At Hoffmann Trade, the diversified product lines are produced with a flexible band saw. The sawn timber warehouse and the two Mühlböck drying chambers, that are positioned 15 m above the saw hall are used for further processing. Two planing lines are located here. In June 2011 Hoffman invested in a new Weinig Powermat 2500 with a Kallfass mechanization. Kallfass was able to supply a complete package: Destacking, infeed to the planer, stacking with automatic batten arrangement, and the control system. Moreover, multi-chopping, batten bundling and automatic package strapping are also included in the Kallfass planing mechanization. The sawn timber packages are automatically destacked via a tilt table, and can optionally be moved over a moisture measuring unit.

There are two possibilities for the timber route

A sorting point upstream of the planer offers the possibility of outsorting two qualities. The timber is continuously cycled into the Weinig planing machine. Capacity was specified at a maximum of 50 pieces per minute - with a timber length of 2.1 to 7.8 m. The boards fly through the system at a speed of up to 200 m/min. After planing, two options were provided for the different products at Hoffmann Trade:

Option 1:

The planed goods can be stacked with the automatic batten bundling unit and bundled into finished packages. The finished packages are then chopped to the desired length in the multiple cross-cut saw. From this point the timber moves further via the stacker.

Option 2:

The planed goods can be moved through the multiple cross-cut saw directly in layered processing, and stacked up with intermediate strips.

Currently two strapping units are installed in the bundling system. “However there is also the option to install two additional strapping units. In this case a middle saw could also be integrated in the bundling”, explains Stefan Günther, project manager at Kallfass. The multiple cross-cut saw has five chopping saws that can all be moved automatically. The eight batten magazines in the stacking system are also automatic, as specified. The stacking capacity is configured at twelve layers per minute.

Holzkurier number 09 2012

In the planning, notching capacity was specified at 120,000 solid cubic meters a year.

Jerusalem pine is processed - due to its special growth, it is a type of wood that is not entirely without concerns.

For the equipment, Pinhoser owner, António Fernandes, relied on German technology (see Holzkurier Heft 33, page 10-11): Linck delivered the profiling line, Kallfass, Baiersbronn-Klosterreichenbach/DE, was responsible for stacking of the main boards and side boards. In addition, machines from Holtec, Jörg-Elektronik, Liebherr, Vecoplan, and Vollmer are in use.

First the side boards

“With our sorting and stacking systems, for an eight-hour shift, and 250 work days a year we guarantee availability of 75%, explains Ernst Hauser, project manager at Kallfass. The lengths of main board and side board were defined as 2 to 3 m. In the profiling line, an average of 22 cut-offs per minute can be sawn.

Per trunk, up to four side boards are possible - depending on the diameter and cutting pattern, up to 88 boards per minute accrue.

In a separate sorting unit, the side boards are separated and pulled off - in the notch direction to the left. The controller divides boards into two Kallfass stacking systems. “The inner side boards, as a rule, these are the broader and better dimensions, go to stacker system L3-1. The dimensions of the side boards have been specified at 15 to 40 mm in thickness and 60 to 200 mm in width”, continues Hauser. The outer side boards are pulled off for stacker system L3-1a. Scrap is discharged at a third point.

Upstream from each of the two stackers, a transverse notching unit with three circular saws for end-cut and middle cut are installed. Kallfass specifies the capacities of the stacking systems; for the L3-1 at ten to twelve to layers per minute, for the L3-1 at eight to ten layers per minute.

“Pinhoser sells most of the side boards on the domestic market, the main boards are for export, for example to Spain or Africa”, reports Kallfass’s project manager for Pinhoser.

Main boards go on three lines

The main boards are split into pallet boards with the Linck multi-blade circular saw CSMK 285-A1. The boards are individually “peeled off” with a Kallfass device and transported on a chain conveyor, and straightening roller conveyor for sorting. An employee evaluates the boards and has the possibility of selecting three stations for the main boards.

“Poor quality, such as boards with two much wane edge, go via pullout rollers to a scanner for a subsequent evaluation.

Based on the stored assortment the scanner determines the best possible yield. “With a multiple crosscut saw, another one or two boards can still be generated and thus the best possible can be obtained from all goods”, assures Hauser. The boards are packetized with the L3-3 at eight to ten layers per minute. Scrap goes to a central disposal unit. The second main board stacking (L3-2) is reserved for thicker cross-sections, such as squared timber. Like the other stations, this station is equipped with a multiple crosscut saw and has the same capacity as the L3-3, at eight to ten layers per minute.

The best comes at the end

The main board sorter L3 is the highest capacity Kallfass system at Pinhoser. “With all other installed machines the boards are sawn individually with the crosscut saw”, explains Hauser. “With the L3, we guide the boards layer by layer through the machine”.

An additional particularity is integrated in this line: “To reduce the effort associated with impregnation, we have installed this step right in the transverse transport, upstream of packet formation. Thus the wood is guided through an impregnation curtain”, summarizes Hauser. With the L3, packetizing is executed in 14 to 16 layers per minute. “As opposed to the other systems, the L3 is equipped with batten magazines.

In addition, offset stacking is possible, which produces extremely stable packets.” And for the final step, the packets are strapped and provided on a roller conveyor for removal transport. Each stacking layer is configured for a maximum packet size with a cross-section of 1200 x 1200 mm, and a length of 3 m.

“The complex distribution of the boards was a challenge that we mastered to the satisfaction of the customer”, Hauser is pleased to report.

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Holzkurier number 47/2011

Sawmill in sawmill

In one and half to two shifts Egger operates a planing mill, in addition to the high capacity band resaw. The system is arranged under the multi-level sorter. “With the Waco twin resaw we can further refine the wood, i.e. divide the sawn timber again and sell it in a different quality or as a different product. Thus we increase yield, use the wood in the best manner possible, and achieve an added value”, explains Atschreiter, citing the reasons for this investment.

The mechanization is supplied by Kallfass Baiersbronn-Klosterreichenbach/Germany. In the design phase we ensured that the level of automation would be increased. “For example, currently one employee de-stacks the packages layer-by-layer with a vacuum lifting device.

With the momentary quantities this is fully sufficient. However at any time we can integrate a lift table in the infeed”, explains Atschreiter.

The boards are straightened out and fed into the twin resaw via a transverse conveyor. Because timber is divided based on width as well as thickness, at Egger a special guide (see photo above) is integrated in the infeed. Thus even narrow timber is securely held in position.

Diagonal or straight

The maximum cross-section that can be processed with the system is 400 x 300 mm. A diagonal cut to 15° in automatic mode or to 45° with a manual set-up aid is possible. “For diagonal cuts the entire infeed part can be adapted in height by approximately 60 m”, explains Hans Haist from Kallfass. The capacity of the system is 60 m/min or 25 pc./min. As a special solution at Egger small board stacks can be formed automatically and these can be divided into batten groups in the resaw, and the battens are bundled manually.

The divided goods are stacked at two stations: The goods are automatically packetized via stacking tongues. Thanks to a simple outsort possibility via conveyor belt the goods are stacked by hand at a second location.

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Holzkurier number 35/2011

We look forward to your visit on our new stand in Hall 27 Stand D42

Visit us in Hall 27 Stand D42

Holzkurier Ausgabe 51 2010