In the event of a power or signal failure, the spring-return sets the valve to the “safe” position determined by the operator. The Mokveld axial flow valves require very low forces, since they are fully pressure balanced. This inherent design feature makes electric fail-safe control valves possible, even for large or high pressure valves.
Discreet open and close signals from a PLC or other system are most commonly used with open/close valves and can be used for modulating service as well. This is done with open/stop/close signals sent from pushbuttons or switches from the PLC or remote-control station to the actuator. Remote-control power can be provided on-site, or in some cases, actuators come equipped with a control power transformer that provides this voltage for the customer’s control system to use. For maximum versatility, our control valves and actuators come in different sizes, materials and connection options. They also offer a range of different functions and features to suit each specific application.
The duty cycle of a valve actuator has an impact on the service life of the actuator. Each actuator has an appropriate usage rate that guarantees the safe operation of the actuator under diverse operating conditions. The electric motor is likely to overheat, causing damage to electrode brushes and other actuation components. The Series 2000 electric valve actuator provides options in frame sizes, horsepower ratings, and output speeds.
Pneumatic actuators have an advantage in that it’s easier to control their speed. van điều khiển điện to implement speed control in a pneumatic actuator is to fit it with a needle valve, or a variable orifice, at the air pilot exhaust port. Electric actuators have geared motors and therefore it’s difficult to control the speed of these actuators without making gear adjustments. Pulsing circuits can be added in some cases to allow for slower operation. In addition to providing an electric 2-way control valve, COVNA also provides an electric 3-way control valve and electric temperature control valve for your choice. The upfront cost of a pneumatic actuator will typically be less than an electric actuator.
A compact range of linear pneumatic actuators that are a perfect match for Spirax Sarco’s line of globe control valves. An extensive range of sizes and spring ranges to suit valve shut-off requirements and process needs are available. We offer electric actuated ball valves manufactured with different materials to give you the best options in the market.