MARINE DIESEL ENGINES

Otago Daily Times, Issue 22212, 15 March 1934, Page 16

MARINE DIESEL ENGINES

NORTHERNER'S INVENTION VICKERS BUY BRITISH RIGHTS A device which is expected to make a great improvement in the efficiency of large marine Diesel engines has been invented by a resident of Kohukohu, Mr H. D. Dall, who has already sold the British and Canadian rights' to the Vickers organisation for £SOOO, phis a substantial- royalty. Mr Dall (says a correspondent of the New Zealand Herald) is an engineer of long experience in Britain and other parts of the world. His device, described as a pulsator valve, dispenses with the need for extremely high-pres-sure fuel injection in large Diesel engines. It is claimed to reduce the fuel consumption by 10 per cent., and the first cost of the engines by from 8 per cent, to 12 per cent. On a 10,000 h.p. Diesel ship, this is equivalent to a saving of from £6OOO to £BOOO on first cost of machinery, and from £25 to £3O a day on the cost of fuel. In the ordinary Diesel engine the fuel is injected by an air blast at a pressure of 10001 b to 12001 b to the square inch, through an extremely small aperture of .0025 in to .0040 in in diameter. This was liable to cause trouble by becoming choked. Moreover, the protracted period on injection rendered it impossible to make engines of more than 100 h.p. to 120 h.p. per cylinder. Mr Dall's pulsator valve, which is inserted in the pipe conveying fuel to the injector, is claimed to do away with these drawbacks. It enables the use of an' aperture three-sixteenth 9 of an inch or more in diameter.

The British and Canadian rights have been sold to Vickers, Ltd., the wsllknown British shipbuilding firm, for £SOOO, plus a royalty of 2s 6d a h.p. on all engines constructed in Britain and Canada. Negotiations havq been opened with a leading firm of shipbuilders in Italy, which has paid a deposit of £l5O for a 60 days' option to purchase the Italian rights for a sum of £SOOO.

Mr Dall states that the invention is so important and necessary that several ether countries are expected to apply for rights. If it conies into general use his returns will be very large indeed. He estimates that on two ships now building for Canadian owners tin royalty payment, if the device were incorporated, would be £2500. The discovery, according to Mr Dall, was made in quite a simple way about 15 years ago. At that time he had insufficient capital to patent the idea, but about three years ago he developed the patent, and at a cost of £(500 had it protected in every country except Russia.

Mr Dall served in an engineering capacity with the British forces during the Great War, and subsequently came to New Zealand as a representative of a company interested in the marketing of Diesel engines. He retired a few years ago and took over the management of the Kohukohu Hotel, but he has retained his keen interest in all matters appertaining to Diesel engine developments.