An actuator is a motorized device that helps push, pull, twist, or apply an expected level of force. There are many actuators in operation all around you everyday. There are even actuators in power-lock car doors! That said, you may be wondering how long actuators last in terms of actuating action. To find that out, you have to delve into the world of actuators and understand what makes them work, and what makes them stop working.
Every actuator, whether it is an electrical, pneumatic, or hydraulic one, has an attached engine. The engine creates the force which pushes a piston or screw through a cylinder, thereby exerting force on whatever sits at the opposite end of the cylinder. In a continuous movement, the piston or screw is pushed forward and then quickly recoils or springs back in order to repeat the forward movement. None of this could be accomplished without the motor.
An actuator's motor can last several years if not used constantly. An example of an actuator that lasts a long time is the type of actuator found in power-lock car doors. It is only in motion when you hit a button to signal the actuator motor to move the piston or screw that acts upon the locking mechanism. This is why some car door locks can go ten or more years without needing repair to the actuators inside the doors.
On the flip side, you have actuators in industrial plants that are running non-stop. Even with the best of maintenance, and choosing electric valve actuators (versus hydraulic or pneumatic), the motors will give out after a few years. You can see why there is no direct answer in regards to how much actuating an actuator actually does before it needs repair when the motors have "x" amount of years in operation before they fail.
The Screw or Piston
The screw in electrical actuators does not need to be lubed as it just spins out one direction and then spins back again. It is powered by the electrical motor behind it. The screw's threads may wear out a little over time, but the screw in the electrical actuator still lasts much longer, does more work, and provides more precise force to the load in front of it than hydraulic and pneumatic actuators.
Hydraulic and pneumatic actuators rely on pistons to do the same work. They have to be heavily lubed and the piston chambers have to be smooth and easy. Small fires can break out if these actuators leak and are overworked, and pistons have been known to break and jam up the system. When you need these actuators to open valves, the last thing you want is a broken piston jamming up the works. If you only use these actuators on a semi-regular basis (and not continuously) you may get them to last as long as an electrical actuator that is run continuously for years.
The Ultimate Actual Answer on Actuating Lifespan of Actuators
So, obviously, the answer to how much actuating an actuator actually does depends on a number of factors. It depends on the type of actuator. It depends on how often the actuator is used and the frequency with which it is used daily. It also depends on whether you are using a piston or a screw inside the actuator's cylinder. All of these factors play a part in the durability and lifespan of an actuator. When you consider all of the above in regards to opening valves in an industrial setting, one type comes out on top. The durability and the sheer amount of torque that wins out comes from an electrical actuator.