The New Zealand Railways Magazine, Volume 7, Issue 7 (December 1, 1932)
Almost Doubled Power
Almost Doubled Power.
With “booster” in operation the power of the locomotive will be approximately 85 per cent, greater than the power of the “Ab” class locomotive. The “booster” referred to is a complete two-cylinder engine which is supported on the rear of the trailing bogie framing and which, through gearing, develops power to the trailing bogie wheels. When this “booster” engine is brought into operation, these wheels, which normally are “carrying wheels,” do useful work in page 54 propelling the engine, or, in other words, are temporarily converted into an additional pair of driving wheels. The “booster” engine is directly controlled by the enginedriver, but, as speed increases and the enginedriver shortens the “cut off” of the main valves, the “booster” engine automatically “cuts out” at a predetermined speed point.
It will be seen from these figures that a big step forward is being undertaken by the railways and, as the job is completed, the withdrawal of obsolete type engines will result in greater working efficiency with its resultant lowering of cost per unit of work done.
The work on the first group of “K” locomotives, as the new type is called, is well under way, the major portion of the work being undertaken at Hutt Shops, whilst Hillside (Dunedin) Shops are assisting on certain details. As far as is possible, no manufactured parts are being imported, as it is the Department's desire to carry out the maximum amount of the work involved locally.
Designed And Manufactured In New Zealand;
(Rly. Publicity photo.)
Locomotive “K” 900 recently completed at the Hutt Valley Workshops. Wellington. The following are the chief particulars of the locomotive:—Type, 4-8-4 with double bogie tender; water capacity, 5,000 gallons; coal capacity, 7 ½ tons: total weight in wortang order (exclusive of “booster”), 136 tons; total weight in working order (including “booster”), 139 tons; tractive force, 30,815lb.; tractive force, including “booster,” 37,285lb.