Abstract:
Groundnut threshing is a fundamental process in post-harvest management. The threshing process is
done using manpower and machinery. The majority of groundnut growers separate the groundnuts by
their hands. But the manual threshing process is inefficient and it is a very time-consuming process.
At present, imported threshing machines with various capacities are used by Sri Lankan farmers for
threshing the groundnut of Sri Lankan varieties with the limitations of those imported machines. The
main reason is for the low productivity of imported threshing machines is that the machines are
designed based on the specifications of the groundnut types available in those countries. The
objectives of this project are (i) to design and develop a machine for threshing the groundnut pods
from the groundnut bushes after harvesting and (ii) to develop a low-cost and efficient groundnut
threshing machine for local varieties. Several field visits were made to find short coming of the
available machines. Based on the field visit information, a three-dimensional design of the threshing
machine was designed to avoid those short comings. The designed threshing machine is powered
mechanically and size of the machine is smaller (L=1750mm) than the others. New improvements in
the current design are being made by analyzing farmer’s data and their ideas. In this process, two to
three days after the groundnut harvesting, the bushes are threshing, which reduces the force required
to separate the pods from the bushes that should be minimized damage to the pods internally and
externally. This developed threshing machine can adjust the scale of air blower input area, that air
input requirement scale depending on the type of groundnut. The main difference between groundnut
varieties is the mass of pods. This threshing machine gives positive feedback to groundnut farmers to
grow several types of groundnut in large quantities and contributes to the growth of the local
economy.
Keywords: Groundnut threshing machine; Field efficiency; Groundnut varieties
