Module 10: Water Pumping Equipment Flashcards
mechanical device used for transferring water from one place to another
water pump
the usual source of water of a pump
- lower elevation than the point of delivery
- wells, rivers, lakes, reservoirs, and canals
they are essential for good health and sustained agri prod
water pump
technical terms in pumping
volume of water pumped per unit of time
discharge
technical terms in pumping
form of the energy content of the liquid per unit weight of the liquid
head
basic principles in pumping water
- atmospheric pressure
- specific gravity
- centrifugal force
2 pump classification
- positive displacement pump
- variable displacement pump
pump classification
discharges the same volume of water regardless of the head against which they operate
positive displacement pump
pump classification
inverse relationship between discharge
rate and pressure head
P = Q up x D down
variable displacement pump
type of positive displacement pump
having to-and-from motion
reciprocating pump
basic parts of a recipro pump
- piston or plunger
- cylinder
- inlet or admission valve
- outlet or discharge valve
2 types of recipro pump
- lift pump
- force pump
2 types of recipro pump
single-acting pump na may open cylinder, piston with built-in bucker valve.
nili-lift water to flow out from a spout
lift pump
2 types of recipro pump
forces the water above atmospheric pressure as distinguished from the lift pump
may single or double acting pump
force pump
major parts of a variable displacement pump
- impeller
- shaft
- casing
part of a varia disp pump
converts mech energy into fluid energy by the forcig the liquid to move into rotary motion
impeller
part of a varia disp pump
it is a wheel or disc mounted on a shaft and meron blades and curved vanes
impeller
part of a varia disp pump
transmits power from a prime mover to the impeller
shaft
part of a varia disp pump
intro the liquid into the impeller, collects the liquid leaving the impeller and guides it away under an increased pressure
casing
types of variable displacement pumps according to hydraulic configurations represented by the arrangement of the impeller and the casing
- propeller (axial flow) pump
- mixed flow pump
- centrifugal (radial) pump
types of variable displacement pumps according to hydraulic configurations represented by the arrangement of the impeller and the casing
used for low pressure/head and high discharge
drainage pumping
transfer of water from canals
propeller (axial flow) pump
types of variable displacement pumps according to hydraulic configurations represented by the arrangement of the impeller and the casing
combines features of centrifugal and axial flow pumps in which head is developed partly by the centri force and partly by the lift of the vanes
mixed flow pump
types of variable displacement pumps according to hydraulic configurations represented by the arrangement of the impeller and the casing
most used for domestic and irrigation purposes
centrifugal (radial flow) pump
types of centri pump according to energy conversion
- volute type (spiral) **reduces velocity
- diffuser (may diffuser vanes) **small openings
types of centri pump according to energy conversionr of stages
- single stage (single impeller)
- multi-stage (2 or more impellers in one shaft and casing)
types of centri pump according to type of impeller
- open impeller **small solids
- semi-open/semi-enclosed impeller **w/ suspended sediments
- enclosed impeller **for clear water
types of centri pump according to type of suction inlet
- single suction **suction cavity on one side only
- double suction **both sides meron
types of centri pump according to axis of shaft rotation
- horizontal
- vertical
SHAFT HA
types of centri pump according to method of drive
- direct connected **directly to driver
- close-coupled **single unit (shaft + bearings and driver)
- belt driven **may pulley head
a criterion that is well accepted in computing the pump capacity is to base it on the ??
highest daily water requirement of the crop
according to the National Irrigation Admin. (NIA),, the water req for rice prod is ___mm/day
10 mm/ day
this provides an economical installation when an adequate and reliable source of electric power is available at reasonable cost
electric motors
_______ should be used when the source
of electric power is not reliable or too
costly
engine
this is the discharge rate of a well per foot drawdown
specific yield of well, SY
a low horsepower driven axial flow pump with a capacity of up to 3000 liters per minute.
IRRI axial flow pump
ideal for small-farm irrigation where engine-driven pumps are generally too expensive
IRRI “tapat-tapak” pump
formula for total drawdown
discharge rate (gpm) / specific yield (gpm/ft drawdown)
formula for horsepower needed to drive the pump
hp sub pm = Q x H all over 3960 x Eff sub s
