Proven center-roll based press section for lighter grades
OptiPress Center – center roll based press section - is a reliable, well-known concept that combines close to 40 years of pressing technology experience with modern shoe press technology. With this solution, a shoe press replaces a roll just before the first open draw. The resulting boost in dryness thus fully benefits web runnability in the open draw. If necessary to meet end quality requirements, a center-roll based press can be followed by a separate roll press.
In the containerboard production from recycled fiber, machines dedicated to high speeds and light basis weights can be equipped with an OptiPress Center pressing process.
Picture: OptiPress Center center-roll based press section.
Innovation: Closed sheet transfer with OptiPress Center
Transfer belt technology allows the draw between the press and dryer sections to be closed in center roll-based concepts, too. Less draw is required, and dryness and end product qualities, such as strength and porosity, improve. Rather than a transfer belt, it is also possible to use a smooth, heated metal belt that goes around the center roll and guide stretcher roll, This metal belt technology further improves press section performance, as the increased temperature of the paper web enhances dewatering in the press nip.
Notable track record
There are hundreds of outstanding Valmet OptiPress Center (formerly named as SymPress) press sections operating successfully around the world in paper and containerboard production machines – for new lines and rebuilds alike.
OptiPress Center press section benefits
- Compact design and easy to apply also in rebuilds
- High dryness and good moisture profiles
- A reliable, well-known concept with numerous references in both board and paper machines
- Added capacity potential in rebuilds
Customer success stories
New press section rejuvenates Greif corrugating medium machine
A new OptiPress press section, with matching Valmet clothing included, boosts productivity, improves quality of the corrugating medium and reduces energy consumption at Greif Packaging mill in Riverville, USA.
Superior quality paper after rebuild - Sappi Gratkorn PM 11
Sappi's Gratkorn mill rebuilt their PM11 to improve the printing paper quality. The rebuild concept was optimized for improved formation and printability and reduced two-sidedness and validated in the series of pilot trials at Valmet facilities.
More efficiency and runnability with new OptiPress
When the press section of Mondi’s Štêtí's PM5 was rebuilt, the mill had sellable sack kraft paper in just three days. With increased dryness resulting in better web runnability and less steam consumption, the mill is happy with the OptiPress concept and co-operation with Valmet
Capacity increase rebuild in Mexico
Mexican Pondercel selected Valmet to modernize their PM 1 papermaking line at the company’s Anahuac mill in order to increase capacity. The rebuilt production line has significantly increased speed and production capacity
From paper to packaging - StoraEnso Varkaus PM3
In 2015, Stora Enso converted their existing paper machine In Varkaus Mill to produce linerboard to better meet the market need for renewable packaging. PM 3 is almost like a new machine now; a combination of brand new and good, well maintained trusted technology.
OptiConcept M board making line at Pratt Industries in the USA
Pratt's new containerboard production line, PM 16, successfully came on stream in 2015. This is Valmet's first OptiConcept M installation in North America.