ABSTRACT

Man’s impact on global environment system especially in the area of dust extraction is now at a scale where it is disrupting.  These dust extractors varies in major ways.

The environmental degradation is, in turn contributing to health threat in this part of the globe.  Unfortunately most factories, workshops which suppose to posses these machines for dust extractions a re not having them thereby making dust a very dangerous threat to man. 

Due to this ugly development it, is obvious that these factories and workshops can do little or nothing to protect our environment from this poor state.  It is therefore necessary that all and sundry should join the crusade of eradicating dust from our environment thereby making it clean.  Although before now people have tried to contribute their own quota in seeing to the end of the menace, get lack of interest, finance has posed a hindrance to the realization of this achievement.

In view of the above, we deemed it necessary that such a machine should be constructed to the Mechanical Engineering workshop to eradicate dust and thereby make the workshop environment clean and fit for students practical activities.

  The realization of this work started from our supervisor who conceived the idea which we saw as a need, and then we defined the need and synthesized it, evaluate and came to a conclusion.

The synthesis led us to drawing board by sketching and drawing to scale after which the design required was chosen.  Fabricated and parts put together to form what we called a dust extractor.

CHAPTER ONE

 INTRODUCTION

Dust is a serious health hazard especially to the respiratory system.  It can have a cumulative effect eventually resulting in permanent damage to the health. Fine dust is the most dangerous and the most difficult to get rid off.  The sharing and the large particles of dust are not much of a problem as most of it falls to the floor quickly and lungs have a built in mechanism which can eject relatively large particles.

The dust particles that causes damage are normally in the range of 0.2 to 5 micron in size (a micron is one thousand of a millimeter) and so small as t o be invisible to the naked eye.  They can remain suspended in the air for hours.  Even if one cannot see any dust, the atmosphere may still be harming ones lungs.  One is likely to breath 8 to 10 cubic meters of air during and 8 hour working day most especially those working in the engineering workshops that has to do with metal drilling (drilling, shaping etc) drugs manufacturing industry, paint industry and food processing industry.

If the dust in the air average out of 5 mg per cubic meter during that period, then you will suck in 50gm (2 ounces0 of dust.  Most of this w ill be dealt with by the body’s own dust defence mechanism the nasal hair and mucus lined walls of the air ways leading to the lungs will swallow most of it.  Only a very tiny percentage of the dust is permanently trapped in the lungs but it is this which causes the damage.

Dust from some wood can cause skin complaints such as dermatitis.

Dust Extractors:   With a small dust extractor couple with the respirator to give a primary protection.  You must not need a huge powerful machine it w ill help to keep the workshop clean and you can use it with it’s flexible hose to cover up the sharing and remove dust which has settled on surfaces.  Because you have a wood turning lathe you can quickly turn up a wooden adaptor to accept the hose form your domestic vacuum cleaner to give you a handy extension hose.  If you have other wood working machines such as a table saw you can hookup the extractor to them when you need to use them.

EXTRACTING DUST:The fan sucks the air into an oil drum shaped container and then through an internal filter.  These machines usually also make use of the cyclone effect to reduce the load on the filter.  This type of machine is cheaper, takes less space, has superior filtration and has a stronger suction for hovering.  The motor however is very noisy and the airflow is much less than the external bag machine.

The small filter clog quickly reducing he air flow dramatically.  The wood turner really need is a machine which moves a larger volume of air at a lower speed breeze which wafts the fine suspended dust away from the lathe into an efficient filter.

Those extractors setups for paint spraying welding which consist of a large three sided box built around the work area.  Built into the rear of the box in an array of huge powerful fans which sucks all fine dust and fumes through suitably design filters at the rear and recalculate the air.  They work well because they move a very large volume of air.

Another dust extractor BB100, this is a low cost fine dust extractor (performance rating 3) for the hobby workshop.  It is equipped with a 1000 watt vacuum cleaner motor which generates 195 cubic metres per hour of air flow and provides enough suction to cater for even the smallest of power tool inlets.  The two stage filtration system consist of a pleated paper filter, rather like a car filter, surrounding the in let to the vacuum motor and a sub micron paper bag filter which totally encloses the pleated filter.

Largest sized waste, such as planer chippings, fall straight to the bottom of the drum whilst the smaller dust particles are captured by the paper filters.  The paper filters can be easily replaced as necessary whilst the pleated filter can be a vacuum cleaned periodically.  Typical uses for this extractor are small band saws, bench mounted sanding machines and portable power tools such as routers, planners and sanders.  It also serves as a very effective vacuum cleaner for keeping the workshop clean and tidy.

1.1     AIMS AND OBJECTIVE

This project is aimed not only at providing a dust extraction machine in factories and workshops but:

To provide a life equipment in the workshop which can be used for exhibition by students.

To provide a machine (dust extractor0 which could be further modified and improved on, for the extraction of dust from the atmosphere, which can favourably compete with the best in the market.

1.1     ECONOMICS IMPORTANCE OF A DUST EXTRACTOR

1.                 For extraction of dust fro the air
2.                 Locally made dust extractors can be sourced in the market
3.                 Effective dust extraction can only be achieved if handled by an experienced person
4.                 Durability if proper maintenance culture is adopted.

1.3     USES OF A DUST EXTRACTOR
1.                 Can be used in extracting dust from the workshops
2.                 Can be produced and soled to factories thereby serving as a source of income to the producer.
3.                 Reduces disease that could have been contacted from the air through dust.