THE MECHANICAL ASPECT

Taranaki Daily News, 9 May 1930, Page 14

THE MECHANICAL ASPECT

MODERN DRILLING PLANT NEW PRECEDENT AT OMATA. DIFFICULTIES ANTICIPATED./ According to Mr. D. J. Tynan,, drill manager for Coal, Oil (N.Z.) Ltd., there has been assembled at Omata the finest machinery for the. purpose which it has been possible to purchase. It. has come form half a dozen manufacturers, all. of whom have specialised for years in the production of plant designed to meet every contingency which the experience of the oil driller could suggest. Mr. Tynan is an Australian, whose experience with the diamond drill'began in 1899 on the Western Australian goldfields. A drilling crew in charge of Mr. David Thompson came from Australia to New Zealand in 1903, Mr. Tynan being among them, and work was undertaken at the Woodstock mine, Karangahake, the Golden Cross, Whitekauri, Waihi, and on the Thames goldfield. Subsequently Mr. Tynan returned to Australia and had further extensive experience in. drilling. Entering into business on his own account, in 1907 with a partner, he started a drilling company .working in Montana, 1 United States. Subsequently he went- to Mexico, and in 1921 he entered the oil drilling industry, and became a drilling superintendent on the Tampico oil-field. •This is one of the comparatively shall.|h oil areas, where the deepest well is about 3,5-00 feet though most of the oil is obtained from between 1,800 and 2,200 feet. It may be remarked in passing that there is oil production in the United States from wells of 8,500 feet, and that the Omata drilling plant is capable of going down to .that depth if necessary. AU wells are not “gushers.”. In Mr. Tynan’s experience the drillers tapped oil strata which produced as low as 47. barrels per day, and at Tampico many wells gave a production of 15 barrels. •Where the oil is found in association with sandstone it usually exhausts the initial pressure which brings the flow to the surface and then production continues by pumping. Flow continues for some time under gas pressure, but when that ceases there is a considerable yield left which can 'be extracted with the pumps. The New Plymouth field is sandstone, therefore one may expect that if the company taps a good oil deposit, it may ultimately have to keep up the yield, by pumping. ’

DEVELOPMENT OF DRILLING

The methods followed by oil drillers in Mexico ami the United States have ibecn practically standardised as .the result of successful experience. Equipment is also very similar with all modern drilling plants, for the tremendous amount of this work has created a big engineering industry catering wholly for drilling requirements. “We are profiting at Omata from many costly failure.",” remarked Mr. I'ynau. “We hear

nothing of the failures by the wayside, but we see only the perfected plant which' has resulted from that experience, and here we have'the best which could be selected. During the last five years there has been a wonderful change in drilling methods, which have been practically revolutionised. All this has made for quicker drilling, greater certainty, more accuracy, and greater ease in handling the heavy plant necessary to reach great depths.”. “Every hole presents its own pror blems,” said Mr. Tynan when attention was directed to the large stock of equipment and spares provided at Omata. “All this is needed for eventualities,” he explained, “for you could not rely on any one set of tools to handle the complete job, as you do not know exactly what you will encounter beneath the surface. You look for caving in most wells, and that is part of the regular routine. Our large stock is necessary in order to ensure that now we have started drilling, we can get ahead, despite all the difficulties, and that we will not have to wait for the importation of the specialised equipment required for the work. We have anticipated the difficulties, and expect that the equipment ordered will be quite adequate to deal with them.’’ MODERN DRILLING PLANT. The dominating feature of the landscape a couple of miles south of Moturoa is the lofty derrick over the site of Coal, Oil (N.Z.) Ltd’s. No. 1 Omata bore. This steel structure, characteristic of those on the great oil-fields, is 122 feet in height, and stands 160 feet above sea-level. There is an important reason for having the loftiest oil derrick ever erected in the Dominion, and that became evident when the drill stem was extracted from the hole for examination of the drilling bit after it had penetrated about 100 feet and reached a change in strata. The drill stems are of various averaging about 20 feet, and they are screwed end-to-end. To lift one length of a hundred feet meant a simple operation, involving the breaking of the stem only once, but if the hole had been down a thousand

feet or so, ten breaks in the stem would have been needed to get the whole to the surface. With a shorter derrick, the breaks would have to be made every 20 feet or so, and the job of extraction would be endless.

The drilling stem is hollow, and Sullivan F.K. diamond drill, designed after long experience to carry out the largest drilling jobs with the utmost expedition. The drill is attached to a rotary stem, and when at work is spun round by steam power at a rapid rate. The weight of the drill and stem,, plus the rotary impulse would probably provide a very effective drilling method, but in the Sullivan machine, there is another important feature making for positive action. .This is. the hydraulic ram, which is attached to the drill stem, and as the drill , rotates . deep down in the earth, forces it steadily into the strata. One could hardly im--agine any obstruction which would fail to disintegrate under such a combination of powerful and positive forces. The drill stem is hollow, and through its core is forced a mixture of thin mud, driven right to the point, of the drill by a powerful pump, built by a firm of specialists in oil-produc-tion machinery who have appropriately named it “The Mud Hog.” This stream of mud flushes the bit and, rising to the top of the hole, carries with it the loosened material, which is regularly and very closely examined by' the com--1 pany’s geologist. .

AN OIL-PRODUCTION HOLE.

Coal, Oil . (NIZ.) ; Ltd., which lias set so many new precedents in its exploration for oil in New. Zealand, lias created another by. drilling a ' hole 25 inches in diameter, the usual size for oil production, as distinct from the smaller diameter required for simple exploration. Its equipment includes a large variety of drilling tools, or- bits, including the Hughes Simplex Roller Bit, an impressive -tool weighing nearly 2 tons. This solidly designed drilling: tool has two large cutting rollers at the end, and also side cutters for trimming the hole. It is capable of easily working its way through the hardest formation likely to be encountered at Omata. Now that drilling is under way it will <r o the whole round of the clock each working day J as three shifts have been organised. In 'addition to the diilling manager with his wide experience m.s a specialist in the work on oil-fields, there are two drillers in charge of.shifts who came from the. Tampico pil-field and are thoroughly well up in this work. The remaining staff includes a number of New Zealanders, who are rapidly being trained to manipulate the machinery designed for their task of drilling down to the point where, in the confident opinion of the company s scientific advisers, oil will be found in commercial quantities.