Large Pneumatic Cylinder with two input pressure

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Some manufacturing processes require use of large pneumatic cylinders. If the operation cycle of these cylinders are long, such as bonding of laminated materials, use of a single high pressure line is acceptable. However if the operation cycle is short, like an assemble operation, the use of a single air pressure for forward and retract stroke is not acceptable. This is because the air cylinder consumes ALMOST the same amount of pressurized air in retract stroke as the forward stroke. However the power need is confined to forward stroke, and the retract operation does not require significant power at all. To conserve the valuable pressurized air resources, it is advisable to use lower pressure air for retract operation as shown in this animation. Notice that to achieve this a high pressure air coming from pressure tank is divided into two line one of which is fed to the rod end of the air cylinder after passing through a pressure reducer. Also the connection of air lines to a five port four way valve arranged so that it allows two pressure line connection to one air cylinder as shown.