WAIPORI POWER STATION.

Otago Daily Times, Issue 21198, 2 December 1930, Page 4

WAIPORI POWER STATION.

LOCALLY-MANUFACTURED ' MACHINERY. : Two hydraulically-operated sliiiCe valves, made and ’ designed by Messrs A. and T. Burt, Ltd., Dunedin, have been completed by the’ firm as portion' of. an-order forsix valves of the kind for the Waipdri works to replace Johnson Boving values at present in use. The valves are designed to withstand a working pressure of 3151 b to the square inch-and a test pressure of , 4701 b to the square inch.' The two in "the workshops have now been tested and passed by the corporation officials.

. When in position the valves (eight feet high) will he operated by means of. water pressure from the pipe-line, the water entering the hydraulic cylinder at the top of the valve casing. Water pressure will lift .the valve or close it as desired and, to enable this'to be done, a special regulating valve is .fitted to the hydraulic cylinder. , Four-inch - diameter by-pass valves are attached, go that when pp-uing the main valve, the pressure may be relieved from the tongue, making it ■ easier to lift. Indicator gear is. fitted to the cylinder to enable the power house operators to know exactly the extent to which the valve is open. The weight of the valves is approximately three tons and a-half each. This is the .first time that work of this nature has been carried out in New. Zealand. In tendering for the work: four months ago, "Burt’s had - to'.compete against the imported article, and it is a credit, to the 1 firm and its workmen that the corporation, after a rigid test, has accepted the two completed valves for the work for which they were designed. The other four are well under way in the workshops in Cumberland street. - ,