Ministry of Agriculture,
Govt. of India
Northern Regional Farm &
Machinery Testing & Training Institute,
SUPER JET MULTICROP
Parts of thresher
When to threshing
Threshing is the process of collecting the
mature crop from the field.
Cutting: cutting the panicles and straw.
Hauling: moving the cut crop to the threshing
Threshing: separating the paddy grain from
the rest of the cut crop.
Cleaning: removing immature, unfilled and
Field drying: (optional) leaving the cut crop in
the field and exposing it to the sun for drying.
Stacking / Piling: (optional) temporarily storing
the harvested crop in stacks or piles.
1. Manual system
48 person/ days
Capacity: approximately 15
Threshing by impact
High shattering losses
Pre-drying might be
2. Pedal thresher
Wire loop threshing drum
Mainly combing the grains off the
straw, some threshing by impact
Maintains the straw
Needs winnowing after threshing
Wire loop threshing drum
3. Axial-flow thresher
Capacity: 0.3-3 tone/hour
Threshing through impact
Large range of sizes available
With or without cleaner
Truck mounted units
Can thresh wet crop
produced in 9 different countries
used by several 100,000’s of rice farmers across Asia
Axial flow principle
4. Super Jet Multicrop Thresher
There are three types of super jet multicrop thresher
1. Single Shaft thresher
2. Double Shaft thresher
3. Autofeeder thresher
Power efficiency is very more than conventional
Many crops like millet,wheat,castor,rice,corn,
soyabean can be threshed at better efficiency.
Cleaning process is done by combination of fan
and oscillating sieves.
Autofeeder for feeding the crops in cutterdrum.
1. Single shaft thresher
In this machine threshing rotor and
blowers are mounted on same shafts.
Required Input RPM to the threshing
shaft is given by belt and pulley drive
from the input power unit eg.
Tractor/motor or engine. . There are two
blowers mounted one is for suction and
throwing chopped waste and second is for
fine cleaning of the output grain. Body of
very heavy gauge welded steel plates with
the following features.
2. Double shaft thresher
To Remove seeds from the cobs by gentle
shelling action without damaging seeds. Empty
Cobs will be collected from the back side of the
thresher which comes out from the top of
reciprocating sieve chamber.
In this machine threshing rotor and blowers are
mounted on different shafts. Required Input
RPM to the threshing shaft is given by belt and
pulley drive from the input power unit eg.
Tractor/motor or engine. . There are two blowers
mounted one is for suction and throwing
chopped waste and second is for fine cleaning
of the output grain. Body of very heavy gauge
welded steel plates with the following features
3. sidedshaft thresher
Multi Crop Thresher also known as side shaft thresher
has threshing rotor and blower. This Machine is state of
the art design to handle different variery/size/shape of
grains and pulses. This machine can thresh almost all the
crops like castor, soyabean, maize, wheat, millet, cluster
bean, mustard, pegion pea, mung beans, peas, sunflower,
fenugreek, cumin seed, Isabgul(phylium), Rajgara,
coriander seed(dhaniya) etc…
In this machine threshing rotor and blowers are mounted
on different shafts. Required Input RPM to the threshing
shaft is given by belt and pulley drive from the input
power unit eg. Tractor/motor or engine. From the back
end of the threshing shaft belt and pulley drive is given
and a required RPM is transferred to a shaft mounted on
one of the side of thresher. And from there with belt and
pulley drive rotation is provided to a blower shaft at the
back end of thresher. There are two blowers mounted
one is for suction and throwing chopped waste and
second is for fine cleaning of the output grain.
As the crop to be fed in the feeding hopper , threshing rotor applies
gentle threshing/shelling and press the material to the concave sieve
made from square polish bars resulting separation of grains and
covers. From there onwards grains fall on reciprocating sieve
chamber and passes through the screen. Wastage ( chopped straws)
can not pass through the holes due to there bigger size and ejected
through powerful blowers and falls away from the operating area.
Small dust particles which passes through screens along with grains
in the reciprocating sieve chamber finally blown by refining fan
mounted on main shaft having air discharge to the final output of
Various parts of multicrop thresher
Double Shaft Thresher Rotor
It is available in two types. This rotor rotates
on two shaft and due to that the speed of the
rotor and fan is proportionally same.
It is very useful for refined chaffing of
• Big Size Sieve
The new model is 30" wide. So there are no
chances of clogging and the cleaning is done
Due to its special design it can be moved to
and fro and up and down even though it is
attached to Thresher.
Rear- Side Blower
This facility helps to throw away residue and
to avoid spoiling tractor's radiator in case of
change in the direction of wind.
Traction Joint Hook
It is specially designed to adjust it up or down
as per requirement.
It is designed in accordance with R.P.M of
tractor. So the speed of the sieve can be
adjusted according to the crop.
Modern design and new arrangement for
feeding corn into the machine. This avoids
chances of accident. No necessity to push
corn into the machine by hands. No injury
is caused while drawing wheat, mustard,
vetch, etc and also has better average.
When to thresh
thresh the corn when:
20-25% grain moisture
80-85% straw colored and
the grains in the lower part of
the panicle are in the hard doe
30 days after flowering
Combination of fan and
Air delivered by first fan
removes lighter materials
Second fan removes heavy
materials by flow airs from
behind parts of the sieves.
Top sieves with large holes
remove larger straw particles
Bottom sieves with smaller
holes remove small seeds (e.g.
Losses during threshing
Separation loss or “blower loss” = mature grains that are
mixed with straw or chaff during the cleaning operation.
Scatter loss = mature grains that are scattered on the ground
during the threshing and cleaning operation.
Threshing loss = mature grains that remain attached to the
panicle in the straw after completion of the threshing operation.
High threshing efficiency will lead to low threshing loss, and vice
Recommendations for optimizing quality
Threshing at the right time and moisture content
Avoid stacking the cut crop in the field
Avoid delays in threshing after harvesting
Use the proper machine settings when using a threshing
Clean the grain properly after threshing
Avoid delay in drying after threshing
Tips for manual threshing
Thresh as soon as possible
Hand thresh at lower
Place a large canvas under
the threshing frame to
minimize shatter loss
Tips for machine threshing
Thresh as soon as possible after
Level the thresher
Set machine correctly
drum speeds in thresher
air flow in the cleaner
angle in the cleaner sieves
Setting threshing drum speed
Always adjust the thresher
For peg-tooth drums the drum
tip speed should be about 12-16
m/sec (see Table for correct
Higher speeds result in higher
grain damage and de-hulled
Lower speeds increase the
amount of non-threshed grain
and result in grain loss. Lower
speeds also decrease the
throughput of the thresher.
Tip speed (m/s) for drum diameters of
Setting concave clearance
For most threshers clearances
between peg-teeth and concave
should be about 25mm.
Smaller clearance increases
grain damage and might lead to
clogging of straw.
reduce threshing efficiency.