PNEUMATIC COMPONENTS
3.1 CYLINDER
Double acting air cylinders are always of piston type and are equipped with two inlets one on either side of the piston. Double action cylinders are capable of performing motions in both directions.
CYLINDER THRUST
The thrust (or) piston developed in the cylinder, is a function of the piston diameter, the operating air pressure are the frictions resistance. The thrust is measured in the static state and the frictional resistance corresponds to the breakaway moment of the piston. And in the static state, the frictional resistance is zero. Cylinder's thrust can be calculated by using the following formula.
Thrust = piston area multiplied by air pressure.
F = A * Pg.
FOR DOUBLE ACTION CYLINDER
Extending Stroke F = D2 * (3.14 / 4) * Pg.
Retracting Stroke F = ( D2 - d2 ) * (3.14 / 4 ) * Pg.
D - Piston Diameter ( cm ).
d - Piston Rod Diameter ( cm ).
A - Piston area ( cm2 ).
F - Thrust or Piston power ( Kgf ).
Pg - Operating air pressure gauge ( bars ).
AIR CONSUMPTION
The compressed air supplied to a pneumatic cylinder is consumed by the cylinder. The amount of air consumed is the energy, which is being converted into stroke in the cylinder. The consumed air is exhausted out to the atmosphere. Air consumption at a given operating pressure, given piston diameter and a given piston stroke is calculated as
Compression ratio piston area stroke
The compression ratio = 1.033 + operating pressure in bar/1.033.
FOR DOUBLE ACTING CYLINDER
Air consumption Q = 2 * ( s * n * q ) in 1/min.
Q - air consumption in 1/min.
q - air consumption per cm of piston stroke.
s - piston stroke in cm
n - number of operating cycles per minute.
The air consumption of the cylinder is stated in volume per minute. It is essential to know the number of operating cycles per unit of time.
One operating cycle is the movement performed by an activator from it's original position.
On a pneumatic cylinder one cycle is equal to two piston stroke ( forward stroke and return stroke ).
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Bore dia ( mm ) |
12 |
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Rod dia ( mm ) |
6 |
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Stroke |
25 / 100 / ( mm ). |
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Medium |
Compressed - Pressured - Lubricated Air |
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Temperature |
5 - 60 Celsius. |
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Materials of construction |
Aluminum, Brass, Nit rile. |
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Mountings |
Double foot Mouting. |
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Pressure |
0.5 - 10 bar. |
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WORKING PRESSURE IN BAR |
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Bore Dia ( mm ) |
Rod Dia ( mm ) |
|
2 |
3 |
4 |
5 |
6 |
7 |
8 |
9 |
10 |
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12 |
6 |
Extract |
20 |
30 |
40 |
50 |
60 |
70 |
80 |
90 |
100 |
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|
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Retract |
15 |
22 |
30 |
38 |
46 |
53 |
61 |
68 |
76 |