Lifting From Open Water

Question 1

List examples of open water supplies

Answer 1

Rivers 
Canals
Lakes
Docks
Swimming pools
Wells

Question 2

Define the principle of lifting from open water

Answer 2

Atmospheric pressure exerts a downward force of 1 bar on every part of earths surface. So when a vacuum is made in a, water would be pushed by atmospheric pressure up the tube

Question 3

What is the practical lift of water achieved?

Answer 3

8m

Question 4

The practical lift is 8m and not 10m due to what factors?

Answer 4

‘OFPITA’

Overcoming inertia 
Frictional loss
Pump entry loss
Imperfect vacuum 
Temperature
Atmospheric pressure

Question 5

What is the term priming defined as?

Answer 5

A device which can pump air

Question 6

What is the equipment used when lifting from open water?

Answer 6

Hard suction hose
Suction strainers
Strainer basket 
Suction wrenches
140-100mm adaptor
Short line
Salvage sheet

Question 7

What are the safety and practical considerations?

Answer 7

Personal floatation device

Make sure the appliance is on steady ground

At night set up a lighting to make the area around the pump safer and easier for pump operating, especially when using the LPP

Aware of water borne diseases

Question 8

A minus reading on the compound gauge can be interpreted as what?

Answer 8

A lift of a metre

E.g. -0.3 = 3m

Question 9

What is the lift measured from?

Answer 9

The eye of the impeller to the surface of the water

Question 10

Reasons for an increase in the vacuum reading on the compound gauge?

Answer 10

Level of supply dropped

Suction strainer blocked

Branches opened

Burst delivery hose

Question 11

Reasons for a decrease in the vacuum reading on the compound gauge?

Answer 11

Level of supply raised

Branches shut down

Slight air leak on suction side of pump