The International Steam Pages

Steam-Turbine-Electric locomotives

Harry Valentine, Transportation Researcher. writes (2nd March 2001):

"I've received some e-mail communication from people who read your website ..... and advised me that steam-turbine-electric locomotives are unworkable: They did me the courtesy of pointing out the technical and economic failures of the American steam-turbine-electrics built by GE & also by Baldwin-Westinghouse.

1)Efficiency:the old s-t-e locos had single main turbines, mounted lengthwise (susceptible to fore-aft shocks when coupling in marshalling yards).

Ans: The quad turbine system operates at maximum efficiency at 15-equal-step power-settings. The turbines can be mounted transversely .... due to their smaller size, thus being less susceptible to damage from fore-aft shock loads. Some of the turbines could also be the compact, radial flow layout.

2)Coal dust and dripping water used to foul DC electrical gear, including the main generator as well as the traction motors (the commutators were vulnerable).

Ans: Modern locos use 3-phase AC traction motors .... the AC alternators use slip rings, not commutators. Modern electrical generation and traction gear is far better able to operate in conditions where they're exposed to waste and coal dust. Liquid (oil) cooled (and sealed) alternators do exist at the present day.

3)Electrical control gear will be fouled by coal dust.

Ans: Modern air filters are a vast improvement over the non-existent air filters on the old American s-t-e locos. Several new generation air filters are re-useable, requiring a rinse with water every few months.

4)Steam turbine electric locomotives are not feasible.

Ans: Modern s-t-e locos can realise cost effectiveness at very high and extreme settings power ..... such as what would be required in heavy-haul operations.

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Rob Dickinson