SMC Networks RS2H Series, Operation Manual

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Warning
(1) Design the circuit to prevent sudden lurching of driven objects.
When a cylinder is driven by an exhaust center type directional control valve or when starting up
after residual pressure is exhausted from the circuit, etc., the piston and its driven object will lurch
at high speed if pressure is applied to one side of the cylinder because of the absence of air
pressure inside the cylinder. Therefore, select equipment and design circuits to prevent sudden
lurching, because there is a danger of human injury and/or damage to equipment when this occurs.
(2) Intermediate stops
When an intermediate stopped position is performed with a 3 position closed center type or double
check valve type directional control valve, it is difficult to achieve accurate and precise stopped
positions due to the compressibility of air.
Furthermore, since valves or cylinders are not guaranteed for zero air leakage, it may not be
possible to hold a stopped position for an extended period of time. Please contact SMC if it is
necessary to hold a stopped position for an extended period.
Caution
(1) Use a speed controller to adjust the cylinder drive speed, gradually increasing from a low
speed to the desired speed setting.
6. Maintenance
6-1. Check items
The following checks are required for proper cylinder operation.
1) Smoothness of performance
2) Change of piston speed and cycle time
3) Abnormality of stroke
4) Looseness of cylinder mounting bolt and any other bolts
5) Looseness of the cylinder mounting frame and abnormal deflection
6) External / Internal leakage (output change)
7) Damage to piston rod sliding parts
8) Oil leakage of shock absorber, abnormal impact sound, vibration or external appearance.
9) Looseness of bolt in the locking mechanism, or abnormality of parts.
10) Air filter drainage
11) Lubrication of piston rod and rotating sections (e.g. Lever pin, Roller pin)
12) Auto switch position
Check all the above. If there is any problem, examine the cause and take necessary actions such
as further screw tightening and grease application. Contact SMC when the cylinder needs
to be repaired.
Warning
(1) Perform maintenance inspection according to the procedures indicated in the
operation manual.
If handled improperly, malfunction and damage of machinery or equipment may occur.
(2) Maintenance work
If handled improperly, compressed air can be dangerous. Assembly, handling, repair and parts
replacement of pneumatic systems should be performed by trained and experienced
personnel.