Rotary Model Corn Sheller Design to Reduce Workload and Increase
Productivitys
A. A. Ngurah Bagus Mulawarman
and I Ketut Gde Juli Suarbawa
Mechanical Engineering Department, Bali State Polytechnic, Jalan Kampus Bukit Jimbaran,
Kuta Selatan, Badung, Bali, Indonesia
Keywords: Corn Shelle Machiner, Workload, Productivity.
Abstract: The current working process of corn kernels is removed by crushing manually by hand so it is very tiring and
low productivity. To speed up the shelling process, it is necessary to design a model of the corn sheller which
is expected to be able to remove the corn kernels from the cob. The method used in this rotary method of
removing corn kernels uses a prime mover in the form of an electric motor which is connected to the drive
shaft through pulleys and belts that will process the release of corn kernels. Thus, this study is aimed to
investigate the ability of shelling process to reduce the workload and increase work productivity. Corn sheller
machine with rotary method with dimensions of 950 mm high, 755 mm wide and 750 mm long using a 0.25
HP electric motor as the main driver. This machine has 2 functions, namely as a corn kernel thresher and corn
kernel size separator. In the corn kernel threshing section there is a sheller knife with a diameter of 76.2 mm
and a length of 600 mm. The corn kernel separator is slightly conical in shape with a diameter of 250 mm on
one side and 200 mm on the other. This is so that the corn can move from the side that is 200 mm in diameter
to the side that is 250 mm in diameter. The corn kernel sheller and separator uses a 1” diameter shaft. This
tool is also equipped with a blower that functions to clean corn kernels from the corn cob skin that comes off
during shelling. Based on test results, the time for shelling corn seeds using this corn sheller machine takes
an average of 8.30 minutes for 50 kg of corn cobs. While the time required for the manual shelling process
for 50 kg of corn cobs is an average of 56.73 minutes. Work productivity by using shelling machine increased
by 588% from 0.0084 manual shelling process and work productivity increased to 0.051 using corn sheller
machine.
1 INTRODUCTION
Shelling is the process of separating the cob from the
corn kernels. The corn shelling process is almost the
same as the rice shelling process, which is to separate
the seeds from the attachment site. Corn is attached to
the cob, so the seeds and cobs must be separated.
According to Aqil, M. (2009), Hadijah (2010) and
Bunyamin et al (2015) an increase in corn production
that is not followed by good post-harvest handling
causes the opportunity for seed damage due to
mishandling to reach 12-15% of the total production.
Furthermore, among all post-harvest stages, the shell
segment has the highest probability of losing its yield
which reaches 8% so that this process is considered a
critical process in post-harvest handling. The process
of shelling corn manually causes fatigue to occur
quickly in farmers. According to Tarwaka (2004) and
Tarwaka (2014) fatigue is a body's protective
mechanism so that the body avoids further damage so
that recovery occurs after rest. To avoid the level of
fatigue, it is necessary to avoid a static work attitude
and strive for a more dynamic work attitude. This can
be done by changing a static work attitude into a more
varied or dynamic work attitude, so that blood and
oxygen circulation can run normally throughout the
body.
The peeling process is carried out by farmers
manually using hands, so it takes a long time. Manual
shelling of corn produces small amounts of shelled
corn, namely 0.1 kg per minute. The use of hands for
the shelling process causes corn farmers to easily
experience fatigue and complaints of sore hands.
In an effort to overcome this, a rotary model corn
sheller machine was designed and built to speed up
the shelling process and reduce fatigue so that work
productivity increases.
Mulawarman, A. and Suarbawa, I.
Rotary Model Corn Sheller Design to Reduce Workload and Increase Productivitys.
DOI: 10.5220/0010954500003260
In Proceedings of the 4th International Conference on Applied Science and Technology on Engineering Science (iCAST-ES 2021), pages 833-836
ISBN: 978-989-758-615-6; ISSN: 2975-8246
Copyright
c
2023 by SCITEPRESS – Science and Technology Publications, Lda. Under CC license (CC BY-NC-ND 4.0)
833
2 METHODOLOGY
2.1 Research Design
T This research is a one-short case study with a pre
and post test design which was carried out by
observation of the corn shelling work process
(Corlett, 2005) and (Wilson, 2015). Chart can be
described as follows:
R Æ P0 Æ PI
Figure 1: Research design.
Information:
R = Random sample.
P0= the result of the pre-test experimental unit.
PI = the result of the post-test experimental unit.
2.2 Research Variable
The variables to be measured in this study include:
(1). workload as measured by pulse of rice before and
after work; (2) complaints of fatigue and skeletal
muscles before and after work; (3) work productivity
after work by comparing work pulse (beats per
minute) with the number of products produced (kg)
during working time (minutes). The measurement of
variables number (1) to number (3) is the information
data of the initial condition and the final condition
which is then compared to determine the comparison
before using the corn sheller machine and after using
the corn sheller machine.
2.3 Data Analysis
The design data for the corn sheller machine with the
rotary method is calculated based on the capacity
requirement of 50 kg of corn, then the shelling
system, the ergonomic construction of the machine
seat. The test data before the use of the sheller
machine and after the use of the sheller machine
includes data on working time/length of work,
workload and work productivity which will then be
analyzed descriptively to obtain conclusions.
3 RESULTS AND OUTCOMES
3.1 Machine Design Results
The corn sheller machine is designed with an electric
motor drive, the basic concept is to utilize the rotary
motion or rotation of an electric motor to rotate a
modified shaft for threshing corn kernels. The
rotation of the electric motor is transmitted by the
pulley and the V-belt. Furthermore, the corn will be
inserted through the funnel attached to the frame, the
corn will automatically be crushed and run along the
track, until the end of the corn kernels is flat apart
from the cob.
Figure 2: Machine design results.
Caption:
1 Engine frame 13 Bottom side cover
2 Bearing 14 Left side cover
3 Filter 15 Up Cover
4 Shell knife 16 Bottom cover
5 Axis 17 Motor cover
6 Pulley 12” 18 Blower
7 Electric motor 19 M12 x 30 mm
8 Pulley 2.5”
20
M8 x 35 mm
9 Pulley 3” 21 M6 x 12 mm
10 Pulley 10” 22 M4 x 8 mm
11 V-Belt 23 Pulley 7”
12 Side Up Cover
3.2 Work Principle
Corn sheller machine with electric motor drive, the
basic concept is to utilize the rotary motion or rotation
of the electric motor to rotate the modified shaft for
threshing corn kernels. The rotation of the electric
motor is transmitted by the pulley and the V-belt.
Next, the corn will be inserted through the funnel
attached to the frame, the corn will automatically be
crushed and run along the track, until the end of the
corn kernel is flat regardless of the cob.
Corn kernels will fall down to the size separator,
when they fall, the corn seeds will be blown by the
wind from the blower that has been installed in the
frame, which causes the cob flakes to fly and separate
from the corn kernels. So later that goes into the size
separator only the corn kernels. The size separator
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rotation also utilizes the rotation of the same electric
motor that is connected to the pulley and V-belt.
3.3 Machine Specification
This corn sheller machine is a machine that uses an
electric motor as its borer and electricity as its energy
source. With this machine, the corn shelling job
becomes more effective and efficient compared to the
manual method. Advances in technology are
increasingly rapidly creating a lot of shelling
machines in the market that are very useful for
farmers.
Figure 3: Corn Sheller Machine.
The sheller cylinder is equipped with a plate that
functions as a pitcher thrower. This machine is also
equipped with a sieve assembly to separate shelled
corn from corn cobs and cobs. The sifter can be
adjusted so that it can press the corn and husks. Its
main components include a cylindrical which has a
tooth that is not the same height. This makes shelling
easier and separating the shelled corn from the cobs.
The Machine Specifications include:
• Capacity: 360 kg/Hour.
• Size: Height 950 mm, Width 755 mm and
Length 750 mm
• Machine Material: Steel Plate.
• Mover: Electric motor.
• Sheller knife: Diameter 76.2 mm and Length
600 mm
• Power (Power):0.25 HP.
• Machine Dimension Frame: Iron elbow
3.4 Machine Testing
The test was carried out 5 times to find out the time
needed to complete 1 shelling of 1 corn. The large
seeds weigh about 1000 grains ranging from 283.87
to 298.83 g while the small seeds are 219.20 to 239.17
g. In one cob, the average weight of the seeds reaches
223 grams. While the cob weight itself is an average
of 242 grams.
1. In the test of sample A, the corn was tested 5 times
with an average corn diameter of 33 mm, a
minimum corn length of 125 mm and a maximum
of 130 mm with a total corn weight of 50 Kg.
2. In the test of sample B, the corn was tested 5 times
with an average corn diameter of 36 mm and a
minimum corn length of 130 mm and a maximum
of 135 mm with a total corn of 50 Kg.
3. In the test of sample C, the corn was tested 5 times
with an average corn diameter of 38 mm and a
minimum corn length of 135 mm and a maximum
of 140 mm with a total corn of 50 Kg.
The results of sample testing on the manual peeling
process and the shelling process with the help of a
shelling machine include:
1. In the process of shelling corn manually by hand
by farmers, the average shelled corn is 23.97 kg
of the total weight of corn with an average of 50
kg on the cob, and the length of the picking
process is an average of 56.73 minutes.
2. In the process of shelling corn manually with a
sheller machine by farmers, the average shelled
corn is 24.13 kg of the total weight of corn with
an average of 50 kg on the cob, and the length of
the picking process is an average of 8.30 minutes.
3.5 Corn Seed Shelling Work
Productivity
Productivity testing of corn kernel shelling can be
calculated by the formula:
=
• Output is weight of shelled corn produced
(kg)
• Input is weight of corn to be shelled (kg)
• Times is times shelling process (minutes)
After the calculation process is obtained, Manual
shelling work productivity is 0.0084 and work
productivity in the machined shelling process is
0.0580. Based on the acquisition of work
productivity manually with a corn sheller machine, it
Rotary Model Corn Sheller Design to Reduce Workload and Increase Productivitys
835
was found that there was an increase in work
productivity of 588% or a ratio of 1:6 due to the use
of a corn sheller machine.
4 CONCLUSIONS
Based on the discussion that has been carried out, the
following conclusions can be drawn:
1. Corn kernel sheller machine with rotary method
with dimensions of 950 mm high, 755 mm wide
and 750 mm long uses a 0.25 Hp electric motor as
the main driver. This machine has 2 functions,
namely as a corn kernel thresher and corn kernel
size separator. In the corn kernel threshing section
there is a sheller knife with a diameter of 76.2 mm
and a length of 600 mm. The corn kernel separator
is slightly conical in shape with a diameter of 250
mm on one side and 200 mm on the other. This is
so that the corn can move from the side that is 200
mm in diameter to the side that is 250 mm in
diameter. The corn kernel sheller and separator
uses a 1” diameter shaft. This tool is also equipped
with a blower that functions to clean the corn
kernels from the corn cob skin that comes loose
during shelling.
2. Based on the test results, the time for shelling corn
seeds using this sheller machine takes an average
of 8.30 minutes for 50 kg of corn cobs. While the
time required for the manual shelling process for
50 kg of corn cobs is an average of 56.73 minutes.
3. Work productivity by using a shelling machine
increased by 588% from 0.0084 by hand shelling
process and work productivity increased to 0.058
by using a corn sheller machine.
ACKNOWLEDGEMENTS
The authors would like to thank the department of
research and community service center Bali State
Polytechnic and the Ministry Of Education and
Culture of Indonesia for the financing of this research.
REFERENCES
Aqil, M. (2009). Improvement of corn seed quality through
optimal nutrient management. Prosiding Seminar
Nasional Serealia 2009.
Bunyamin Z, Fahdiana Tabri, dan M.Akil. (2015). Nutrient
management for hybrid maize on dry land in Gowa
District. Prosiding Seminar Nasional Serealia 2015.
Corlett N, (2005). Evaluation of Human Work (3rd ed.).
Taylor & Francis Group ISBN 0415267579
Hadijah A. D. (2010). Increasing corn production through
the implementation of integrated crop management
innovation. Iptek Tanaman Pangan, Vol 5 No.1.
Tarwaka, et al. (2004). Ergonomics: For Occupational
Safety, Health and Productivity. Surakarta: Uniba
Press.
Tarwaka. (2014). Occupational Health and Safety: OHS
Management and Implementation in the Workplace.
Surakarta : Harapan Press.
Wilson,J,R, and Sharples, S (2015). Evaluation of Human
Work (3rd ed.). CRC Press; 4th edition (April 16, 2015)
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