Choosing the right electric linear actuator is an essential part of any successful automation project. There are many actuator models – parallel, L-shaped, or inline motor –used in a wide range of applications. Each project need is unique. To help you select the right actuator, consider the application and its technical constraints: speed, load, duty cycle, available space, environment, and more.
1. Define the Required Load
The load to be supported is a determining factor in the actuator choice and will define its various components (motor, nut, spindle, gears, ball bearings, etc.).
It is crucial to define which direction the actuator will operate (pull, push, vertical or horizontal movement) and over which length. It will also depend on the diameter of the actuator’s inner and outer tubes. All these factors influence the actuator’s ability to lift loads and have an impact on its strength.
2. Define the Required Speed
The desired speed is a fundamental parameter in the selection of the actuator.
Not all mechanisms or materials are compatible with high speeds. High speed with a high load can cause premature wear of the actuator and affect its lifetime. Therefore, each device has speed and load that must not be exceeded to protect it from material damage. This speed depends, among other things, on the pitch and the motor characteristics.
3. Define the Duty Cycle
The duty cycle defines the ratio between the on-time and off-time of a device and varies considerably from one application to another. The duty cycle is essential to determine the actuator, its materials, and its mechanisms. It helps give the equipment an optimal lifetime and limit mechanical parts’ wear or possible overheating.
Electric actuators with parallel motors, for example, with their spur gears, will withstand a higher duty cycle and have a higher number of cycles.
4. Define the Available Space
The system’s available space also informs the choice of the actuator.
In addition to load, stroke, and speed, it is necessary to consider whether the actuator will have to operate in a restricted space and if there are any space restrictions to allow integration into the application.
For example, inline electric actuators, due to the motor’s alignment with the spindle, are more compact, making them ideal for tight installation spaces. An actuator’s mounting dimensions depend on the mounting configuration (inline, L-shaped, or parallel motor).
5. Define the Environment
The environment in which the equipment will operate is a crucial parameter to choose the right electric actuator.
Questions to consider: Does the equipment operate indoors or outdoors? Is it exposed to dust, solid contaminants, or moisture? Does it have to withstand intensive cleaning with detergents or high-pressure cleaning? Depending on the environmental requirements, the materials used and the ingress protection (IP) rating will differ. Does it require a silent operation? For example, L-shaped electric actuators, with their plastic worm gears, provide a quieter movement, ideal for medical or domestic equipment.
Everything Is Variable; Everything Is Adaptable
The choice of an electric actuator depends on many parameters. It is important to choose a linear actuator that meets the application requirements. Every application includes a list of requirements that must be met to choose the right electric actuator. Budget is also a factor in project planning. Some unavoidable technical constraints will require a larger budget. The important thing is to evaluate all these parameters to create the most suitable device.
We hope this has helped you develop a better understanding and foundation for electric linear actuators and their incorporation into linear motion systems. Next, we will review the critical components inside and outside of an electric linear actuator. If you have further questions and/or would like help with your next application, please contact our global team. We specialize in partnering with our clients while providing quality solutions for their actuation needs. JDR would be glad to assist you.
