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Analysis1
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Braking System
Measurement

A.         Analysis of pneumatic operation:

Pneumatic is another mechanical driving method rather than electrical motor. It makes use of the mechanical properties of gases and the pressure difference to perform motions, such as linear and rotary motions.

 

Since Force = Pressure x Area, the pressure difference can generate a force. And Force = Mass x Acceleration, the force, therefore, can create a motion.

 

So, for many tasks, pneumatic can do it as well as electrical motor.

Method I:

Using a double acting cylinder as the main driver. Directly mounted the cylinder’s head on a metal arm and to the furnace as shown. So the cylinder extending will tile the furnace to pour the melt, while contracting the cylinder will restore the furnace position.

 

F = PA = Pπr2

Moment = FR > FL1

R = L1/cos50o

L2 ~ 2πR * 100o/360o

 

Moment 110Nm

P = 7bar

Flow Rate = 0.01m3/s

 

Cylinder I: Bore 12mm

F = 79.17N

L1 > 1.39m, R = 2.16m, L2 = 3.77m

 

Cylinder II: Bore 30mm

F = 494.8N

L1 > 0.22m, R = 0.345m, L2 = 0.602m

Advantages: Simple installation and easy operation.

Disadvantages: Since R > L1, the motion is as unsteady as the moment. The speed is too fast ~ 0.043 s/100o. The required stroke of the cylinder and the required metal arm length (R) are too long.

 

Method II:

Using a double acting cylinder as the main driver and a set of gear as the power transmission units. The head of the cylinder mounted to the rack which connect with a pinion. When the cylinder extend, it will drive the rack, the pinion and the spur gear and finally tilt the furnace. The backward motion is similar.

F = PA = Pπr2 = F1

F1R3=F2R2

F2=F1*R3/R2=F3

Torque = F3R1

L = 2πR3*R1/R2*100/360

 

Moment 110Nm

 

Cylinder I: Bore 12mm

F1 = 79.17N

F3 = 1363.8N

R3/R2 = 17.2

L = 300.2mm if R1 = 10mm

 

Cylinder II: Bore 30mm

F1 = 494.8N

R3/R2 = 2.76

L = 48.2mm if R1 = 10mm

Advantages: Simple installation and easy to operate.

Disadvantages: Since the R1 from the furnace is about 161mm, the required extension will be 0.78 to 4.83m. It may need a cylinder with very long stoke length. Although reduce the R1 could reduce the extension length, it will also reduce the allowance torque transmission.