Below are a couple of options that have been used for boom sprayer setup for 2WT. These may not be the only options open, but may assist R. & D. workers in choice of the appropriate unit to fabricate.
There are several pump types which can be used;
First, one can use a diaphragm type as the pumping unit (picture on the right). It can be powered from the optional PTO outlet on the 2WT, an appropriate hydraulic pump connected to an suitable external shaft on the motor or transmission, or by fitting an extra Vee belt pulley to the 2WT motor.
Diaphragm pumps usually operate at 500-600 rpm which is ideal for some outlets.
A small gear pump, which also operates at 500-600 rpm, may be alternative.
Small centrifugal pumps are sometimes used. However they normally operate at 2000-3500 rpm, so need gearing up from some shafts, or a direct drive from the motor.
If no suitable outlet on the tractor is available, then a small 2-5HP petrol motor can be used as the motive power- either a 2 stroke or 4 stroke type. Some countries have small motor/pump combinations available in the market – usually of Chinese origin.
A small compact 12 volt diaphragm pump can also be used. However only 2WT’s fitted with an electric circuit and a battery are suitable. The other alternative is to incorporate a large on board 12 volt automotive battery, which must be recharged from the grid at regular intervals.
With all of these pump options a suitable pressure regulator must be incorporated into the plumbing circuit, to ensure a constant pressure at the spray nozzles, and also provide a proper bypass to allow for regular mixing of the spray liquid to avoid uneven concentration in the spray tank.
Article By: Jeff Esdaile