When spraying with a hand-carried sprayer, you should first raise the rocker several times to make the air pressure in the air chamber reach the working pressure, and then turn on the switch to spray while walking. If you feel heavy when you press the joystick, you should not use excessive force to prevent the air chamber from exploding. For old-fashioned sprayers, generally use 2~3 steps to move the rocker up and down once, and move the rocker 18~25 times per minute. During operation, when the liquid medicine in the air chamber exceeds the safe water level, the pump should be stopped immediately to avoid explosion of the air chamber.
When using a compressed sprayer, the dosing liquid should not exceed the specified water level to ensure that there is enough space to store compressed air to make the spray pressure stable and uniform. Compression sprayers without safety valves must be pumped according to the number of pumps specified in the product manual. It is forbidden to extend the lever to pump and two people to pump together to avoid overpressure explosion of the liquid medicine barrel. During the use of the compressed sprayer, the pressure in the medicine tank will continue to drop. When the spray nozzle atomization quality decreases, the spraying should be suspended, and the air pressure should be recharged to ensure good atomization quality.
The manual sprayer should be used for constant spray, and it can be used for drift spray or targeted spray for low volume spray. Different spray methods should be selected for different crops, different diseases, pests, and pesticides.
1. When spraying herbicides with manual sprayers, firstly, the herbicides should be deposited and distributed uniformly in the field to avoid the herbicide damage caused by excessively large doses of local plots; secondly, there should be less fine droplets that are easy to drift and avoid fog drops Drifting causes phytotoxicity of neighboring sensitive crops. Therefore, fan-shaped spray nozzles should be used for herbicide spraying. When spraying, the height of the nozzles from the ground should be kept consistent, and the walking route should be kept consistent; when conditions permit, small spray rods with double nozzles, three nozzles or four nozzles can be installed.
If the sprayer is equipped with a hollow cone spray nozzle, in order to spray the herbicide evenly on the surface, the operator needs to swing the spray rod while walking to make the nozzle swing in a "Z" shape to prevent uneven distribution of the deposit. In order to reduce leakage and ensure that the coefficient of variation of chemical deposition distribution is not greater than 15%, it is required that the amount of chemical liquid applied should not be less than 40 liters per mu.
2. When using a hand sprayer to prevent and control crop diseases and insect pests, it is best to use a small spray film, and do not use nails to artificially blow up the spray head. This is because the pesticide droplets produced by the small spray nozzle are fine, which has a good effect on pest control.
3. When using a hand sprayer to spray contact insecticides to prevent and control pests (such as cotton seedling aphid) that inhabit the back of crop leaves, the nozzle should be upward and the leaf back directional spray method should be used.
4. Use a manual sprayer to spray protective fungicides. The spray should be applied before the plants are not infected by pathogenic bacteria or at the initial stage of infection. The fog droplets are required to be deposited and distributed evenly on the plant target and have a certain fog drop coverage density.
5. When using a manual sprayer to spray herbicides between rows, be sure to configure a nozzle protective cover to work on the target to prevent droplets from drifting and causing damage to neighboring crops; when spraying, the height of the nozzles should be consistent, and the agent should be evenly distributed and not respray And leaking spray.
6. When several manual sprayers are spraying at the same time, they should use a trapezoid to advance, and the person on the leeward side should spray first to prevent the body from contacting the liquid.