Difference between revisions of "Pumps"
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All about pumps. Please contribute & help complete the article. | All about pumps. Please contribute & help complete the article. | ||
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==Flow & Head== | ==Flow & Head== |
Revision as of 20:40, 29 June 2007
All about pumps. Please contribute & help complete the article.
(See discussion on this article in the uk.d-i-y newsgroup)
Flow & Head
Real world flow rate is normally far below the manufacturers claimed flow rate. Flow claims are normally based on there being no pipe connected to the pump outlet. In the real world:
- The pump operates against a column of water (or head) which provides back pressure
- Pipes have resistance to water flow
A better idea of real life flow can be gained by plotting head versus flow rate on x,y axes, and drawing a straight line from max flow to max head. This enables flow rates to be read off for any given head. This does not take piping resistance into account, which will lower flow rates further
More Head Please
Plumbing 2 pumps in series gives a total head of the 2 pumps added together.
Pump Power
Pump Materials
- Brass: used for potable water
- Plastics: some are approved for potable water
Connections
Pump Types
Central Heating circulator
- Very quiet operation
- Long service life
- Speed adjustable.
- too fast can cause pumping over & noise
- too slow can cause boiler kettling
- Standardised pipe fittings.
Shower
- Boost shower pressure and thus flow
- Boosts bills too.
Sump pump
- For draining cellars prone to flooding.
- USually automatically operated by a water sensor
Drill Pump
- Small minimal cost pump for occasional clear-up use
Foul Water Pump
- Able to handle debris in the water