Design And Construction Of Corn / Maize Threshing Machine

Project and Seminar Material for Mechanical Engineering ME

Project and Seminar Material for Mechanical Engineering ME


A machine for corn threshing is highly and greatly needed to consistency of usage of corn in local and international levels. With regards to this indispensable needs, a corn threshing machine is designed which operates to remove the corn grains and leaving the cobs intact. In attainment to this design objective and aims, a proper considerations was given to the machinability factor which includes installation, simplification, durability, choice material, machine, low costly and prolonged life span when operate with high utilization with minimal down fine.

The design details are given which includes such items as materials and their characteristic adaptation methodology, the part relation with the whole device and the effect of the finished product upon which an inquisitive mine can make collection of fact in future which related to this project.

Table Of Content

Preliminary Page(s)

  • Title page
  • Certification
  • Dedication
  • Acknowledgement
  • Abstract
  • Table of content

Chapter One

1.0 Introduction

  • 1.1 Statement of the problem
  • 1.2 Significance of the study
  • 1.3 Objective of the study
  • 1.4 Scope of the study

Chapter Two

2.0 Literature Review

  • 2.1 Features of the corn Threshing Machine
  • 2.2 How the threshing Machine Works
  • 2.3 The Kind of Corn Threshing Machine to Be produced
  • 2.4 Farming Process
  • 2.5 Modern Development of the Machine
  • 2.5.1 In Europe and Americas
  • 2.6 Thresher Maintenance
  • 2.7 Storage of the Threshing Machine

Chapter Three

3.0 Design Consideration

  • 3.1 Equipment Used for the Construction
  • 3.2 Design Analysis
  • 3.2.1 Shaft Design
  • 3.2.2 Shaft Analysis
  • 3.3 Pulleys
  • 3.3.1 Determination of the Velocity of pulley
  • 3.3.2 Torque Exerted to the Driving Pulley
  • 3.3.3 Torque Exerted to the Driven Pulley
  • 3.3.4 Centrifugal Stress Induced in the Run of he Pulleys
  • 3.35 Weight of Pulley
  • 3.4 Belt Design
  • 3.4.1 Calculation of Length of Belt
  • 3.4.2 Determination of the Angle of Contact of the Belt
  • 3.4.3 Evaluation of the Tension in the Belt
  • 3.5 The Main Frame
  • 3.6 Determination of Weight of Threshing Drum
  • 3.7 The prime Mover
  • 3.7.1 Electric Motor
  • 3.7.2 Rating of Electrical Motors
  • 3.7.3 Power Required to Operate the Machine
  • 3.8 Bearing Selection
  • 3.9 Spherical of 10 Gram of Maize
  • 3.9.1 Determination of Angle of Repose
  • 3.9.2 Screen
  • 3.9.3 Key

Chapter Four

4.0 Determined Qualities

  • 4.1 Cost of Analysis of the design
  • 4.2 Test procedure
  • 4.3 Test Running with Corn
  • 4.4 Performance Efficiency of the Machine
  • 4.5 Machine Capacity
  • 4.6 Safety Precaution during use

Chapter Five

5.0 Conclusion and Recommendation

  • 5.1 Conclusion
  • 5.2 Recommendation
  • References
  • Appendix

Chapter One

1.0 Introduction

Grains, according to Okaka (1997) are fruits of cultivated grasses belonging to the monocotyledonous family, Gramineae. The principal cereal grains of the world include wheat, barley, rye, sorghum, rice and maize. The last has become a popular staple in West Africa. Maize is another world’s most versatile seed crop. Its cultivation originated from Europe but was soon brought to Africa by explorers early in the sixteenth century. Within hundreds of years, it was well established as a staple food in areas around the north and south shores of Mediterranean Sea.

In later years, maize cultivation spread widely into Africa down to Nigeria as well as many parts of Asia all at the same span of time. Its production in the southern states of the United States of America also expanded greatly just as it was in Africa and Asia (Adaokoma 2001). The use of sticks for threshing was predominant in the pre-historic era. In Egypt, livestock was earlier employed for threshing out grains after which it was winnowed. In Palestine, threshing sledge was used 3,000 years earlier. In Nigeria, maize was threshed originally by bare hands. Other popular method was the use of pestle and mortar (www journal .au. edu).

This method is still used in the rural areas today. The above methods became unsatisfactory because of their low output, tediousness and their requirement of extra strength. According to Kaul and Egbo (1985), the performance of a thresher depends upon its size, cylinder speed, cylinder concave clearance, fan speed and the sieve shaker speed. Oni and Ali (1986) reported that the factors influencing thresh ability of maize in Nigeria are field drying, maize varieties, ear size cylinder speed and feed rate. The properties of the crop that affect the thresher performance are crop variety, shape and size, hardness of the seed, the moisture content of the seed and the density.

The major steps involved in the processing of maize are harvesting, drying, de-husking, shelling, storing, and milling. For the rural farmers to maximize profit from their maize, appropriate technology that suites their needs must be used. The processing of agricultural products like maize into quality forms not only prolongs the useful life of these products, but increases the net profit farmers make from mechanization technologies such products. One of the most important processing operations done to bring out the quality of maize is shelling or threshing of maize.

In Nigeria, maize constitutes the staple food of large chunk of the populace. It is also responsible for about 60% by weight of most of livestock feed formulations. Peasant farmers are responsible for more than 70% of the maize produced annually while large scale commercial farmers constitute the remaining 30% (Adewumi, 2004). The problems of post harvest processing and storage of agricultural produce are well documented and various approaches are being employed in tackling it. For maize, one of its post harvest challenges is shelling. Kaul and Egbo, 1985 reported that maize harvested are traditionally shelled by hand or by beating sacs stuffed with maize cobs with wooden flails.

These traditional methods of shelling maize are time wasting, hazardous and associated with lots of drudgery. They also described shelling as a process of repeated pounding or dragging of plant mass over a surface through an aperture. Akubuo, 2003 described the use of pestle and mortar as a process by which the dry maize is put into the mortar and pestle is used to hit the maize with impact forces. A considerable quantity of shelling is achieved per time but the amount of grain damage is high with low cleaning efficiency (Ologunagba, 2003).

There have been various means of shelling starting from the traditional pestle and mortar to the various mechanical and electro-mechanical devices. The use of ‘cone’ sheller was reported by Kaul and Egbo, (1985), the sheller consists of a cone with three to four lines of serrated ribs. The dehusked cob is rotated in the cone by one hand while the Sheller is held in the other hand rotating the cob against the internal rib of the Sheller to detach the grain from the cob. Adewale, et al (2002) and Adegbulugbe, (2000) established that shelling process is a function of moisture content.

It is easier to shell maize dry than wet. Adewale et al (2002) also reported that the local techniques of shelling and winnowing of shelled maize is grossly inefficient judging by the serious bruises encountered by the crops. There are many types of maize shellers, but the motorized shellers are either imported or locally fabricated by local welders who have no knowledge of both the machine and crop parameters suitable for optimum performance of the shelling machines (Adewumi, 2004). Maize can also be dehusked and shelled but this is with a lot of kernel damage at the end of the processing operation (Adesuyi, 1983). Other types of devices used for shelling mechanism are cross flow rasp bar, axial flow rasp bar and spike tooth cylinder. A spike tooth cylinder is more positive in feeding than rasp bar cylinders with the added advantage that, it does not plug in easily. While rasp bars are easier to adjust and monitor and are relatively simple to operate and durable. The efficiency of shelling machines varies from one machine to the other as affected by some factors like the crop moisture content, feeding rate, shelling mechanism and the concave cylinder clearance (Adewale et al, 2002).

1.1 Statement Of The Problem

Traditional shelling methods do not support large-scale shelling of maize, especially for commercial purposes. Locally in Nigeria, the region that is the highest producer of Maize is the northern part of the country. It was observed that most shelling of maize was done by hand shelling. Hand shelling take a lot of time, even with some hand operated simple tools. It was also observed in the study area, Nasarawa State, most mechanical shellers were designed for multi-grain threshing or shelling, which causes great damage to the maize seeds besides breaking the cob to pieces.

The available sheller locally, were equipped with rotating threshing drum with beaters or teeth, which cause damages to the seed. Besides, the cost of purchasing such shellers were high for the poor rural farmer and therefore necessitated the design of low cost system that will be affordable and also, increase threshing efficiency with reduced damage done to the seed.

1.2 Significance Of Study

Many farmers grow maize but could not afford the cost of acquiring some of the imported threshing machines because of their cost, and such people resort to manual means of threshing which results into low efficiency. This work is necessary as it was aimed at constructing the machine that shells maize and separates the cob from the grains. Since the machine was constructed from locally available materials and its cost is very low and affordable, farmers can now adopt this kind of machine for their farming improvement.

1.3 Objective Of The Project

The specific objectives of the work were to design, construct, and test a low-cost maize sheller. To evaluate the efficiency of the maize sheller. To use the maize sheller in establishing an agro-processing centre for rural farmers.
This project work is to achieve the following:

  1. To improve the aesthetical standard as compared with other locally made corn threshing machine
  2. To reduce the hardship encountered by people who cannot afford the cost of buying an imported threshing machine.
  3. To have a more sophisticated and integrated corn threshing machine that can compete favourably with imported ones.
  4. To minimize the farmers’ cost of securing labourers for manual corn threshing
  5. To aid farmers make their produce available for people’s consumption and company use and on time too.

1.4 Scope Of The Study

This project involves the design and construction of a system with a hopper which is designed to be fed in a vertical position and the shaft design which has a threshing tool attached to it (by welding) at two opposing sides and a pulley mounted on it, which is used for threshing of corn effectively.

The work includes feasibility studies, planning, design, applying related calculation, material selection and procurement constructional analysis and preparation of components of the threshing and subsequent assembly.

1.5 Brief History Of A Corn Threshing Machine

Corn threshing machine was first inverted by a Scottish mechanical engineer Andrew Meikle for use in agriculture (1786). It was devised for the separation of grains from stalks and husks. For thousands of years, corn was separated by hand which was very laborious and time consuming. Mechanization of this process took much of the drudgery out of farm labour.

For the early social impacts, the swing rivots in the UK were partly a result of the threshing machine. Following years of war, high tasks and low wages, farm labours finally revolted in 1830. These farm labours had faced unemployment for a number of years due to the widespread introduction of the threshing machine and the policy of enclosing fields. With fewer jobs, lower wages and no prospects of things improving for these workers, the threshing machine was the final straw; the machine was to place them on the brink of starvation.

Early threshing machine was hand-fed and horse-powered. They were small by today’s standards and were about the size of an upright piano (Stuar. T. Macdonald). Later machines were steam-powered, driven by a portable engine or fraction engine. Isaiah Jennings, a skilled inventor, created a small thresher that doesn’t harm the straw in the process. In 1834, John Avery and Hiram Abial Pitts devised significant improvements to a machine that automatically threshes and separates grain from chaff, freeing farmers from a slow and laborious process (1881 household cyclopedia). Since the invention of this machine, Mr. Meikle and others have progressively introduced a variety of improvement, all tending to simplify the labour, and to augment the quantity of work performed.

When first erected, though the grain was equally well separated from the straw, yet as the whole of the straw chaff and grain were indiscriminately thrown into a confused heap, the work could only with propriety be considered as half executed. By the addition of raders, or shakers, and two pairs of farmers all driven by the same machinery, the different process of threshing, shaking and winnowing are prepared for the public market.

1.6 Farming Process

Threshing is just one process in getting cereals to the grinding mill and customer. The wheat needs to be grown, cut, stroked (shocked, bundeled), threshed, the de-chaffed, straw baled, and then the grain hauled to a grain elevator.

For many years, each of these steps was an individual process requiring teams of workers and many machines. In the steep hill wheat country of Palouse in the Northwest of the United States, steep ground meant moving machinery around was problematic and prone to rolling (Isaiah Jennings, friction match threshing machine).

To reduce the amount of work on the sidehills, the idea of combining the wheat binder and thresher into one machine, known as a combine harvester was conceived. About 1910, horse pulled combines appeared and became a success. Later, gas and diesel engines appeared with other refinements and specifications (Ridley John 1806-1887).

Chapter Five

Conclusion And Recommendation

5.1 Conclusion

The design and construction of the corn threshing machine has been completed. Grains loss and mechanical visible damage have been very minimal. Performance test has revealed that the efficiency of the machine is 73.12 . The machine threshes 36.69kg of maize within an hour. The machine can either be powered by an electric motor or engine (diesel or petrol).

The relevance of this machine in our present day life cannot be overemphasized because of the increasing population and high demand for maize for domestic and commercial purposes. It is necessary that an affordable maize threshing machine should be made available for farmers.

The design has been found to be most economical having the optimum technical and operational characteristics, such as productivity, replacement ability, service life, simplicity, ease in operation and safe maintenance.

5.2 Recommendation

This study recommends that the production of this corn threshing machine in commercial quantity should be encouraged with a view of increasing large-scale shelling of maize, especially for commercial purposes as it will be more affordable than the imported ones.

Furthermore, the large scale production of this machine as stated in one of the objectives will minimize the farmers’ cost of securing labourers, so it is therefore recommended that the machine should be distributed across the country in order to enhance productivity.

Also, this work will reduce the dependency of imported maize threshing machine, in the sense that imported ones are more expensive.

Lastly, more research should be carried out on the machine, as to improve the efficiency. Meanwhile, the results obtained during test were impressive and gave hope for further research.

Project Material Download

5,000 5000

The Complete Material Will Be Sent to You in Just 2 Steps

Quick & Simple…

Step One Purchase

Make Payment (Through Transfer) of ₦5,000 to Any of the Account Below

Access Bank PlcAcc No: 0811003731
Samphina Academy
Current Account
Zenith BankAcc No: 1225513212
Samphina Academy
Current Account

Or CLICK HERE To Pay With Debit Card

CLICK HERE To Purchase Material ($15)
Make Payment of 120 GHS to 0553978005 | Douglas Cloud Osabutey | MTN MoMo

Step Two Purchase

Send the Following Details on WhatsApp ( 08143831497) After Payment

  1. Payment Details

  2. TOPIC: Design And Construction Of Corn / Maize Threshing Machine

The Complete Material Will Be Sent To You On WhatsApp After Receiving Your Details
T & C Apply

  Contact Our Help Desk

Need a Different Topic? Perform a Quick Search

List of Related Works

Click on Any Topic to Preview the Content

Samphina Academy

Samphina Academy is an Online Educational Resource Center that is aimed at providing students with quality information and materials to aid them in succeeding in their academic pursuit.