Fabrication Of A Pepper Grinding Machine

CHAPTER FIVE
FABRICATION DETAIL OF PEPPER GRINDING MACHINE
5.1 MATERIAL SELECTION
The material to be used for the construction of the grinding machine has to withstand the mechanically applied forces and also to make it heat resistances.
The materials are mentioned  below:
1. MILD STEEL: Gauge to mild steel pipe for the both the spault and the stand. The handle is constructed with mild steel pipe.
2. CAST IRON: This was selected for the grinding plate and grinding stones.
5.2 CONSTRUCTION FOR THE CHOICE OF MATERIALS CAST IRON
i) It has a good resistance to wear and abrasion
ii) it is self  lubricating  because of graphite present in it.
iii) Reasonable Cost
MILD STEEL
I) Its durability
ii) Its ductility
iii) Its ray light in weight
iv)  It has high tensile strength
v) Its malleable that is easy to be bend, cut and fabricated in to different shapes.
5.3 FABRICATION DETAIL
Conclusion work iron of the machine which was the carried out in both the fabrication and machine workshop respectively is enumerated below.
As stated earlier on the machine consists of these four, essential parts namely: The Hopper unit, the crushing unit, the grinding unit and the collection unit.
The Hopper Unit: The construction of the hopper was carried out by using mild steel metal of 3mm thickness.
It was first marked out with a steel rule and scriber and then all the required panel line steps and size of (360mm) for the two parts by the use of guillotine (power cutting machine). They are then joined together by electric type of welding due to the thickness of the metal.
The Crushing Unit: It comprises of the spault and tolling shaft. The spault is constructed from a pipe and cut to the required shape and the size.
It is done in a way to make complete assembly with the base when welded together. This unit homes time rotating shaft and permit growth rotation of the shaft.
The rotating shaft is of iron and machined to its size on the lathe machine.
The Grinding Unit: This consist of two grinding discs made of cast iron and highly tempered one of the disc is welded to the disc plate while the other is made movable and adjusted by the helk of an adjusting unit assembled on the collection unit.
Welding accessories
Electrode: It’s a metal rod having approximately the same composition as the metal to be welded.
Welding Shield: This is wan before welding and when removing flag from a weld.
Gloves: This protects the hand from ultraviolent rays and spathing hot metal.
Precaution to be taking when welding
i.    Never look at welding are without a shield
ii.    ii. Always turn off the machine when learning the work
iii.    iii. Always wear gloves and apron when welding
iv.    Use electrode holder that is completely insulted.
5.4 TESTING AND OBSERVATION
Before the machine is tested adequate measure must be taken to procedures-to be taken are as follow;
The machine grinder should not be operated with electric more than 8HP
I.   All moving parts must be properly lubricated
ii.   All bolts and nuts must be well tighten
iii. The machine must be placed in a non-slope floor to ensure stability
iv. The pulley of the machine (grinder) and the pulley of the electric motor must be property aligned.
OPERATION OBSERVATION
When the machine operate to grinding some quality of pepper and tomatoes it was observed that if is needed to regrind for about 3 times before the obtaining the finest nature. This was due to the sharpness of the grinding desk which eventually decreases as the operation of the machine continues.
As the vibration noticed during operation was eligible and the noise-making was very minimal and the various part of the machine remains efficient.