Water
Lifting
There
are several devices for lifting water from low level water reservoirs,
such as wells, lakes and rivers. Following water lifts are in use in
India.
- Those worked by
human power viz., (a) swinging basket and (b) picotah.
- Those worked by
bullock power viz., (a) iron or leather mhote (b) Persian wheel (rahat)
- Those worked by
engine or electric power viz., (a) oil engines and pumps and (b)
electric motors and pumps of various horsepower.
Appliances
Worked By Human Power
This
water lift usually consists of fibre basket or metal can with a capacity
of two to three gallons. It is used to lift and throw water into the field
channel 60 to 90 cm., above the water level in the reservoir. It can lift
800 gallons (3,640 litres) of water per hour to a height of 45 to 60 cm.
This
water lift is worked on the principle of levers. It is very economical and
efficient in lifting water from shallow wells to a height of 3.5 to 4.5m.
The lift consists of a strong log laid across a fulcrum, a basket attached
to the long arm by means of a bamboo or a rope and a heavy weight. It
requires to men, when the bucket is full one gently releases the rope and
the bucket comes up as the stone goes down. The bucket is emptied into the
field channel and again lowered into the well.
Appliances
Worked By Bullock Power
The
mhote bucket is made of either metal or leather and holds about 40 to 50
gallons of water. At the bottom of the bucket there is leather spout,
which is operated by a separate rope attached to the yoke of the bullocks.
A second and stronger rope is fastened to the top of the bucket and runs
over pulley to the bullock yoke. When the bullocks run down the inclined
plane, both the ropes are pulled. The one attached to the mhote filled
with water lifts the mhote and the other tied to the spout keeps its mouth
upwards and prevents spilling any water. When the mhote reaches the top
the spout opens and water runs into a trough and then into the field
channel. The bullocks then back up to lower the mhote in the well and the
operation is repeated.
It
consists of one long iron axle about 4.5m., long with one large gear wheel
at one end and one small gear wheel at the other end. The iron axle is
laid on the ground such that the large gear wheel can rotate freely into
the well. The length of the chain is such that one or two lower most
buckets dip into the water in the well and get filled up. The gear at the
other end of the axle meshes with another gear which is fastened to a
shaft that extends at right angles and upward about 90 cm. A pole is
fastened at right angles to this upright shaft and is pulled by bullocks
walking in a circular motion. As the bullocks pull the pole around, the
gear wheel turns and that in turn moves the chain with buckets full of
water on upward journey.. This is used for lifting water from a well up to
a depth of about 6 to 9 m., and can deliver about 2,500 gallons (11, 375
litres) of water per hour.
Appliances
Worked By Engines and Electricity
Horizontal
and turbine pumps worked with petrol, diesel or electric motors, are the
most popular water lifting devices of today. They are of various
capacities, up to 2,00,000 1/hr or more. A large area can be commanded
with pumps having such capacities
Oil
engines and pumps
Oil
engines used for pumping water are commonly from 5 to 10 horsepower with
pumps 5 to 10 cm., in size. These have to be fitted within 22 feet (6.6m.)
of the water level and hence in deep wells have to be installed inside the
well on a platform. The water once sucked in by the pump can be delivered
to any height one likes. Oil engines are easy to manage and if properly
maintained and looked after will serve for at least 10 to 15 years.
- Electric
motors with pumps
Because
of their economy and very little maintenance and care, electric motors are
rapidly replacing oil engines in villages where electricity is available.
It is advisable to consult agricultural extension officer regarding the
horsepower of oil engine, to purchase of right kind of motor with pump
etc. |