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Tech Update - Grade Optimization

By Diane Mettler

The Algis Corporation
Algis is a leader in transverse lumber grading. With an Algis system, there are no mill flow changes required or daily maintenance. The company offers planer mill systems, sawmill sorts (random length, width and thickness) for clears, shop and dimension, as well as wane-up systems for planer infeed and edger optimizers. In addition, the company’s End Scan technology is said to be ideal for six-sided grading.

Autolog Inc
At Autolog Inc, planer mill optimization development is a never-ending process. The 2008 Autolog linear planer optimizer features the TrueColor HD visual defects scanner, providing quality images to Autolog’s improved grading software. This gives Autolog unbeatable precision for split and biological defect detection, the company says.                 

The new Autolog linear planer optimizer offers high accuracy and is on grade without manual input from graders. The geometric and visual defect scanners share the same scanner box in the middle of the machine. The module slides in and out for easy maintenance and cleaning. Since they have the same footprint, existing machines (more than 90 already installed) can be easily retrofitted by changing only the central scanner box.

Coe Newnes McGehee
Coe Newnes McGehee’s linear high grader (LHG) is grading bug-killed lumber on planer mill lines at West Fraser Timber. The LHG automated grading system detects and classifies characteristics such as size, wane, skip, planed bark, knots, stain, splits and shake, pith location, moisture content, strength and more. The LHG’s performance on grading bug-killed lumber was initially proven in operation at West Fraser’s Fraser Lake, BC division.                                   

Coe Newnes McGehee is installing a new planer mill at West Fraser’s Quesnel, BC, operation and it includes tilt hoist infeed, refurbished planer, revolver lug loader, SEC PosiLock positioning fence, multi-saw trimmer with precision end trim saw, 56 vertical bin pusher lug sorter with live bin walls, electric bellcrank stacker with vacuum lath placer, a separate prime stacker line for stacking premium lumber, package outfeed line with quad paper feeder and cutter, and package re-entry line. The automated grading orders for West Fraser include the E-Valuator MSR grading module that offers non-destructive, high yield MSR production from the challenging bug-killed fibre.

Comact Equipment, Inc
GradExpert is a completely automated wood classification system, requiring no assistance from a grader. It performs the equivalent work of three to four experienced graders and easily manages more than 13,000 boards per hour with a margin of error of less than two per cent. And the GradExpert will reach its profitability break-even point in less than ten months, says the company. Integration into an existing production line is easy. It takes approximately ten days for line operators to be trained and for GradExpert to reach its maximum performance. And thanks to its clean lines and strong construction, it requires minimal maintenance.                                   

The system allows full grading in: SPF, SYP, Douglas fir, hemlock and white pine. The stable transverse scanning ensures accurate measurement of bow, crook, twist, skip and wane. The vision system also provides an accurate detection of knots, pith, blue and red stains, decay, bark pockets, paint marks (MSR/wet), splits, shakes and worm holes. And there is no need for additional marking or recognition systems.

The Softac-INX OptiGrader planer grader/optimizer offers linear four-sided, true-colour visual and complete geometric scan for all knots, defects and geometric properties. It has high scan resolution and pixel depth, and an unlimited number of grades and optimization choices, including cut-in-two. It’s easy to set up and takes up little space, says the company.                 

The scanner doesn’t require board turners or hold down rolls, it can be close-coupled with the planer, and it includes full reporting and tally features. The scanner has military-grade data processing power and patented technology. Mills benefit from reduced (and possibly the elimination of) human graders, comprehensive feature identification in highspeed planer applications, and higher accuracy than transverse systems.

JoeScan has introduced the JS-20 WX scan head, a wideangle laser scanner, which delivers accelerated and precise profile measurements for transverse scanning of boards and cants. It is the latest in the JS-20 series developed by JoeScan, a leading manufacturer of laser scan heads for sawmills and other wood products applications.                                   

The JS-20 WX is capable of 650 profile measurements per second, with each profile containing up to 243 data points, and it is substantially faster, collecting as much as 10 times more data than the typical multipoint scanner, says the company.                                   

The scanner provides accurate length, width and thickness measurements of board and cants, using one type of scan head. The transverse scans provide total surface coverage and improve recovery rates. With points located every 1/8 of an inch, the scanner provides more data and detects finer details and defects. It’s also said to be easy to install.

LMI Technologies Inc
The DynaVision chroma+scan 3300 sensor integrates highdensity 3D differential profiles, light curtain functionality, and true colour vision for a simple and easy to use scanning solution. This field proven sensor allows OEMs to make higher value optimization decisions to improve lumber grades, increase yield output, and reduce material waste. The DynaVision chroma+scan 3300 has been designed with specific features to give an unrivaled amount of profiling information, true differential scanning, and colour vision for defect detection.                                   

LMI Technologies is a research, development, and manufacturing organization specializing in machine vision applied technologies.

Lucidyne’s GradeScan has completed a rigorous development and testing period in five planer mills. These mills each process one or more species including SYP, SPF, white fir, plus green and dry Douglas fir. These are 2” dimensional lumber grading applications with sizes that range from 6’ to 28’ long.                                   

Four systems scheduled for installation this year will add hemlock, common grades, 4” to 6” thick dimension and timber grades, with lineal speeds of up to 3,600 ft/min. GradeScan utilizes several sensor technologies to grade lumber. It can be installed immediately behind the planer and uses only 40” of space. The scanner grades knots, wane and other defects, leaving most mills with one check grader.

MPM Engineering Ltd
MPM Engineering has been a supplier of state-of-the-art scanning and optimization systems for 25 years. Using the latest generation of true shape scanners, MPM’s bucking, log sorting and breakdown optimizers can detect flare, pistol grip, nodal swells, catface and kinks. And grades can be assigned to the logs through the use of this data for optimization and reporting purposes.                                   

Using the scatter and/or grayscale data in combination with the geometrical data, MPM can detect and measure bark so that a more accurate underbark image can be used for optimization purposes. The same scatter/geometrical data can also be used to detect, grade and optimize for knots and other defects in the company’s primary breakdown and trimmer optimizer products.

For 35 years, Metriguard has added value and profit for its customers by specializing in grade optimizing equipment. Its Model 7200 HCLT provides the highest-grade yields in all classifications of machine-graded lumber. MSR also offers producers increased profits by improving grade recovery. Leading the way with speeds exceeding 3,000 ft/min, the machine can effectively sort by responding to grain angle, microfibril angle, and moisture content for a more reliable product. With an unmatched correlation coefficient of r2 > 0.98, Metriguard equipment produces the most accurate bending stiffness measurements, says the company. New improvements, such as Metriguard’s symmetric bar calibration feature, allow for tighter control of the calibration process that will permit reduction of grade thresholds with increased yields.

VAB Solutions
VAB Solutions Inc has come up with an innovative idea to solve inline grading problems. The company’s unique 3D lineal optimizer now acquires additional capacity with bark and colouration detection features. The bark detection feature allows mills to take full advantage of the wane dip rule by efficiently detecting dressed bark wane. The system’s colouration detection allows mills to consistently provide the colour selection and visual characteristic requested by their most difficult customers. VAB Solutions Inc is also introducing its new transverse warp measurement system. With minimal footprint and maximum accuracy, this device will guarantee outstanding grading and serve as an indispensable drying quality indicator, according to the company.

Wood scanner manufacturer and distributor WoodEye is going one step further in providing new technology in the sawmilling industry. With 20 years experience and almost 300 installations worldwide in inspection, grading and optimization of sawn lumber, recent product development efforts have been aimed at high speed planer lines and grading challenges to meet the efficiency and quality demands set by sawmills.                                   

A full-fledged edger with quality optimization is the next product release. The optimization handles a combination of quality and volume, for optimal yield. Many sites are challenged with keeping qualified personnel to sort and grade lumber at high speed. With WoodEye, the defects are detected by combining different sensors such as colour, grey scale and grain direction. The scanner also has the ability to discern nuances in order to sort the wood into different grades for stress grading, and to sort hardwood products or cross cut wood into clear blocks to make fingerjointing products, moldings and boards.