Metsä Board Simpele improves working conditions and safety with Valmet Fold-up Wall

The Valmet Fold-up Wall can be opened to the required height.

The Metsä Board Simpele mill in Finland is a leading producer of lightweight folding boxboard for various packaging applications, including food, medical, and frozen products. The mill employs 270 people and has an annual production capacity of 300,000 tonnes.

The hood of the BM 3 board machine required rebuilding when it reached the end of its lifetime. The mill selected Valmet as the supplier for the rebuild because of the Valmet Fold-up Wall, their innovative hood wall technology. The rebuild was carried out during the annual shutdown in 2023, and Valmet rebuilt the hood and installed a new Valmet Fold-up Wall in the dryer section. 

"The wall significantly aids in cooling the drying section, reducing the need for hot work and breaks."

The delivery covered everything from project management to installation supervision, to hands-on training. Dryer section ventilation, which is an important part of an energy-efficient drying process, was also improved by installing an additional pocket ventilation unit. 

Innovative hood wall technology

Four Fold-up Wall units were installed to replace the original lifting doors and fixed-wall elements on the tending side of the dryer section, creating 250 m2 of free access to the dryer section. The Fold-up Wall can be fitted to any manufacturer’s dryer section. Unlike in a traditional hood, the wall can be opened to any desired height during web breaks and fully during shutdowns, providing excellent access to the dryer section. Each element can also be opened individually. 

“We’re satisfied with the new Valmet Fold-up Wall. The fact that the entire wall opens up is an important advantage during disturbances. The hood cools down faster, and tasks like roll changes are easier to perform,” Metsä Board Simpele comments.  

Improved visibility enhances safety

The new wall enables the dryer section to cool down faster, as illustrated in Figure 1. The measurements performed at the Simpele mill showed that it took only 30 minutes to reach 52°C in the upper part of the dryer section when the wall was fully opened. Compared with the old conventional hood lifting doors, the same temperature level could be reached in 210 minutes. The Valmet Fold-up Wall therefore demonstrates a significant reduction in cooling time.

Figure 1. Measurements showed that the temperature dropped from 82°C to 52°C in just 30 minutes when the Fold-up Wall was fully opened.

The quick cooling enables maintenance work to be started shortly after a shutdown. It also lets staff work on the machine’s upper platform during shorter web breaks. The Fold-up Wall also improves visibility and lighting, facilitates roll and fabric changes, and improves the safety and working conditions of personnel. It is CE-marked and fulfills the requirements of paper machine standards EN 1034-16/EN ISO 13849-1.

“The Fold-up Wall improves safety by enhancing visibility across the machine area. The wall significantly aids in cooling the drying section, reducing the need for hot work and breaks. Usability is much better with the Fold-up Wall than with a traditional hood door,” Metsä Board Simpele says. 

“We’re very happy to support the mill in creating easier and safer working conditions during maintenance with the Valmet Fold-up Wall. We’ve been cooperating with Simpele for a long time and share their understanding that safety comes first,” says Simo Rahkonen, Senior Mill Sales Manager at Valmet.

Valmet contact person

Name: Simo Rahkonen

Title: Mill Manager Valmet

Tel +358 40 7048774

Email: simo.rahkonen@valmet.com

Text: Sofia Forslund and Salla Aalto