Process control throughout a vast array of industries relies heavily on the humble solenoid valve and its ability to perform both reliably and efficiently
Michael Hannig, Global Product Manager for Solenoid Valves at Bürkert Fluid Control Systems, looks at the improvements in design that have allowed an increasing number of processes to rely on this essential device.
Solenoid design now and into the future
Over 90 percent of all solenoid valves are equipped with single coils, the simplest of all coil types, which uses an enamelled copper wire wound on a coil bobbin. Bürkert coils are designed for continuous operation and are always coated with an insulating mass to ensure high electrical and mechanical protection. For applications involving ambient temperatures up to 250 °C, anodised enamelled aluminium wires are used to ensure reliable operation.
Development of the basic design principles has led to reduced energy consumption with the introduction of the double coil design. This uses two independent windings with high and low power. The high power coil opens the valve and then integrated electronics switch over to the low power coil to provide the holding force.
As many industries look to reduce the footprint of a variety of control processes, so there is a need to develop smaller control devices that still provide the necessary power and energy savings. Bürkert has addressed this requirement with the introduction of the TwinPower solenoid which uses two parallel windings on the coil yoke. The integrated electronics switch the coils from parallel to series connection, which reduces the holding power to 25 percent of that required for opening the valve.
The design of the coil and its operation has a direct effect on the performance of the valve. The latest energy saving designs allow the coil to be overexcited to open the valve and within half a second, the current is reduced by 95 percent, which is still sufficient to hold the valve in the open position. The cumulative effect of this type of feature can have a significant impact on the energy required for process control. Increased reaction speed, energy saving and reduced size are all themes that are expected to continue to influence valve design into the future, as are more specialised applications…
Se il processo di produzione comprende prodotti alimentari liquidi, le plastiche ed elastomeri utilizzati dovrebbero essere conformi alle norme alimentari e igieniche locali. Inoltre, alcuni processi richiedono un ciclo di pulizia da eseguire tra processi produttivi e quindi è richiesto anche i dati per questa procedura anche per garantire che non vi è alcuna degradazione del materiale indesiderati causati dal vapore o pulizia chimici.
Some applications involve potentially explosive atmospheres and therefore any equipment operating in this environment must have been certified to the appropriate ATEX directives. Similarly, components for other specialised applications such as cryogenic systems, must be designed to not only withstand the extreme temperature but continue to operate reliably.
Complete control over production delivers quality and peace of mind
Manufacturers such as Bürkert not only design a comprehensive range of solenoid valves to cover both standard and specialist applications, but also manufacture every component which includes the machining of the valve body, the winding of the coil and the injection moulding of the coil encapsulation. In this way, Bürkert has control over every aspect of the valve and can therefore guarantee performance.
The testing of individual components and complete valves is a continuous process, partly to ensure continued compliance with a wide range of certification, but also to ensure that the high quality standards are being maintained. In this way the customer can be sure of reliable operation, even in harsh operating conditions.
On the face of it, selecting a solenoid valve appears to be a simple enough decision, however, making the right choice requires an in-depth knowledge of the process under control as well as expertise in the materials and designs available. By combining the knowledge of the process engineer with the fluid control experience of a manufacturer, customers can be assured of a high quality product that will deliver long-term reliability while also complying with the appropriate industry standards.
Con oltre 60 anni di esperienza nella progettazione di valvole a solenoide, Bürkert continua a migliorare la tecnologia e i materiali utilizzati nella loro costruzione. L'esperienza nella progettazione e nella specifica dei componenti per i sistemi di controllo dei fluidi è disponibile per ogni cliente, garantendo che sia il componente che l'applicazione funzioneranno come previsto.
Bürkert Fluid Control Systems
Centro Fluid Control, 1 Bridge End, Cirencester, Gloucestershire, GL7 1QY, Regno Unito
Sistemi di Burkert Fluid Control
Fabbricazione di apparecchiature di processo. Uno dei pochi produttori a fornire soluzioni per il ciclo di controllo completo.