Cowan Dynamics
This article has been reviewed by Cowan Dynamics Application Engineering team. Contact Us and our application engineers will assist you with your application.
Electro-hydraulic actuators are devices that operate a valve through pressurized hydraulic fluid, however, their main source of energy is solely electrical. The electrical power supplied is used to energise a motor that runs a hydraulic pump which then supplies the pressurized fluid to operate a hydraulic actuator which controls the valve.
The complete system is self-contained, eliminating the need for a separate hydraulic power unit, simplifying system construction and improving safety and reliability.
A self-contained electrohydraulic actuator can be used with linear or rotary valves, the need for its use will depend on the requirements of the application. These devices are ideal for operating valves that need large torques or thrusts, or where fail-safe systems or high operating speeds are required.
Electro-hydraulic VS Hydraulic Actuators
Electro-hydraulic actuators differ from traditional hydraulic actuators primarily in their power source and system design. While both use hydraulic fluid to generate motion, electro-hydraulic actuators are powered entirely by electricity, whereas hydraulic actuators rely on an external hydraulic power unit (HPU) to supply pressurized fluid.
In a hydraulic actuator system, a separate hydraulic power unit is required, consisting of pumps, reservoirs, and valves to generate the necessary pressure. These systems are commonly found in large-scale industrial applications where centralized hydraulic power is available.
In contrast, an electro-hydraulic actuator integrates a hydraulic pump, fluid reservoir, and actuator into a single self-contained unit. This design eliminates the need for an external HPU, simplifying installation, reducing system complexity, and improving safety and reliability by minimizing leak points.
Electro-hydraulic actuators are particularly beneficial for applications that require high force, rapid actuation, and fail-safe operation without access to an external hydraulic infrastructure. They are often preferred in remote locations or where maintenance access is limited, such as offshore oil rigs, mining equipment, and power generation facilities.
What We Offer
Cowan Dynamics offers a line of electrohydraulic linear actuators, which are compact, self-contained devices that have a thrust capacity of up to 282,600 in-lbs’ plus an on/off and modulating service. It also has a line of electrohydraulic rotary actuators, E2HR, which have a torque capacity of up to 300,000 in-lbs’, as well as an on/off and modulating service.
Both lines of actuators provide safe valve closure, speeds of up to 20 degrees per second for rotary or 1 second per inch for linear and very low power consumption.
