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28 records – page 1 of 3.

Author
Orbay, L.
Date
January 2002
Material Type
Research report
Field
Wood Manufacturing & Digitalization
availability are limited and optical scanners are likely to remain the standard in most sawmills in the near
Author
Orbay, L.
Date
January 2002
Material Type
Research report
Physical Description
47 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Digitalization
Subject
Scanning electron microscopy
Scanners
Series Number
1983
W-1826
Location
Vancouver, British Columbia
Language
English
Abstract
Thirty full-length sample trees from the B.C. Interior were selected for a study to determine whether external log characteristics can predict internal log quality. The sample trees were also used to create 3-dimensional log images for sawmill simulation purposes. "LogSaw", a simulation tool with internal log defect detection capabilities, was used to explore the extent to which internal and external log quality information can improve log breakdown optimization. A model of a hypothetical sawmill producing lumber for the standard North American dimension market was created to study how lumber value recovery depends on different sawing optimization scenarios. Three sawing optimization scenarios using different levels of knowledge of internal log defects were compared to currently used sawing optimization technique:
Ideal sawing optimization - all defects within log interior are known.
Sawing optimization using only the knowledge of surface knots.
Sawing optimization using log rotation instructions based on zones of least external knot density. Simulation results have shown that it is worthwhile to “look into the log”. When compared with the current optimization technique, the sawing optimization, including the full knowledge of log interior, has increased the value recovery by 6.2%. When only the surface knots were projected into the log interior and included in the optimization, the value recovery had increased by 4.3%. Even this 4.3% increase is still a big improvement because this sawing optimization could be implemented using currently available scanning technologies and optimization software enhanced to include log surface knots. The scenario of using log rotation instructions based on predicted zones of least internal knot density did not show value recovery improvement. Including surface knots in the log breakdown optimization has considerably increased sawmill revenue; the hypothetical sawmill considered in this study, processing 400,000 m3 of log per year, has increased its revenue by $2.2 million.
Scanners, Electronic
Defects - Detection
Documents
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Analyse comparative des différents types de scanneurs d'équarris

https://library.fpinnovations.ca/en/permalink/fpipub5403
Author
Bédard, P.
Fournier, Francis
Date
February 2005
Edition
42282
Material Type
Research report
Field
Wood Manufacturing & Digitalization
Author
Bédard, P.
Fournier, Francis
Date
February 2005
Edition
42282
Material Type
Research report
Physical Description
18 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Trimming
Scanners
Optimization
Series Number
General Revenue 4497
Location
Sainte-Foy, Québec
Language
French
Abstract
On retrouve actuellement en milieu industriel diverses technologies de scanneurs d’équarris utilisant des configurations soit linéaires ou transversales pour l’optimiser le débitage secondaire. Puisque aucune donnée n’est disponible quant à la performance ou les avantages d’un système par rapport à un autre, Forintek a entrepris de réaliser une étude comparative. Un échantillon d’équarris a été mesuré dans des conditions industrielles avec trois scanneurs différents, un transversal et deux linéaires, ainsi qu’en laboratoire à l’aide de la technologie de rayon x, servant de référence. La comparaison des rendements obtenus avec chaque scanneur étudié a été réalisée par le biais de simulations à l’aide du logiciel Optitek. Comme la plupart des systèmes de positionnement d’équarris présentent un niveau de précision limité, des erreurs de positionnement ont été appliquées par simulation pour obtenir des résultats réalistes. Les résultats ont démontré que les erreurs de positionnement ont un impact majeur sur l’optimisation du débitage secondaire. Avec le niveau d’erreur moyen observé en industrie, aucune technologie de scanneur ne se démarque nettement des autres. Toutefois, en améliorant considérablement la précision des systèmes de positionnement, on pourrait observer la tendance suivante : le scanneur transversal s’avèrerait le plus précis avec un niveau d’efficacité de 2 % supérieur au système linéaire à 4 caméras, et ce dernier serait de 2 % supérieur au système linéaire à 2 caméras. La technologie du rayon x offrirait un excellent potentiel d’amélioration par rapport aux technologies actuelles puisqu’elle permettrait d’accroître l’efficacité du débitage de 6 % en ne considérant aucune erreur de positionnement.
Scanners
Breakdown, secondary
Trimming
Edging
Optimization
Documents
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A computer visualization and analysis of wet-wood distribution and related processing alternatives for subalpine fir trees

https://library.fpinnovations.ca/en/permalink/fpipub37634
Author
Alkan, S.
Date
October 2002
Material Type
Research report
Field
Sustainable Construction
Author
Alkan, S.
Date
October 2002
Material Type
Research report
Physical Description
36 p.
Sector
Wood Products
Field
Sustainable Construction
Research Area
Advanced Wood Materials
Subject
Wetwoods
Simulation
Scanning electron microscopy
Scanners
Grading
Balsam
Automatic control
Fir
Series Number
1020
W-1911
Location
Vancouver, British Columbia
Language
English
Abstract
A software, by which virtual 3-D subalpine fir (Abies lasiocarpa [Hook] Nutt) logs can be re-created, visualized, and theoretically sawn an infinite number of times, was developed. The software also facilitates obtaining data for determining quantitative variation of clear wood, wet-wood, and knot patterns within the tree stems. Results based on the quantitative calculations showed that there are two general patterns of wet-wood within the sub-alpine fir stems. The first pattern is called wet-pocket and the second pattern is called wet-streak. Wet-streak patterns are generally confined to the medullary-inner heartwood regions in the outer heartwood and heartwood-sapwood transition zones of the tree stems, mostly associated with dead knots. Wet-pocket patterns consist of portions occurring in mid regions in close proximity to the base and regions mostly around partially dead knots of the tree stems. Both wet-wood patterns usually converge at the nodes and extend along the branch axes, forming a connection with the exterior boundary only around branches. Numerical analysis of the results showed that the volume of both types is more prevalent in the lower-stem regions, becoming less prevalent towards the living crown. The radial extension of wet-wood types with radial distance from the tree centre was variable, with a maximum diameter of 22 cm. Both wet-wood volumes increased with increasing tree age and diameter class independent of age. However, the percentage of total wet-wood volume decreased with increasing DBH, increased stem height and showed no clear trend with age class. Total amounts of wet-wood ranged up to 27 per cent in individual stems. A weak relationship was found between dead knot-pattern and wet-streak pattern volumes, while a moderate high relationship was found between partially dead knot and wet-pocket volumes. A weak relationship was found between external tree characteristics and both wet-wood distributions. As a result, some promising trends emerged for a better understanding of wet-wood and knot pattern variations as influenced by tree stem locations, DBH, and age. The developed software may offer a compelling technique for assisting subalpine fir log processing decisions. However, the destructive data collection method used in this study is “error-prone”. Therefore, an interesting alternative would be the use of more accurate non-destructive scanning techniques, such as CT-scanning, to verify the trends identified here through more deliberate sampling at other forest sites. A new study is already underway to meet this need.
Moisture content
Computer simulation
Abies lasiocarpa
Scanners, Electronic
Defects - Detection
Grading - Automation
Wetwood
Documents
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Demonstration of potential improvements in log bucking systems

https://library.fpinnovations.ca/en/permalink/fpipub5500
Author
Giles, D.R.
Wang, S.J.
Munro, B.D.
Date
March 1989
Edition
37286
Material Type
Research report
Field
Wood Manufacturing & Digitalization
Author
Giles, D.R.
Wang, S.J.
Munro, B.D.
Date
March 1989
Edition
37286
Material Type
Research report
Physical Description
18 p..
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Scanning electron microscopy
Scanners
Saw mills
Efficiency
Logs
Series Number
W-946
Location
Vancouver, British Columbia
Language
English
Abstract
Logging - Bucking
Sawmilling - Efficiency
Scanners, Electronic
Documents
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Effect of internal defect information on bucking optimization

https://library.fpinnovations.ca/en/permalink/fpipub37929
Author
Orbay, L.
Date
October 2008
Material Type
Research report
Field
Wood Manufacturing & Digitalization
on external shape information obtained with different profile scanners (8). 3 Staff Laszlo Orbay
Author
Orbay, L.
Date
October 2008
Material Type
Research report
Physical Description
23 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Digitalization
Subject
Studs
Scanning electron microscopy
Scanners
Saw mills
Efficiency
Series Number
5409
W-2611
Location
Vancouver, British Columbia
Language
English
Abstract
Computer simulation was used to evaluate the performance of three scenarios of sawmill operation: 1) External Scanning at the bucking station, 2) X-ray Scanning with external plus partial internal knot scanning at the bucking station and 3) Perfect Scanning with external plus full internal knot scanning throughout the mill. Forty sample stems were scanned and stem models developed to provide input for Forintek’s sawing simulation program, OPTITEK®. Input files of both sawmill machinery and their products were developed based upon the operation of a typical sawmill in the Interior of B.C. Optimized bucking solutions were generated, and sample stems were sawn accordingly. Lumber value and volume recovery data were obtained and enabled a comparison of the performance of the three operational scenarios. The X-ray Scanner Scenario provided a 2% value recovery increase compared to that of External Scanner Scenario. The Perfect Scanner Scenario added an additional 5.5% to that of X-ray Scanner Scenario. This was due partly to improved scanning at the bucking station but more so to the internal defect detection at all machine centers in the mill. Conclusions of the study should help sawmillers in their investment decisions regarding sawing optimization improvements.
Sawmilling - Efficiency
Sawmilling studies
Scanners, Electronic
Documents
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Effect of scan spacing on trimming efficiency

https://library.fpinnovations.ca/en/permalink/fpipub37077
Author
Wang, S.J.
Date
January 1985
Material Type
Research report
Field
Wood Manufacturing & Digitalization
Author
Wang, S.J.
Date
January 1985
Material Type
Research report
Physical Description
12 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Trimmers
Scanning electron microscopy
Scanners
Saw mills
Equipment
Efficiency
Recovery
Series Number
W-289
Location
Vancouver, British Columbia
Language
English
Abstract
Sawmilling - Efficiency
Recovery
Sawmills - Equipment - Trimmers
Scanners, Electronic
Documents
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Entrées d'équarrisseuses au débitage secondaire - Phase III

https://library.fpinnovations.ca/en/permalink/fpipub39115
Author
Bédard, P.
Date
August 2008
Material Type
Research report
Field
Wood Manufacturing & Digitalization
Author
Bédard, P.
Date
August 2008
Material Type
Research report
Physical Description
22 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Scanners
Sawing
Series Number
Projet General Revenue no 4910
4910
Location
Québec, Québec
Language
French
Abstract
Cette étude a été réalisée pour évaluer la performance des technologies de débitage secondaire dans les scieries. Deux équarrisseuses-débiteuses récentes et opérationnelles ont été retenues pour effectuer des tests pratiques et simuler leur taux d’efficacité réel et théorique. Un échantillon d’équarris de 4 pouces d’épaisseur et 12 pieds de longueur a été scanné en usine, en format 3D, pour réaliser les travaux. Deux lots d’équarris similaires ont été créés pour tester les équipements et réaliser les simulations. Les technologies d’équarrisseuse-débiteuse étudiées se décrivent comme suit : les deux systèmes sont alimentés linéairement et pourvus de scanneurs 3D (caméras-laser) pour l’optimisation du débitage. L’équipement A effectue le sciage courbe naturel avec un mécanisme de pré-positionnement auto-centreur. L’optimisation du positionnement se fait en translation seulement (décentrage parallèle à l’axe de coupe). Cette machine utilise des têtes d’équarrissage coniques et des scies circulaires guidées. L’équipement B effectue pour sa part le sciage courbe calculé et l’optimisation du positionnement se fait aussi bien en alignement qu’en translation. Il utilise des têtes d’équarrissage cylindriques et des scies circulaires guidées. Le sciage courbe naturel permet de suivre des courbures plus prononcées sans restriction (R=500po), alors que le sciage courbe calculé est normalement restreint (R=1 500po), mais ce paramètre est réglable. Plus la valeur de R est petite, plus la courbe suivie est prononcée. En pratique, les deux technologies ont obtenu le même rendement et ont généré des revenus équivalents. Le taux d’efficacité des deux systèmes se chiffre à 98 % (en termes de revenus) selon le niveau de performance simulé avec Optitek. La qualité des copeaux des deux types de têtes d’équarrissage s’est avérée similaire selon les proportions de petits copeaux indésirables (3/16 po et particules fines) obtenus au tamisage. La précision de sciage en général a été excellente, l’écart-type s’est maintenu sous 0,020 pouce. Seules quelques pièces provenant des têtes coniques (équipement A) ont généré des bouts minces en biseau, ce qui a affecté la précision de sciage des pièces extérieures. Il est possible qu’un mauvais alignement de la machine en soit la cause. Un niveau de performance théorique optimal a été simulé pour les deux technologies. On assume ainsi que le positionnement physique des équarris lors du débitage, devrait se faire avec une précision de 0,200 pouce ou mieux. Si l’équipement A, en sciage naturel, était pourvu d’un système d’optimisation du positionnement en translation et alignement, son rendement aurait pu atteintre 407 pmp/m³, ce qui indique un potentiel d’amélioration de revenus de 5,1 % par rapport à sa performance actuelle. L’équipement B, en sciage courbe calculé (avec un R=1 500po), a pu atteindre 396 pmp/m³ d’où une amélioration potentielle de 2,8 % en revenus. Le principal défi des manufacturiers d’équipements est donc d’accroître la précision du positionnement des équarris lors du débitage.
Scanners
Canters
Sawing - Breakdown
Documents
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Establishing procedures to optimize mill on-line veneer stress grading

https://library.fpinnovations.ca/en/permalink/fpipub37575
Author
Wang, Brad J.
Dai, Chunping
Date
May 2001
Material Type
Research report
Field
Wood Manufacturing & Digitalization
Author
Wang, Brad J.
Dai, Chunping
Date
May 2001
Material Type
Research report
Physical Description
16 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Veneer
Scanning electron microscopy
Scanners
Plywood
Laminate product
Grading
Automatic control
Series Number
W-1763
Location
Vancouver, British Columbia
Language
English
Abstract
VGrader, Veneer Grading Optimizer, was developed at Forintek to assist mills to optimize on-line veneer stress grading operations. So far, more than 10 copies of VGrader 1.0 software have been delivered to Forintek member mills. The software can recommend the optimum grading thresholds through analyzing the properties of veneer to help mills deal with “what-if” scenarios when veneer species, log source and diameter as well as final veneer products change. By tailoring veneer grades to the market requirements of LVL/plywood products, the software serves as a useful tool to characterize specific veneer for end use and help optimize veneer on-line stress grading and products lay-up options. During the past year, the VGrader software has been upgraded to deal with either UPT-based (ultrasonic signal propagation time) veneer stress grading or E-based (modulus of elasticity) veneer stress grading or veneer visual grading. The software has also been upgraded to accommodate UPT data either from mills or laboratory testing of veneer samples. A direct linkage between laboratorial measurement span and desired wheel-span of the on-line grading system was also setup. The current version of the software is VGrader 3.0. To help mills optimize current on-line stress grading operations, the proper procedures to find the optimum UPT thresholds were established. The proper procedures are as follows: 1) Sample veneer sheets representative of veneer population in the mill and perform stress wave testing for sampled sheets using a portable stress wave timer. Alternatively, full-size veneer sheets can be sampled right after the on-line grading system with UPT data being recorded for each veneer sheet; 2) Measure other relevant veneer properties such as thickness, density, moisture and knots; 3) Calibrate the stress wave time (or UPT) to find its zero offset value; 4) Store all measurement data into a VGrader compatible database; 5) Use the upgraded VGrader software to examine the distribution of veneer attributes/properties such as thickness, UPT, density and MOE; 6) Derive required veneer MOE based on the performance requirements of target veneer products; 7) Establish stress grading constraints and using VGrader 3.0 to perform computerized veneer stress grading through adjusting the UPT or E thresholds and examining the change of statistical veneer MOE, densities and volume breakdown per grade until all the grading constraints are satisfied; 8) Convert the optimum set of UPT or E thresholds from the VGrader software into those used for on-line veneer grading system to perform stress grading; 9) Make veneer products and test them to validate the grading results. An example of establishing the above procedures was also demonstrated.
Veneers
Grading - Automation
Scanners, Electronic
Plywood - Grading
Lumber, Laminated veneer
Documents
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Exigences de performances et technologie de pointe des lecteurs optiques de marques de classement (Octobre 1987)

https://library.fpinnovations.ca/en/permalink/fpipub38127
Author
Wang, S.J.
Hailey, J.R.T.
Mayer, D.A.
McCarthy, L.
Date
March 1990
Material Type
Research report
Field
Wood Manufacturing & Digitalization
Author
Wang, S.J.
Hailey, J.R.T.
Mayer, D.A.
McCarthy, L.
Date
March 1990
Material Type
Research report
Physical Description
14 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Scanners
Series Number
E-400
Location
Ottawa, Ontario
Language
French
Abstract
Grade Mark Readers
Grade Mark Scanners
Documents
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Innovative veneer processing technologies

https://library.fpinnovations.ca/en/permalink/fpipub37668
Author
Dai, Chunping
Wang, Brad J.
Date
September 2003
Material Type
Research report
Field
Wood Manufacturing & Digitalization
Author
Dai, Chunping
Wang, Brad J.
Date
September 2003
Material Type
Research report
Physical Description
34 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Veneer manufacturing
Veneer cutting
Veneer
Scanning electron microscopy
Scanners
Recovery
Quality control
Qualitative analysis
Peeling
Series Number
3250
W-1987
Location
Vancouver, British Columbia
Language
English
Abstract
This report addresses issues about productivity, recovery and quality concerning veneer peeling in plywood mills. It was demonstrated that green veneer can be composed using a stitching technique. The maximum stitching speed was 50 ft/min which was slower than a current veneer composer. Stitched veneer did not have a significant effect on bending properties, but shear strength was slightly reduced which could be caused by the existence of stitching threads between the glueline. The roller bar diameter size had a significant influence on veneer quality. In general, peeling veneer with a 1” diameter roller bar resulted in the smoothest veneer with the most uniform thickness. The veneer thickness and roughness between 1.0” and 2.56” diameter roller bars were significantly different, but the difference in veneer quality between 1.75” and 2.56” diameter roller bars was not significant. Further, the difference in veneer quality between 1.0” and 1.75” diameter roller bars was not significant except for veneer roughness. Knife height also had a significant effect on veneer quality. Setting the knife at the spindle center proved to be the best. Veneer thickness at this setting was consistently closest to the target, and had the smoothest surfaces and smallest lathe checks. Average veneer thickness was lowest as well. While higher or lower settings created rougher veneer, higher settings were more forgiving than lower ones. For best results, the peeling knife should therefore be set at 0.0” to 0.015” above the spindle center. Incisor teeth pattern affected veneer quality. Narrower teeth and a wider gap resulted in better veneer quality in terms of veneer curl-up (flatness) and green and dry veneer thickness variations. However, the effect of incisor teeth patterns on veneer roughness and lathe checks seemed to be negligible. The validation tests revealed that an optimum lathe setting for the smooth roller bar was the following: pitch angle (PA) =89.50, vertical gap (VG)=0.425” and horizontal gap (HG) = 0.1”, and the optimum lathe setting for the incisor bar was the following: PA=90.50, VG=0.388” and HG=0.1” to 0.11” when peeling 1/8-inch veneer. The peeling computer program VPeel® was successfully upgraded to allow users to define profiles of pitch angle and horizontal gap. This feature will help the veneer product industry to define optimum lathe settings.
Recovery - Veneers
Veneers - Peel quality
Veneers - Manufacture
Scanners, Electronic
Veneers - Cutting, Rotary
Documents
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28 records – page 1 of 3.