Design And Fabrication Of A Mechanical Sieve Shaker

Description

ABSTRACT

This work is on the fabrication of a mechanical sieve shaker suitable for sand grain size analysis in the foundry industry. It consists of a set of stacked sieves mounted on a shaker unit, which is agitated by means of two bevel gears that produce rotary motion of the sieves. Several fabrication techniques such as welding, machining, etc., are adopted for the fabrication of the machine. Dry clay-free sand sample was tested with the machine for operational effectiveness and particle size distribution. The result shows that the machine is suitable for sieving sand grain size of the order of 0.1 to 1.0mm but cannot sieve larger particles such as gravel. The fabricated mechanical sieve shaker performed well with high sieving efficiency, reliability and durability. The particle sieving efficiency ranges from 92 to 97%.

TABLE OF CONTENTS

COVER PAGE

TITLE PAGE

APPROVAL PAGE

DEDICATION

ACKNOWELDGEMENT

ABSTRACT

CHAPTER ONE

INTRODUCTION

1.1      BACKGROUND OF THE PROJECT

• PROBLEM STATEMENT
• AIM/OBJECTIVE OF THE PROJECT
• ADVANTAGES OF THE PROJECT
• APPLICATIONS OF THE PROJECT
• BENEFIT OF THE PROJECT
• LIMITATION OF THE PROJECT

CHAPTER TWO

LITERATURE REVIEW

• REVIEW OF THE STUDY
• REVIEW OF RELATED STUDIES
• SIEVE ANALYSIS

CHAPTER THREE

MATERIALS AND METHODS

• MATERIALS
• TOOLS AND INSTRUMENTS
• FABRICATION
• EXPERIMENTATION AND PERFORMANCE ANALYSIS

CHAPTER FOUR

RESULT ANALYSIS

4.1     RESULTS AND DISCUSSION

CHAPTER FIVE

• CONCLUSION
• REFERENCES

CHAPTER ONE

1.0                                             INTRODUCTION

1.1                               BACKGROUND OF THE STUDY

The quality of product achieved by sand casting is partly a function of the kind of sand used during moulding. Quartz and other silica rock particles are the source of silica sand which is commonly used in moulding (Chipil and Basal, 2014). However, the natural sand does not possess the actual properties needed for moulding. It consists of different shaped and sized particles (particle size distribution), responsible for important physical and mechanical properties of the product (Hagen et al, 1987).

If the particle size distribution changes during manufacturing process, then the quality of the finished product will also change. Hence only a continuous monitoring of the particle size distribution can maintain constant product quality (Ayodeji et al, 2014; Scott and Tim, 2015).

In order to determine the particle size distribution of sand, sieving is employed. Sieving is a unit operation carried out by allowing solid particles of different sizes to pass through the pores of an orderly arranged set of stacked sieves in a manner of the particle sizes and shape (Abubakar et al, 2015).

Numerous studies (Keshun, 2009; Ujam and Enebe, 2013; Christopher and Robinson, 2014; Ayodeji et al, 2014) reveal the fabrication of electrically operated sieving machines, in which agitation and vibration of the sieves are accomplished via electric motor. The sieves are vibrated and rotated about its axis. These designs equally work in similar manner with the Electromagnetic sieve (Ujam and Enebe, 2013; Smith, 1990), in which a combined action of electricity and magnetism is utilized to operate the sieves. The sieving operation is achieved by either rotary or vertical motion, or a combination of these thereof.

In other designs (Simolowo and Adeniji, 2011; Oladeji, 2012; Eccless and Ekwue, 2008), vibrating the sieves may be achieved by means of pulley and belt drives operated by electric motor. The pulley system is supported on a shaft mounted on bearings that facilitate both lateral and vertical oscillation with amplitude of 32mm in each direction. A special type of the sieve shaker is the Pedal driven type (Abubakar et al, 2015; Smith, 1990) wherein, sieving is achieved by driving the set of sieves by a chain – sprocket mechanism using pedals. The sieves vibrate vertically. In all these designs, the sieving method can be vibratory sieving, horizontal sieving, vertical sieving, tap sieving, air jet sieving or a combination of two or more these methods (Jacob et al, 2015; Oladeji, 2012). In the vibratory sieving method, the sample is thrown upwards by the vibrations of the sieve bottom and falls back down due to gravitation forces (Ayodeji et al, 2014). The tap sieve shaker sieves the sample via a horizontal circular movement superimposed by a vertical motion generated by a tapping pulse (Rajput, 2010).   Air jet sieving involves the use of only one sieve in which the material on the sieve is moved by a rotating jet of air (Adebayo, 2014).

In this work, a mechanical sieving machine that uses bevel gears to sieve sand grains is fabricated and tested for operational effectiveness and sand particle size analysis. The machine does not require any input power source for its operation as it is manually operated. It is proposed to be used for experimental research purposes even in remote areas where power supply is a problem.

1.2                                      PROBLEM STATEMENT

Electrical operated sieve shaker uses electricity to operate but looking at the erratic situation of power supply in developing countries such as Nigeria, using electric powered sieve shaker machine becomes a problem. it was because of this problem that a mechanical sieve shaker was built. The machine does not require any input power source for its operation as it is manually operated. The machine was made to be used in aremote areas where power supply is a problem.

1.3                            AIM / OBJECTIVE OF THE STUDY

The main aim of this work is to build a mechanical device that will expose the sample to all the openings in a sieve in a manner that will expedite the passing of particles smaller than the openings. The objectives are:

i.                   To make sieving of particles easy

ii.                 To uses bevel gears to sieve sand grains

iii.              To be able to build a machine for grading the grain size to detach stones from sand from grains.

1.4                             ADVANTAGES OF THE PROJECT

• The vibrating operation is
• It is manually operated
• Simple in construction and easy to
• It is compact in size and less weight.

1.5                            APPLICATIONS OF THE PROJECT

• It can be utilized for separation of mass produced different types of nuts in a single turn and also other solid mixtures with different sizes of mesh
• Different types of nuts can be separated which depends on mesh size
• It can be used for paddy separation with the involvement of fan at the base of
• Now days, separation of different sizes of solid material is need of hours, this project can be used for separation of different sizes of solid only by changing mesh of required
• Substance industry: resin, pigment, industrial medicine, cosmetic,
• Foodstuff industry: sugar powder, starch, salt, rice noodles, milk powder, soybean milk, egg powder, sauce,

1.6                                  BENEFIT OF THE PROJECT

Determining the particle-size distribution of a soil helps the engineer, geologist, or an agriculturist to understand many soil properties such as how much water, heat, and nutrients the soil could hold, how fast water and heat will move through the soil, and what kind of structure, bulk density and consistence the soil will have. Particle size distribution of soils affects soil credibility and soil compaction since soils with uneven particle size distribution are expected to pack more closely than those with uniform distribution. Particle size distribution of soils is normally determined by wet sieving or dry sieving. While wet sieving is used to determine the proportion of stable aggregates resistant to water disruption during rainfall, dry sieving is utilized mainly to relate particle sizes to soil erosion by wind.

Determining particle size distribution of a soil by hand is a very tedious process, hence, the use of mechanical shakers which makes the process a much simpler one.

1.7                                             LIMITATION OF THE PROJECT

One distinct disadvantage of present commercial mechanical shakers is that they are very expensive due to complicated operative process and only sieve one stack of soil at a time. This makes the analysis of several soil samples a very time consuming process.