Stora Enso and Valmet* (Metso (Paper) until Dec. 31, 2013) have entered an agreement about roll grinding for Stora Enso’s mills in central Sweden. The mills in Skoghall, Kvarnsveden, Fors and Skutskär are covered by the agreement. "There are already service agreements for rolls with Skoghall and Kvarnsveden, but now Fors and Skutskär are also included in a joint agreement," says Mikael Nyman, Service Manager, Scandinavia at Valmet.
"The expanded agreement is part of Stora Enso’s SMMS project (Six Mills Maintenance Sweden) that includes all of Stora Enso’s mills in Sweden and where the goal is to streamline further and coordinate maintenance at the mills," says Henning Ekström, Technical Manager at Stora Enso Kvarnsveden. "By working with joint purchasing, the conditions for closing favorable deals are better. Also, there is improved skills development as we benefit from the various experiences at the mills in the form of specialist functions and the best possible working methods. All this leads to reduced costs and increased reliability," Ekström explains.
There are a number of benefits with a tailored agreement. The continuous cooperation means that personnel at the service center become familiar with the different rolls out at the mills and the needs in terms of grinding and technical demands. All rolls are registered and documented at Valmet. A grinding data sheet is established which contains items such as grinding date, conducted grindings and information about any problems or previous damage to the roll. This information means that each specific grinding can be performed with the best possible final results. In the case of Kvarnsveden, Valmet enters the data directly in their maintenance system, thereby reducing administration significantly. Regular meetings are scheduled with agreement customers to discuss the servicing of the rolls and any problems that may have occurred during operation. In more complex cases, Valmet's accumulated expertise is at hand when it comes to rolls. The grinding need is discussed and planned to ensure that the workshops are used as efficiently as possible. This makes it easier for the mills to budget for roll maintenance, and easier for us to plan at the workshops when they know in advance when the grindings will be conducted, as well as the expected volumes for the year. However, it is up to the mills to decide when it is time to send the rolls for maintenance and regrinding.
Valmet's rolls service workshops in Borlänge and Karlstad, Sweden work in close cooperation according to a practical and flexible strategy. The cooperation between the workshops means that the capacity can be utilized maximally between the two centers. During vacation times and production peaks, when grinding needs are high, rolls can be moved or redirected to where there is capacity. Even the personnel resources are flexible and an exchange of personnel can be made between the different workshops so that personnel are available where they are needed most.
A regular exchange of skills, technology and methods is not only done among the service centers in Sweden. The cooperation also includes Valmet’s other units worldwide, but primarily those in Europe.
The very modern machinery in Borlänge and Karlstad consists of three Waldrich Siegen and Meuselwitz roll grinder machines. All grinder machines can handle a roll length of 15,000 mm and a roll diameter of 2,000 mm. The service workshops have a roll weight capacity of up to 120 tons. The measuring system has the latest technology, with 4-point measuring. The service center also performs 3D grinding. The service center schedule is full, but there is still capacity to grow by raising the level of utilization, e.g. with two or three shifts.
(*Metso (Paper) until Dec. 31, 2013)