Fabrication Of Yam Pounding Machine

The specific static load rating in capacity Co
Co    =     Specific static load rating or capacity = 10KN
Ko    =    Factor depending on the type of bearing   = 12.3
Dw     =    Diameter of the ball
a    =    Normal angle of contact = 0
i    =    Number of rows of ball in any one bearing = 1
z    =    Number of balls per row in the groove = 6
Ko    =    QMax
        DW2
Qmax = Maximum bearing load
And from the above, the ball diameter can be calculated

Qmax =     Ko x DW2
    =    12.3 x 26.032
    =    8333.33N
A bearing of 6206, which is of an inner diameter of 30mm and outer diameter of 62mm, then was chosen. The bearing number interpreted as 200 means a light bearing of bore that is inner diameter of 06 x 5 = 30mm.
Also, in the selection of this bearing, the radical load of which the bearing can carry was considered. However, for the ball lubrication, grease should be used at low and medium speed when the temperature is not over 20oC while oil should be used at higher speed.
Hence, in this design, grease is the most satisfactory lubricant
3.3.2    BELT SELECTION
The first key decision before installation is to choose the correct belt type for this machine. The belt type is an important aspect to take into account, as it allows major cost savings. Belts may be used as a source of motion, to transmit power efficiently, or to track relative movement. There are different types of belts:
•    Flat belts: Used to transfer power from engine flywheel. They are also used in countless farming, mining and logging applications; such as sawmills
•    Round belt: They are circular cross section belt designed to run in a pulley with a 60degree V-groove. Round grooves are only suitable for idler pulleys that guide the belt, or when O-ring type belts are used.
•    V-belt: It solves the slippage and alignment problem. It is now the basic belt for power transmission. They provide the best combination of traction, speed of movement, load of the bearings and long service life. The general cross-section shape is trapezoidal (hence the name “V”) optimal speed range is 1000-7000ft/min (300-2,130m/min), V-belts need larger pulleys for their thicker cross-section than flat belts.
For the purpose of this design, V-belt is selected for the transfer of power.