One of Schubert & Salzer’s goals in developing an AS interface was to make installation fast, reliable and easy while keeping connection costs low. This innovative bus system at the actuator-sensor level has proved highly popular, especially in drinks sector technology. An AS-i-based system makes it very easy to install, start up and reliably monitor modular-built plants in particular. Schubert & Salzer has therefore incorporated AS-i networking technology into its new 8049 digital positioner to exploit the key benefits of AS-i into their actuating and control valves, namely:
• Reduction in cabling cost and effort.
• Significantly fewer sources of faults.
• Simpler installation and commissioning.
The digital AS-i positioner for actuating pneumatic control valves is linked to the master by means of the characteristic yellow, twin-conductor AS-i cable, whose dual function is to supply power while simultaneously transmitting data.
By developing the 8049 AS-i positioner in a so-called “top-mounted” configuration in which it rests centrally over the valve actuator and does not have to be linked via an actuating lever on the side, this design provides very high hygiene standards and is ideally suited for integration into food and drink process technology. For reasons of operating reliability and hygiene, on-site operation has been reduced to a minimum and is limited to self-balancing and to adjustment of the positioner setting locally. This is all that is required since the 8049 digital positioner can be configured very easily for the tasks in question via the AS-i connection, a PC interface and a user-friendly GUI. Furthermore, AS-i permits the use of remote diagnostic tools to interrogate the status of the equipment at the control valve and to access any error messages. Diagnosis through the Internet is possible also, and the AS-i structures can be seamlessly embedded in other bus structures through appropriate gateways.
The benefits of the AS-i positioner can be combined with different actuating and control valves to provide individual modular process solutions. Examples of this can be found in the processing technologies in the brewing and drinks industries, where the 6020 hygienic control valves, the 6021 aseptic control valves and the sliding gate valves can be used with the digital AS interface positioning system.
The 6020 hygienic control valve is a self-draining right angled valve and is made from solid, non-porous stainless steel. Precision turning, polishing, fine polishing or electro polishing are used to achieve the surface quality required by the particular process. The 6021 aseptic control valve has a completely smooth diaphragm to provide a complete separation between the processing region and the piston rod. Both the 6020 as well as the 6021 valve ranges are offered in the nominal sizes DN 15, 25 and 40 up to a PN 16 pressure level. Sliding gate valves are precision devices used for liquid, vapourphase and gaseous media in many adjacent areas in brewing and drinks process engineering. Sizes in this case range from DN 15 to DN 200 for pressures up to PN 100 and media temperatures from -60 to 350°C.
For more information contact Rowan Blomquist, Macsteel Fluid Control, +27 (0)11 383 4000, [email protected], www.macsteel.co.za
© Technews Publishing (Pty) Ltd | All Rights Reserved
printer friendly version