502
S. K. Sinha et al.
Table 1 Sprocket and chain parameters at each stage
Parameter
First stage vertical drive
Second stage horizontal drive
Chain link pitch
0.5 ~ 12.7 mm
0.5 ~ 12.7 mm
Sprocket
A
Teeth—25
Pitch diameter—101
C
Teeth—30
Pitch diameter
121 mm
B
Teeth—30
Pitch diameter 121 mm
D
Teeth—48
Pitch diameter
194 mm
Chain links
67
77
Chain length
851 mm
978 mm
Sprocket centers
251 mm
239 mm
Gear ratio
1.2:1
1.6:1
Chain speed
11.52 RPM
9.6 RPM
Output speed
9.6 RPM
8 RPM
First and foremost thing which should be kept in the mind is that this part is going
to face flame all the time and it is a moving part. Slat conveyor is one obvious choice
which is being widely used but again the budget constraint was there as the machine
should be economical. Then, we thought of having wire mesh conveyor which can
easily withstand flame, bake the roti while translating and get the job done.
We calculated the dimensions which came to be 250 mm wide × 4.125 feet long
and contacted an industry which can make customized belt to fit our need. But again,
we get to know that the required 37 mm diameter sprocket (with pitch 3/8 inch)
available in the market left us with only one material for our conveyor, i.e., mild
steel. Finally, we get our mild steel wire mesh conveyor.
3 Design Calculations
3.1 Stress Calculations for Square Pipe
Dimensions and properties of square pipes used in main frame structure are given as
follows (Fig. 8) [4]:
• Outer side length(c) = 25 mm
• Inner side length (d) = 22 mm
• Modulus of elasticity for mild steel (E) = 210 GPa
• Compressive strength = 50 MPa
• Tensile strength = 840 MPa.
Area moment of inertia (I) as stated by Bhandari [5] and by substituting the
dimensions given above, we get,
S. K. Sinha et al.
Table 1 Sprocket and chain parameters at each stage
Parameter
First stage vertical drive
Second stage horizontal drive
Chain link pitch
0.5 ~ 12.7 mm
0.5 ~ 12.7 mm
Sprocket
A
Teeth—25
Pitch diameter—101
C
Teeth—30
Pitch diameter
121 mm
B
Teeth—30
Pitch diameter 121 mm
D
Teeth—48
Pitch diameter
194 mm
Chain links
67
77
Chain length
851 mm
978 mm
Sprocket centers
251 mm
239 mm
Gear ratio
1.2:1
1.6:1
Chain speed
11.52 RPM
9.6 RPM
Output speed
9.6 RPM
8 RPM
First and foremost thing which should be kept in the mind is that this part is going
to face flame all the time and it is a moving part. Slat conveyor is one obvious choice
which is being widely used but again the budget constraint was there as the machine
should be economical. Then, we thought of having wire mesh conveyor which can
easily withstand flame, bake the roti while translating and get the job done.
We calculated the dimensions which came to be 250 mm wide × 4.125 feet long
and contacted an industry which can make customized belt to fit our need. But again,
we get to know that the required 37 mm diameter sprocket (with pitch 3/8 inch)
available in the market left us with only one material for our conveyor, i.e., mild
steel. Finally, we get our mild steel wire mesh conveyor.
3 Design Calculations
3.1 Stress Calculations for Square Pipe
Dimensions and properties of square pipes used in main frame structure are given as
follows (Fig. 8) [4]:
• Outer side length(c) = 25 mm
• Inner side length (d) = 22 mm
• Modulus of elasticity for mild steel (E) = 210 GPa
• Compressive strength = 50 MPa
• Tensile strength = 840 MPa.
Area moment of inertia (I) as stated by Bhandari [5] and by substituting the
dimensions given above, we get,