Oman Flour Mills Co. goes for WinCos07/14/2009 The existing silo facility of Oman Flour Mills Co. (S.A.O.G.) in Ruwi/Port Qaboos in Oman was built by Bühler in the seventies and has a total storage capacity of 130,000 metric tons. The plant stores and handles 400,000 tons of material a year, predominantly wheat and other grains. In 1995 Bühler updated the electric control system and replaced the relay-based system by a PLC-based one with graphic process visualization. The customer is convinced of the quality as well as the top service offered by Bühler. Thus, 14 years later, Bühler was once again awarded a contract in 2009 for updating the existing plant control system. It incorporates the state-of-the-art programmable logic control (PLC) system S7-400 of Siemens and the newest-generation Bühler process automation system WinCos.
The bulk storage silo is controlled through six independent process lines. The heart is the ship unloading system capable of conveying 500 metric tons of grain per hour, which is accurately weighed and binned. The 96 storage bins can be accessed via 15 different process paths. Smart algorithms allow optimal path selection and the flexibility required to intervene in operations whenever the need should arise. The entire silo is controlled from two stations, which enable or disable access to the individual functions on the basis of detailed allocation of user authorizations.
Detailed and accurate data
The existing weighing system determines the actual data and transmits them to the WinCos process automation system, where they are processed into job reports, bin contents calculations and job statistics.