07 Types of Pumps Flashcards
Amount of water discharged from a piston pump is determined by:
- The size of the piston
- The length of the stroke
- Number of strokes per minute
- Number of pistons
Piston Pumps are still used today for:
high pressure applications like brush and windland firefighting.
Efficiency factors of centrifugal pumps:
- Pressure
- Speed
- Quantity
The pump will run dry if:
- it does not have enough intake water
- too high a lift
- operator tries to pump more water than what is available.
Parts of the centrifugal pump
- Eye of the impeller
- Impeller, between two shrouds (discs)
- Shrouds form void space that holds water
- Vanes (between shrouds)
- Volute (edge of impeller)
The efficiency of a double-suction eye is most apparent when drafting and at higher altitudes. At high elevations a double eye can be upward of 50% more efficient.
_________ is what gives water the velocity it needs to build pressure.
Vanes
_________ is where the water is given its direction toward the discharge valves.
Volute
Transfer Valve
transfers water from one impeller to the other OR to both at the same time
Three positions from which the pump operates
- From the front of the crankshaft
- From the drive shaft
- From a power takeoff
Advantages of Crankshaft
- Simple to operate, simple controls, easy to engage
- Operations are in front of the truck
- Independent of the drive shaft - pump and roll
Disadvantages of Crankshaft
- Pump sits out in the open / can freeze
- Size of pump is limited to space
- While moving, pump discharge is dependent on engine speed
- Clutch can slip due to movement of rig
Midship mounted pump is most common. Pump transmission is placed between the engine and the rear wheels.
Advantages of Midship-Mounted
- Full power of engine is available for pumping
- Larger pump sizes
Disadvantages of Midship-Mounted
- Power is directed either to the wheels or the pump
- More mechanical parts are needed
- A manual override is needed for an electrical shift operation
