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Actuators Precautions 1 Be sure to read this before handling. Design/Selection Warning 1. Confirm the specifications. Products represented in this catalog are designed only for use in compressed air systems (including vacuum). Do not operate at pressures or temperatures, etc., beyond the range of specifications, as this can cause damage or malfunction. (Refer to the specifications.) Please contact SMC when using a fluid other than compressed air made by pneumatic equipment (including vacuum). We do not guarantee against any damage if the product is used outside of the specification range. 2. Confirm the applicable specification range. The cylinder specifications listed in this catalog apply to standard strokes, including intermediate strokes. Please consult with SMC for specifications on long strokes. There are also some made-to-order products (-XBュ/-XCュ) for which product specifications do not apply. 3. There is a danger of sudden action by cylinders if sliding parts of machinery are twisted, etc., and changes in forces occur. In such cases, human injury may occur; e.g., by catching hands or feet in the machinery, or damage to the machinery itself may occur. Therefore, the machine should be designed to operate smoothly and to avoid such dangers. 4. If there is a chance that the product will pose a hazard to humans, install a protective cover. If the moving portion of the product will pose a hazard to humans or will damage machinery or equipment, provide a construction that prevents direct contact with those areas. 5. Be certain that the secured portions will not loosen. Be certain to adopt a reliable connecting method if the cylinder is used very frequently or if it is used in a location that is exposed to a large amount of vibration. 6. There may be cases in which a speed reduction circuit or a shock absorber is required. If the driven object moves at high speeds or is heavy, it will be unfeasible for only the cylinder’s cushion to absorb the shock. Therefore, provide a speed-reduction circuit to reduce the cylinder’s speed before the thrust is applied to the cushion, or an external shock absorber to dampen the shock. If these countermeasures are taken, make sure to take the rigidity of the mechanical equipment into consideration. 7. Consider the possibility of power source related malfunction that could occur. For the equipment that rely on power sources such as compressed air, electricity, or hydraulic pressure, adopt a countermeasure to prevent the equipment from causing a hazard to humans or damage to the equipment in the event of malfunction. 8.Design the circuitry 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. 9. Consider the behavior of the cylinder in the event of an emergency stop. Devise a safe system so that if a person engages the emergency stop, or if a safety device is tripped during a system malfunction such as a power outage, the movement of the cylinder will not cause a hazard to humans or damage the equipment. 10. Avoid synchronized operation using cylinders only. Even if multiple pneumatic cylinders are initially set to the same speed, their speed may vary due to changes in operating conditions. Therefore, avoid designs where a single load is moved by synchronizing multiple cylinder operations. 11. Consider the action of the cylinder when restarting after an emergency stop. Devise a safe design so that the restarting of the cylinder will not pose a hazard to humans or damage the equipment. Install manually controlled equipment for safety when the actuator has to be reset to the starting position. 12. Intermediate stops When intermediate stopped position is performed with a 3 position closed center type/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 in case it is necessary to hold a stopped position for an extended period. 13. Do not disassemble the product or make any modifications, including additional machining. It may cause human injury and/or an accident. 14. Refer to the Auto Switches Precautions for using with an auto switch. 15. When a cylinder is used in a clamping, suspending and lifting mechanism There is a danger of workpieces dropping if there is a decrease of thrust due to a drop in circuit pressure caused by a power outage, etc. Therefore, safety equipment should be installed to prevent damage to machinery and/or human injury. 8