Optimized sawing process

Andritz Knife Systems, Iggesund/SE, dates back to the 17th century, when crude steel was produced under the name Iggesunds Bruk. Over the course of its 300-year history, the group gradually expanded its operations to include sawmills, chemical industries, and cardboard and paper production. In 1988, the company was split up, and the independent tool manufacturer Iggesund Tools was established. Since the acquisition by Graz-based technology group Andritz in 2011, the company has operated under the name Andritz Knife Systems.

50 years ago, the Swedish company launched a knife system for wood chip production on the market for the first time. At the time, the focus was on supplying high-quality raw material to the paper and pulp industry. In 1997, the company entered the sawmill sector with the development of chipping discs with reversible knife technology. Since then, Andritz Knife Systems has invested major sums in the development of the optimal design of the chipping discs.

For example, the TK-IV TurnKnife system, the latest generation, has three staggered reversible knives to guarantee an optimal cutting angle.

Suitable for all plants

The Andritz TurnKnife system is versatile: Existing chipper lines can be retrofitted with it, but it can also be installed in new plants. Andritz adapts the chipping discs to the respective local conditions regardless of the age of the plant or machine. “First, we analyze the condition of the machine, the types of wood processed, and the process parameters. Then, we optimize this production step for the customer,” Andritz product manager Andreas Henning explains.

The more reversible knives are mounted on the chipping disc, the higher the possible feed speed and the finer the resulting wood chips. With the exception of the circular saw blade and the dozer blade, the company manufactures all components in Iggesund. According to Andritz, the use of up to eight reversible knives per chipping disc offers significant advantages: high stability, quick knife changes, low maintenance costs, and consistently high wood chip quality. Thanks to the reversible function, each knife can be used four times.

Using wood chip quality to monitor the sawing process

In the early 2000s, Andritz developed the ScanChip Analyzer, a device for the precise optical monitoring of the quality of wood chips. The analyzer scans each chip individually and evaluates it based on country-specific norms or company standards. Originally designed for the paper industry, close monitoring of wood chip quality in a sawmill makes it easier to plan maintenance work on chipping disks and to optimize the intervals between knife changes.

Growing team

Andreas Henning, global product group manager of Andritz’s sawmill products, recently welcomed Per Herdegård to his team. Herdegård, who has 25 years of experience in mechanical engineering, will support service technician Jens Luthardt in supporting sawmill customers.