Consistent quality with QCS upgrade
A new scanner, multi-variable controls and a very successful steam profiler installation ensure top reel quality for Port Townsend Paper. Production increases of over 10% on a benchmark grade add to the investment return.
Port Townsend Paper Corporation is located on the shores of Puget Sound in Washington State, United States.
PM 2’s quality and profile control capability had not been updated since the early to mid-1990s.
To maintain a competitive edge and meet today’s more exacting quality control standards, improvements had to be made.
|Solution||Quality control upgrades in several steps: The older slice control equipment was upgraded with new electronic controllers with faster and more precise control capabilities, a new higher resolution Valmet IQ QCS system replaced the old Valmet unit, and new multi-variable MD and CD controls and closed-loop automatic grade change controls were implemented. The final addition was a new IQ Steam Profiler moisture profiler which replaced an older steam shower.|
The multi-variable CD control has resulted in a “dramatic improvement” in CD moisture profiles as attested by Dave Harke, Paper Mill Production Manager.
Over a two-month period, 2-sigma variability averaged below 0.5% and that is a significant improvement from before-control figures. The precise control by the steam profiler has allowed the mill to turn off the water spray moisture profiling system, thereby saving the energy required to remove the extra water.
Altogether, the improved control and extra dryness from the press has made a major difference in machine productivity as well as quality. Tim Reandeau, machine tender, estimates that the production rates of the benchmark 23-lb medium grade have been increased from 38 to 42 tonnes per hour – slightly better than 10%.
|Keywords||Automation, Improvements, Rebuilds and upgrades, North America|