High-precision Auma solution for multiport valves

Auma offers a new high precision automation solution for multiport valves based on SAVEx electric actuators with adjustable motor speed. The actuators support up to 16 ports with a combination of short operating times and excellent precision, thanks to their variable speed motors. Positioning accuracy is better than 0.3°, making the actuators suitable for the most challenging applications in this market. Multiport valves with lift plug design are also supported.

Multiport valves find application in the oil and gas industry in sampling systems for multiple wellheads. Fluids from each well in turn can be directed to a single sampling system, allowing operators to monitor current production in detail. The positioning accuracy required makes this a challenging application for actuators.

Auma’s SAVEx variable-speed actuators are ideal for this task. For rapid switching, the actuator motor runs at high speed over most of its travel. Just before the valve plug reaches the target port position, however, the speed is considerably reduced. By virtually eliminating overrun, this allows extremely precise positioning.

Auma therefore supplied two SQ 07.2 part-turn actuators with AC 01.2 actuator controls and two FQM 07.1 fail safe units for the cooling system valves. The FQM fail safe units use mechanical energy, in the form of a constant-force spring motor, to open or close valves when electric power is not available.

In high-pressure and high-temperature environments multiport valves often feature a lift plug design. This makes actuation even more demanding since two different movements have to be coordinated: before the plug can rotate to the desired port it has to be lifted from its seat. This requires a second actuator. Auma’s clever and simple solution is to use two actuators in a master-slave configuration that appears to the DCS as a single actuator. The intelligent actuator controls handle the complete sequence of movements and the safety interlock.

Auma has also expanded its list of communication protocols supporting multiport valve functionality: Foundation Fieldbus is now also available, in addition to Profibus DP, Modbus RTU and Modbus TCP/IP.