Sophisticated Scanning System Significantly Increases Log Yields
Even though Piveteau Bois still has logs stacked at their log yard, the staff of the large-scale sawmill actually view the woodpiles as a virtual lumber yard already. This approach has changed the entire production process for the French company; before cutting even starts, they already know exactly which boards they will get out of the logs. This is made possible by means of the CT Log and the one-of-a-kind fingerprint system provided by MiCROTEC.
The Piveteau Bois sawmill in Sainte-Florence near the French Atlantic coast has several different mainstays. Only a small part of its cutting volume is sold fresh, the rest is dried, planed, glued or otherwise processed. Pine, Douglas fir and spruce wood are used to make wooden floors and facades as well as glulam and CLT elements. In the manufacturing of these products, Piveteau Bois pays particular attention to the optimum utilization of roundwood. “Our sawmill in Sainte-Florence is located in a region with few wood sources. This makes the raw material even more valuable,” R&D Manager Ugo Gerard explains, referring to the unconventional location for a sawmill far from large forest areas.
Against this background, the company implemented numerous optimization measures in recent years with the aim of increasing the log yield step by step. The collaboration with MiCROTEC has been particularly close and equally fruitful. In the sawmill alone – from log infeed to lumber sorting – the scanner specialists from South Tyrol implemented three systems that optimally complement each other.
Directly after the log infeed, the long and short logs are brought into the CT Log at feed rates of up to 120 m/min. The computed tomography technology integrated in the machine enables the digital reconstruction of the logs’ complete inner life. Specifically, a comprehensive three-dimensional density profile of each log is created which primarily shows the size, position and condition of knots. Furthermore, the system detects whether there are rotten knots, cracks, resin pockets or spiral grain. “This allows us to precisely predict the quality of the boards and their corresponding location even before cutting, and to adjust the sawing schedule accordingly for each log. Essentially, this means we are no longer accessing the individual logs for cutting but our virtual lumber yard within the logs,” Gerard explains and adds that this has changed the approach to the entire production process. “We now know exactly which logs to use for which products, and what volumes of the various assortments we can produce each year. This not only increases the value of the used wood but also facilitates the logistics for the markets.”
Recognize and Rotate
Directly before the sawing line, the logs are passed through the Logeye 302, a multi-sensor quality scanner with fingerprint. Equipped with X-ray technology, multi-sensor cameras and other sensors, the Logeye performs a 3D measurement of the log and again determines its density profile. With the density profiles of the logs – each being as unique as a fingerprint – each log is recognized and rotated according to its optimum value yield before cutting. “We are optimizing the sawing schedule for each individual log,” Gerard emphasizes. In addition to the Microtec scanners, this is made possible with the help of a modernized profiling line from Linck, designed to adjust to every single log which would even allow for a completely unsorted cutting process.
Full Traceability of the Boards
The third MiCROTEC system is the Goldeneye 900 multi-sensor quality scanner in transverse transport. It is responsible for quality grading of the fresh boards as well as the definite identification of each lamella. Thus, Piveteau Bois can recognize and allocate each log and each board by means of this digital fingerprint. This results not only in added value, but also the full traceability from board to log.
“In the past, when we did not know in advance what we would get out of each log, we had to put some boards to a lower-value use than originally planned. Today, the rate of this unwanted downgrading is effectively zero,” Gerard reports, adding that this has increased the value output of each log by 5%.
A great result, but one that doesn’t lead Piveteau Bois to sit back and relax – quite the opposite, in fact: “To keep getting better, we are continuously working on new projects, and MiCROTEC is a reliable and trusted partner that keeps pushing us forward with new ideas and innovations.” MiCROTEC will be presenting the next evolutionary stage of the fingerprint system at Ligna 2023 in Hannover, Germany.
Directly before the sawing line, a Logeye 302 scanner recognizes the logs which are then rotated into the optimal position
The Goldeneye 900 multi-sensor quality scanner grades the fresh boards and allows for full traceability all the way back to the log
Melanie Kaindl, Head of Marketing, and Fabien Iffrig, Area Sales Manager of Microtec, together with Ugo Gerard of Piveteau Bois (from left to right)
The 3D density profile shows the size, position and condition of knots in the log. Cracks, resin pockets and other wood defects are also detected