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ROTARY FIRE PUMPS.
This style of fire pump is not recommended, as it is subject to excessive rusting, being generally located in damp or wet places, and is of such construction that deterioration is practically rapid; is usually connected up with the main shaft from the water wheel and cannot be operated independent of the main shafting and counter shafting of the plant, and is more liable to breakage than a steam pump.
The pump should be located in a place easy of access and not liable to be cut off in case of a fire in any part of the plant.
Spur or cog gearing should not be used for operating the pump.
Belts should not be used tor operating the pump, as the great liability of the total incapacitation of the pump through the burning of the belt is presented, and, also, the belt is apt to so deteriorate as to be of practically little service in operating the pump to its fullest capacity.
Friction gearings should be used for coupling.
A separate water wheel is advisable under all circumstances for the propulsion of the pump.
The wheel or mechanism for throwing in the gearing should be located in a protected place, easy of access, and where there is the least liability of its being cut off in case of fire.
Safety or relief valve, of the Ashton or Crosby, or some other equally good pattern, should be attached to the pump.
A pressure gauge should be attached to. the pump.
Suction.—Pump to be so located in respect to its water supply that at no time shall it have a lift of over 10 feet during 60 minutes' discharge at rated capacity.—(National Fire Protection Association Standard.)
Oil.—A sufficient quantity of special quality oil should be kept at the pump for the proper lubrication of its parts.
A clutch coupling should be so located that, in case of the need of operating the fire pump, the entire shafting of the plant can be thrown out and the full capacity of the water wheel or engine be used for the operation of the pump.
In operating the pump, care must be taken that the friction clutch is thrown in tightly, so that the full power available will be realized, and also in order that the friction wheel will not heat up on account of slippage.
"The location of these pumps is usually in a wheel pit in an outof-the-way place, subject to many variations of conditions, alternating dry and wet, hot and cold, where all parts rapidly accumulate rust. The operation involves the most dangerous conditions in mechanics. Starting a rusty device, all cast iron, perhaps in a temperature below freezing, after long disuse, putting it immediately under high velocity and excessive journal pressure invites a disaster. We rarely find them properly supplied with the right kind and quantity of lubricant, and we feel it only necessary to report that just as few of these pumps as possible should be used; that they should be located to the best advantage, as suggested by the underwriters where they have the opportunity, and that they should be provided with all the safeguards known to be needed, namely:
"First—Say a barrel of well-chosen lubricant.
"Second—A check valve to guard against the loss of water from other sources, should the pump go to pieces.
"Third—A pop or spring relief valve, to avoid dangerous pressure.
"Fourth—Securely set upon reliable foundations, to prevent \ibration or strain, preferably to be driven by separate wheel.
"Fifth—If geared to the general power, all other machinery should be arranged to throw out by friction clutch at or near the pump.
"Sixth—Friction gears, or if possible to find a reliable clutch, should be the means of attaching power to the pump; both the pump and the gearing to be so securely fastened that they cannot shift when the gears or clutch are thrown in."—(From report of Committee on Rotary Pumps, as adopted by the National Fire Protection Association, at its fifth annual meeting.)
Table Of Rotary Pumps—Continued.
Two hundred and fifty revolutions per minute is the esual speed for fire service.
H.-P. Required For Operating Rotary Pumps.
RESERVOIRS AND OTHER SOURCES OF WATER SUPPLY.
The supply of water for the fire pump is dependent upon the locality, the natural and artificial water courses and supplies, the "lay" of the land and the size of the supply required.
Where there is a running stream of adequate proportion and constancy the supply is easily obtained, but where the stream is not constant in its supply, or where wells have to be depended upon, the question of supply becomes more of a problem in localities especially subject to dry seasons.
Any running stream in which there is much solid matter or much matter in solution should have a settling basin or reservoir in which the solids and matters in solution can precipitate before the water is used by the pump.
Where the supply to a reservoir must be pumped from a distance to the reservoir, a double cr triple plunger pump, operated by an electric motor, will be found a most excellent method, as by this system the pump can be set running from the dynamo room and does not need a man to go to it every time that it is run, hence is more certain to be in service when needed.
All water taken from ponds or running streams should be taken from cribs provided with strainers and mud-catch boxes.
During the Fall streams bring down much in the way of leaves, small sticks and other refuse, and these are liable to hold against the strainers; hence it is that the intakes should be examined periodically, especially in the Fall, so that the capacity of the intake may not be diminished.
The flow of water in head and tail races is usually swift, hence in order to get a good intake into a pump suction pipe, the footvalve should not be too close to the surface.
RESERVOIRS.—An all-earth reservoir is not to be recommended. Defects: During the falling of rain the water will wear away the sides ot the embankment and carry much mud into ihe