The nearly 10 million euro modernization project of the pine sawmill located in Juupajoki, Pirkanmaa, has renewed the splitting saw, automation and other equipment in the second stage of sawing. Thanks to the change, more end products are obtained from the same amount of logs. The renewed sawmill equipment includes three band saw lines, with a total of 12 band saws. The saw blades are also thinner than before – this reduces the amount of sawdust in particular and also improves the raw material utilization ratio.
The advent of laser and X-ray technology, as well as artificial intelligence, has moved humans into the control room.
"What's new is laser measurement of logs and machine vision. Our control room has a wall of monitors from which we monitor the process," says the sawmill operator. Antti Markkula.
The division of labor is based on the different data processing capabilities of humans and machines. Humans do not have time to understand the avalanche of data generated by the process.
Markkula points out that artificial intelligence operates within defined limits, and any deviation from these always requires acknowledgement from a human operator. Limits ultimately ensure safety and rational production, among other things.
The AI collects data, analyzes it, and sends it to the operator for approval or rejection. For example, if the limit values that determine sawing are changed with the operator's approval, the AI learns from experience.
A modern sawmill can handle three operators.
“We have two edge lines and one operator takes turns sawing. Sometimes there are congestions, so someone has to go and clear them. Sometimes we also have to clean debris from the photocells or reorient the cameras on the line.”
Otherwise, the work is largely about observing the sawing process, which is handled by artificial intelligence.
“We also have to deal with it quickly if the wrong goods start arriving. Thousands of pieces can arrive in half an hour.”
X-ray-passing logs
The quality of logs is no longer assessed visually; X-rays reveal the condition of the wood faster and more accurately than humans can.
Every log that goes to sawmill is scanned and a 3D model is created. The image shows the shape of the log and its weaknesses, including knots and possible foreign objects and stones.
During the scan, which takes less than a second, a large amount of data is collected from the log, which the artificial intelligence utilizes throughout the log's journey through sawing to end products. At the beginning of the journey, the log is also automatically rotated to the optimal position for sawing.
Artificial intelligence, among other things, calculates how a log should be sawn to ensure that the wood is utilized as efficiently as possible without waste. Machine vision also checks the boards, revealing possible errors, such as cracks.
