LPP & Open Water Pumping Flashcards
How many bar is atmospheric pressure?
1 bar.
How high is a theoretical water lift?
10 metres measured from the eye of the pump to the top of the water.
How high is a practical water lift?
8 metres measured from the eye of the pump to the top of the water.
What does CREST stand for?
Creating Flow
Resistance
Entry Loss
Strainer
Temperature
Explain Creating Flow from the CREST acronym?
Giving kinetic energy to the water as it changes from its static state to it’s moving state inside the suction hose
What does the compound gauge show?
Shows the inlet pressure of the pump.
When would the compound pressure show as positive?
When supplied from a hydrant
When would the compound pressure show as negative?
When lifting from an open water supply or overrunning the pressure supply.
What is the CREST acronym used for?
Factors to consider to overcome atmospheric pressure.
Explain Resistance from the CREST acronym?
Overcoming the frictional resistance in the suction hose and couplings
Explain Entry Loss from the CREST acronym?
Overcoming pressure loss due to turbulence and shock as the water enters the impeller
Explain Strainer from the CREST acronym?
Overcoming the pressure loss as the water is forced through the strainer and changes its direction of flow after entering.
Explain Temperature from the CREST acronym?
Overcoming any tendency for the water to vaporise as it nears the impeller.
What would a negative pressure reading of 0.1 bar indicate?
A lift from open water of approximately 1 metre.
What is the function of a primer?
To remove air from the pump and create a partial vacuum allowing atmospheric pressure to effectively force water up the hard suction pump.
When is a primer used?
Where there is a static water flow is lower than the pump
What could cause an increase in delivery pressure?
