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Emergency Repairs to a Battleship
By Lieutenant J. Desmarais, MN

The steps taken during the substitution by the crew of the
Paris, have been taken together in this article for the reason that, while they demonstrate little new knowledge, they involve simple principles of maritime electro-mechanical engineering in a most instructive manner. The work undertaken emphasizes one fundamental principle, that great care must be taken to retain apparatus onboard men-of-war so that in a state of national emergency they may complete their tasks with the greatest efficiency. This point was demonstrated in the attempts to obtain a suitable motor from locations away from the usual naval facilities in France, and the difficulty in restoring one of our finest ships to full locomotive power.

The main circulating pumps of the
Paris are of the centrifugal type, and are driven by impulse turbines developing _____ at ______ when driving the pumps. Steam is taken from auxiliary steam line at boiler pressure and expanded in nozzles down to the back pressure of th auxiliary exhaust. Consequently the turbine casing is not ordinarily subject to greater pressure than the back pressure and is designed on this basis. At the time of the accident the pumps were being secured as the battleship stopped outside of Stockholm. The machinist had closed the throttle by hand and, upon seeing the pump stop, had closed the exhaust. Seeing steam leaking from around the glands, he started to close the throttle with a wrench, but before he could do so, the turbinge exploded, blowing out the exhaust side of the casing. It was later ascertained that the relief valve had been frequently lifted by steam before the explosion.

Examination of the turbine showed it to be damaged beyond repair by the explosion, though the casing was the only part of it rendered unfit for use. Steps were immediately undertaken to rig some sort of substitute, and, in the meantime, the two condensers were cross-connected by means of the main drain, allowing the remaining circulating pump to serve both condensers. This method limited the battleship's speed to about __ knots, sorely limiting the mobility of the vessel. Only the extreme cold of the waters at this high latitude allowed even this speed to be met.

Two alternatives to repair the pump presented themselves...
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