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78 electric drive has been adopted on the above steamers may be mentioned, from motor-driven hair brushes, meat roasters, plate washers, potato peel- ers, etc, to the 16 50-horsepower fans for forced draft; fans again for ventilating the-fan rooms, fans for ventilating machinery spaces and Thermo tanks for ventilating the ship generally. in the engine rooms motors are used for driving the lifting. ' gear for overhauling tne turbines, for turning gear for control.ing the ex- haust valves, which are 75 in. in di- ameter, and for centrifugal pumps for drawing off surplus water from the condensers. Motors are a:so used for two passenger lifts, baggage lifts, two store hoists, two pantry hoists, two mail hoists, four 12-cwt. deck cranes, four boat winches; altogether about 2,000 horsepower in motcrs are in- stalled. It is often said that electric ihotors are unsuited to the rough usage ob- taining in ships, but to those who still hold such opinions the above instal- lation is in itself a sufficient contra- diction, the more so as in every in- stance most satisfactory results have been obtained, results which are in great measure due to the. improve- ments made in recent years, both. in design and manufacture of direct-cur- rent motors. Electric Winches Considered. Reverting to the ordinary ship's equipment, the winches come next for consideration; this is a subject which has often been discussed by superintendent engineers, and so far as the author is aware, the principal objection is the first cost--in this re- spect it would be rather interesting to know what was the cost of an ordinary ship's steam winch when they were first installed--or say 30 years ago. The author's opinion is that if electric winches were in de- mand to the same extent as steam winches, the cost of installing them would not be much greater, if any, taking into consideration the steam and exhaust pipes, valves, etc., while mere ¢an be no doubt as: to the higher efficiency, less cost for work- ing and less cost in upkeep, whilst the advantage of quieter running would be appreciated, especially on a passenger steamer. The construc- tion of a: suitable winch offers no difficulties, the motors can be made sufficiently watertight to withstand the bad weather and boatswain's hose, at the same time ample ventilation can be provided by means of inlet and outlet pipes, with fin blades fitted THE Marine REVIEW and this is now a in fully en- to the armature, very common practice closed motors. * It may be said that winches are particularly subject to rough usage and worked by unskilled men, but electrically driven pile drivers worked by navvies have been installed at the Hull Joint dock for over 12 months, working in the open without any pro- tection from the weather and fixed on gantries in the sea, as well as in the bottom of the new dock. These motors work at a pressure of over 500 volts, and are said to be in every way satisfactory; the advantages over steam drive are obvious, especially in a case where they are working actually at sea, or where coal would have to be carried any distance. The ordinary ship's winch is invariably fitted with a double gear, center bar- rel and warping' ends, but in some cases the warping ends are used for discharging cargo with a loose fall, May, 1909 The generating plant which would be necessary to provide for a vegge] electrically equipped requires very careful consideration, so that the cap- ital outlay may not be excessive ow- ing to too much power being in stalled; at the same time it must be sufficient for all requirements and emergencies. The first point to con- sider is the ordinary cGemand when the ship is at sea under normal con- ditions, including the lighting, In the 'daytime all the lighis would not be required, but many of the auxiliar- ies, such as~ sanitary pumps, fresh water pumps, etc., would be. required more in the daytime than at night, which would help to balance the load. If the number of lights is taken at 600, in the ship under consideration, 75 per cent would be a fair amount to take as a working load. The aux- iliaries taking a constant load would be feed pump, main circuating pumps, bilge pump, steering gear; the other 'should be alike the winch running in one. direction, auxiliaries would be more or less in- while in other cases the center barrel termittent. The following will show is used with a fixed fall and the the approximate power required to winch reversed; for electric winches' be installed: ; Be ver 2 maim teed piinps, cach. 6,400 galls. per hour (35-1. Pi each)... oo. co ci eee 70 1 auxiliary pump 6,300 galls. per hour 1 main circulating pump 230,000 galls. per hour 1 bilge pump 6,500 galls. per hour 1 wash deck pump 2,000 galls. per hour 1 sanitary pump 9,000 galls. per hour 1 fresh water pump 2,000 galls. per hour 1 ballast pump 33,600 galls. per hour I Stecrings Sea. a ae, os oe Se ee fee eee ee ey cos ole os ccs pees Cotes east Ott ro ov oc ccc ee cscsunuue ee WIE i ee oe ek cb vec cdo c hn vee hres Ue Te Cm CU oo hic ny ce CS ewe cw eccb en cu 0s cou ee he Wireless (savior be tl be Cac) ec ccc cc wenn cee the center barrel could be done away with and the shaft and bearings made strong enough to allow of either end drum being used with a fixed or loose fall, the gear heavy enough to take the full load, and 'with the speed reg- aiation of the motor taking the plact of a double gear, such a winch would be quite capable of dealing with all ordinary freight.. Where heavy and bulky pieces have to be handled, a special winch would be fitted at the main hatch where such pieces are usually stowed. It does not appear necessary or advisable that all winches irrespective of the class of cargo they have to handle. The type of winch fitted on cross channel steamers of tne Great West- ern railway, has controllers fitted be- low the deck with the spindle coming up through a cast iron column bolted to the deck and operated by means of a handwheel. The drums are driy- en by ,means of machine-cut gearing working in an oil bath. worm say 320 K. W., add 600 lights, say 36 K. W., making a total of 356 K. W. actually required to work the full equipment at one time, but the winch- es and windlass are not working at sea. The main feed pumps and steef- ing gear are not working at the same time as the winches, whilst the turn- ing gear, ash hoist and other pumps are intermittent. It would be quite safe to. install a generating plant for say, 225 K. W., divided into three 75-K. W. sets, each capable of with- standing an overload of 25 per cent for one hour after a full load test of six hours with normal temperature rise, this would give a margin of 25 per cent, or about 270 K. W. On this basis two dynamos would be ample to deal with the sea load leaving one as a standby, and it will be found that the two generators would be ample to cope with the work when in port. The space 0¢- cupied by the generators would not be excessive if they were of high-