Schnittholz in Pufferspeicher, cut wood in buffer levels

Optimales Kurzholzhandling EN Optimum short log handling

Tailored solution for an exceptional sawmill

With log lengths of 1.1 m and over, the Lithuanian Juodeliai Group recently commissioned a high-performance sawmill for producing raw material for pallets. Machine suppliers were also faced with major challenges, given the short logs involved and a planned output of 250,000 m³ of sawn timber per annum. Extensive experience and the level of commitment on the part of suppliers such as Kallfass ensured the success of the project.

The latest and, simultaneously, largest sawmill in the Juodeliai Group is currently operating in Marijampole/LT. The largest sawmill group in the country encompasses four locations and is responsible for cutting over 1.3 million solid cubic metres of logs per annum. Juodeliai aims to produce around 650,000 m³ of pallet timber in 2022, generating over € 200 million in turnover as a result. With customers in over 40 countries, the company is highly export oriented, although, according to CEO Andrius Zimnickas, no business relations are cultivated with Russia or Belarus, despite their geographic proximity. The company mainly obtains its spruce and pine logs and, also, hardwoods from Lithuania, a fact that also makes Juodeliai the largest consumer of timber in the country.

The company commissioned a fourth sawmill in 2020 in Marijampole, about a two-hour drive west of the capital Vilnius. Designed for an annual capacity of 250,000 m³, Juodeliai also produces pallet timber there for the global market. When it came to machine suppliers, the company opted for proven plant solutions from companies such as Linck, Holtec, Microtec and Kallfass. The latter is responsible for the mechanisation, sorting and stacking of main products and side boards.

„A practical, solution-oriented approach is the main reason we are cooperating again with Kallfass.“

Andrius Zimnickas, Juodeliai Group CEO

A challenging project

Kallfass takes charge of the main product upstream of the two multi-blade saws. A vertical system transports the separated logs as a whole to a peel-off system. Aided by gravity, these form a veritable carpet of boards. After passing a visual inspection station, layers are formed and the boards are cut at both ends before being fed layer by layer to a stacker.

Kallfass Abblätterer, peel-off system

Separated logs are transported to the Kallfass peel-off system to create layers of boards.

Adequate capacity

Kallfass collects the side boards in buffer levels. “As we had little experience with these short dimensions, the design was partially based on assumptions that, ultimately, worked out very well indeed”, reported Kallfass Project Manager Matthias Link.

Solution-oriented approach

This was neither the first nor the last joint project for Kallfass and Juodeliai. The German plant engineers had already been involved in a greenfield project for the Lithuanian timber industry in 2014. “We’re delighted to have opted again for Kallfass. They never try to offer us prefabricated solutions, but rather concentrate on our ideas and implement these. This practical approach is the main reason we decided to work with Kallfass again”, emphasised Andrius Zimnickas, adding that the next project, a second main product stacking system for Marijampole, has already been commissioned. This will be commissioned in the 1st quarter of 2024 at the latest.

Holz Imprägnierung, impregnation of wood

Application of an impregnation agent

Kallfass Abblätterer, peel-off system

Separated logs are transported to the Kallfass peel-off system to create layers of boards.

Sortierförderer, sorting conveyor

Kallfass sorting conveyor for ejecting unsuitable products.

Pufferetagen mit Seitenware, buffer levels with side products

Side view of the products buffered in 4 levels.

Versandpaket mit Kufen und Umreifung, shipping package with strapping and supporting runners

The completed shipping package, with triple strapping and supporting runners.

Images: Kallfass, text: Günther Jauk, Holzkurier

Holzkurier 17/2022

Emptying sorting box

Sortierwerk kann trocken und nass EN Sorting system for wet and dry

Sorting and stacking of dry timber and fresh wood in a single plant. Mostovdrev in Belarus has invested around EUR 2.5 million in an automated Kallfass sorting system.

Mostovdrev is a joint stock company and one of the largest wood processing enterprises in the Republic of Belarus. In addition to being sold in Belarus, its furniture, construction and finishing products are also exported to the CIS countries, Europe and the Middle East. Mostovdrev is firmly committed to strict quality control and use of the latest production technology. For this reason, the company decided to expand its sawmill through the addition of a new combination timber sorting system with connected stacking plant from Kallfass. Installation was completed last year, followed by commissioning of the plant. Mostovdrev’s declared production target is to process 100,000 m³ per annum.

Vertical Box Sorter

Kallfass timber sorting system with 20 vertical boxes and a box for non-assignable pieces

Transparent processes in the sorting system

Both dry timber and fresh wood from spruce and pine are processed at the Mosty location in two shifts. The main product and side boards are received from the EWD saw line and fed to different buffer conveyors for unscrambling. Alternatively, the dried or damp product can also be fed to the unscrambler via a tilt destacking system. A package chain conveyor upstream of the tilt destacking system buffers up to 3 packages (with sizes of 1.5 x 1.5 and 1.2 x 1.2 m). The separated timber is backed up and cycled onto an assessment chain conveyor for manual quality control. Each board is individually accommodated and rotated for inspection on both sides before being deposited again on the conveyor. A worker examines the product and can realise chop cuts by pulling waney timbers a little from the conveyor. Product dimensions are subsequently checked and classified before forwarding to the sorting system. Mostovdrev has chosen a compact sorting system with 20 vertical boxes and a box for non-assignable pieces that can be filled with timber lengths of 2,000 to 6,200 mm at a rate of 60 cycles/min. Sorting programs and Kallfass visualisation software facilitate management and enhance the transparency of processes in the sorting system. Fault messages and board data can be archived and recorded.

Stick placement with magazines

Stick magazines for automated placement of dry sticks on stacking layers

Stacking with automated stick placement

In order to stack the sorted timber, the first 5 sorting system boxes are first emptied contrary to the conveying direction onto a conveyor and, only then, conveyed further in the conveying direction to avoid tilting of timbers. The batch then needs to be unscrambled before layers can be created with widths between 1,200 mm for shipping packages and 1,500 mm for drying packages. The downstream Kallfass multiple cross-cut saw is equipped with 4 freely adjustable saw units and cuts the trimmed product precisely in layers to desired lengths (shortest crosscut length 1,200 mm). Stored cutting programs facilitate quick batch changes where necessary.

Individual layers can be stacked in the stacker in single or multiple layers of packages with a maximum width of 1,500 mm. Placement forks then pick up the individual cut layers and place them on the package to be formed. Placement of drying sticks between each layer is automated and realised at a defined distance with 12 stick magazines. Dispatch sticks are laid manually. Finally, the completed packages with a maximum length of 6,000 mm are marked with a label and strapped to increase stability.

Assessment chain conveyor_measurement

Classification of timber prior to sorting through quality assessment with an assessment chain conveyor (rear) and dimension measurement system (front)

Feeding box sorter

Charging of vertical box sorting system at 60 cycles/min.

Emptying sorting box

Emptying of boxes onto a discharge conveyor, with the first 5 boxes contrary to the conveying direction to avoid tilting

Unscrambling_Separating

Unscrambling of batches following emptying for subsequent formation of layers

Multiple cross-cut saw

The Kallfass multiple cross-cut saw cuts timber in layers to desired lengths

Stick placement with magazines

Stick magazines for automated placement of dry sticks on stacking layers

Hobellinie Van Roje, planing line, ligne de rabotage

Flexibles Hobeln kleiner Chargen bis 8 m Länge EN Flexible planing of small batches up to 8 m in length

Holzwerke van Roje installs a new planing mill in its existing facility at the Oberhonnefeld-Gierend location (Rhineland-Palatinate).

Holzwerke van Roje strengthened its own finishing with the installation of an automated planing mill last year. Connected to the sawmill, around 50% of the main product is processed further here. The company invested around 3.7 million euro for this purpose in the new plants.

Satisfied with the cooperation and results of the project (from left): Planing Mill Manager Eduard Dück, the Managing Director of Holzwerke van Roje, Gerhard Hauschulte and Kallfass Director Hans Haist.

Holzwerke van Roje GmbH & Co. KG operates a sawmill at its Oberhonnefeld-Gierend location (Rhineland-Palatinate) with an annual timber output of around 450,000 solid cubic metres. 90 % spruce and 10 % Douglas fir are currently processed, but Managing Director Gerhard Hauschulte estimates that pine will be added to this again to ensure the availability of timber logs in future. A planing mill and pellet production facility producing 80 000 t per annum are attached to the saw mill, and a cross-laminated timber production facility is currently under construction. Holzwerke van Roje currently has a workforce numbering 160 employees.

The planing mill was completed last year as a completely new installation at the plant and adapted to meet the special needs of sawmill production. The objective is to clearly strengthen processing of sawn timber. Up to 70,000 m³ of planed workpieces will be produced per annum from the main product, which is equivalent to about 50 % of the main product produced in the sawmill.

Kallfass GmbH in Baiersbronn delivered the complete fully automated mechanisation technology for the new Rex “Big Master” planing machine from Georg Schwarzbeck GmbH & Co KG in Pinneberg, including a wrapping station. A cupping and moisture meter, a “Golden Eye” quality scanner from Microtec, a marking station from REA JET and the strapping unit from Fromm are integrated in this facility.

Hobeleinzug, Planer Infeed, chargement de raboteuses

Kallfass planing machine feeder

Einzug REX Big Master Hobelmaschine

Infeed side of the REX “Big Master” planing machine

During conversion planning in April 2020, the two existing planing lines were dismantled in June of last year. Kallfass began at this time to install parts of the mechanisation technology in cleared areas of the facility while production was still underway. Commissioning of the complete plant then followed at the beginning of September. The plant was producing around 400 m³ of planed workpieces a day in 2 shifts by the end of the year.

Production at the van Roje sawmill is very customer-oriented, serving buyers all over Europe. There is a focus on markets in the Netherlands and United Kingdom with the majority of orders for lengths exceeding 6 m. Van Roje has also concentrated on the European market in recent years, exploiting domestic sales opportunities freed through the booming US sawn timber market. Stock dimensions up to 620 mm and log lengths of 3 to 14 m are cut. The maximum length in the timber sorting system is 8 m. Frequent product changes of up to four times an hour are part of everyday production at van Roje. This means that, when it comes to the cross section and length, a broad variety of dimensions is encountered in the planing mill, and it is necessary to work with relatively small batches. The smallest batches frequently involve only two packages per dimension. The planing mill therefore needs to be very flexible and produce everything from roofing battens with numerous special dimensions to raw solid structural timber. The maximum dimensions of completely planed products at van Roje are 150 x 320 mm. In particular, the maximum possible length of up to 8 m means the plant differs from the majority of industrial planing mills.

Minimum adjustment times and “profile management” on the planing machine

The flexibility required at van Roje is reflected in the configuration of the Rex “Big Master” planing machine: With ten planing cutterheads (four horizontal and two vertical tools and four individual chamfering tools for an all-round workpiece chamfer) finished product widths of 60 to 400 mm and heights of 15 to 200 mm can be created with continuously adjustable feeds of 30 to 150 m/min. In addition to planing and profiling, single and multiple cutting to length of the workpiece is also possible, and van Roje uses up to five saws.

Different board widths can be processed in layers simultaneously on the machine with only narrow gaps between them. Width adjustment is servo controlled at an adjusting speed of 20 mm/s. The Rex profile management control system enables storing of working shaft positions which have been configured. If a particular profile needs to be repeated, the operator, after deploying the required tools, can select the profile using the assigned workpiece name. The machine then automatically moves each spindle into the correct position. Shafts not required for a procedure go into idle mode, leading to a palpable reduction in the electric power input.

Hobelline, Planing line, ligne de rabotage

Schematic depiction of the van Roje planing mill. The material moves from charging and tilt destacking via a sorting conveyor to the Kallfass planing machine feeder. A triple cross-cut saw is installed upstream. A Microtec quality scanner (1) is installed behind the Rex planing machine. Options then available are a bundling station (2) and marking station (3), after which the product is transferred to the wrapping and strapping station (6) by one of the two stackers (4 and 5). The packages are output to the right onto the acceptance point in front of the plant (7). Ejection of material from the sorting conveyor is possible (8).

Compact mechanisation for workpiece lengths up to 8 m

Kallfass installed a fully automated mechanisation solution here with an interface connection to the van Roje ERP system (Timbertec). With regard to operation of the planing mill, aside from the plant operator and a stand-in, only two other employees are required for wrapping.

Following tilt destacking of the raw material packages (presorted in the sawmill in the case of freshly cut material) and separating, unsuitable material can still be ejected from the sorting conveyor prior to planing machine charging. The plant can therefore also be used for stacking of drying packages. A growth ring detector (cupping detector) integrated on the unscrambler and a moisture meter from Microtec combined with a board turner contribute to the improvement of planing quality. Timber that is too moist can be ejected and raw material turned, depending on the growth ring position.

A freely positionable triple cross-cut saw is installed upstream of the planing feeder and frequently used at van Roje. Cutting upstream of the planing machine achieves absolutely fringe-free cuttings. The feeding of the planing machine achieves 50 cycles/min. Directly downstream of the planing machine, the workpieces pass through a “Golden Eye” scanner from Microtec that organises the product into strength classes C16 and C24. They can then be separated from each other in the passage and either sent directly to one of the two stackers or, previously, to a bundling unit. Adaptation of CE certification for mechanical sorting is currently underway at van Roje. The customer can therefore be offered a combination of mechanically and visually sorted planed workpieces.

Four strapping stations are available at the bundling unit. Up to ten stick bundles can be created there every minute. Packages can be produced on stackers equipped with stick magazines at a rate of 10 layers/min.

Flexibility and rapid dimension changes are core requirements of mechanisation at van Roje, given the frequent product changes involved. A dimension change upstream of the planing machine takes around 1 minute under practical conditions and 20 seconds downstream of the planing machine, meaning each dimension change takes a total of 1 to 2 minutes. The entire mechanisation is designed to provide a feed of 200 m/min. The compact mechanisation layout can accommodate timber lengths of 8 m with ease, while the minimum length for raw material is 2.00 m and 1.80 m for planed products. Package lengths up to 8 m can also be wrapped on the package wrapping unit.

CLT marketing from May

The planing mill is not only designed for finishing the main product, but also represents an important downstream production section for the cross-laminated timber production facility under construction. B sorters for lamellas originally created in the sawmill for other products are calibrated and quality sorted here for use as top layer lamellas in cross-laminated timber (CLT). Lamellas cut especially for the top layer in the sawmill are planed directly in the cross-laminated timber plant. Raw lamellas created from side products are planed and quality sorted for use as (non-dovetailed) transverse layers in the CLT. The option to create different board widths in a layer on the planing machine really pays off here. Exploitation of side products can therefore be considerably increased.

When compared to the usual contemporary production process in CLT manufacturing, the entire production process is to be optimised for resource efficiency, from production of raw lamellas in the sawmill to the completed CLT construction element. Particular attention is also paid to the conservation of raw materials in the cross-laminated timber plant (which bears the project name “Cross Works”). Window and door cutouts are returned to the raw materials cycle again through a treatment process. The cutouts created are separated and recycled in the cross layer. These efforts to achieve resource efficiency have also encouraged support of the overall project through funding of EUR 5,993,815 from the environmental innovation programme of the German Federal Ministry of the Environment. 75,000 m³ CLT should be manufactured annually as of April in 2-shift operation. van Roje wants to begin marketing its cross-laminated timber in May.

Hobeleinzug, Planer Infeed, chargement de raboteuses

Kallfass planing machine feeder

Einzug REX Big Master Hobelmaschine

Infeed side of the REX “Big Master” planing machine

Hobelline, Planing line, ligne de rabotage

Schematic depiction of the van Roje planing mill.

Kippentstapelung, tilt destacking, dépilage par renversement

Charging and tilt destacking from Kallfass.

Bündelung, bundling, bottelage

The view into the front part of the van Roje planing mill facility. The bundling unit is in the foreground, with the feed for the first stacker behind. Visible in the background are (from the right) the sharpening center, the noice-protection cabin of the planing machine and the “Golden Eye” scanner.

Bündelung und Stapler, bundling and stacking, bottelage et empilage

The rear part of the facility, with the bundling unit in the foreground again and the line with the second stacker behind.

Graphics: Kallfass / Images and text: J. Härer, Holz-Zentralblatt

Holz-Zentralblatt Nr. 3/2022