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Neues Schwachholzsägewerk EN
An Absolute Jewel:
New Thinnings Sawmill

GELO Timber decided to pick a sorter with 40 inclined boxes. The boxes are around 30 % larger and therefore suitable for dimensions with a width of up to 1.65 m and a height of 2 m.

Smart, clean and safe

Kickoff in Wunsiedel was December 2019, with the first trunk being fed through the new line exactly one year later. Construction of the GELO Timber sawmill continued during the most difficult times imaginable. Despite all the adversities the Corona pandemic presented, it proved possible to adhere to an already tight schedule.

The main product, predominantly DBH lamellas, is intended for the supply of laminated wood plants. Side boards which cannot be processed are supplied to packaging customers. “The sawmill will reduce purchasing considerably for both companies in future. However, 100 % self-sufficiency is not possible”, explains Küspert. Wunsiedel primarily proved attractive as a location because GELO Timber had in WUN Bioenergie a pellet producer and cogeneration plant operator as a neighbour. But WUN Bioenergie is not just any neighbour: Küspert is co-initiator of the energy park and, additionally, a shareholder and Managing Director. This creates attractive synergies with, in essence, sawmill waste being exchanged for electricity and heat. Küspert calls the sawmill the “Smart solution 4.0”.

An enormous feat

Construction commenced in Wunsiedel in December 2019. An already tight schedule was adhered to, despite the Corona pandemic, and the first trunk was fed through the saw line a year later in December 2020. “It was an enormous challenge for everyone involved, but we were able to commission the plant within the given time”, says the Managing Director, and he is proud of how successful this cooperation has been. A second shift was already launched a few weeks ago. The sawmill has been designed for an annual output of 350,000 solid cubic metres in two shifts. “That may not seem a lot at first glance, but more than 18 million linear metres of logs need to pass through the plant every year to achieve this output. Our sawmill in Weißenstadt, where we process larger diameters, is only handling 4 million linear metres for an output of 250,000 m³/per annum”, relates Küspert. The Wunsiedel sawmill is intended for thin-end diameters of 8 to 25 cm and a timber length of 2.5 to 5.3 m.

Excellent cooperation: Wolf-Christian Küspert (l.) with Kallfass Project Manager Matthias Link.

Clean sorting and packetising

Main and side boards from the HewSaw line are conveyed in two decks to the sorting and stacking system from Kallfass in Baiersbronn-Klosterreichenbach/DE. The mechanisation specialist also installed an automated stick feeder. The main and side boards are fed through a separator onto a curved conveyor. The worker assesses the timbers on the downstream conveyor. If a face section is necessary, he pulls the board up to 0.5 m from the conveyor. During the visit, Kallfass Project Manager Matthias Link pointed out the rollers that make handling of even heavy boards extremely easy.

Single feeding with a TongLoader towards the scanner and trimmer occurs in the transverse run-through. The TongLoader grips each piece in a manner similar to a hand, separates the board film, singulating and feeding it into the next conveyor. The significant advantage of the TongLoader is that it can also handle different timber dimensions, piece by piece. Link indicates that the Kallfass sorting system output is up to 120 cycles per minute.

A Microtec scanner determines the dimension and detects the wane. The Variosort sorting control system assigns each board an appropriate box number and information for the downstream Kallfass trimmer. The latter has seven saw blades and can also be used for destructive cuts. “The operator can also indicate additional characteristics for boards through colour marking, indicating conditions such as beetle damage, blue stain or rot”, explains Link.

“This is an absolute jewel, and we’re proud to have commissioned the plant on schedule, especially in such a challenging time”.

Wolf-Christian Küspert, Managing Director GELO Timber

Boxes up to 30 % larger

GELO Timber decided to pick 40 inclined boxes. In order to reduce stacking on the premises, the Kallfass system can stack packages with a width of up to 1.65 m and a height of 2 m. These dimensions also facilitate best possible exploitation of the Valutec continuous kiln. Kallfass created larger inclined boxes than usual for this reason. “The boxes are around 30 % larger”, says the Kallfass Project Manager.

Full boxes are emptied downwards onto a cross conveyor and separated by a step separator. Kallfass also installed the re-sorting system for kiln packages above the cross conveyor, with one kiln package making up to two or three shipping packages. These are separated in layers through tilt destacking. The stacking sticks fall automatically onto a conveyor belt and are collected separately.

A worker can even assess the quality of both fresh and kiln timber again if necessary, or reject undesired pieces. Subsequent to this, the Kallfass mechanisation system creates the layers according to the package specification, and these are conveyed through the Kallfass multiple cross-cut saw. This is equipped with a zero line and four variable chop saws. Placement forks then transfer the completed layers to the packet assembly system. Stacking output is up to twelve layers per minute.

The Kallfass packet assembly system is equipped with eight double magazines for kiln and dispatch sticks. Kiln sticks are 1.6 m long, while dispatch sticks have a length of 1.2 m. Strip laying is automatic. Finished packages are lowered using a paternoster lift. Fresh material is conveyed from there to the Valutec continuous kiln opposite. Shipping packages are conveyed to a Fromm strapping station which Kallfass has retrofitted with an automated feeding system for squared timbers.

As initially mentioned, Kallfass also provided the automated stick feeder for kiln and dispatch sticks. The feeder was automated to cope with the volume of kiln sticks required. Stick bundles are transferred to a cross conveyor and separated. A scanner checks the dimensions and detects damage to sticks such as knotholes and splitting. Unsuitable sticks can be ejected downwards through a flap. Following scanning, a fixture collects the sticks, bundling ten sticks together in each case. Dispatch sticks are provided using a manually charged pouch conveyor. A robot grips the stick packages, filling the stacker magazines with them. The major advantage of this solution is the option to position the magazines variably and still fill them automatically.

 

Successful project

Complete administration of the sawmill is handled by GELO in Weißenstadt. This enabled them to keep personnel figures low in Wunsiedel. “We currently have 32 personnel working in two shifts. The sawmill can be operated by a mere eleven people during each shift. We wanted to build an absolute jewel – and we’ve succeeded in this in every respect. All the solutions involved were implemented exactly as we imagined. The new sawmill means we are well equipped to face the future”, says Küspert. He is particularly proud of the overall concept involving the neighbouring pellet and cogeneration plant – “It’s a location advantage that nobody can take away from you”.

The complete investment involved EUR 38.5 million. The sawmill location covers an area of 11 ha, 7 of which are presently in use. Küspert also has a few pleasant ideas regarding the rest of the location. “But first, our main focus will be on the new sawmill”, concluded the Managing Director.

The main and side board assortments are fed to the Kallfass sorting and stacking system via two buffer decks and a curved conveyor.

The worker pulls the boards forwards for the end section, with rollers facilitating the work.

The TongLoader ensures a rapid cycle feed towards the scanner and inclined boxes.

The multiple cross-cut saw from Kallfass trims the layers with a zero line and four variable saws.

GELO Timber employs a stick robot from Kallfass to facilitate filling of the double magazine.

One of the first completed timber packages from GELO Timber in Wunsiedel – cleanly cut, stacked and dried and destined for laminated wood production.

Images and text: Martina Nöstler, Holzkurier 11/2021