DESIGN OF A LOW COST MAIZE SHELLER

ABSTRACT

Maize, known in many English-speaking countries as corn, is a grain domesticated by indigenous people in prehistoric times. The Aztecs and Mayans cultivated it in numerous varieties throughout central and southern Mexico, to cook or grind in a process called nixtamalization. The crop spread throughout America and later around the 1250 BC it spread to all corners of the region. Any significant or dense populations in the region developed a great trade network based on surplus and varieties of maize crops. After European contact with the Americas in the late 15th and early 16th centuries, explorers and traders carried maize back to Europe and introduced it to other countries through trade. Maize spread to the rest of the world due to its popularity and ability to grow in diverse climates. The existing methods of corn de-husking in agriculture industry consist of breaking the grains by hand or by using large machinery for shelling, both of which are not effective for a developing economy like Nigeria where farmers have little money for investment. Hence, there is a need for an innovative idea or product that is feasible, safe, cost effective and productive for the Nigerian farmer. The objective of this work is to design and develop an improved maize shelling machine in terms of better time management, affordable cost, portability and mechanical efficiency. The method used involved selecting appropriate materials, and utilization of theories of failure that enable the determination of allowable shear stress on the bearing supports. It features the design calculations necessary for the completion of this work. The production cost of the Maize Sheller is ₦34500 and it is powered by a 5hp electric motor.

TABLE OF CONTENTS

DECLARATIONi

CERTIFICATIONii

DEDICATIONiii

ACKNOWLEDGEMENTSiv

ABSTRACTv

TABLE OF CONTENTSvi

LIST OF FIGURESix

LIST OF TABLESx

CHAPTER ONE

INTRODUCTION1

Background Information1

Problem Statement2

Aims and Objectives of the Study2

Justification of the Study3

CHAPTER TWO

LITERATURE REVIEW4

2.1Maize4

2.1.1Origin, Classification and Botany of Maize4

2.1.2Importance and Uses of Maize4

2.2Maize Shelling5

2.2.1Traditional / Manual Maize Shellers8

2.2.2Mechanized Maize Shellers11

CHAPTER THREE

MATERIALS AND METHODS14

3.1Design Considerations14

3.2Design Analysis and Calculations14

3.2.1Hopper Design15

3.2.2Main Frame Design16

3.2.3Threshing / Shelling Bars Design16

3.2.4Shaft Design17

3.2.5Prime Mover Design21

3.2.6Pulley Design21

3.2.7Belt Design22

3.2.8Groove Dimension Design25

3.2.9Screen Design30

3.2.10Key Design30

3.3Design of all Component Parts31

3.4Machine Description and Operation32

3.5Material Selection for the Machine Components35

CHAPTER FOUR

CONCLUSION AND RECOMMENDATIONS38

4.1Conclusion38

4.2Recommendations38

REFERENCES39

APPENDICES42

LIST OF FIGURES

FIGURETITLE       PAGE

Maize Cobs    2

Maize Shelling by Hand9

Varieties of Hand Maize Shellers Using Different Methods10

Sheet Metal Maize Sheller Forming Jig11

Amizy Maize Sheller11

First Vidhata Shelling Machine12

Second Vidhata Maize Sheller13

Schematic Diagram of the Hopper15

Distributed Weights Acting on the Shaft at Different Sections18

Exploded View of the Maize Sheller Showing Component Parts33

Isometric and Orthographic Drawings of the Maize Sheller34

Conceptual Drawing of the Maize Sheller34

3D Drawing of the Assembly35

LIST OF TABLES

TABLETITLE       PAGE

Comparison of Maize Shelling Methods8

V-belt Horsepower Design Data23

Deep Groove Bearing Selection Factor Design Data25

Recommended Life Value of Bearings Design Data30

Construction Materials for the Maize Sheller and Their Specifications36