhead is built as a selfcontained plate gtrder beam, and act as stiffeners for the structure. The construction behind the digging spuds is extremely strong, and so designed as to distribute the shocks, incident to digging surges, throughout the entire pontoon. The .superstructure comprises all those ortions of the dredge structure above the main deck of the pointooh, A nd divides itself into the main structural members, and th e general housing, walls, machinery supports, and so forth. The main structural members consist of the longitudinal truss-

es and n transverse truss across the bow pontoons. There are two main longitudinal trusses, connected with each other by plates and diagonal bracing the whole forming a beam the carrying capacity of whioh is many times the weight of the entire hull. The main transverse truss acts as n stiffener across the bow pontoons, and helps to prevent sag or distortion of the structure along its longitudinal axis. The main framing has a height of 25 (feet above the main deckAt the front end of the pontoon is the bow gantry, built of most substantial steel sections and connected directly with the main longitudinal trusses, this has a height of 46feet 9£ inches above the main deck. The bow gantry carries the weight- of the digging ladder and buckets. At the after end is the stern gantry having n height of approximately 70 feet above the main deck. This also is conneced with the main longitudinal truss, and carries the stacking ladder. The dredge when launched will have a total weight of 942,000 lbs., and will draw approximately 3 feet of water. When fully completed and in working order the- dredge will draw an average of feet of water. The dredge will ho equipped with four pumps, throwin* a combined stream of 11,100 gallons per minute. All machinery is electrically operated, the mam or digging motor being of 320 horse power,

the high pressure pumps 125 h.p. each When ready for operation the dredge will have a total connected load in excess of 800 h.p. The new dredge will have an average digging capacity of 200,000 cubic yards per month, or approximately 30,000 yards per month in excess of the present dredge. As now erected, the ladder is capable of digging to 49 feet below water level, arid arrangements have been made for increasing this to 70 feet below water at a future date. ~* The design of all machinery and working parts combines the-latest in dredging practice, together with innovations devised from past experience in this locality. When in operation the working costs per cubic yard should show a substantial decrease, thereby .permitting of the treatment of lower grade gravels which will prolong the lilt* of the operation.

WORK AHEAD. It is an impressive sight to drive over the boulder road, and view the area which had been worked already. Originally the claim was about 1200 acres, but a substantial portion has been worked. It is estimated there are still 20 years’ work for the dredge ahead. The ground is thoroughly treated, and to do that, all remnants of the forest which once grew on the Flat has to be removed, The work is well organised, First to the prospectors; then the hush clearers, and finally comes the dredge. Over the ten years, work has never slackened. With the thoroughness peculiar -to the general operations of the Company, the work is kept well m hand and triere is np letting Mr.

W. J. Radford is tlm present BORG dent Manager, and Mr Lewis (who has been riei’ e since thp incept-imr flf the Company) is the PredgemasterIt speaks well for the careful management of tba leading officials that the dredge has been able to operate so steadily and so consistently over so many years of heavy work. The dredge lias been able to absorb a large amount ol labour of all kinds. With three dredging shifts going practically continuously, a number of dredge hands' are required. In addition there are those, engaged in prospecting and : bush clearing. Nor does this exhaust the roll of employees. Men ar eengaged in the workshops and at the sawmill, while there is also an office staff. Altogether the industry lias been a large employer of labour,. maintaining a considerable pay roll over the years o operation, while in addition, it is noticeable that the

Company retnins its workmen over many years, indicating the happiest of relations between employer and employee; The Company has always been most obliging in permitting tourists and sightseers'generally to inspect the dredge, at work. Actually, the working of the dredge has become quite a feature for visitors to the district, and Very few miss the opportunity of seeing the dredge in action, In thnt way it has been an asset to the district ns a whole, find has become quite an established attraction,

TODAY'S GEREMPNIAL The launch this, .afternoon is timed for 2 o’clock. Workmen have been busy for some days past preparing for the event. Five “ways” in all have been placed,in portion awhr the leviathan pontoon. Their appearance suggest ample strength to !><ar th® burden, for they ore built up of gieat baulks of timber, The final preparations for the launching were advanced rapidly yesterday, and this r- i ruing the last touches were given, so that everything will b e in complete order, according to schedule, by noonThis is an excellent achievement in the face of all the difficulties which have bad to be overcome, but the large staff of workmen has worked exceedingly well, and at every stage the work has been advanced as rapidly as possible, Immediately after the launching their will be a civic function where at the Mayor (Mr G, A. Perry) on behalf of the citizens will present an address to the officials of the Company, expressing appreciation of the many courtesies extended by the management to the borough and district, and wishing the extended venture of the Company success.

THE CIVIC ADDRESS.

The following is the text of the address presented to the Management by the Mayor this afternoon:— The Chairman, Directors and Manager of the Rimu Gold Dredging Coy. Ltd., and Ivanieri Electric Ltd.

Sir and Gentlemen: —On behalf ol the citizens of this district we congratulate you on the launching of tbe new dredge. Your transactions Here have always been conducted with the utmost fairness and consideration and this has given you a place in the esteem and respect of this community second to none. We also wish to express our appreciation of your public spirit. Any function or movement of a public nature has always received a generous response from you and you have assisted with a goodwill and kindness which the citizens very gratefully remember. Mr Cranston, your .chief engineer and managing director, has been associated wfth the enterprise from the beginning and we fee] that we can, without impropriety, make a special mention of his name in connection with the above. We wish you the success which we feel you deserve and the greater the success the greater will he our pleasure. Sir and gentlemen, on behalf of t]ie various local authorities of this 'district we beg to subscribe ourselves,

Geo. A. Perry, Mayor of Hokitika, Wjiiit Searkk Chairman West loud County Council, John J. Breeze, Chairman Wie-stland Hospital Board, Malcolm 11. Houston, Chairman Hokitika Harbour Board, E. Teiehelniann, Chairman Westland Progress League, James A. Murdoch, Chairman High School Board of Governors, AY. J. Butler, Chairman Westland Electric Power Board. Hokitika, March 25th., 1931.

To-night there will lie a public hall accorded to the Company’s officers ftud management at th<> Soldiers’ Hall. This promises to be a festive function. The large hall has been decorated specially for the occasion, and every preparation made for a gala night. There will he many visitors present from all parts of the district and the occasion should prove to be one ot the most important public functions of the vear.