AN APPROACH TO ENERGY CONSERVATION IN PNEUMATIC SYSTEMS WITH METER OUT CIRCUIT

Air cylinders have been used with meter out control. In these cases, the outlet pressure of air compressors are set at 0.5~0.7[MPa] for consumption air saving, and so downstream pressure of the actuator is low level, such as nearly atmospheric pressure. For pneumatic energy conservation, it is most important that supplying air use effectively. A lot of small cylinders are worked in automatic factory product systems, and air supply lines are longer between compressor and these cylinders. So, in a plant, energy consumption of pneumatic system is bigger and gets big losses. In this paper, the authors propose that the exhaust pressure of the cylinder hold middle level (0.2~0.5[MPa]), and so the downstream available for running air blow guns etc. This paper shows the air cylinder dynamics at start and stop, then the parameter are exhaust pressures, cylinder load, supply piping length. Assuming that exhaust flow is used effectively, the proposal method available to prove energy conservation of pneumatic systems. For example, the exhaust pressure setting 0.2[MPa] reduce 15% of pneumatic energy consumption.