Make the First Cut Count
A technology review of the latest options in log infeed, scanning, positioning and canting.
Much of the recent investment in the lumber sector of late has been in the planer mill. That makes sense, as reasonably moderate investment in optimized grading has been garnering rapid return on investment (ROI). Still, when the market recovers, fibre availability will again be key and lumber supply will quickly become tight, making the recovery and production gains available from the latest generation of primary breakdown systems crucial. As a result, Canadian Forest Industries brings you this update on primary breakdown technology, including optimization and log positioning.
|USNR recently redesigned the SL3000 Log Breakdown system. The result is compact, fast and accurate, and is capable of operating at 600 fpm and processing 24 pieces per minute.|
|The HewSaw SL250 can run at speeds exceeding 500 feet per minute.|
Sawmill equipment companies are always taking a hard look at all of their products, tweaking or even revamping designs on an ongoing basis to better suit them to evolving customer needs. Recent updates to primary log breakdown systems focus on providing more compact and streamlined models – using new ideas and the best features from previous systems to create their best offerings to date. Here’s a look at what’s changed in the past few years.
USNR recently redesigned its SL3000 Log Breakdown system, which is capable of operating at 600 fpm. The compact, hybridized design, which can handle logs up to 30 inches in diameter, is already installed at two west coast mills. According to Colleen Schonheiter, USNR’s senior marketing associate, the mill at Stimson Lumber in Tillamook, Ore., features a log feeder, positioned at the last step of the log loader. It gently loads logs onto the vee-flight chain. The rocking motion of the log is minimized and this allows the system to control the gap between logs. After the first scan, the reciprocating quad roll log turner actuates turning and positioning while the log is still held above the sharp chain. This feature offers a big advantage by allowing the line to position for specific log defects to achieve maximum recovery. After positioning, the log is scanned again, and the chipping heads are moved if needed. With this infeed concept, there is no transition into the canter so there is limited opportunity for the log to lose position prior to processing.
USNR’s primary breakdown machines use the company’s MillExpert optimization platform with Smart TriCam lineal scanning as the base offering; LPL-E sensors for gathering maximum 3-D data density are also available. Their Precision Geometric Log Rotation (PGLR) system monitors and corrects the rotation process in real time and typically reduces rotation error by 50% or more. For real-time process monitoring and trending, USNR also offers “Turn Detector and System Quality Inspector” software, providing faster initial system tuning and feedback on overall system performance – long-term tools to predict maintenance requirements. USNR also has a brand new compact four-sided canter primary breakdown system rolling out this year. Its conical canter head design minimizes the snipe inherent in chip-n-saw style four-sided canters. The first installation of this system will be at a mill in Russia later this year.
|The HewSaw Login Optimized Log Positioner and the R200 at Vaagen Bros. in Midway, B.C.|
|Pictured is a profiling unit (four profiling chipping heads) in front of a Comact Cetec band mill, taken at Scierie Dion in Saint-Raymond, Que.|
|Inotech’s new primary breakdown infeed, including the log rotator, the vertical belt infeed and the canter. Recently, one unit was sold to Miramichi lumber in New Brunswick and another will be installed at Industries TLT in Quebec later this summer.|
HewSaw Machines’ largest primary breakdown line is the SL250, which can handle logs up to 21.5 inches in diameter. Running at speeds exceeding 500 feet per minute, the SL250 can be configured to include a chipper-canter, cant saw, ripsaw, and optimized edging capabilities. HewSaw is currently installing an SL250 line at the Sandy Lane mill in Bombala, Australia, while another unit has been ordered by U.K. sawmilling company BSW Timber for its Fort William mill in Scotland.
Here in North America, Pacific Northwest lumber manufacturer Vaagen Bros. is ramping up production with a HewSaw R200 and a HewSaw Login Optimized Log Positioner at its Midway, B.C., sawmill. “This smaller HewSaw can exceed speeds of 650 feet per minute and can handle logs up to 13.5 inches in diameter,” Bill Tice, HewSaw capital sales/marketing manager, says. The Midway mill, which was shut down prior to the recent installation of the HewSaw, was historically a three-line mill. This new HewSaw has replaced all three lines. Vaagen Bros has another R200 at its Colville, Wash., mill and an R200PLUS at its Usk, Wash., plant.
Many North American mills are updating the infeed to their existing HewSaw breakdown machines with the HewSaw Login Optimized Log Positioner. This configuration allows a single in-line true shape scanner to calculate log rotation and optimize the pattern selection for maximum recovery. The latest introduction to HewSaw’s lineup is its R200 CC, which is designed specifically as a chipper-canter. With fewer internal components and hydraulics than the fully equipped HewSaw machines, the R200 CC is a cost-effective alternative for companies that only need to produce cants and chips, and is ideal for bioenergy.
During the last five years, Comact has developed a new log positioning system for primary breakdown called the OLI-CS3. The company has installed 15 of these systems over the last four years. “This new infeed can be used for small to large log applications,” Éric Michaud, vice-president of Comact’s sales and marketing, says. The compact design fits in most of the existing sawmill buildings, which was not the case with the
traditional double length infeed that was used in the past. Among other features, it’s a much-enhanced processing power, which allows reduction of the infeed length by almost 50%. In addition, the new Dual Quad core computers have enabled Comact to add a new infeed feature: the log rotation corrector. It allows the log turner to do the correction on the fly when the logs are not exactly where requested at first by the optimizer.
“As we all know, logs are not perfect – sweep, flare butt, big knots, bumps, etc. – and at the speed we go today, sometimes it requires a little fine-tuning to be right on,” Michaud says. Another process feature that Comact developed recently is the capacity to profile the side boards right on the saw line to avoid the edging process on another machine and remove the pressure on an existing machine. Comact is achieving excellent results from a recent project in Quebec relating to this feature.
The latest primary breakdown system from Inotech Fabrication is an optimized vertical belt infeed design. “Our customers asked for a very low-maintenance system that will have nearly no downtime, in addition to high-valued optimization,” Yves Lévesque, Inotech president, says. This new system includes a V-flight scanner conveyor, a tandem double-roll log rotator, a vertical belt infeed and a canter, all coupled to a 3-D scanner optimizer.
The V-flight conveyor is designed to be as quiet as possible and to be maintenance-free, thanks to its new replaceable UHMW laser-cut flight. The log rotator uses a tandem double-roll configuration for achieving precise rotation, and an automatic lubrication system takes care of the mechanical components.
However, Lévesque says, the most interesting part of the Inotech primary system is the vertical belt infeed. “Some customers ask to have very simple equipment that does not require complicated alignment. The Inotech exclusive design allows for perfect centring of the log due to the innovative design of the swing arms, and provides incredible traction and maintains control at high speed. The beauty of the system is there isn’t any automated sequence to make it work; it is all on pneumatic suspension,” he adds.
The infeed equipment is also coupled to an innovative canter design. One of the benefits of the canter is the exclusive quick-change bearing housing. This feature allows the whole canter assembly to be changed in a very short time. The canter can be coupled to band saws or circular saws. This new system is in operation at a New Brunswick mill, and another one will be installed at a hardwood mill in Quebec this summer.
Porter Scanning and Optimization Update
“Porter now offers new features with their RT3 Primary and Secondary Log Breakdown Optimization system,” Rob Della-Schiava, Porter’s account manager, says.
The RT3 Face Checker measures actual opening faces produced by primary breakdown machines and compares them in real time to those predicted by the primary breakdown optimizer. Using predicted and actual cant face and log geometry data, RT3 detects and reports on the results of mechanical and control shortcomings. This method produces significantly more comparison data than traditional hand measurement methods, allowing timely intervention should process parameters exceed mill-configurable alarming limits, improving lumber recovery and value, and machine performance.
With its RT3 Grade Scanning system, logs are scanned in front of an automated log turner or directly on a primary breakdown infeed. High-definition scan data from Hermary SL laser scanners is utilized to build a complex 3-D computer log model that now includes mapped surface irregularities with other standard geometrical data. Porter’s RT3 Rotation Correction system is designed to reduce errors associated with log rotation systems. This type of correction is becoming increasingly important with the advent of positioning infeed systems that do not re-optimize after the log is positioned and prior to processing.
|Autolog’s log scanner frame.|
Autolog recently supplied two complete log breakdown lines, as well as a new edger and trimmer-optimizer, to Produits Forestiers Temrex, an SPF random mill in Nouvelle, Que. “Autolog took this opportunity to implement many innovations to its log breakdown optimizer and control systems,” Gabriel Payant, AutoLog’s sales manager, says. For example, the scanners used for both lines (Hermary SL-1880) are used to scan both the logs and the cants, thus reducing the spare parts inventory needed. The units are also housed in a rugged frame for maximum protection.
“The engineering and the filtration algorithms were redesigned from scratch using a more modern approach. “An important factor for the customer was to be able to calibrate the scanners, modify or verify parameters remotely anywhere in the mill,” Payant says, adding that, “now all the new Autolog systems are offered with a remote interface linked to a Wi-Fi network.” Both lines at Temrex require only one operator.