Wet pressing is a vital part of paper and board processing and benefits both runnability and quality. The ultimate target of wet pressing is to increase sheet dryness to ensure paper and board machine drying capacity and also to enable web runnability at the beginning of the dryer section. The press section also has a great effect on sheet surface properties. Valmet’s OptiPress Linear, double-nip press with linear web run, is an ideal solution to fulfill papermakers’ requirements for effective pressing.
The operating performance of OptiPress Linear press section has proven that the design principles employed – no open draws, shoe press technology, and full-width tail threading – provide excellent end-product quality, high-level dewatering capacity as well as good runnability. This results in a press section where press-related runnability bottlenecks, such as open draws, are a thing of the past.
The closed web run significantly reduces web breaks and thus improves runnability. OptiPress Linear press section also provides very good paper and board quality with symmetrical sheet properties, good moisture profiles, excellent dry content, and high production efficiency.
A press section with two shoe nips provides superior quality properties at the desired bulk level. As a rule of thumb, the first shoe press nip controls the bulk, and the second press nip controls the dryness and bulk.
OptiPress Linear features SymBelt shoe press technology, which provides longer dwell times and higher press impulses that improve dryness after the press section. A high web dry content brings savings also in drying energy. The two straight press nips of OptiPress Linear produce a strong web and ensure good moisture profile in the web after the press section.
OptiPress Linear for containerboard grades.
Arkhangelsk Mill aims for competitive advantages after the rebuild of BM2. "We have a wide basis weight and end product format range for flexibility. We expect decreased costs and energy consumption: 15-20% heat savings, 8% electricity savings and 5% reduction in water consumption," says Alexander Tuvanof.
“There is an increasing demand for packaging board in India and board has an important role in replacing plastics. We needed a trustworthy equipment supplier and technology which can convert raw material to a high-quality board in a cost-efficient way", says Sanjay Singh, CEO of ITC Paperboards and Specialty Papers Division.
Asia Symbol Paper's two Valmet paper machines, PM11 and PM12 set a reference quality level for the global and Asian markets. Xinhui PM12 is equipped with the latest technology like shoe and blade forming technology to create a competitive edge for Asia Symbol in the future.
In big grade conversion rebuilds, customers always want to be on the safe side as far as risks are concerned. Because the designed forming section was first of its kind, the prototype was tested at the Paper Technology Center in Jyväskylä. With the promising results of the pilot tests, Blue Paper was willing to implement the rebuild with Valmet.