Horizontal split case pumps
The casing in which the shaft and impeller rotates is split in the middle and can be separated thus exposing the shaft bearings and impeller. There are two types horizontal mounted and vertical
Major parts of a centrifugal pump
Water enters the pump through the eye of the impeller
Single stage pump
A pump with one single impeller. Most horizontal split case pumps are
Multistage pump
Multiple impellers . Have the ability to deliver high pressures and are commonly use for standpipe water supply in high-rise buildings
Stevenor pressure rating for pumps
There are no standard pressure rating however no fire pump is permitted to have a pressure rating less than 40 psi
Packing glands
Designed to prevent excessive water leakage around the shaft
Vertically mounted split case pumps
Is the same as a standard horizontal split shift pump and has the identical applications. The impellers rotate on a shift within the pump casing the water his discharge in a direction perpendicular to the shaft . Originally designed for Wells Have more th
Vertical pump.
Pump drivers
Are the engines or motors use to turn the pump
Pump power
Are required to run under all load conditions which include pumping at churns and pumping at 150 psi of rated capacity
Churn.
Churn or shut off when it is running but all discharges are closed
Electric motors
Not originally designed for this purpose , must meet national electrical manufacturers association
Vertical shaft pumps electric motors
Must have anti-reverse ratchet that prevents the motor from turning red birds. The motor must also be equipped with a thrust bearing to carry the weight of the pump plus withstand the thrust of the water
Advantages and disadvantage is of electric motors
Relatively small amount of maintenance required. Proper lubrication of the motor bearing in accordance with manufacturing instructions is all that is required. Disadvantage of electric motor involves reliability. Storm fires are other accident involving p
Diesel engine drivers
In common reliable method. Although it is usually more expensive than gasoline or about your drivers. Diesel drivers may be a better choice because it does not rely on external power
Engine power
All her required to have a governor if the governor fails to limit pump speed this device will shut down the engine to a speed approximate 20% above the rated engine speed
Gear drives
Horizontal split case pump there is usually no gear between the engine and the pump. The vertical shaft pump is driven by a diesel Hunjan through them right angle gear drive with universal joints. The gear drive must also be equipped with the anti-ratchet
Engine requirements
Two means of recharging the batteries must be provided. One means of recharging is to use the generator or alternator that comes with the engine the other is to use about automatic charger that takes power from an alternating current source . Must be capa
Pump room temperatures
Fire pump room should be maintain a temperature of 70�
Controllers for electric motor driven pump
Circuit breaker
Should allow at least 115% of the rated full load current without tripping
Isolation switch
Located between the power supply and circuit breaker.
Pilot lamp
Should be visible without getting inside the controller it's purpose is to indicate when the power is available to the pump controller panel
Emergency start lever with latch
This switch can be latched in the operating position for continuous for nonautomatic operation, independent of timer for automatic start mechanisms
Running. Period timer
Is used to shut off the motor after being started. The running period Timer should be set for at least 10 minutes
Pressure switch
Is set to close the circuit and turn on the fire pump if the water pressure of the system drops below the switch setting. Most are Mercury switch type
Jockey pump
Is used to maintain the systems pressure to prevent falls pump starts
Diesel engine controllers
Are not interchangeable with controllers for electric motors
Fire pump pipe and fittings
Os&y Val must be located in the suction line for control of water supply. Butterfly valves are not permitted due to turbulence
Eccentric reducer
Reduces or illuminate the possibility of your pockets
Relief valves
Should be located between the pump and discharge check valve. Should be set to open a little above the normal discharge pressure when the pump is operating at churn
Circulation relief valve
Not present pump electrical Trippin pumps hey smaller valve will be president it is designed to open and provide enough water flow in and out of the pump to prevent the pump from overheating when it is operating at churn against a close system
Horizontal split case fire pump
Vertical shaft pump
Modern times must meet the three standard points
A maximum of 140% of rated pressure and flow of zero GPM, a minimum of 100% a rigid pressure and 100% of rated flow, a minimum of 65% a rated pressure at 150% of flow rate