Part of the story began in March, 2008 when Cartiere Modesto Cardella commissioned Andritz Pulp & Paper to supply a two-layer headbox with dilution control, a profiler, and the gap former. But, according to Mario Cardella, chairman of the mill's board and Modesto's father, the story actually began in 1977, the year PM 4 was built.
"In the mid-1990's, the basic PM 4 machine was no longer able to deliver the formation and profile the market required for top-quality paper," Mario says. "So, in 1995 we renovated the machine, which also set the stage for future investments." Today, PM 4 has a design speed of 1,200 m/min and a wire width of 3.18 m. Containerboard with a 90-170 g/m2basis weight range is produced from 100% recycled fiber.
"It is not our style," says Modesto, "to routinely make changes to our equipment, but rather to focus on projects that will last for years to come. That is why we made the investment in the gap former."
Mario Cardella, chairman of the mill’s board
A question of lightness
The strategy behind the investment is to enable the Lucca papermaker to meet the demands of a newer European market trend - basis weights below 100 g/m². "The gap former is a big step that permits PM 4 to manufacture paper in a style unusual for us," Modesto says. "On our smaller PM3 machine, we will continue to produce a product consistent with the standard requirements of the Italian market. This way, we are ready to supply virtually any type of demand."
Once the strategy and goals were set internally, the analysis began to decide which machine manufacturer to approach. The choice was Andritz. "For us it was an opportunity, because it permitted us to establish a special relationship with the supplier," Modesto explains. "We knew that it would be their first installation. We knew this project would get their focused attention and utmost commitment. We already knew of their expertise and product quality, and these things also swayed our decision. But, it was not merely a technical choice."
Since this was the first installation of a gap former for packaging grades by Andritz, comprehensive pilot trials were performed during the proving of the roll-shoe forming technology - the PrimeForm TW.
First results after start-up confirmed a successful transformation from pilot plant to mill production line. Paper quality was significantly improved, and runnability has been excellent.
Christoph Draxler, Andritz startup engineer
Made to measure
This project was developed by the paper mill and the supplier together. "Andritz's technology adapted perfectly to our requirements," Modesto says. "The machine had to fit into an existing space that was rather low and tight. There were also constraints due to the controls that had to be taken into account." The gap former was therefore tailor-made on the basis of these requirements.
"The positive aspect is that we now have access points on the line that we did not have before," Modesto continues. "The main water runoff channels are leaning against the cantilever and therefore move together with the machine." This solution came from Andritz's gap former for tissue machine, but has shown itself to be extremely useful for the Lucca paper mill as well. "It was not easy to overcome these challenges, but with the team of well-trained engineers, there were no real difficulties. "It was just laborious, that's all."
Start up and go!
According to Modesto, results were forthcoming from Day One. "We were able to produce paper right away. It was 28 January 2010. We had some initial problems with the presses, but a few hours later, after adjusting one things, we were able to start production. From then on, everything went smoothly."
"For our part," says Christoph Draxler, the Andritz start-up engineer, "we can say that a positive environment was established, from the start, with the management down to the machine operators. "It was a little surprising how quickly the machine achieved stable running condition. We planned for various potential problem scenarios ahead of time, but didn't have to implement any of these plans."
The gap former parameters are currently being optimized on PM 4, but already the machine is producing a 100 g/m² sheet at speeds above 800 m/min and is being ramped up toward its maximum design speed of 1,200 m/min. "Very definitely over and above our expectations," Modesto reports. "We are very satisfied."
"Little by little, we are discovering the characteristics of the machine," says Andrea Moretti, manager of the San Pietro a Vico mill. "One month after start-up we are performing paper tests in cooperation with Andritz. We are intent on discovering all the nuances that the gap former is contributing to our production process. And, Andritz also want to evaluate certain machine settings. Thus far, we have seen that when we are running under consistent machine, speed, and output conditions, we achieving the very best mechanical paper properties. Before the gap former, there were considerable variations. Still, it is a bit too early to talk about performance levels."
Andritz’s PrimeForm gap former
More to explore
The PrimeForm TW is smoothing production of the entire line because there are less parameters to be kept under critical control. Mario Cardella explains: "The whole line is more stable in that it is less sensitive to fluctuations of whatever enters the machine. With the formation being produced by centrifugal force - and centripetal force in the first section - the machine is less affected by variations in the furnish or by operator actions. Even though we have not yet assessed all the improvements the gap former will enable us to achieve, we know, for example, that there has been no increase in power consumption. This development is very promising, but we will only be able to talk about real energy savings once we have maximized the use of all the various instruments."
The Lucca installation has turned out to be a great training experience for the supplier as well. "There has been an exchange of information helpful to both parties," Modesto says. "We were very demanding, often forwarding detailed requests, and Andritz backed us up all the way. They could have chosen to supply the machinery and leave it at that, but they were anxious to understand our requirements and offer ways to improve the installation. For our part, we contributed all the details relating to paper management, production, and maintenance, and their engineers translated all this information into a useful product."
Austrian Italian mix
The human aspect of such installations can never be taken for granted. "Working with their engineers was stimulating, even though initially we did not fully understand each other perfectly," Modesto says. "We very much appreciated the determination which distinguishes the Austrian character, because results proved the validity of their approach. Over all, we managed to blend together our Mediterranean temperament and their Central European character."
"Working with Andritz was a positive experience from all points of view," says Moretti. "We were pleased with the technical training received by our personnel."
What would Cartiere Modesto Cardella do differently if it could turn the clock back? "Nothing," concludes Modesto Cardella. "We are more than satisfied with our experience and are very pleased to have had the chance to work on this project together."
Paper for corrugating
|Cartiere Modesto Cardella was the brainchild of four Italian brothers -- Francesco, Modesto, Pasquale, and Giovan Bernardo. In 1946, they opened the mill at San Pietro a Vico (Lucca). In 1953, Modesto became the sole owner and began implementing an investment strategy which continues to distinguish the firm.
In 1966, after Modesto died, his son Mario took over, carrying on his father’s work and continuing to reinvest profits. In 1977, the new PM 4 was installed. In 1995, both production lines were revamped.
Today, Mario is chairman of the board and has been joined by his children Modesto, Rosaria, and Cristiana, all of whom are board members.
The mill produces paper for corrugating machines, with a total potential capacity of 170,000 tonnes/yr. PM 3 has a working width from 2.5 to 2.55 m and the width of the newer PM 4 is 2.65 to 2.8 m. About 80% of sales stays in Italy, while the remainder goes primarily to the Mediterranean Basin.