Motor Operating Pump in Sprinkler System.

In manufacturing plants where a fire is liable to be especially disastrous to both life and property, fire protection is of great importance, not only to save direct fire loss, but also in some cases to comply with regulations of municipalities and in others to reduce the cost of insurance. Plants in which clothing is manufactured belong to this class, and the more progressive manufacturers are not slow to employ the most modern systems of fire protection known. Hart, Shaffner & Marx, the well-known Chicago clothing manufacturers, won a large building which is protected by an automobile sprinkling system of a very modern and reliable type. The sprinkling system extends throughout the building. Pressure in the pipes is maintained by a 2,000 gallon compression surge tank, which is normally half full of air at 150 lbs. pressure and acts as a cushion for the system. Water is kept in the surge tank under a pressure of not less than 140 lbs. by a motor operated pump, shown in the accompanying illustration. The pump’s capacity is 1,000 gallons per minute at 150 lbs. per square inch pressure in excess of the supply pressure in the city main which is about 25 lbs. The motor starts the pump automatically when the pressure drops to 140 Ihs. The air cushion tends to compensate for light leakage, so that practically constant pressure is maintained; frequent starting of the motor to replace small losses is therefore avoided. Under present conditions the outfit operates once in about every ten days and runs but a few seconds until full pressure is restored in the tank. The entire installation is provided with telegraphic indicators. One shows the exact height of the water below the cut-in pressure of the pump; another level in the air cushion tank; another whether the pressure on any part of the system drops tells whether the voltage is cut off from the control panel outside or at the switchboard. All main valves are provided with alarms which sound when the valves are closed. The pump is of the horizontal three-stage pattern, built by the Jeanesville Iron Works Company. Besides keeping up the pressure in the surge tank, the pump feeds a standpipe service, so that hose connections may be made at several points on each floor in case of fire. A gravity roof tank, of 40,000 gallons capacity is used as an auxiliary to the pump in feeding the sprinklers should anything happen to the motor, pump or control. This roof tank, however, is not connected to the standpipe system. The latter has to rely on regular steam fire engines in case of failure of the electric pump. The pump is so constructed that it is impossible to overload the motor in case of excessive water flow such as would he occasioned by the bursting of one or more hose lines. The pump casting is spit horizontally and the suction and discharge connections are both in the lower half; thus the upper half may be removed for inspection and repair without disturbing the main Connections, in addition to the two main hearings o fthe pump a marine type thrust bearing is provided at the end of the shaft for the purpose of taking up the end thrust. This bearing is supplied with forced lubrication by means of a scoop shaped oil thrower. The thrust bearing is also water jacketed, the water being taken from a connection made to the third stage of the pump, and its flow automatically regulated. The illustration also shows the hose connections provided on the discharge pipe for use in case of fire in the basement. The motor is built in acBoard of Fire Underwriters, which specify the following: The motor must be entirely enclosed and provided with a ventilating blower on the end of the shaft. The air intake must lead to an adjoining room so as to insure cool air being furnished to the motor. It must also be water proof. The air outlet pipe must be turned down so as to prevent falling water from entering the motor casing. The motor frame must be water proof up to its center line. All covers provided with rubber gaskets to keep out falling or other accidental flow of water in the engine room. The leads must be brought out above the center line so that they will not be damaged by water until it gets up to the shaft. With continuous operation at full load the rise of temperature in the motor must not exceed 40 degrees. The motor is of Westinghouse make, direct current. 150 h. p., 1,400 R.M.P. volt, and designed especially for service of this kind. The control which was furnished by the Cutler Hammer Company, is automatic, although it is arranged for hand operation in case of emergency. The installation described reduced the insurance premium on the building approximately onehalf.

In manufacturing plants where a fire is liable to be especially disastrous to both life and property, fire protection is of great importance, not only to save direct fire loss, but also in some cases to comply with regulations of municipalities and in others to reduce the cost of insurance. Plants in which clothing is manufactured belong to this class, and the more progressive manufacturers are not slow to employ the most modern systems of fire protection known. Hart, Shaffner & Marx, the well-known Chicago clothing manufacturers, won a large building which is protected by an automobile sprinkling system of a very modern and reliable type. The sprinkling system extends throughout the building. Pressure in the pipes is maintained by a 2,000 gallon compression surge tank, which is normally half full of air at 150 lbs. pressure and acts as a cushion for the system. Water is kept in the surge tank under a pressure of not less than 140 lbs. by a motor operated pump, shown in the accompanying illustration. The pump’s capacity is 1,000 gallons per minute at 150 lbs. per square inch pressure in excess of the supply pressure in the city main which is about 25 lbs. The motor starts the pump automatically when the pressure drops to 140 Ihs. The air cushion tends to compensate for light leakage, so that practically constant pressure is maintained; frequent starting of the motor to replace small losses is therefore avoided. Under present conditions the outfit operates once in about every ten days and runs but a few seconds until full pressure is restored in the tank. The entire installation is provided with telegraphic indicators. One shows the exact height of the water below the cut-in pressure of the pump; another level in the air cushion tank; another whether the pressure on any part of the system drops tells whether the voltage is cut off from the control panel outside or at the switchboard. All main valves are provided with alarms which sound when the valves are closed. The pump is of the horizontal three-stage pattern, built by the Jeanesville Iron Works Company. Besides keeping up the pressure in the surge tank, the pump feeds a standpipe service, so that hose connections may be made at several points on each floor in case of fire. A gravity roof tank, of 40,000 gallons capacity is used as an auxiliary to the pump in feeding the sprinklers should anything happen to the motor, pump or control. This roof tank, however, is not connected to the standpipe system. The latter has to rely on regular steam fire engines in case of failure of the electric pump. The pump is so constructed that it is impossible to overload the motor in case of excessive water flow such as would he occasioned by the bursting of one or more hose lines. The pump casting is spit horizontally and the suction and discharge connections are both in the lower half; thus the upper half may be removed for inspection and repair without disturbing the main Connections, in addition to the two main hearings o fthe pump a marine type thrust bearing is provided at the end of the shaft for the purpose of taking up the end thrust. This bearing is supplied with forced lubrication by means of a scoop shaped oil thrower. The thrust bearing is also water jacketed, the water being taken from a connection made to the third stage of the pump, and its flow automatically regulated. The illustration also shows the hose connections provided on the discharge pipe for use in case of fire in the basement. The motor is built in acBoard of Fire Underwriters, which specify the following: The motor must be entirely enclosed and provided with a ventilating blower on the end of the shaft. The air intake must lead to an adjoining room so as to insure cool air being furnished to the motor. It must also be water proof. The air outlet pipe must be turned down so as to prevent falling water from entering the motor casing. The motor frame must be water proof up to its center line. All covers provided with rubber gaskets to keep out falling or other accidental flow of water in the engine room. The leads must be brought out above the center line so that they will not be damaged by water until it gets up to the shaft. With continuous operation at full load the rise of temperature in the motor must not exceed 40 degrees. The motor is of Westinghouse make, direct current. 150 h. p., 1,400 R.M.P. volt, and designed especially for service of this kind. The control which was furnished by the Cutler Hammer Company, is automatic, although it is arranged for hand operation in case of emergency. The installation described reduced the insurance premium on the building approximately onehalf.

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