22 loop PID for Refiner, consistency, level and Sequence control
45 loop PID, 3 Stepping for basis weight valve and sequence control
17 loop steam control and speed control with tele DC Drive (By MODBUS)
Factory Managers Nightmare
Many factory owners and managers wake up in the night from their worst nightmare: Their factory control equipment has grown old, unreliable with expensive or unavailable spare parts, maintenance cost and shutdown time are increasing steadily. Then they would have no choice than to shut-down the their mill for weeks or months and wait until all control systems are replaced and re-tested.
Well, we have good news for them: NOT ANY MORE. Process control systems can be replaced without process disruption and without additional shutdown.
Hard to believe? Now the readers of this are probably mostly engineers, so they are not in favor of fairytales but want to see hard proof. And there is hard proof. It's about the size of a soccer pitch and up to 12 m meters high.
A paper machine, located in Prachinburi, about 2 hours east of Bangkok. It is really a "green field mill", around it only rice fields as far as the eye reaches.
The control system for pulping, stock preparation and approach flow had been completely replaced with B&R 2005 + Wizcon SCADA, replacement of controls for the paper machine and drive system is still in progress.
Paper is a continuous process, online 24/7; so the objectives for the control system replacement were:
to work only during the monthly 1 day service shutdown
to replace the old system in stages, so old and new system would have to cooperate in the early stages
to be able to switch back to the old control system in 1 hour in case of unpredictable trouble (however we never had to make use of it)
to upgrade loop functionalities to full control from the SCADA
The project is a full success with no major glitches.
So in case you are a factory owner or manager and you wake up in the night from your worst nightmare then come to visit this paper mill east of Bangkok. Listen to the owner's happy story, have a look over the rice fields and find again peace of mind …