The Importance of Linear Actuators in Automated Machinery

Linear actuators are a critical component of industrial automation machinery and robotic systems. They provide the functionality and motion necessary for nearly every type of moving equipment, regardless of the type of actuation system or end-use application. Linear actuators provide efficient, accurate, precise and safe operations for manufacturing, testing, material handling, positioning, pressing, valve operation and many other applications–but which type of actuator is the best choice for your equipment?

Exploring Applications for Different Types of Linear Actuators

The Major Types of Linear Actuators

Linear actuators are available in several different types and technologies, but these are the most popular types found across multiple industries.

Pneumatic Actuators

Linear pneumatic actuators are often used for basic motion profiles and are typically found in industrial automation equipment performing simple tasks such as material transfer and handling, pick and place robotics, clamping, and indexing. These systems utilize compressed air to create mechanical movement and are known for being much simpler in their assembly and operation. They are generally used in low force applications and are a relatively inexpensive actuation alternative but are not as precise as electric actuation or as robust as hydraulic actuators.

Hydraulic Actuators

Linear hydraulic actuators, also known as hydraulic cylinders, are commonly found in heavy-duty applications that involve clamping, positioning, lifting and pressing. They take advantage of the high force density available with hydraulic power to provide mechanical operation and are known for being relatively fast, robust and powerful systems. However, hydraulic actuators are not as accurate as electric types without adding expensive servo valves and other components. In addition, hydraulic fluid leaks are inevitable and pose a safety risk to operators and the environment. Though robust, hydraulic actuators are inefficient, require regular maintenance and have far higher operating costs than other actuator types.

Electric Actuators

Linear electric actuators, often referred to as electro-mechanical actuators (EMAs) are typically found in automated machinery due to their precise and programmable movement. They are electrically powered and utilize mechanical components such as screws, gears and belts to actuate and transmit force. These actuators provide accurate position control, are programmable, energy efficient and offer relative flexibility in stroke length and speed of movement. However, EMAs are highly susceptible to damage from shock loads, and their mechanical components can wear prematurely over time due to metal-to-metal wear. Electric actuators are also relatively expensive, particularly in higher force configurations and require regular lubrication maintenance to prolong their life.

Combining Precision with Robust Operation: Kyntronics’ SMART Electro-Hydraulic Linear Actuators

Kyntronics developed a product range of electro-hydraulic actuators and servo power units that combine the shock load resistance, robustness and power of hydraulics technology with the precise control and energy efficiency of electro-mechanical actuators.

The actuator is a totally sealed, standalone design eliminating hoses and leak points which substantially reduce maintenance costs inherent with traditional hydraulic systems. In addition, the actuator technology is impervious to shock loads and metal-to-metal wear that damages and causes pre-mature failure of electro-mechanical actuators. The actuator uses power-on-demand to save energy and it incorporates closed-loop servo control of position, force and speed for precise process control, pass/fail determination and data collection.

Application Considerations for Linear Actuators in Automated Machinery

Linear actuators are used on many types of automated equipment. Typical applications include positioning, lifting, clamping, bending, pressing, forming, testing, material handling and many others.

Some key performance attributes to consider when choosing the type of actuator for your machine design include:

• Load profile: how much force is required to move the load and is the load required to be held in a static position.
• Speed is required to achieve the desired cycle time.
• Level of precision control required for position, force, speed, and combinations of these.
• Level of robustness; is there risk of shock loading, side loading, or concentrated loading (load at the same position of the actuator stroke) during operation that could cause failure and unplanned downtime.
• How much regular maintenance is required, and risk assessment for unplanned downtime maintenance.
• Environmental and Ergonomic factors such as energy usage, fluid replenishment and disposal, noise and safety risk.
• Digital Transformation: does the actuation system provide data for analysis, predictive maintenance and IoT connectivity.
• Cost; both upfront one-time costs and ongoing operating costs. Operating costs are often many times higher over the life of the equipment than the upfront cost depending on the actuation technology chosen.

Kyntronics all-electric SMART linear actuators address these performance requirements and much more. Contact Us to find out how and learn more about this innovative actuator technology.