| T/F Positive displacement pumps operate on the principle that liquid is displaced by
mechanically varying the chambers within the pump body? | True |
| T/F Positive displacement pumps need to be primed before use | false
(They do not need to be primed before use) |
| T/F Liquid is drawn into the pump body because the chamber's volume is changing | True |
| T/F PD pumps are fitted with a relief device to allow for liquid to return to the suction side | True |
| T/F The flow rate and volume for these pumps is usually quite high | False
(Low) |
| T/F The reciprocating pump is the simplest version of a PD pump there is | True |
| T/F reciprocating pumps can be both single and double acting | True |
| In electrically driven reciprocating pumps the handle is replaced by a crankshaft that is attached to the spindle. | False
(reciprocating pump has a connecting rod, not a spindle) |
| T/F As the mechanical shaft rotates it converts rotary motion to
reciprocating motion and actuates the piston within the reciprocating pump | True |
| T/F Reciprocating pumps are found in high pressure fuel systems | True |
| T/F Reciprocating pumps are found in bilge systems | true |
| T/F Reciprocating pumps are found in pressurized HVAC systems | False
(they are found in high pressure fuel systems and bilge systems) |
| Rotary motion pumps use rotary motion to vary the volume of the chamber within the pump body | True |
| There are three kinds of rotary pump | False
(Gear Pumps, Screw Pumps, Vane
Pumps, and Progressive Cavity Pumps) |
| A screw pump is an example of a rotary motion pump | true |
| a rotating vane pump is an example of a rotary motion pump | true |
| gear pumps come in three types: internal gear pumps, external gear pumps, and diternal gear pumps | False
(diternal does not exist) |
| an external gear pump contains two gears, one with internally cut teeth and the other with externally cut teeth | Fasle
(This is the description of an internal gear pump) |
| external gear pumps contain two gears with externally cut teeth that mesh together while rotating. | True
(as the teeth disengage with one another the space formed between the teeth and casing increases volume.) |
| a small amount of liquid leaking back to the inlet port is called spill | False
(term: Slip) |
| both gears in an external gear pump are usually driven by an electric motor or related machinery | False
(Usually one gear is driven and the second gear is rotated
by this driver) |
| external gear pumps cannot handle any particulate in the liquid it is pumping, or else the pump fails | False
(external gear pumps can handle small particulate but this increases the wear between moving and non moving parts) |
| an internal gear pump contains two gears; a small driver gear powered by a motor or related machinery and a larger rotor gear powered by the driver gear. | False
(the large gear is the driver gear and the small gear is the rotor gear) |
| internal gear pumps can be found as lift pumps in fuel oil supply systems | True |
| Vane pumps are not positive displacement pumps | False
(they are) |
| rotary vane pumps have a central rotor that is fitted
with vanes and turns inside an eccentric casing | True |
| the vanes in a rotary vane pump are constructed out of low friction materials such as PVC or ABS plastics | False
(they are made primarily out of carbon or steel) |
| rotary vane pumps are used in hydraulic systems | true |
| a rubber impeller is another form of rotary vane pump | true |
| The progressive cavity pump has a helical screw rotor fabricated from chromed carbon steel that turns inside a flexible rubber casing called the stator. | True |
| The stator is encased in a metal casing for strength | True |
| as the rotor turns inside the progressive cavity pump, a cavity is formed at the suction end and traps the fluid | True |
| progressive cavity pumps can operate at high speeds | False
(low speeds) |
| progressive cavity pumps are used mainly for pumping bilges waste or on sewage systems | True |
| The progressive cavity pump is incapable of processing large amounts of particulate suspended in the transported medium | False
(is capable of handling fluids containing large amounts
of suspended solids.) |
| The rate of flow in a swash plate pump will be infinite in both directions | True |
| positive displacement pumps are self priming | True |
| positive displacement pumps require a separate suction priming system | False
(They do not require one, although one may be fitted) |
| making a reciprocating pump double valved will increase the efficiency of the pump | False
(term: double acting) |
| in an internal gear pump the inlet is sealed to the outlet by a crescent shaped insert | true |
| spring activated suction and discharge valves must be fitted to a reciprocating pump | true |
| the vanes in a vane pump are held against the casing by centrifugal springs | false
(integral slots hold the vanes against the casing) |
| what type of pump is normally used for engine lubrication? | Rotary screw |
| progressive cavity pumps are utilized in systems where high turbulence is not an issue | false
(these pumps are used in low turbulence systems) |
| flow rate in a positive displacement pump is usually quite low | true |
| the meshing together of the teeth in a gear pump creates pressure | true |
| rotary screw pumps can have multiple driven screws | False
(one driven screw) |
| axial piston pumps have pistons attached to a swash plate | true |
| positive displacement pumps move fluid by centrifugal force | False
(by mechanically varying the volume of a cavity) |
| radial piston pumps produce low pressure | false
(high pressure) |
| positive displacement pumps come in two main categories: rotary and reciprocating | True |
| Rotary vane pumps are positive displacement pumps that have a central rotor that is fitted
with vanes and turns inside an eccentric casing | true |
| rotary vane pumps are used primarily in fuel systems | false
(they are used in hydraulic systems) |
| progressive cavity pumps can operate at high speeds | False
(they operate at low speeds) |
| the driveshaft on a progressive cavity pump will be fitted to a reduction gearbox | True |
| reduction cavity pumps are used mostly in bilge or sewage systems where suspended solids are expected | True |
| the helical screw in a progressive cavity pump is constructed from chromed carbon steel that turns inside a flexable rubber casing called the stator. | true |
| screw pumps are used primarily in lube oil pumps | true |
| axial piston pumps have an even number of pistons more often than an odd number | false
(more often having an odd number of pistons) |
| the housing of a axial piston pump is also known as a cylinder block, rotor, or barrel | True |
| a bent axis pump is most commonly used in hydraulic circuits | true |
| a 'valve plate pump' and a 'swash plate pump' are the same | True |
| check ball pump is also known as a wobble bottom pump | False
(term: wobble plate) |
