Weyerhaeuser Company Limited

Weyerhaeuser Nr Company

Other

Mark A Stanish

Stan L Floyd

Herbert D Muise

Stanley L Floyd

John E Jones

Chih-Lin Huang

Steven M Cramer

David N Bogue

Susan K Kaluzny

Thomas J Taylor

David C Slaughter

Tom J Taylor

John N Giovanini

A method of sorting green lumber is based on a ratio of moisture content to either weight or density. The moisture content of each piece of green lumber is measured, and the weight or density of the green lumber is measure. One more thresholds of moisture content to weight or density ratios are used to divide the green lumber into groups. Such a sort tends to produce groups of green lumber that require similar kiln drying schedules.

Sorting green lumber

The present disclosure includes a method for quantifying contribution to overall variability of moisture content in wood products and associated computer software. The method comprises the steps of obtaining moisture content data for the wood products and identifying one or more sources of variability in the moisture content data. A contribution to overall variability from each of the one or more sources of variability is then quantified. One or more opportunities to impact the overall variability are then quantified, each of the one or more opportunities being associated with one or more executable steps.

Method for reducing overall variability of moisture content in wood products

Methods for reducing warp potential of lumber derived from a raw material, such as a log or stem are provided. The methods involve examining the log or stem for shrinkage properties and/or properties of spiral grain. The location of the shrinkage properties and/or properties of spiral grain determine how the log is oriented relative to a cutting device. In another embodiment, these characteristics determine what cutting pattern is selected for creating the lumber. In the case of a stem, these characteristics determine how the stem will be bucked.

Method for reducing warp potential within lumber derived from a raw material

Methods are provided for predicting warp of a lumber product at a given condition, such as relative humidity, temperature, moisture content, or the like. Note that this methodology may apply to any of crook, bow, twist, cup, or combinations of these quantities. The method involves measuring an original warp of a first wood product at a known condition; changing the condition of the first wood product to a new condition; measuring a second warp of the first wood product at the new condition; developing a prediction model based on data from the original warp and condition and the second warp; measuring an original warp and condition of the given wood product; and inputting data from the original warp and condition of the given wood product to the prediction model to determine warp at a given condition.

Methods for predicting warp at a given condition

The present disclosure includes a method for optimizing value of current wood products dried in one or more current drying processes and associated computer software. The method comprises the steps of obtaining prior wood product data for prior wood products dried in one or more prior drying processes and generating a value function based on the prior wood product data. The method further includes identifying one or more sources of variability in the prior wood product data and quantifying a contribution to overall variability from each of the sources. The value function and the contributions to overall variability may be used to quantify one or more value opportunities associated with each the one or more sources, each value opportunity being associated with one or more executable steps for improving the one or more current drying processes.

Method for optimizing value of wood products dried in a drying process

The present disclosure relates to methods for reducing warp potential of lumber derived from a raw material, such as a log or stem are provided. In some embodiments, the methods involve examining the log or stem for shrinkage properties and/or properties of spiral grain. The location of the shrinkage properties and/or properties of spiral grain may be used to determine how the log is oriented relative to a cutting device. In some embodiments, these characteristics may determine what cutting pattern is selected for creating the lumber or how a stem is bucked.

Method for optimizing stem merchandizing

Methods are provided for using light reflection patterns to determine various properties of fibrous materials, such as wood. More specifically, the present invention relates to methods for determining a dive angle for grain. Further, the present invention relates to methods for using information in Tplots, combined with knowledge of the microstructure of a wood sample surface, to find pith location and/or ring curvature.

Methods for using light reflection patterns to determine location of pith and curvature of the annual ring

Methods are provided for predicting warp of a wood product given its differential characteristics, such as, for example, curvature. The methods may involve measuring at least one original warp profile for each of one or more first wood products; measuring one or more inputs on the one or more first wood products; converting the warp profile, for each of the one or more first wood products, into a differential characteristic profile; developing a prediction algorithm based on the one or more inputs and the differential characteristic profile; measuring one or more inputs of the given wood product; inputting the one or more inputs of the given wood product into the prediction algorithm; and determining a differential characteristic profile for the given wood product based on the prediction algorithm.

Methods for predicting dimensional stability of a wood product based on differential characteristics

Methods are provided for using light reflection patterns to determine various properties of fibrous materials, such as wood. More specifically, the present invention relates to methods for determining a dive angle for grain. Further, the present invention relates to methods for using information in T2 plots, combined with knowledge of the microstructure of a wood sample surface, to find pith location and/or ring curvature.

Methods for using light reflection patterns to determine diving angle of grain

Systems and methods are provided for detecting the potential of a wood sample, such as a board, to stay on grade, i.e., resist warp, after it is put into service and/or its moisture has re-equilibrated with the surrounding environment. The systems and methods include various sensor technologies and subjection of obtained data to various models, algorithms, and/or other mathematical formulas.

Methods for determining dimensional stability of wood products utilizing single and multiple sensor groups

Methods are provided for estimating the dimensional stability of a wood product from simple algebraic functions of moisture, shrinkage rates and grain angles observed on outer surfaces. The methods may employ single or multiple sensor group measurements. The quantitative relationship between crook or bow stability and lengthwise shrinkage can be established using mathematical operations, rather than sophisticated and complicated finite-element modeling methods. In particular, the curvature of any board length-segment or section, expressed as the second derivative of the crook or bow profile, can be determined from a linear combination of the shrinkage values of the coupons including that segment or section. The overall crook or bow profile of the board can be determined from a section-by-section double-integration of those second derivative values.

Methods of estimating the dimensional stability of a wood product from simple algebraic functions of moisture, shrinkage rates and grain angles

Embodiments of the present invention quantify lengthwise shrinkage to a higher degree of accuracy over currently known methods by employing reactive force values, such as stiffness measurements, in conjunction with motive force values, such as chemical composition, of the wood product.

Methods for quantitatively determining lengthwise shrinkage in wood products

A method for determining crook potential of wood is described. One embodiment comprises nondestructively obtaining lengthwise shrinkage rates (from a third party or by direct measurement) of wood and then determining crook potential of the wood based on the lengthwise shrinkage rates. Where the wood comprises lumber, lengthwise shrinkage rate measurements typically are made on at least one major planar surface of the lumber. The method typically comprises determining lengthwise shrinkage rates two or more measuring points separated by a predetermined distance, such as at substantially one-foot intervals along the lumber. Particular embodiments of the present invention determine lengthwise shrinkage rates using infrared radiation, microwave radiation, electricity, ultrasound energy, and combinations thereof Working embodiments of the method use ultrasound energy to determine lengthwise shrinkage rates. For example, one working embodiment measures the speed of an ultrasound pulse through wood to determine the modulus of elasticity (MOE) of the wood which can then be correlated to the lengthwise shrinkage rate. In another example, lengthwise shrinkage rate can be determined from the speed of an ultrasound pulse using an empirically derived formula, such as an exponential formula. Another embodiment of the present invention comprises determining crook potential of wood based on non-averaged lengthwise shrinkage rates. Another embodiment of the present invention comprises determining crook potential is determined using a finite element model (FEM). The method the present invention provides can determine crook potential that correlates with actual measured crook with an R,value of at least 0.5.

Method for determining crook potential in wood

A method for determining warp potential of wood. One embodiment comprises nondestructively obtaining lengthwise shrinkage rates and grain angles of wood&mdash;such as trees, logs, or lumber&mdash;then determining warp potential of the wood based on the lengthwise shrinkage rates and grain angles. The method typically comprises measuring plural lengthwise shrinkage rates and plural grain angles to determine warp potential. Where the wood comprises lumber, lengthwise shrinkage rate and grain angle measurements typically are made on at least one major planar surface of the lumber at at least two measuring points separated by a predetermined distance, such as at substantially one-foot intervals along the lumber. Particular embodiments of the present invention determine lengthwise shrinkage rates using electromagnetic energy, acoustic energy, and combinations thereof. Working embodiments of the method use ultrasound energy to determine lengthwise shrinkage rates and grain angles. Another embodiment of the present invention comprises providing a piece of wood having at least one major planar surface, positioning the piece of wood adjacent to a device for imparting energy through the piece of wood to determine at least one lengthwise shrinkage rate and at least one grain angle. Embodiments of the present invention are automated and can be adapted to industrial processes for commercial production of lumber or for forest management practices. Warp potential can be determined using a finite element model (FEM).

Method for determining warp potential in wood

A method for determining twist potential of wood is described. One embodiment of the method comprises nondestructively obtaining a grain angle of wood, such as trees or lumber, and then determining twist potential of the wood based on the grain angle. Where the wood comprises lumber, grain angle determinations typically are made on at least one major surface of the lumber. The method typically comprises determining grain angle at at least two measuring locations separated by a predetermined distance, such as at substantially one-foot intervals along the board. The method also can further comprise obtaining at least one fiber dive angle. Particular embodiments of the present invention determine grain angle using infrared radiation, microwave radiation, light energy (such as by using a laser), electricity, ultrasound energy, and combinations thereof. Working embodiments of the method used light energy and ultrasound energy to determine grain angle. For example, a first transmission speed of an ultrasound pulse through the board was determined along a first path and along a second path. Grain angle was then determined by comparing the first and second transmission speeds. Plural grain angles also can be determined using this ultrasound method. Twist potential can be correlated to empirically determined twist angle. The method of the present invention provides can determine twist potential that correlates with empirically determined twist potential with an R,value of at least 0.50.

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Seattle, WA, United States of America

Mark A Stanish