Duster is a machine to apply chemical in dust form. Dusters make use of air streams to carry pesticides in finely divided dry form on the plants.
A duster essentially consists of:
1. Hopper
2. Agitator
3. Feed control
4. Fan or blower and
5. Delivery nozzle.
Types of Duster:
There are several types of dusters in the common use, such as:
1. Plunger Type
2. Knapsack Type
3. Rotary Type
4. Power Operated Duster
1. Plunger Type Duster:
It is a simple duster with a small piston. The piston drives a current of air over the dust in the hopper. The dust is carried away through a delivery spout. Small hand pump dusters of this type are available and are suitable only where the area to be dusted is small like vegetable or flower garden.
2. Knapsack Type Duster:
It is a duster with the powder container on the back of the operator. Knapsack dusters have a hopper through which a current of air is blown to pick up the dust. The air current is produced by lever operated leather bellows. Shoulder straps or carrying straps are generally provided in such dusters and they can be easily carried in the fields. These dusters are suited for small areas only.
3. Rotary Duster:
It is a duster with a hand operated rotor in front of the operator. For spraying tall crops, more force of delivery is required, hence rotary dusters are preferred. Dust is fed from a hopper into a current of air produced by a rotary fan and is blown out through a delivery pipe.
Most of the models have stirring device, actuated by the fan crank to ensure a steady flow of dust. The rate of delivery can be regulated by a valve below the hopper. The delivery force is controlled by controlling the speed of the fan.
4. Power Operated Duster:
Power operated duster mainly consists of a power driven fan, a hopper and a delivery spout. The fan creates strong air flow which causes the dust to blow off from the hopper to a considerable distance either vertically or horizontally. The direction of the dust is regulated by a movable delivery spout suitably fitted with the unit. These types of dusters are used for large areas.
Care and Maintenance of Dusters:
1. Duster should be thoroughly cleaned before and after use with a suitable brush.
2. The hopper should be filled with dust about half of its capacity.
3. The lid of the hopper should be closed during the operation.
4. In rotary dusters, the handle should be cranked at 30 to 35 revolutions per minute for efficient performance.
5. Before storing the duster after use, the dust from the fan box, suction pipe and hopper should be thoroughly blown out and the agitation shaft should be profusely oiled while cranking.
6. Pieces of paper, sacking and other foreign materials should be prevented from getting into the hopper.
7. The agitator parts and dust feed should be occasionally checked for blockage by foreign matters.
Essential spare parts to be kept in stock:
1. Agitator
2. Feed control lever
3. Feeding brush
4. Shaft for crank
5. Crank handle
6. Hose couplings and clips
7. Breast plate
8. Nozzle
9. Nuts and screws.
General precautions for the safe use of insecticides:
1. The name on the container should be read carefully and manufacturer’s instruction should be followed.
2. The pesticides should be kept always in container with proper name.
3. The pesticides should be stored in a safe and locked place so that children may not touch them.
4. The pesticides should never be placed near food stuff or medicines.
5. Empty containers of dangerous pesticides should not be used for any alternative purpose.
6. Necessary protective clothing should be used while handling pesticides. The pesticide bags should not be torn but it should be cut with a knife.
Seed Dresser:
It is a machine to apply coating of protective chemicals to seeds.
Fumigator:
It is a machine to generate and distribute gases or smoke.
Flame Gun:
It is an apparatus to kill weeds by a flame.
Power Sprayer Cum Duster:
It is a power operated sprayer which can be converted as duster when desired.