2. Sprayers and Dusters
Are used for application of
• Herbicide to remove weeds
• Fungicide to minimize fungal diseases
• Insecticide to control insect / pests
• Micronutrients on the plants
3. Sprayer
• Is a machine used to apply fluids in the form of
droplets
Functions:
• Break the liquid into fine droplets
• Distribute the chemical uniformly on the plant
surface
• Regulate the amount of fluid to avoid excessive
application
4. Sprayer's classification
Based on power source, sprayers may be classified as:
(i) Hand operated machines - suitable for small holdings. They are
operate pressure ranging from 1 to 7 kg/cm².
(ii) Power operated machines - suitable for treating a large area. They
are operated pressure ranging from 20 to 55 kg/cm².
(iii) Air planes-suitable for large scale work.
• Based on pray volume, sprayers may be classified as:
• High volume spray (more than 400 litres spray/ha)
• Low volume spray (5 to 400 litres, per hectare)
• Ultra low volume (ULV) spray (less than 5 litres spray/ha).
5. Types of sprayers
• Manually Operated
– Hand Sprayer
– Foot Sprayer
– Rocker Sprayer
– Knapsack Sprayer
– Hand Compression Sprayer
– Bucket Pump Sprayer
• Power Sprayer
6. Hand Sprayer
• Consists of small
container for solution,
plunger pump and nozzle
• Provided with single
action or continuous
action air compression
pump
• Commonly used in
household works and
kitchen garden
7. Knapsack Sprayer
• Consists of a 9-22 liters capacity tank made of brass, galvanized
iron and high density polythene
• The tank is carried at the back
• Adjustable shoulder straps are provided for proper holding
• Has a airtight chamber
• Hand lever is provided for pumping
• A few stroke of pump build up enough pressure in the air
chamber
8. Components of Knapsack Sprayer
• Tank to hold chemical
• Hand pump to create pressure
• Filtration system behind the nozzle tip to
reduce blockages
• Control Valve to control pressure and turn of
the sprayer
• Nozzle tip to control application rate an
produce the correct size droplets
9.
10. Foot Sprayer
• Consists of a container, pump, spray
lance or boom with nozzles, control
valves, suction and delivery hoses,
strainer and handle with foot paddle
• Pump consists of two part:
– Pump barrel
– Pressure chamber
• Commonly used in orchards,
gardens, tea and coffee states and
rubber plantation
11. Power Sprayer
Types
• Knapsack Power Sprayer
• Trailer Power Sprayer
• Tractor Mounted Power Sprayer
• Drone Sprayer (Air Spraying)
12. Care and maintenance of sprayer
(i) All washers and pickings should be soaked in oil or water
before use.
(ii) The ends of the nozzle should be unscrewed and cleaned
before starting the work.
(iii) When spraying is over, the sprayer should be operated for
some time with clean water to remove sediments from the
pressure vessel and the discharge tube.
(iv) for off season storage, the sprayer should properly be kept
in a cool and dry place
13. Dusters
• Are used to apply the chemicals in dry power
form.
• Consists of:
– Hopper
– Agitator
– Feed control
– Fan or Blower
– Delivery Nozzle
14. Types of Dusters
• Plunger Type Hand Duster
• Rotary Duster
• Power Duster
15. Plunger Type Hand Duster
• This machine consists of a chamber for the
dust, outlet, a cylinder with piston, piston rod
and handle.
• By moving the piston back and forth in the
cylinder, dust is forced through the outlet.
• This type of duster is suitable for dusting a
small area.
16. Rotary Type Hand Duster
• This type of duster) is provided with an enclosed fan
geared to a hand crank and a hopper holding the dust.
• It is equipped with an agitator to stir the dust and a
regulator to control the discharge opening.
• The right hand is used for cranking and the left hand to
guide the discharge tube.
• It consists of a hopper, a fan, gear box, handle, delivery
hose and a deflector plate.
• When the handle is rotated, the fan rotates at high
speed and draws air from outside
• These dusters can hold about 3.6 to 4.5 kg of dust and
are large enough to treat 0.4 to 0.6 hectare of land.
17. Power Operated Duster
• The power duster of small capacity is generally mounted
on the back of the operator.
• It consists of cylindrical container, blower, high speed
engine and discharge hose pipe.
• The cylindrical container is provided with two
compartments, one for gasoline, and the other for the
powder to be dusted.
18. Care and Maintenance of Dusters
a. Duster should be thoroughly cleaned before and after use with a
suitable brush.
b. The hopper should be filled with dust about half of its capacity.
c. The lid of the hopper should be closed during the operation.
d. In rotary dusters, the handle should be cranked at 30 to 35 rpm for
efficient performance.
e. Before and after use of the duster, the dust from the fan box,
suction pipe and hopper should be thoroughly blown out.
f. Pieces of paper, gunny bag and other foreign materials should be
prevented from getting into the hopper.
g. For motorize knapsack dusters, proper lubrication should be
maintained.
h. For off season storage, the duster should properly be kept in a cool
and dry place.
