Planing unit no. 5 has been in operation at Rettenmeier Holzindustrie in Ramstein, Germany since April. During the design phase, those responsible placed enormous importance on achieving a high level of flexibility, as Rettenmeier specialises in particular in supplying DIY stores.
The goal of Rettenmeier Holzindustrie is to increase added value in the company. “That’s why we invested in a further planing line in Ramstein”, explained Rettenmeier CEO Dr. Stephan Lang. He indicated that timber production in Ramstein is 600,000 solid cubic metres per annum in two shifts. The capacity of the planing units is about 200,000 m³ per annum. The sawmill group distributes around 35 % of the products it produces in the DIY sector. 35 % goes to the specialist German and international trade, 20 % to the industry and packaging sector and 10 % involves sawmill by-products.
Rettenmeier CEO Dr. Stephan Lang and Kallfass Managing Director Hans Haist (from l.) in front of the planing machine feeder.
Rapid output achievement
Those responsible primarily focused on flexibility and, simultaneously, a high level of availability with regard to the new planing line. For this reason, mechanisation was entrusted to Kallfass in Baiersbronn-Klosterreichenbach, Germany. “We knew Kallfass would supply the solution we wanted”, Lang emphasised. The mechanisation specialist had already converted an existing planing line in Ramstein, and this worked out perfectly. In retrospect, Lang is more than satisfied with handling of the project. “I’ve rarely experienced such a perfect commissioning. We achieved almost 100 % output after four weeks, and 6000 m³ of battens had already been bundled in this period. If we had to, we’d construct the plant in the same manner again”.
Kallfass adapted the new planing line to fit an existing facility exactly. The plant can process lengths ranging from 2 to 5 m, widths of 60 to 300 mm and thicknesses of 14 to 120 mm. Issues relating to available space mean the vacuum lifting device destacks the dried timber packages in layers. A stick stripper brushes the stacking strips down and conveyor systems collect these. An operator initially assesses the workpieces visually in the transverse transport. Following this, they are checked with a Brookhuis moisture measuring. “Unsuitable timbers can still be ejected here”, explained Kallfass Managing Director Hans Haist. Kallfass subsequently installed the longitudinal feed in the direction of the WJS planing machine. Depending on the timber length, this can achieve up to a maximum of 80 cycles a minute.
„Kallfass handled the entire project impeccably. We achieved almost 100 % output within four weeks.“
Dr. Stephan Lang, CEO of Rettenmeier Holzindustrie
Unsuitable dimensions can be stored temporarily onto a conveyor in film layers and then fed into the production process again.
Resorting for higher quality
There are two options downstream of the planing unit. Timbers that can be classified as a higher quality through cutting are sorted out to the left onto a conveyor in film layers. These can be fed into the process again if, for example, a dimension change occurs in the planing machine. “This resorting dispenses with the need for a further stacking system and complex trimmer station”, said Haist. The majority of planed workpieces are pulled onto a cross conveyor behind the conveyor with the temporarily stored film layers. An operator examines the workpieces here, ejects timber pieces of unsuitable quality and, by drawing on the timbers, can determine the chop cuts. In addition, Rettenmeier opted for a bundling system. In the case of single pieces, this simply involves “running over” these with transport chains. Kallfass also integrated a labelling system in this section. Kallfass was already involved in the development of this solution at Cordes, and it is also employed in Ramstein. “Both the bundles and wooden strips can be labelled”, explained Haist.
Following this, the timbers pass through the tried and trusted multiple cross-cut saw from Kallfass. The saw is equipped with four variable saw aggregates. The layers are then transferred to the stacking system which is equipped with magazines with automated stick placement. The stacker is also suitable for DIY packages (i.e. quarter packages). Finally, the finished packages are foil-wrapped and prepared for shipping. When it comes to foil wrapping, Kallfass provided yet another machine that mills the grooves in squared timbers. “This has proven its worth on numerous occasions”, said Haist.
“The new planing line allows us to achieve classic four-sided planing and, also, separation, or simply tongue and groove sections. That makes us extremely versatile. Kallfass provided us with a simple, but extremely efficient solution that allowed us to cover all requirements”, Lang confirmed.