Intelligent log sorting and variable-length LVL manufacturing

Abstract

According to an aspect, there is provided a method for log processing at a laminated veneer lumber, LVL, mill The method comprises the following. A plurality of logs having a plurality of different lengths are provided. The plurality of logs are cross-cut. The cross-cut logs comprise logs of a plurality of different lengths. The cross-cut logs are peeled using a peeler capable of processing logs of different lengths to produce a plurality of veneer sheets. The plurality of veneer sheets are cut to a pre-defined width. The pre-defined width is independent of a length of a veneer sheet. LVL boards are created from the plurality of veneer sheets.

Description

Intelligent log sorting and variable-length LVL manufacturingFIELD

[0001] Various example embodiments relate to sorting of logs for processing at a sawmill or a laminated veneer lumber (LVL) mill and / or processing of logs in the LVL mill.BACKGROUND

[0002] Log sorting is typically one of the first processes carried out for logs once they have been harvested and transported and loaded to a sawmill or other log sorting facility. The log sorting process may involve, for example, inspecting, measuring and grading the logs and sorting them into different categories or classes based on various criteria such as species, diameter, length, quality, and intended end use. Log sorting aims to optimize resource utilization, maximize product quality, and streamline production operations by directing each log to its most suitable processing pathway. Some of the logs may be processed at the sawmill where the sorting takes place while others may be transported to an LVL mill for processing. Conventionally, the logs transported to the LVL mill should be of a pre-defined length due to limitations of the LVL manufacturing.SUMMARY

[0003] According to some aspects, there is provided the subject-matter of the independent claims. Some example embodiments are defined in the dependent claims.

[0004] According to a further aspect, there is provided a method for log sorting by a log sorting system, comprising: receiving a log in the log sorting system; scanning, by an X-ray scanner of the log sorting system, the log; determining, by a computing device of the log sorting system or by the X-ray scanner, one or more candidate sawing patterns for the log based on results of the scanning; comparing, by the computing device, the determined one or more candidate sawing patterns against a plurality of pre-defined sawing patterns associated with arespective plurality of values of a sawing pattern utility metric to find one or more values of the sawing pattern utility metric for the one or more candidate sawing patterns; classifying, by the computing device, the log to one of a first category or a second category based on the one or more values of the sawing pattern utility metric, wherein the first category is defined for logs to be processed in a sawmill and the second category is defined for logs to be processed in a laminated veneer lumber, LVL, mill, the first category being defined for logs having higher sawing pattern utility compared to the second category; and sorting the log based on the classification by guiding it to one of one or more first trays corresponding to the first category or to one of one or more second trays corresponding to the second category.

[0005] The scope of protection sought for various example embodiments is set out by the independent claims. The example embodiments and features, if any, described in this specification that do not fall under the scope of the independent claims are to be interpreted as examples useful for understanding various example embodiments.BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Some example embodiments will now be described with reference to the accompanying drawings.

[0007] Figure 1 illustrates a system for performing log sorting in a sawmill according to embodiments;

[0008] Figure 2 illustrates a process for log sorting according to embodiments;

[0009] Figure 3 illustrates a process for variable-length LVL manufacturing according to embodiments;

[0010] Figures 4 & 5 illustrate, in a cross-sectional view, two exemplary 15-layer & 23-layer LVL boards produced using the method of Figure 3; and

[0011] Figure 6 illustrates an apparatus according to some embodiments.DETAILED DESCRIPTION

[0012] The following embodiments are only presented as examples. Although the specification may refer to “an”, “one”, or “some” embodiment(s) and / or example(s) in several locations of the text, this does not necessarily mean that each reference is made to the same embodiment(s) or example(s), or that a particular feature only applies to a single embodiment and / or example. Single features of different embodiments and / or examples may also be combined to provide other embodiments and / or examples.

[0013] As used herein, “at least one of the following: ” and “at least one of ” and similar wording, where the list of two or more elements are joined by “and” or “or”, mean at least any one of the elements, or at least any two or more of the elements, or at least all the elements.

[0014] As used herein, the term “lumber” refers to felled trees (i.e., raw or slightly processed wood material) while terms “timber” and “sawn timber” refer to sawn wood products (i.e., wood material which has been sawed and / or shaped to have a particular shape).

[0015] As described above, log sorting is typically one of the first processes carried out for logs once they have been harvested and transported and loaded to a sawmill or other log sorting facility. The log sorting process may involve, for example, inspecting, measuring and grading the logs and sorting them into different categories or classes based on various criteria such as species, diameter, length, quality, and intended end use. Log sorting aims to optimize resource utilization, maximize product quality, and streamline production operations by directing each log to its most suitable processing pathway. Some of the logs may be processed at the sawmill where the sorting takes place while others may be transported to another facility (e.g., an LVL mill) for processing.

[0016] Both saw mills and LVL mills typically have their own specific requirements for the log raw material, e.g., in terms of diameter, length and certain log quality criteria. A wood procurement entity harvests and delivers the logs according to the above requirements. However, after the delivery of the logs to the sawmill or LVL mill, the optimization possibilities are limited as each mill is, in any case, required to process all logs. The problem lies with the natural characteristic of wood being that wood is an inhomogeneous raw material. Thus, significant quality variation exists in saw logs, especially pine saw logs. To better monitor the quality of the processed logs, some modern sawmills employ an X-ray scanner for scanning the logs so as to determine internal properties of the logs. This enablesoptimization regarding selection of the most optimal sawing pattern (in terms of quality of the log) to be used for sawing the log. This does not solve, however, the problem that the lesser quality saw logs still have to be processed in the saw mill which reduces the total value generation. Moreover, each log diameter and log length is associated with dedicated sawing patterns (i.e., the sawing patterns are specific to log diameter and log length). In certain sawn timber market conditions, sawn timber products associated with some of these sawing patterns can face significant market price pressure and therefore can become less preferred (i.e., less in demand) leading to a situation, where these logs become less profitable or even unprofitable for the sawing business.

[0017] Moreover, as mentioned above, currently LVL mills have their own specific requirements for the log raw material also in terms of length. This is due to the fact that common LVL manufacturing lines are configured to process logs (and associated veneer sheets) of a single non-adjustable pre-defined length at a time. This arrangement has the benefit of making the process at the LVL mill simpler. If logs of multiple different lengths would be provided to such an LVL mill, said logs would need to be, first, sorted by length and, then, processed in multiple production batches corresponding to multiple log lengths. This is slow and inconvenient as well as an inefficient use of the LVL mill. Use of multiple different log / veneer lengths at LVL mill has also not been considered this far due to the fact that the saw mill and the LVL mill are typically operated as separate businesses and, thus, use of multiple different log / veneer lengths at LVL mill is impractical from a business point of view.

[0018] The embodiments to be discussed overcome or at least alleviate at least some of the problems described above.

[0019] Figure 1 illustrates a system for performing log sorting in a sawmill 102 according to some embodiments. Specifically, Figure 1 illustrates a forest 112 from which logs are harvested, a sawmill 102 comprising at least a log sorting system 105 and a sawing line 110 and an LVL mill 111. It should be appreciated that while it is assumed in Figure 1 that the log sorting takes place in the sawmill 102, in other embodiments, the log sorting may take place, e.g., in a dedicated facility not forming of a part of the sawmill or in an LVL mill. In some embodiments, the LVL mill 111 may form a part of the sawmill 102 or be arranged adjacent to it. In other embodiments, the LVL mill 111 may be a separate facility from the sawmill 102 and / or the log sorting facility.

[0020] As a first step of the lumber production process, the logs are harvested from a forest 112, e.g., using one or more harvesters. According to a general definition, a harvester is a forestry vehicle, which may be employed for felling and delimbing trees, and bucking or cutting the trees into logs. The harvested logs are transported from the harvesting site to the sawmill 102, e.g., using trucks equipped with loading cranes or trailers, or through the use of specialized logging equipment such as skidders or forwarders. The logs are unloaded to a designated lumber yard or loading area 101 of the sawmill 102.

[0021] It may be assumed that the harvested and unloaded logs contain logs of varying lengths and thicknesses and of varying quality and possibly also of varying species. Depending on these properties, a given log may be suitable for one or more different sawn timber products (e.g., different types of sawn dimension timber) and / or for one or more LVL products. To utilize the harvested logs in an optimal manner, the logs need to be sorted into different categories associated with different end uses for the logs. In embodiments, these categories comprise at least a first category defined for logs to be processed in the sawmill 102 and a second category defined for logs to be processed in an LVL mill 111. This sorting may be carried out in a fully or at least partially automated manner using elements 103 to 109 to be described below in detail.

[0022] It may be assumed, at least in some embodiments, that each of a plurality of different lengths of harvested and unloaded logs may be larger than 2 meters (or 3 meters) and / or smaller than 7 meters (or 6 meters). The plurality of different lengths may consist of a (pre-defined) set of log lengths. The plurality of different lengths may consist of a (predefined) set of standard log lengths (e.g., 4.3 m, 4.6 m, 4.9 m and 5.2 m or any subset thereof). Thus, during the harvesting, the felled tree trunk may be cut (or bucked) specifically into said set of standard log lengths.

[0023] Before the (automated) sorting is carried out, the harvest and unloaded logs may undergo an initial visual inspection to assess their overall condition and suitability for the subsequent processing. This inspection may comprise, for example, identifying any significant defects such as rot, decay, or excessive taper. Logs with sufficiently significant defects (e.g., defects which are so severe that the log cannot be utilized for any sawn timber or LVL products) may not be sorted.

[0024] The sorting of a log starts by placing the log onto a sorting line 103, e.g., manually or using a hydraulic loader or log manipulator. The sorting line 103 comprises atleast a conveyor system 104, a log sorting (computing) system 105 and sorting trays 106 to 109. The conveyor system 104 enables transporting or conveying a log from a first end of the sorting line 104 through the log sorting system 105 to a one of the sorting trays 106 to 109 (equally sorting bins) selected by the log sorting system 105 and arranged at an opposite end of the sorting line 104. As shown in Figure 1, the sorting trays 106 to 109 may be arranged on both sides of the conveyor system 104. The conveyor system 104 may comprise, for example, (conveyor) rollers, belts, or chains for moving logs along the sorting line 103 at a controlled speed.

[0025] In some embodiments, the sorting line 103 may further comprise a log deck preceding the conveyor system. The log deck serves to store the logs before they are fed to the conveyor system. The feeding of the logs from the log deck to the conveyor system may be performed in an automated manner using one or more sensors and a control system (comprising at least one control computing device) for monitoring log demand in the sorting line and adjusting log feed rates accordingly. This control system may be a dedicated control system of the sorting line or form a part of a control system of the log sorting system 105.

[0026] Logs are conveyed using the conveyor system 104 to the log sorting system 105. The log sorting system 105 is configured, in general, to analyze a log inserted into it and to make a sorting decision regarding said log based at least on said analysis. For enabling said analysis of the log, the log sorting system 105 comprises at least an X-ray scanner 121. The X-ray scanner 121 may be a three-dimensional (3D) (or equally 360°) X-ray scanner specifically configured for scanning logs. The X-ray scanner 121 may be configured to perform 360° X-ray computed tomography (CT) on the log so as to generate a full 3D model of the log depicting both its external shape and its internal structure (showing, e.g., any defects within the log). The X-ray scanner 121 may be, for example, a MiCROTEC CT Log 360° X-ray scanner.

[0027] In some embodiments, the X-ray scanner 121 may also be configured to determine one or more candidate sawing patterns for the log based on results of the X-ray scanning (e.g., the 3D model of the log). The one or more candidate sawing patterns may be sawing patterns which may be employed for sawing the scanned log so as to manufacture one or more sawn timber products associated with the sawing pattern considering properties (e.g., diameter and number, type and locations of defects) of the log as determined based on the results of the X-ray scanning. Each sawn timber product may be associated with certainquality requirements which have to be met. In other words, each sawn timber product may be associated with a certain quality class (matching said quality requirements).

[0028] In some embodiments, the log sorting system 105 may also comprise an optical 3D scanner for, e.g., determining length, diameter (i.e., width) and other external properties of the log (though said properties may be deducible also from the 3D volumetric model generated by the X-ray scanner).

[0029] The log sorting system 105 also comprises at least one control computing device 122 for receiving results of the X-ray scanning (e.g., a 3D model of the log) and / or one or more candidate sawing patterns determined based on said results from the X-ray scanner 121, making a sorting decision based on said results and / or one or more candidate sawing patterns and further on information stored in a memory of the control computing device or in an external database (e.g., a cloud database) to which the control computing device 122 is connected and triggering or causing the sorting of the log according to the sorting decision. Said stored information may relate, directly or indirectly, at least to a current demand, value and / or volume allocation of a plurality of different sawn timber products producible using different sawing patterns. Optionally, said information may also relate a quality of the different sawn timber products producible using different sawing patterns. In embodiments where the one or more candidate sawing patterns for the log are not received from the X-ray scanner 121, the control computing device 122 may determine the one or more candidate sawing patterns for the log based on results of the X-ray scanning (e.g., the 3D model of the log), instead of the X-ray scanner 121, and subsequently make the sorting decision based on the determined one or more candidate sawing patterns. As mentioned above, the logs may be sorted into one of two categories: a first category defined for logs to be processed in the sawmill 102 and a second category defined for logs to be processed in an LVL mill 111. The sorting functionality is described in further detail below in connection with Figure 2.

[0030] In the example of Figure 1, each log is sorted into one of the four sorting trays or bins 106 to 109. In this example, the trays 106, 107 are for logs belonging to the first category, that is, logs which are to be sawn at the sawmill 102 while the trays 106, 107 are for logs belonging to the second category, that is, logs which are to be processed at the LVL mill 111. Following the sorting, the logs in the trays 106, 107 may be transported to thesawing line 110 of the sawmill 102, and the logs in the trays 108, 109 may be transported to the LVL mill 111.

[0031] The sawing of a log in the sawing line 110 may be carried out using the sawing pattern which was deemed optimal for the log by the log sorting system 105. The sawing process may comprise, for example, the following steps: identification of the log (e.g., using a 3D laser, optical or X-ray scanner and a database storing log identifiers / fingerprints) and retrieval of the associated sawing pattern determined by the log sorting system 105, sawing of the log using the sawing pattern determined by the log sorting system 105, drying of the sawn timber products, sorting of the sawn timber products and packaging of the sawn timber products. The processing carried out at the LVL mill I l l is discussed below in connection with Figure 3.

[0032] In some embodiments, the sawmill 102 and the LVL mill 111 may be integrated into a single facility (i.e., a single mill). Thus, both the sawing line (of the sawmill) and the LVL line (of the LVL mill) may be located in close proximity of the log sorting line 103 so that the time required for transportation of the sorted logs is minimized.

[0033] Figure 2 illustrates a process of performing log sorting. The process of Figure 2 may be carried out using a (log) sorting line such as the sorting line 103 of Figure 1 or more specifically by an (automated) log sorting system of a sorting line such as the log sorting system 105 of Figure 1.

[0034] Referring to Figure 2, the log initially received in the log sorting system in block 201. For example, the log may be conveyed or transported into the log sorting system using a conveyor system, as described in connection with Figure 1. The log may be, for example, a log of pine, spruce or birch (i.e., a log of Pinus species such as Pinus sylvestris, a log of a Picea species such as Picea abies or a log of a Betula species). In some embodiments, the log may be, for example, a log of pine, spruce, fir, oak, maple, birch, cherry or walnut.

[0035] In some embodiments, the log may be a pine log. There is typically significant quality variance especially in (saw) logs of pine and, thus, the process of Figure 2 may be considered especially suitable for pine logs.

[0036] The log is scanned, in block 202, using an X-ray scanner (or a log X-ray scanner).

[0037] The X-ray scanner may be a three-dimensional (3D) (or equally 360°) (CT) X- ray scanner. Accordingly, the scanning may comprise capturing a plurality of X-ray images from a plurality of different angles around the log and optionally generating a 3D volumetric model (or equally a 3D volumetric reconstruction) of the log based on said plurality of X- ray images. The 3D volumetric model of the log is a digital representation of the internal structure and external surface of the log. The 3D volumetric model of the log may be representative of the quality of the log (showing, e.g., any possible defects within the log), that is, it may be called a quality pattern of the log.

[0038] One or more candidate sawing patterns for the log are determined, in block 203, based on results of the scanning (e.g., the 3D volumetric model). This determination may be carried out, e.g., by a control computing device of the log sorting system or by the X-ray scanner itself.

[0039] Each of the one or more candidate sawing pattern may define sawing for both the center piece and side boards of the log. Here and in the following, a center piece of a log refers to a central or core portion of the log. The center piece is typically cut from the middle of the log and may include the heartwood or pith (i.e., the innermost part of the tree trunk). This portion typically exhibits characteristics such as tighter grain patterns, fewer knots, and greater uniformity compared to the side boards of the log. The center piece is typically considered the highest quality portion of the log. Moreover, a side board of a log (equally called an edge board or a flitch) may be defined, here and in the following, to refer to the outer sections or portions of the log that lie farther away from the central core or pith compared to the center piece. These sections are cut from the sides of the log, adjacent to the center piece. Side boards may contain the sapwood, or outer layer of the tree trunk, as well as the cambium layer and bark. Depending on the sawing pattern side boards may vary in width and thickness. Compared to the centerpiece, sideboards are often (but not always) used for lower-grade sawn timber products, such as construction timber, fencing, pallets, and industrial applications. Certain high quality sideboards (being, e.g., free of defects such as knots) may be used for higher-grade sawn timber products. Such high quality sideboards may be obtained, for example, from some butt logs (e.g., of pine). In general, the quality of the wood in the sideboards of logs may vary considerably.

[0040] The determination of the one or more candidate sawing patterns for the log in block 203 may be based at least one on a diameter (i.e., a width) and a quality of the log asdetermined from the results of the scanning of block 202 (e.g., based on the plurality of X- ray images or the 3D volumetric model of the log generated based thereon) and pre-defined diameter (i.e., width) and quality requirements of different sawing patterns (or sawn timber products associated the different sawing patterns). In some embodiments, the determination of block 203 may be further based on a length of the log and pre-defined length requirements of different sawing patterns (or sawn timber products associated the different sawing patterns). In other words, each combination of a log diameter and a log length may have its own specific sawing pattern(s) which may, each, be associated with certain quality requirements. As mentioned above, in some embodiments, the diameter and / or length of the log may be determined, alternatively, based on results of a 3D optical or laser scanning of the log.

[0041] The quality of the log may depend on a plurality of different factors derivable based on the results of the scanning of block 202 (e.g., based on the plurality of X-ray images or the 3D volumetric model of the log generated based thereon). For example, the quality of the log may be determined based on one or more of the following: straightness of the log, uniformity of the log, moisture content of the log, soundness of the log, grain orientation (or slope of grain) of the log, a ratio of heartwood to sapwood in the log, amount of pith in the log, number of defects in the log, locations of the defects in the log or types of the defects in the log. In some embodiments, at least number of defects in the log, locations of the defects in the log and / or types of the defects in the log may be taken into account in the evaluating the quality of the log. Different types of defects which may be considered when evaluating the quality of the log may comprise, for example, one or more of (heavy) rot, resin pockets, knots, checks, splits, embedded stones, bark inclusions, shakes, wane, reaction wood (also known as compression wood), insect damage or mineral stains. In some embodiments, at least resin pockets and / or knots may be taken into account in the evaluating the quality of the log. Knots may be further classified into sound knots, dead knots, loose knots, decayed knots, encased knots, spike knots, pin knots, face knots, through knots, intergrown knots, wane knots or cluster knots. The quality requirements of different sawing patterns may take into account any of the factors discussed in this paragraph.

[0042] In some embodiments, the one or more candidate sawing patterns comprise or consist of:1) all sawing patterns suitable for sawing the log based on the results of the scanning (e.g., the plurality of X-ray images or the 3D volumetric model of the log generated based thereon); or2) a pre-defined number of sawing patterns most suitable for sawing the log based on the results of the scanning (e.g., the plurality of X-ray images or the 3D volumetric model of the log generated based thereon), wherein the pre-defined number is equal to or larger than one.Thus, in option 1, all sawing patterns for which the log satisfies the pre-defined width, quality (and length) requirements may be selected as candidates while, in option 2, a pre-defined number of sawing patterns for which the log satisfies the pre-defined width, quality (and length) requirements may be selected as candidates. In option 2, the sawing patterns associated with higher quality sawn timber products (i.e., with higher quality requirements) may be preferred over sawing patterns associated with lower quality sawn timber products (i.e., with lower quality requirements). Moreover, in option 2, if there are not enough suitable sawing patterns for the log, smaller than the pre-defined number of sawing patterns may be selected as candidates.

[0043] The determined one or more candidate sawing patterns are compared, in block 204, against a plurality of pre-defined sawing patterns associated with a respective plurality of values of a sawing pattern utility metric to determine one or more values of the sawing pattern utility metric for the one or more candidate sawing patterns. The comparing in block 204 may be performed by the control computing device of the log sorting system. The sawing pattern utility metric may be defined to be a metric indicative of current utility or usefulness of a particular sawing pattern. Thus, the value of the sawing pattern utility metric may be dynamically changing over time. The sawing pattern utility metric may be dependent at least on current (combined) demand for and / or value (e.g., monetary value) of one or more different sawn timber products prepared by using an associated sawing pattern in the sawmill. Additionally or alternatively, the sawing pattern utility metric may be dependent on quality associated with the one or more different sawn timber products prepared by using the associated sawing pattern in the sawmill. Here, the quality may be evaluated based on the quality requirements (or quality class or classes) associated with a given candidate sawing pattern (it is assumed here that these quality requirements are met based on the determination in block 203). High demand and high quality (i.e., high quality requirements for the sawn timber products) may be associated with a higher value of the sawing pattern utility metric. Additionally or alternatively, the sawing pattern utility metric of a sawingpattern may depend, e.g., on current volume allocation (or production share) of one or more different sawn timber products prepared by using the sawing pattern. The current volume allocation of a sawn timber product may be defined, e.g., based on expected sales of the sawn timber product. The current price of the one or more different sawn timber products prepared by using the sawing pattern is typically dependent on quality requirements for the one or more sawn timber products and market demand for the one or more sawn timber products. The current volume allocation may be considered indicative of demand for the sawn timber product.

[0044] The plurality of values of the sawing pattern utility metric may be stored in a memory of the control computing device or in an external database (e.g., a cloud database), that is, they may be pre-defined. Alternatively, the control computing device may calculate each of the plurality of values of the sawing pattern utility metric dynamically, during the comparing, based, e.g., on at least one of a current demand, a current value (e.g., monetary value), current volume allocation or quality of one or more sawn timber products associated with that sawing pattern stored, e.g., in an external database (e.g., a cloud database).

[0045] The log is classified, in block 205, to one of a first category or a second category based on the one or more values of the sawing pattern utility metric. As described above, the first category is defined for logs to be processed in a sawmill and the second category is defined for logs to be processed in a laminated veneer lumber, LVL, mill. The first category is defined for logs having higher sawing pattern utility (e.g., which are currently more in demand and / or more valued) compared to the second category. Higher sawing pattern utility means here higher values of the sawing pattern utility metric. The classifying may be performed by the control computing device of the log sorting system.

[0046] In some embodiments, the classifying of block 205 may comprise: in response to the highest of the one or more values of the sawing pattern utility metric satisfying one or more pre-defined criteria for high sawing pattern utility, classifying the log to the first category; and in response to the highest of the one or more values of the sawing pattern utility metric failing to satisfy the one or more pre-defined criteria for high sawing pattern utility, classifying the log to the second category. Here, the highest of the one or more values of the sawing pattern utility metric may be associated with a candidate sawing pattern considered as the most beneficial alternative for the sawing pattern for the log under analysis.

[0047] In some embodiments, the one or more pre-defined criteria may comprise a pre-defined threshold for the sawing pattern utility metric. Here, high sawing pattern utility corresponds to a value of the sawing pattern utility metric exceeding the pre-defined threshold, and low sawing pattern utility corresponds to a value of the sawing pattern utility metric being equal to or falling below the pre-defined threshold.

[0048] Finally, the log is sorted, in block 206, based on the classification (i.e., based on the selected one of the first or second category) by guiding (or conveying) it to one of one or more first trays or bins corresponding to the first category or to one of one or more second trays or bins corresponding to the second category. The guiding (or conveying) may be carried out using the conveyor system of the log sorting system under control of the control computing device of the log sorting system.

[0049] In some embodiments, the following additional steps may be carried out (e.g., by the control computing device or the X-ray scanner of the log sorting system) when the log is classified to the first category. Firstly, a candidate sawing pattern of the one or more candidate patterns having the highest value of the sawing pattern utility metric may be selected as a sawing pattern of the log. Then, the results of the scanning (e.g., the 3D volumetric model of the log) and / or a log identifier (or a log fingerprint or, more generally, log identification information) calculated based on the results of the scanning and / or the sawing pattern for the log may be stored to an external database accessible by a laser, optical or X-ray scanner of the sawmill for enabling identification of the log and determining of the sawing pattern of the log at the sawmill. The log identifier or fingerprint contains information on identifying properties of the log (e.g., location, shape and / or type of knots) in a compressed format.

[0050] In some embodiments, a third category for the classification of the logs may be defined in block 205. Namely, said third category may correspond to logs which are determined to comprise a first log section suitable for processing at the sawmill (i.e., belonging to the first category) and a second log section suitable for processing at the LVL mill (i.e., belonging to the second category). The determination that a log belongs to said third category may be based on results of the scanning (e.g., the 3D volumetric model) obtained in block 202. For example, a log may be classified to the third category if the log has a (significant) defect affecting only a part of the log. Such a defect may be, for example, a bend (e.g., a crook or a kink) of the log, curving of a section of the log exceeding a pre-defined allowed limit for curving or tapering of a section of the log exceeding a pre-defined allowed limit for tapering of the log. Such logs may be cross-cut following the classification and the first and second log sections may be transported to the sawmill and the LVL mill, respectively.

[0051] Figure 3 illustrates a process of creating LVL boards from a plurality of logs having a plurality of different lengths. The plurality of logs may be, for example, logs which were previously sorted (e.g., at the sawmill) to the second category (i.e., the category for lower grade logs) using the sorting process of Figure 2. The process of Figure 3 may be carried out in an LVL mill to which the sorted logs may have been transported (e.g., using trucks equipped with loading cranes or trailers).

[0052] Referring to Figure 3, it is initially assumed that there is provided a plurality of logs having a plurality of different lengths (e.g., 2, 3 or 4 different lengths). For example, each of the plurality of different lengths may be larger than 2 meters (or 3 meters) and / or smaller than 7 meters (or 6 meters). The plurality of different lengths may consist of a (predefined) set of log lengths. The plurality of different lengths may consist of a (pre-defined) set of standard log lengths (e.g., 4.3 m, 4.6 m, 4.9 m and 5.2 m or any subset thereof). The plurality of logs may also have a plurality of different widths. The plurality of logs may be, for example, logs which have been sorted to the second category using the process of Figure 2 and, subsequently, transported (e.g., using one or more trucks) or conveyed (e.g., if the log sorting system and the LVL mill are co-located) to the LVL mill. The plurality of logs may be conveyed between the different processing stages of the illustrated process (i.e., debarking, soaking, cross-cutting, peeling, stacking and cutting) using a conveyor system.

[0053] In some embodiments, the plurality of logs may comprise, for example, one or more logs of pine, one or more logs of spruce and / or one or more logs of birch (i.e., of a Pinus species such as Pinus sylvestris, a log of a Picea species such as Picea abies or a log of Betula species). In some embodiments, the plurality of logs may comprise, for example, a log of pine, spruce, fir, oak, maple, birch, cherry or walnut. In some embodiments, the plurality of logs comprise one or more pine logs or a plurality of pine logs.

[0054] As initial steps, the plurality of logs are debarked, soaked and cross-cut in block 301. The resulting logs (i.e., cut log sections) may comprise logs of a plurality of different lengths (e.g., 2, 3 or 4 different lengths). The debarking, soaking and cross-cutting steps may be carried out in the listed order or in some other order. For example, in someembodiments, both the debarking and the cross-cutting may precede the soaking (or steaming), that is, block 301 may comprise debarking, cross-cutting and soaking the plurality of logs (in this order). The debarking, soaking and cross-cutting in block 301 may be carried out, at least in some embodiments, using conventional debarking, soaking and cross-cutting methods employed in an LVL mill. The logs may be conveyed between the different processing stages (i.e., between debarking, soaking and cross-cutting) and to the following peeling stage using the conveyor system.

[0055] The debarking in block 301 may be carried out, for example, using a debarking machine. The debarking machine is configured to remove the bark from the surface of a log using rotating blades or some other abrasive mechanism.

[0056] The soaking in block 301 serves to soften the wood of the logs and, thus, make it more pliable for facilitating subsequent peeling. The soaking ensures high veneer quality with good surface properties. The soaking may comprise, for example, submerging the debarked logs into a (warm or hot) water bath (equally called a log soaking bath or pool or a log conditioning bath or pool). The temperature of the water used in the soaking may be, e.g., between 30°C and 80°C. In some embodiments, steaming may be employed instead of soaking.

[0057] In the cross-cutting process of block 301, the debarked and soaked logs are cut into smaller sections or segments (sometimes called billets or blocks). The cross-cutting may be performed using one or more cross-cutting devices comprising, e.g., one or more (crosscut) saws. As mentioned above, at least some of the cut log sections formed from the plurality of (debarked and soaked) logs are of different length. Namely, the cross-cutting (i.e., the one or more cross-cutting devices) may employ a plurality of pre-defined cutting lengths. For example, each of a plurality of cross-cutting devices may employ, respectively, a plurality of pre-defined cutting lengths (e.g., 2, 3 or 4 cross-cutting devices using, altogether, 2, 3 or 4 pre-defined cutting lengths). Alternatively, at least one tunable cross-cutting device may be employed for implementing the plurality of pre-defined cutting lengths.

[0058] In the cross-cutting of block 301, one of the plurality of pre-defined cutting lengths may be selected, for each log, for use in cutting the log. Said selection may be done based on the length of the log (which, as mentioned above, may conform to one of a predefined set of lengths). Namely, said one of the plurality of first pre-defined cutting lengths may be selected so as to maximize the total length of the one or more cut sections (i.e., tominimize the length of the leftover section having an arbitrary length). The kerf loss may also be taken into account in said selection. The kerf loss is defined as the material loss during a cutting process. In practice, cutting of the log using a selected pre-defined cutting length may mean that the log is conveyed to one of the plurality of cross-cutting devices using the selected pre-defined cutting length or that the cutting length of a tunable crosscutting device is tuned to use the selected pre-defined cutting length. For each of the plurality of logs, the cross-cut sections formed from the log may comprise one or more sections of a selected pre-defined length (matching the selected pre-defined cutting length) and possibly a single (leftover) section not matching any of said plurality of first pre-defined cutting lengths. The leftover section may be discarded.

[0059] In some embodiments, the plurality of logs may comprise a plurality of lengths each of which is divisible, after accounting for the kerf loss, by at least one of the pre-defined cutting lengths so that no leftover sections are formed in the cross-cutting. For example, if the plurality of logs to be cross-cut comprise logs of lengths 4.3 m, 4.6 m, 4.9 m and 5.3 m, the cut log sections may have, respectively, lengths 2.10 m, 2.25 m, 2.40 m and 2.55 m.

[0060] In other embodiments, for each log, one or more of the plurality of cutting lengths may be selected for use in cutting the log. In other words, instead of cutting a given log using one of the plurality of pre-defined cutting lengths, the log may be cut using multiple pre-defined cutting lengths so as to form log segments of a plurality of different lengths. Also here, said one or more of the plurality of first pre-defined cutting lengths may be selected so as to maximize the total length of the one or more cut sections (i.e., to minimize the length of the leftover section having an arbitrary length). This may be implemented using a tunable cross-cutting device. The features described in the previous paragraph may apply, mutatis mutandis, also here.

[0061] In some embodiments, the debarking and / or soaking steps of block 301 may be considered optional. In other words, the plurality of logs may be cross-cut without first debarking them and / or without soaking them before or after the cross-cutting.

[0062] The cross-cut logs (i.e., billets or log sections) are peeled, in block 302, using a peeler (or a peeling machine or a peeling line) capable of processing logs (i.e., billets or log sections) of different lengths to produce a plurality of veneer sheets. Each produced veneer sheet may have a thickness of 6 mm or less. To enable the processing of logs ofdifferent lengths, the peeler (or the peeling machine or the peeling line) may be spindless (i.e., spindleless) or a peeler comprising an adjustable spindle.

[0063] According to a general definition, a spindle of a peeler is a (typically cylindrical) rotating component that holds and rotates the log during the peeling process. During the peeling, the log is mounted on the spindle, which is typically driven by a motor to rotate at high speed. As the log rotates, a cutting tool mounted on the peeler removes thin layers of veneer from the surface of the log, producing continuous sheets of veneer. The spindle has the purpose of securely holding the log in place and providing the rotational motion necessary for the peeling operation. The adjustable spindle is a spindle which is adjustable (along a length direction which is parallel to the mounted log) so as to enable mounting of logs of different lengths onto it. These spindle adjustments to account for a length of a (present) log to be peeled may be manual, semi-manual (i.e., adjustment of the spindle position is set and initiated by a human operator but the adjustment itself is automated) or (fully) automated (e.g., using, e.g., a servo-controlled spindle positioning system and an automatic length detection system comprising one or more sensors and / or log scanners for determining the length of the log).

[0064] Unlike traditional peelers that utilize spindles to hold and rotate logs during the peeling process as described above, a spindless peeler operates without the use of spindles. Instead of spindles, a spindless peeler typically employs advanced gripping mechanism(s) or chucking system(s) (comprising, e.g., chuck or drive rollers) to securely hold and rotate logs during peeling. These systems may comprise, for example, hydraulic or pneumatic clamps, rollers, and / or belts that grip the logs and rotate them while a cutting tool removes thin layers of veneer from the log surface.

[0065] In some embodiments, the plurality of different lengths of the plurality of log sections (formed by the cross-cutting in block 301) are within the range of 1250 mm - 3000 mm (or 1500 mm - 3000 mm). Accordingly, the peeler used in block 303 may be configured to process logs (or billets or log sections) having a length within the range of 1250 mm - 3000 mm (or 1500 mm - 3000 mm).

[0066] The plurality of veneer sheets are cut, in block 303, to a pre-defined width. Here, the pre-defined width is independent of a length of a veneer sheet (which matches the length of the corresponding log section). The cutting in block 303 may be carried out, e.g., using a veneer trimming saw. The following veneer conveyor system(s) and the lay-up (i.e.,stacking) and press lines may be specifically designed to accommodate a plurality of different veneer lengths but only said single pre-defined width.

[0067] In some embodiments, the peeling and cutting stages of blocks 302, 303 may be followed by one or more of the following stages (not shown in Figure 3): drying the plurality of veneer sheets (e.g., using a combination of heat and airflow in a controlled environment); and / or sorting the plurality of veneer sheets (e.g., by length, thickness, grain pattern, and / or visual defects).

[0068] LVL boards are created, in block 304, from the plurality of cut veneer sheets. An LVL board may be equally called an LVL plank. Each created LVL board may comprise five or more veneer sheet layers.

[0069] At least in some embodiments, the creating of the LVL boards in block 304, may comprise (optionally, as a first stage) a scarfing stage where the plurality of veneer sheets are scarfed. In scarfing, the ends of the plurality of veneer sheets are cut (or machined) at an angle (known as a scarf joint or a plain scarf joint) to allow for longitudinal joining of shorter veneer sheets into longer ones. In other words, in scarfing, two ends of veneer sheets are cut at matching angles so that they may be joined end-to-end (with a large contact surface). Said angle may be, for example, between 5 and 12 degrees. The scarfing may be carried out for two opposite sides of the veneer sheet for, respectively, the two opposite ends of the veneer sheet. Scarfing enables creation continuous lengths of LVL by bonding the veneer sheets at their angled edges which serves to improve the strength and integrity of the formed joint.

[0070] The scarfing may be performed by at least one scarfing machine (sometimes called a scarfing saw). The plurality of veneer sheets may be automatically conveyed to and from the at least one scarfing machine using at least one scarfing line (i.e., a scarfing conveyor system). In some embodiments, the at least one scarfing machine may comprise a tunable scarfing machine for scarfing veneer sheets of different lengths. In other embodiments, a separate scarfing machine may be provided for each different length of veneer sheets. Use of multiple scarfing machine configured, each, to scarf veneer sheet of a particular length may be beneficial, e.g., in embodiments where multiple lengths of veneersheets are used in a single production batch (i.e., where produced LVL boards comprise veneer sheet of multiple different lengths).

[0071] To enable scarfing of the plurality of veneer sheet having a plurality of different lengths, a plurality of scarfing machines may be employed where each scarfing machine is configured to perform scarfing for veneer sheets of a particular length (i.e., the plurality of scarfing machines are configured to perform scarfing for veneer sheet of a respective plurality of lengths). The plurality of scarfing machines may comprise, for example, 2 or 3 scarfing machines for scarfing veneer sheets of 2 or 3 different lengths. This alternative provides the benefit that scarfing may be performed while the veneer sheets are being conveyed along the scarfing line (or specifically along a plurality of scarfing lines corresponding, respectively, to the plurality of scarfing machines) without slowing down the LVL manufacturing process (e.g., a lay-up stage to be discussed below may be run continuously without interruptions caused by scarfing). Alternatively, a single scarfing machine may be employed so that the configuration of the scarfing machine is adjusted each time the length of the veneer sheet to be processed changes to enable scarfing of veneer sheets of a plurality of different lengths.

[0072] The creation of each of the LVL boards in block 304 may further comprise the following steps. Multiple veneer sheets of the same length and width (i.e., said pre-defined width) or at least of the same width are stacked (i.e., laid up) on top of each other to form a veneer lay-up (or a veneer lay-up stack). Each veneer layer may comprise multiple veneer sheets joined at the seams or (scarf) joints. The lay-up may be carried out according to a specific lay-up sequence. An adhesive (e.g., a heat-cured resin) is applied between the veneer sheets before and / or during this stacking process so as to form a solid composite structure. The adhesive may be applied to each individual veneer sheet or sprayed onto the entire LVL board. The adhesive may be applied, for example, using a liquid extruder gluing process, where the liquid or semi-liquid adhesive is extruded from at least one extruder (e.g., a plurality of extruders spanning the width of the veneer sheet) onto the veneer sheet in a controlled manner. Typically, a uniform distribution of the adhesive across the surface of the veneer sheet is targeted. Alternatively, the adhesive may be applied, for example, using curtain coating. In curtain coating, an uninterrupted curtain of liquid or semi-liquid adhesive is released (or dropped) from a holding container via a coating head, slit or a die of the holding container. In order to coat the veneer sheet, the veneer sheet is conveyed through said curtain at a regulated speed (e.g., using a conveyor belt or calender rolls). Alternatively,the adhesive may be applied using at least one adhesive spreader (e.g., at least one roller spreader, at least one brush spreader or at least one air-pressurized spreader). The stacking and the applying of the adhesive (or at least the stacking) may be carried out on a lay-up line (comprising, e.g., a lay-up table, one or more glue spreaders and one or more layering conveyors) which may be connected to the at least one scarfing line. The cut veneer sheets may be conveyed to the lay-up table via one or more veneer feeding stations. The cut veneer sheets may be directed to lay-up with grain direction length-wise. Then, the veneer lay-up is pressed, using at least one press comprising, e.g., a hydraulic or mechanic (hot) press, to form an LVL board. The pressing serves both to apply heat and pressure onto the layers of the veneer lay-up to compress them together and to cure the adhesive.

[0073] In some embodiments, the pressing may comprise separate pre-pressing and hot pressing phases. Thus, the creation of each of the LVL boards in block 304 may, e.g., comprise scarfing the veneer sheets, applying an adhesive on cut and scarfed veneer sheets to be included in the LVL board, performing lay-up for the cut veneer sheets (i.e., stacking the cut veneer sheet), pre-pressing the formed lay-up and hot pressing the formed lay-up (in this order). In the pre-pressing step carried out using a pre-press, (light) pressure is applied to the lay-up to flatten and lightly bond the veneer sheets of the lay-up. This serves to prepare the lay-up for the hot pressing. In the hot pressing step, both high pressure (that is, higher than in the pre-pressing phase) and hot temperature is applied to the lay-up to bond the veneer sheets of the lay-up tightly together. Here, the high temperature serves to cure the adhesive. The LVL board gains its full structural strength during the hot pressing, with the adhesive forming a permanent, durable bond between the veneer sheets.

[0074] In some embodiments, the plurality of veneer sheets may be arranged in the LVL boards so that grain runs parallel to a length of the LVL board for giving the LVL boards high strength and stiffness along the grain.

[0075] For the creation of the LVL boards (or specifically for the lay-up and pressing phases thereof) in block 304, one of two different options may be employed. In the first option, only veneer sheets of having the same single length and width are used in each production batch. In other words, veneer sheets having the same length and the same predefined width may be used for forming one or more LVL boards having the same length in block 304. The seams or (scarf) joints across the veneer layers may be staggered (i.e., non- aligned) for improving structural strength, stability, and integrity of the LVL board. In otherwords, the seams or (scarf) joints in one veneer layer are offset relative to those in adjacent veneer layer(s). The distance between adjacent seams or (scarf) joints in two adjacent veneer layers of the LVL board (measured along a plane of the LVL board), i.e., said offset, may be constant (or uniform) across the LVL board (i.e., constant or uniform staggering is employed). This process may, then, be repeated for one or more further lengths of veneer sheets. This is a rather simple option which is easy to manage though it requires a larger veneer inventory.

[0076] In some embodiments based on said first option, at least one LVL board manufactured between a first production batch associated with a first length of veneer sheets and a second production batch associated with a second veneer of veneer sheets (different from the first length) may comprise veneer sheets of both the first and second lengths. For example, each veneer layer of the at least one LVL board may comprise veneer sheets of the first and second lengths. The (relative) arrangement or pattern of the veneer sheets of the first and second different lengths within a given veneer layer may be the same in all veneer layers (though, as mentioned above, the seams or (scarf) joints may be staggered). For example, the first and second lengths of veneer sheets may be alternated in the same manner in all veneer layers. Any other LVL board structure discussed in connection with the second option to be discussed below may also be used for the at least one LVL board discussed in this paragraph.

[0077] In the second option, different veneer lengths but the same width are used in the same production batch. In other words, veneer sheets having multiple different lengths and the same pre-defined width may be used for forming one or more LVL boards in block 304. Here, each layer of the LVL board may comprise veneer sheets of one or more different lengths. In some embodiments, each layer (or at least some layers) of the LVL board may comprise veneer sheets of a plurality of different lengths (see examples of Figures 4 & 5). In this second option, the seams or (scarf) joints across the veneer layers may also be staggered. However, in this case, the distance between adjacent seams or (scarf) joints in two adjacent veneer layers of the LVL board (measured along a plane of the LVL board) may be either constant (or uniform) or non-constant (or non-uniform), that is, it may vary across the LVL board (namely, along the thickness of the LVL board). In other words, the staggering may be uniform or non-uniform across the LVL board.

[0078] In case of constant staggering of seams or (scarf) joints, each veneer layer of the LVL board may comprise veneer sheets of the same plurality of different lengths (e.g., 2, 3 or 4 different lengths). The (relative) arrangement or pattern of the veneer sheets of the plurality of different lengths within a given veneer layer may be the same in all veneer layers (though, as mentioned above, the seams or (scarf) joints may be staggered). For example, the different lengths of veneer sheets may be alternated in the same manner in all veneer layers.

[0079] In case of non-constant (or non-uniform) staggering of seams or (scarf) joints, the structure of the LVL product (i.e., the created LVL board) may be designed so that the variation in the distances between adjacent seams or (scarf) joints (i.e., variation in the staggering offset) is minimized (i.e., made as small as possible considering the different lengths of the veneer sheets to be used in the different layers of the LVL board). In other words, the veneer sheets of the plurality of different lengths may be arranged into layers of the LVL board (or equally veneer lay-up) so as to (substantially) minimize variation in the staggering across the veneer lay-up. Thus, the staggering may not be exactly constant (or uniform) but, at least in some embodiments, substantially constant (or uniform). Substantially constant staggering may mean here that the distance between adjacent seams or (scarf) joints in two adjacent veneer layers of the LVL board (measured along a plane of the LVL board) is within a pre-defined range for all adjacent seam or (scarf) joints. In some embodiments, said non-constant staggering may have a periodic pattern.

[0080] In some embodiments, when using multiple different veneer lengths, it may be required that, for all layers of the veneer lay-up (or equally of the LVL board), the total number of veneer sheets per layer is equal and a sum of different lengths of veneer sheets used in a given layer weighted by respective weighing factors is equal to the same constant value. Here, the weighing factor for a particular veneer sheet length used in a particular layer is defined to be directly proportional to (e.g., equal to) a ratio between the number of veneer sheets of said length in the layer and the total number of veneer sheets in the layer. For example, if a layer comprises an equal number of veneer sheets of each different length, all weighing factors for that layer may be equal to the same constant value (e.g., one), as will be discussed in further detail in connection with Figure 5.

[0081] Considering a continuous LVL production process, the second option may require a larger number of veneer feeding stations to the lay-up line as each different veneerlength may require a separate veneer feeding station and separate set of veneer-length- specific veneer feeding stations may be required at least for the top veneer layer, for the bottom veneer layer and for the set of middle veneer layers. In some cases, the set of middle veneer layers may be divided into two different veneer layer categories requiring a separate set of veneer-length-specific veneer feeding stations. On the other hand, the second option does enable more efficient use of veneer sheets of different lengths.

[0082] In some embodiments corresponding to the second option, the stacking of the veneer sheets may comprise forming each layer of the veneer lay-up from veneer sheets of two or more different lengths (e.g., 2, 3, 4 or 5 different lengths) so that different lengths of veneer sheets are alternated within the layer. In other words, the same lengths of veneer sheets may be used in all layers. The different lengths of veneer sheets may be alternated within the layer according to a pre-defined alternating pattern. The pre-defined alternating pattern may be a periodic pattern. Each of the different lengths may or may not occur at equal frequency in the pre-defined alternating pattern. For example, if the plurality of different lengths consist of first and second lengths, every other veneer sheet in a given layer has the first length and every other the second length. In other embodiments, a more complicated alternating pattern may be employed. Thus, the term “pre-defined alternating pattern” may encompass both alternating in a simple linear periodic fashion (e.g., length 1, length 2, length 3, length 1, length 2, length 3,...) and alternating according to a more complex periodic or even non-periodic fashion (e.g., length 1, length 2, length 1, length 3, length 1, length 2, length 1, length 3,. . .). The distance between adjacent scarf joints in two adjacent veneer layers of the veneer lay-up may be constant (or uniform) across the veneer lay-up. An example of this type of LVL board is shown in FIG. 4.

[0083] In some embodiments corresponding to the second option, the stacking of the veneer sheets may comprise forming every odd-numbered layer of the veneer lay-up from veneer sheets of two or more first lengths (being different lengths) so that the two or more first lengths of veneer sheets are alternated within the (odd-numbered) layer and forming every even-numbered layer of the veneer lay-up from veneer sheets of two or more second lengths (being different lengths) so that the two or more second lengths of veneer sheets are alternated within the (even-numbered) layer. In some embodiments, the number of the two or more first lengths and the number of the two or more second lengths may be equal (e.g., 2, 3 or 4). The two or more first lengths of veneer sheets may be alternated within the odd- numbered layer according to a first pre-defined alternating pattern, and the two or moresecond lengths of veneer sheets may be alternated within the even-numbered layer according to a second pre-defined alternating pattern. The first and second pre-defined alternating patterns may be defined similar to the pre-defined alternating pattern discussed above. The first and second pre-defined alternating patterns may be periodic patterns. Each of the first / second different lengths may or may not occur at equal frequency in the first / second pre-defined alternating pattern. The layers may be counted here either starting from the bottom or top layer of the veneer lay-up (i.e., either the bottom layer or the top layer may be the layer 1). The two or more second lengths may be, fully or at least partially, different from the two or more first lengths. The two or more first lengths and the two or more second lengths may be defined so that the sum of the two or more first lengths is equal to a sum of the two or more second lengths, assuming that the two or more first lengths occur an equal number of times (e.g., once or twice), per period, in the first pre-defined periodic alternating pattern, and the two or more second lengths occur said (same) equal number of times (e.g., once or twice), per period, in the second pre-defined periodic alternating pattern and, optionally, the number of the two or more first lengths and the number of the two or more second lengths are equal. In other words, the periods of the first and second pre-defined periodic alternating patterns (in length) may be equal. This serves to minimize the variation in distances between adjacent scarf joints in two adjacent veneer layers of the veneer lay-up (i.e., variation in the staggering across the veneer lay-up). The variation in the staggering offset follows, here, a pre-defined repeating pattern. An example of this type of LVL board is shown in FIG. 5.

[0084] In either of the first and second options, the distance(s) between adjacent (i.e., closest) seams or (scarf) joints in two adjacent veneer layers of the veneer lay-up may be at least larger than or equal to 100 mm (measured along the plane of the veneers). This distance corresponds to the extent of staggering of the seams or (scarf) joints of the LVL board. Additionally or alternatively, the distance(s) between adjacent (i.e., closest) seams or (scarf) joints in two adjacent veneer layers of the veneer lay-up (measured along the plane of the veneers) may be larger than or equal to 6 veneer thicknesses. Additionally or alternatively, the distance(s) between adjacent (i.e., closest) seams or (scarf) joints in a given single veneer layer may be equal to or larger than 30 times the veneer thickness. The distances discussed here may be calculated from closest points of the associated seams or (scarf) joints (i.e., not from the center of the seams or scarf points).

[0085] Following the creation of the LVL boards in block 304, the created LVL boards may still optionally be sawed to implement desired width and / or length (e.g., for a given LVL product) and / or packaged in the LVL mill (not shown in Figure 3).

[0086] In some embodiments, some of the veneer sheets may be flipped (or turned) during the LVL production process and added to the veneer lay-up in said flipped orientation to improve homogeneity of the manufactured LVL board. Separate feeding stations to the lay-up line may be required for flipped and non-flipped veneers of a given length. Namely, the set of middle veneer layers in the lay-up may comprise both flipped and non-flipped veneer sheets of multiple different length.

[0087] The blocks, related functions, and information exchanges described above by means of Figures 2 and 3 are in no absolute chronological order, and some of them may be performed simultaneously or in an order differing from the given one. Other functions can also be executed between them or within them, and other information may be sent, and / or other rules applied. Some of the blocks or part of the blocks or one or more pieces of information can also be left out or replaced by a corresponding block or part of the block or one or more pieces of information.

[0088] Figures 4 & 5 illustrate two exemplary 15-layer & 23-layer LVL boards produced using the method of Figure 3 in a cross-sectional view. Figures 4 & 5 are simplified schematic drawings where seams or (scarf) j oints are depicted simply as vertical lines. In a more realistic depiction, said vertical lines should be replaced with diagonal lines corresponding to the scarfing angle. Specifically, Figures 4 & 5 illustrate examples of the second option for forming LVL boards from veneer sheets of multiple different lengths, where multiple different lengths are used in a single production batch, as discussed in connection with Figure 3. In Figures 4 & 5, the grain direction of the veneer sheets corresponds to the horizontal direction.

[0089] The LVL board of Figure 4 consists of veneer sheets of two different lengths h and h. In each layer of the LVL board, every other veneer sheet has the length h and every other the length h, that is, lengths h and h are alternated in each layer of the LVL board (in a linear manner). The seams or (scarf) joints across the veneer layers are staggered. Namely, the distance d between adjacent seams or (scarf) joints in two adjacent veneer layers of the LVL board is constant (or uniform) across the LVL board. Said staggering provides the benefit of improving the structural strength, stability, and integrity of the LVL board.

[0090] The LVL board of Figure 5 consists of veneer sheets of four different lengths / i, h, h and h. These 4 lengths form a first pair lengths Zi and h and a second pair lengths h and h. In odd layers of the LVL board, every other veneer sheet has the length h and every other the length h. On the other hand, in even layers of the LVL board, every other veneer sheet has the length h and every other the length h. These lengths have been selected such that l±+ l2= I3 + Z4. For example, the lengths Zi, h, h and h may have values h = 2.55 m, h = 2.10 m, h = 2.40 m and h = 2.25 m. The seams or (scarf) joints across the veneer layers are staggered. However, the distance between adjacent seams or (scarf) joints in two adjacent veneer layers of the LVL board is not constant across the LVL board.

[0091] Comparing the alternatives of Figures 4 & 5, the alternative of Figure 4 has the benefit of being simpler to implement. Assuming that a separate veneer feeding station is required for each veneer length used in the top veneer layer, for each veneer length used in the bottom veneer layer and for each veneer length used in the middle veneer layers in a continuous LVL production process, the total number of veneer feeding stations required may be equal to 6 in this example (or 8 if the middle veneer layers are assumed to contain both flipped and non-flipped veneer sheets). On the other hand, the total number of veneer feeding stations required for implementing the LVL board of Figure 5 may be equal to 8. Also, the programming required for implementing the automated lay-up process is more complicated for Figure 5 compared to Figure 4. The constant staggering of the adjacent veneer layers used in Figure 4 may also be considered beneficial in view of the structural strength, stability, and integrity of the LVL board compared to the non-constant staggering of Figure 5.

[0092] On other hand, the alternative of Figure 5 is beneficial over the alternative of Figure 4 in the sense that it enables using larger number of different veneer lengths in a single production batch. The LVL board production employing a large number of different veneer lengths is more efficient when larger number of different veneer lengths may be employed in a given production batch.

[0093] Figure 6 provides an apparatus 601 according to some embodiments. Specifically, the apparatus 601 may be a control computing device 122 of a log sorting system 105 as discussed in connection with Figure 1.

[0094] The apparatus 601 may comprise one or more (communication) control circuitry 620, such as at least one processor, and at least one memory 630, including one ormore algorithms 631 (instructions), such as a computer program code (software) wherein the at least one memory and the computer program code (software) are configured, with the at least one processor, to cause the apparatus to carry out any one of the exemplified functionalities of the control computing device described above. Said at least one memory 630 may also comprise at least one database 632.

[0095] When the one or more communication control circuitry 620 comprises more than one processor, the apparatus 601 may be a distributed device wherein processing of tasks takes place in more than one physical unit. Each of the at least one processor may comprise one or more processor cores. The one or more control circuitry 620 may comprise at least one application-specific integrated circuit (ASIC). The one or more control circuitry 620 may comprise at least one field-programmable gate array (FPGA).

[0096] Referring to Figure 6, the one or more control circuitry 620 of the apparatus 601 are configured to carry out (or at least cause or trigger carrying out) any of the functionalities described above by means of any of blocks 202 to 206 of Figure 2 using one or more individual circuitries.

[0097] Referring to Figure 6, the apparatus 601 may further comprise different interfaces 610 such as one or more communication interfaces comprising hardware and / or software for realizing communication connectivity according to one or more communication protocols. Specifically, the one or more communication interfaces 610 may comprise, for example, communication interfaces providing a connection to an X-ray scanner and / or a conveyor system of the log sorting system and / or to an external database for storing, e.g., selected sawing patterns and identifiers of logs. The one or more communication interfaces 610 may comprise standard well-known components such as an amplifier, filter, frequencyconverter, (de)modulator, and encoder / decoder circuitries, controlled by the corresponding controlling units, and one or more antennas. The apparatus 601 may also comprise one or more user interfaces.

[0098] Referring to Figure 6, the memory 630 may be implemented using any suitable data storage technology, such as semiconductor based memory devices, flash memory, magnetic memory devices and systems, optical memory devices and systems, fixed memory and removable memory.

[0099] As used in this application, the term ‘circuitry’ may refer to one or more or all of the following: (a) hardware-only circuit implementations, such as implementations in only analog and / or digital circuitry, and (b) combinations of hardware circuits and software (and / or firmware), such as (as applicable): (i) a combination of analog and / or digital hardware circuit(s) with software / firmware and (ii) any portions of hardware processor(s) with software, including digital signal processor(s), software, and memory(ies) that work together to cause an apparatus, such as a terminal device or an access node, to perform various functions, and (c) hardware circuit(s) and processor(s), such as a microprocessor(s) or a portion of a microprocessor(s), that requires software (e.g. firmware) for operation, but the software may not be present when it is not needed for operation. This definition of ‘circuitry’ applies to all uses of this term in this application, including any claims. As a further example, as used in this application, the term ‘circuitry’ also covers an implementation of merely a hardware circuit or processor (or multiple processors) or a portion of a hardware circuit or processor and its (or their) accompanying software and / or firmware.

[0100] In an embodiment, at least some of the processes described in connection with Figures 1 and 2 may be carried out by an apparatus comprising corresponding means for carrying out at least some of the described processes. Some example means for carrying out the processes may include at least one of the following: detector, processor (including dualcore and multiple-core processors), digital signal processor, controller, receiver, transmitter, encoder, decoder, memory, RAM, ROM, software, firmware, display, user interface, display circuitry, user interface circuitry, user interface software, display software, circuit, filter (low-pass, high-pass, bandpass and / or bandstop), sensor, circuitry, inverter, capacitor, inductor, resistor, operational amplifier, diode and transistor. Said means may comprise the imaging means described above. In an embodiment, the at least one processor, the memory, and the computer program code form processing means or comprises one or more computer program code portions for carrying out one or more operations according to any one of the embodiments of Figures 1 and 2 or operations thereof. In some embodiments, at least some of the processes may be implemented using discrete components.

[0101] In some embodiments, there is provided an apparatus for a log sorting system, wherein the apparatus comprises means for performing: detecting a log in the log sorting system; causing an X-ray scanner of the log sorting system to scan the log; obtaining one or more candidate sawing patterns for the log by eitherreceiving results of the scanning from the X-ray scanner and determining one or more candidate sawing patterns of the log based on the results of the scanning or receiving the one or more candidate sawing patterns determined by the X-ray scanner based on the results of the scanning from the X-ray scanner; comparing the determined one or more candidate sawing patterns against a plurality of pre-defined sawing patterns associated with a respective plurality of pre-defined values of a sawing pattern utility metric to find one or more values of the sawing pattern utility metric for the one or more candidate sawing patterns; classifying the log to one of a first category or a second category based on the one or more values of the sawing pattern utility metric, wherein the first category is defined for logs to be processed in a sawmill and the second category is defined for logs to be processed in a laminated veneer lumber, LVL, mill, the first category being defined for logs having higher sawing pattern utility compared to the second category; and causing sorting of the log based on the classification by guiding it to one of one or more first trays corresponding to the first category or to one of one or more second trays corresponding to the second category.

[0102] The means mentioned in the previous paragraph may comprise at least at least one processor and at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus at least to perform the above listed steps.

[0103] Embodiments as described may also be carried out, fully or at least in part, in the form of a computer process defined by a computer program or portions thereof. Embodiments of the methods described in connection with Figures 1 and 2 may be carried out by executing at least one portion of a computer program comprising corresponding instructions. The computer program may be provided as a computer readable medium comprising program instructions stored thereon or as a non-transitory computer readable medium comprising program instructions stored thereon. The computer program may be in source code form, object code form, or in some intermediate form, and it may be stored in some sort of carrier, which may be any entity or device capable of carrying the program. For example, the computer program may be stored on a computer program distribution medium readable by a computer or a processor. The computer program medium may be, for example but not limited to, a record medium, computer memory, read-only memory, electrical carrier signal, telecommunications signal, and software distribution package, for example. The computer program medium may be a non-transitory medium. Coding of software forcarrying out the embodiments as shown and described is well within the scope of a person of ordinary skill in the art.

[0104] In some embodiments, there is provided a computer program comprising instructions which, when the computer program is executed by a computer of a log sorting system, cause the computer to carry out: detecting a log in the log sorting system; causing an X-ray scanner of the log sorting system to scan the log; obtaining one or more candidate sawing patterns for the log by either receiving results of the scanning from the X-ray scanner and determining one or more candidate sawing patterns of the log based on the results of the scanning or receiving the one or more candidate sawing patterns determined by the X-ray scanner based on the results of the scanning from the X-ray scanner; comparing the determined one or more sawing patterns against a plurality of pre-defined sawing patterns associated with a respective plurality of values of a sawing pattern utility metric to find one or more values of the sawing pattern utility metric for the one or more candidate sawing patterns; classifying the log to one of a first category or a second category based on the one or more values of the sawing pattern utility metric, wherein the first category is defined for logs to be processed in a sawmill and the second category is defined for logs to be processed in a laminated veneer lumber, LVL, mill, the first category being defined for logs having higher sawing pattern utility compared to the second category; and causing sorting of the log based on the classification by guiding it to one of one or more first trays corresponding to the first category or to one of one or more second trays corresponding to the second category.

[0105] The term “non-transitory”, as used herein, is a limitation of the medium itself (that is, tangible, not a signal) as opposed to a limitation on data storage persistency (for example, RAM vs. ROM).

[0106] Reference throughout this specification to one embodiment or an embodiment means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present solution. Thus, appearances of the phrases “in one embodiment” or “in an embodiment” in various places throughout this specification are not necessarily all referring to the same embodiment.

[0107] As used herein, a plurality of items, structural elements, compositional elements, and / or materials may be presented in a common list for convenience. However, these lists should be construed as though each member of the list is individually identified as a separate and unique member. Thus, no individual member of such list should be construed as a de facto equivalent of any other member of the same list solely based on their presentation in a common group without indications to the contrary. In addition, various embodiments and example of the present solution may be referred to herein along with alternatives for the various components thereof. It is understood that such embodiments, examples, and alternatives are not to be construed as de facto equivalents of one another, but are to be considered as separate and autonomous representations of the present solution.

[0108] Even though embodiments have been described above with reference to examples according to the accompanying drawings, it is clear that the embodiments are not restricted thereto but can be modified in several ways within the scope of the appended claims. Therefore, all words and expressions should be interpreted broadly and they are intended to illustrate, not to restrict, the embodiment. It will be obvious to a person skilled in the art that, as technology advances, the inventive concept can be implemented in various ways. Further, it is clear to a person skilled in the art that the described embodiments may, but are not required to, be combined with other embodiments in various ways.

Claims

CLAIMS1. A method for log processing at a laminated veneer lumber, LVL, mill, the method comprising: cross-cutting a plurality of logs having a plurality of different lengths, wherein the cross-cut logs comprise logs of a plurality of different lengths; peeling the cross-cut logs using a peeler capable of processing logs of different lengths to produce a plurality of veneer sheets; cutting the plurality of veneer sheets to a pre-defined width, wherein the predefined width is independent of a length of a veneer sheet; and creating LVL boards from the plurality of veneer sheets having the pre-defined width.

2. The method of claim 1, further comprising: debarking the plurality of logs before the cross-cutting; or soaking the plurality of logs before the cross-cutting or between the crosscutting and the peeling; or debarking the plurality of logs before the cross-cutting and soaking the plurality of logs between the debarking and the cross-cutting or between the cross-cutting and the peeling.

3. The method of claim 1 or 2, wherein the creating of the LVL boards comprises: scarfing the plurality of veneer sheets.

4. The method according to any of claims 1 to 3, wherein the creating of the LVL boards from the plurality of veneer sheets comprises, for each created LVL board: stacking veneer sheets of the same length and the same pre-defined width to form a veneer lay-up, wherein an adhesive is applied onto the multiple veneer sheets before and / or during the stacking; and pressing, using at least one press, the veneer lay-ups to form an LVL board.

5. The method of claim 3, wherein the creating of the LVL boards from the plurality of veneer sheets comprises, for each created LVL board: after the scarfing, stacking veneer sheets of a plurality of different lengths and the same pre-defined width to form a veneer lay-up, wherein an adhesive is applied onto the multiple veneer sheets before and / or during the stacking, and scarf joints are staggered in the veneer lay-up, the staggering of the scarf joints being uniform or non-uniform across the veneer lay-up; and pressing, using at least one press, the veneer lay-ups to form an LVL board.

6. The method of claim 5, wherein the stacking of the veneer sheets comprises: forming each layer of the veneer lay-up from veneer sheets of two or more different lengths so that different lengths of veneer sheets are alternated within the layer according to a pre-defined alternating pattern.

7. The method of claim 5, wherein the stacking of the veneer sheets comprises: forming every odd-numbered layer of the veneer lay-up from veneer sheets of two or more first lengths so that the two or more first lengths of veneer sheets are alternated within the layer according to a first pre-defined periodic alternating pattern, wherein the two or more first lengths occur an equal number of times, per period, in the first pre-defined periodic alternating pattern; and forming every even-numbered layer of the veneer lay-up from veneer sheets of two or more second lengths so that the two or more second lengths of veneer sheets are alternated within the layer according to a second pre-defined periodic alternating pattern, wherein the two or more second lengths occur said equal number of times, per period, in the second pre-defined periodic alternating pattern, the two or more second lengths are different from the two or more first lengths, and the two or more first lengths and the two or more second lengths are defined so that the sum of the two or more first lengths is equal to a sum of the two or more second lengths.

8. The method according to any of claims 1 to 7, wherein the peeler is a spindless peeler for enabling the processing of logs of different lengths.

9. The method according to any of claims 1 to 7, wherein the peeler comprises an adjustable spindle for enabling the processing of logs of different lengths.

10. The method according to any of claims 1 to 9, wherein the plurality of different lengths of the cross-cut logs are within the range of 1250 mm - 3000 mm, and the peeler is configured to process at least logs having a length within the range of 1250 mm - 3000 mm.

11. The method according to any preceding claim, further comprising: executing, before the processing at the LVL mill, an automated log sorting process by a log sorting system for a set of logs of a plurality of different lengths, wherein the automated log sorting process, for each of the set of logs, comprises:- receiving a log in the log sorting system;- scanning, by an X-ray scanner of the log sorting system, the log;- determining, by a computing device of the log sorting system or by the X-ray scanner, one or more candidate sawing patterns for the log based on results of the scanning;- comparing, by the computing device, the determined one or more candidate sawing patterns against a plurality of pre-defined sawing patterns associated with a respective plurality of values of a sawing pattern utility metric to find one or more values of the sawing pattern utility metric for the one or more candidate sawing patterns;- classifying, by the computing device, the log to one of a first category or a second category based on the one or more values of the sawing pattern utility metric, wherein the first category is defined for logs to be processed in a sawmill and the second category is defined for logs to be processed in the LVL mill, the first category being defined for logs having higher sawing pattern utility compared to the second category; and- sorting the log based on the classification by guiding it to one of one or more first trays corresponding to the first category or to one of one or more second trays corresponding to the second category, wherein the plurality of logs are sorted into the second category during the automated log sorting process.

12. The method of claim 11, further comprising: following the sorting of the set of logs, transporting or conveying the plurality of logs sorted to the second category to the LVL mill.

13. The method of claim 11 or 12, wherein each of the one or more candidate sawing patterns defines sawing of a center piece and side boards of the log.

14. The method according to any of claims 11 to 13, wherein the one or more candidate sawing patterns comprise or consist of: all sawing patterns suitable for sawing the log based on the results of the scanning; or a pre-defined number of sawing patterns most suitable for sawing the log based on the results of the scanning, wherein the pre-defined number is equal to or larger than one.

15. The method according to any of claims 11 to 14, wherein the classifying comprises: in response to highest of the one or more values of the sawing pattern utility metric satisfying one or more pre-defined criteria for high sawing pattern utility, classifying the log to the first category; and in response to highest of the one or more values of the sawing pattern utility metric failing to satisfy the one or more pre-defined criteria for high sawing pattern utility, classifying the log to the second category.

16. The method of claim 15, wherein the one or more pre-defined criteria comprise a pre-defined threshold for the sawing pattern utility metric.

17. The method according to any of claims 11 to 16, wherein the sawing pattern utility metric is a metric dependent at least on a current value and / or a current demand for one or more different sawn timber products prepared by using an associated sawing pattern in the sawmill.

18. The method according to any of claims 11 to 17, wherein the determining of the one or more candidate sawing patterns is based on a diameter, a length and a quality of the log, being optionally in a form of a three-dimensional quality pattern, as determined from the results of the scanning and pre-defined diameter, length and quality requirements of sawn timber products associated with different sawing patterns.

19. The method according of claim 18, wherein the quality of the log is dependent on one or more of the following: straightness of the log, uniformity of the log, moisture content of the log, soundness of the log, grain orientation of the log, a ratio of heartwood to sapwood in the log, number of defects in the log, locations of the defects in the log and types of the defects in the log.

20. The method according to any of claims 11 to 19, further comprising, in response to the log being classified to the first category: selecting a candidate sawing pattern of the one or more candidate sawing patterns having the highest value of the sawing pattern utility metric as a sawing pattern of the log; and storing the results of the scanning and / or a log identifier calculated based on the results of the scanning and / or the sawing pattern for the log to an external database accessible by a laser, optical or X-ray scanner of the sawmill for enabling identification of the log and determining of the sawing pattern of the log at the sawmill.

21. The method according to any of claims 11 to 20, wherein all or at least one of the set of logs are pine logs.

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