Components that require little energy to ensure economic and energy-efficient plant operation are becoming more and more important. In automated valves, solenoid valves convert electric control signals into pneumatic control signals. Apart from reliable operation, power consumption is a decisive factor when selecting components.
Two different Samsomatic solenoid valve technologies exist.
On the one hand, there are solenoid valves with air consumption: the solenoid valves with the flapper/nozzle assembly, which has proven reliable in service a million times over (see cpp 1/2014), have the advantage that the solenoid valve body and actuator spring chamber are effectively protected against corrosion by constant purging with air. This unique selling proposition makes it possible to use these valves outdoors in damp or corrosive ambient conditions.
On the other hand, there are solenoid valves without air consumption: these valves, which feature an armature, allow energy-efficient use indoors. For example, cost savings in the compressed air supply can be achieved in batch processes in the pharmaceutical industry. Samsomatic has extended its product range to meet demands for energy-efficient devices.
Safe with low energy consumption
The newly developed Type 3969 solenoid valve with intrinsic safety is approved for explosive atmospheres (gas and dust). In accordance with the temperature class, it can be used at ambient temperatures from -45 to +80 °C. Certification for use in safety-instrumented systems (SIL according to IEC 61508) has been applied for.
The rugged, corrosion-resistant aluminium enclosure provides protection in severe ambient conditions (IP 65 according to IEC 60529).
The Type 3969 solenoid valve consists of an electropneumatic binary converter with an armature and a booster valve with a switching diaphragm and return spring. The electro-pneumatic binary converter is designed for DC voltage signals from 14 to 28 V and can be operated using suitable valve driver cards. Thanks to its low power consumption, it can be actuated by means of intrinsically safe fieldbus signals.
The supply air is routed internally when the solenoid valve is used in combination with actuators for on/off service. When the solenoid valves are mounted on actuators for throttling service or on a positioner, external supply air is used. The air supply can be changed over simply by turning a gasket.
The installed pressure reducer maintains the supply air pressure under 1.9 bar.
In the idle position, the armature is pressed against the seat of the supply air port by a spring. When the solenoid coil is energised by a DC voltage signal, a magnetic field is created. As a result, the armature is lifted out of the seat against the force of the spring and drawn into the exhaust air port. The switching diaphragm in the booster valve is actuated and the supply air port is connected to the output port (KVS 0.3). As soon as the solenoid valve is de-energised again, the armature is pressed against the seat of the supply air port and the switching diaphragm is switched over to the idle position by a return spring.
Universal attachment
The Type 3969 solenoid valve can be mounted on rotary actuators with a Namur interface (VDI/VDE 3845), on linear actuators with Namur ribs (IEC 60534-6) or on pipelines using customised mounting kits. Various actuator transit times can be set by installing an additional restrictor plate for exhaust or supply air.
Thanks to their modular design, Samsomatic solenoid valves can easily be replaced with a differently configured model to adapt them to changed requirements. For example, installed solenoid valves can be upgraded by exchanging them for solenoid valves without air consumption. The lower energy consumption and the resulting cost savings ensure economical and energy-efficient plant operation in the long term.
www.cpp-net.com search: cpp0117samsomatic
Gerald Fiedler
Public Relations,Samsomatic
Share:
