The recently completed upgrade to the Northern Waste Water Treatment Works in EThekwini, involved both electrical and mechanical changes to the existing system. One of the suppliers selected to support this project was Aumanat. The company, a leading actuator specialist, is based in Mahogany Ridge, just outside of Pinetown and was established in 1995 by its owner, Peter Meyer.
According to Ashley Pillay, the design engineer on the project, Aumanat was chosen for the project based on previous experience and for their unsurpassed record in after sales service and communication protocol.
The product supplied for the project was the latest generation .2 AUMA actuator as well as the necessary controls. The purpose of an actuator is to open and close valves. They can be used for isolation or for control and have been installed on penstocks, sluice gates, gate valves and buttery valves throughout the plant from the head of works all the way through the digesters, primary setting tanks and clarifiers.
The actuators are controlled via Modbus Interface and the generation .2 actuators feature non-intrusive settings.
The AC controls are ideal when the application requires self-adapting control functions, data logging, configurable user interface or if valves and actuators are to be implemented into a Plant Asset Management by advanced diagnostic function.
AC controls are equipped with large and freely programmable parallel interfaces to established fieldbus systems with process automation, including the Profibus DP-V2. For fieldbus connections, AC programming can be performed from the control room.
The diagnostic functions comprise a time-stamped event report, torque characteristics logging, continuous recording of temperatures and vibration within the actuator and also counts the number of starts and motor running times.
The AC01.2 also offers a number of special functions, including torque by-pass to unseat valves if tightly seated and functions for modifying operating times to avoid water hammer within pipelines. The AC 01.2 design is user friendly and integrates actuators easily into the DCS.
Aumanat has been successful in securing the upgrade for the Kwamashu Waste Water Treatment works from the same client, and installations have already commenced on site. According to Peter Meyer, “AUMA are the world leaders in the field of electric actuators and our success is the result of both a high quality product and our commitment to uncompromising service”