What type of actuator is the right one for your project?

Of course, this question cannot be answered offhand and frequently, several types of actuators are possible and it is up to the customer to make the final decision.

Before a specific type of actuator can be determined, a number of questions will have to be answered, such as “What must / should the valve be able to do?”, “How often will the valve have to be operated?”, “Which level of failure safety will have to be achieved?” Additionally, it is important to know what installations are already available on site, how stable the power supply is at the place of installation and how much space is available to the fitters. There are, however, some factors which clearly show the advantages and disadvantages and have a considerable influence on the customer’s decision.

The advantages of an electric actuator include e.g. that it can be very accurately mounted and that a battery powered emergency power supply can be installed to provide energy in the event of a power outage. Emergency closing via the manually operated handwheel or the hand lever as well are an option in case the power supply system fails.

The VAG EKN® Butterfly Valve with VAG HYsec Hydraulic Brake and Lift Unit is an interesting valve for which hydraulic power plays a vital role. Due to its great power generation capacity, the HYsec is an essential component of the valve as very quick closing of the valve has to be ensured to prevent serious consequential damage. This is mainly the case when the valve unit is used as quick-closing valve in turbine inlets and pump stations, as pipe-burst safety device with electric tripping or as quick-opening valve in a turbine bypass line.

The pneumatic actuator is the most cost-effective of the actuators mentioned here. The biggest advantage the pneumatic actuator has to offer is the fact that it can still be operated in the event of a power outage until its air tank is empty. Because air as the source of energy can be highly compressed, it can be stored relatively easily in tanks which can be refilled when empty. The medium of compressed air can be very easily processed and generated.