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During the last 10–20 years European sawmilling and plywood industry R&D has concentrated on increasing the speed of sawing machines and rotary lathes and increasing the productivity. The industry is characterised by bulk production and inefficient raw material use. This is the case all over the Europe, although some regional variations exist. The country-specific descriptions are provided at the end of this section.
All processes from forest to end product’s use have to be effective with low environmental burden. Compared to existing processes, critical improvements can be made by adding more flexibility to the wood value chains, i.e. products and product families determine configuration of value chains and production systems. From a value creation point of view, the most critical phase is harvesting, where stems are cut-to-length and thus the logs’ value (i.e. quality) is determined. As wood raw material is by the far the major production cost at sawmills being in the region of 65-70 %, even a small change in the raw-material cost (or value yield) can give major increase in sawmills’ profitability. Apart from current harvesting methods, stems should be cut-to-length according to their internal characteristics because in the end, the product’s true value depends on its aesthetic and other characteristics that cannot be evaluated properly with current methods.
European woodworking industry has to be revived in order to enhance its competitive advantage. Solutions for the challenge are sought through Wood allocation centre – concept proposed at VARMA project with following objectives:
- Introduction of radically novel customer-oriented business models and services
- Higher wood raw material utilisation ratio and improved value yield
- Means for increased cooperation (i.e. flexibility and efficiency) via networking within wood value chains
The project goal is to develop customer driven value chains and wood raw material allocation system by implementing smart bucking center for stems. Figure 1 illustrates the proposed Wood allocation centre – concept (WAC), where the fundamental idea is to deliver the right product to the right customer in a timely manner with the highest possible value added.
Independently operated centre serves several mills (sawmills, plywood, converters) forming a network with ability to specialise to certain product. At the centralised bucking centre, delivered stems are measured accurately (geometrical and quality features) prior bucking. This means implementation of x-ray scanners or available non-destructive technics, enabling detailed information concerning internal characteristics, such as knots, faults, annual rings, strength etc. Based on measured stem data and networking mills’ order files, software to be developed, calculates optimal bucking procedure for the stems. The goal in this all is that the highest value potential is gained from each stem and the customers can be served better while waste wood volume is minimised.
Philosophy - “The stronger the linkages between the primary and secondary producer the greater the source of competitive advantage for all”
- CLAYTON CHRISTISON - HARVARD BUSINESS SCHOOL
The industry is using cut-to-length method, where bucking is based only on rough human assessment of quality, harvester diameter measurements and control matrices. Allocation is not based on accurate scanning of wood properties. This situation causes big economic losses due to mismatch between available wood raw material and products to be manufactured. Networking between the companies (sawmills, converters, retail, customers) does not exist, even indisputable benefits from cooperation have been found. At the same time, the sector is suffering financial difficulties. Despite the fact that in many cases the technology in use is highly advanced (scanners, image processing tools etc.), old fashioned business models are still applied. Main measurements are still length, diameter, ovality and curvature that serve the purpose of volume maximisation very well, but do not help the industry to move from bulk production to high value added products. X-ray technology alone is already a critical improvement for the industry. However, combination of decent measurements, optimisation/allocation system and ability communicate (i.e. information system) within the network of wood value chains can open whole new opportunities in terms of value creation in production as well as emergence of novel services.
Harvesting of long logs for both conifers and broadleaves was dominant until the 1970. The logs were cross cut at sawmills according to specifications of their actual customer demands. The capacities at sawmills increased rapidly and they were not able to handle any more long logs on a tree by tree basis. From there on two developments took place: Mostly at the big mills, cut to length systems where introduced together with harvester-forwarder systems in the forest, and the saw mills produced standard length for mass product markets. SME’s retained in the long log concept and mechanised their wood yards with 3D-log scanning and calculators for optimization. Parallel to this, forest owners cooperated to install own wood yards (Holzhof) where they crosscut the long logs according to their customers wishes (small sawmills). This concept survived for about 20 years, which after the added value of crosscutting on demand was lower than the related cost (transport, installation of wood yards) and the wood yards where closed down. Recently, the demand for wood and especially for saw logs has increased drastically due to growing capacity in the saw mill industry and increasing competition from the wood energy markets. Subsequently the raw material prices sharply increased and parallel to this, a relative gain in volume and value recovery is urgently needed from the saw milling sector to be able to run their production at full capacity and to create the necessary revenue out of their operation. A renaissance of long log deliveries emerged again due to better utilisation ratio of the resources.
A growing share of the sawmills are getting more and more specialized, producing specific products which are generally more demanding in terms of optimal log dimensions, while also additional properties, like knot, strength, durability, surface, aesthetic properties etc. may be of larger or smaller importance depending on the target products. Determining which logs to order and process, with which sawing patterns to achieve an optimal result is a demanding problem to solve. The need to consider different log purchase options, market opportunities and production constraints, it becomes obvious that making optimal operating decisions with conventional planning methods is impossible. Consequently there is a need for decisions support systems and technology that facilitates accessibility to decisive information.
In France, the bucking operations are carried on the log yards of sawmills. They are based on dimensional criteria and qualitative criteria estimated visually. This operation does not make the best material, and often the cost of wrong sorting is high. The relative low efficiency of bucking in the woods is due to a low evaluation of real wood quality and ignorance of the customer's requests. The few trials of timber yard concentration outside sawmill, were inconclusive.
Tests are conducted regularly but the added value of transactions made on the yard was not sufficient to cover the extra cost of handling. An optimized sorting would make these operations profitable, by providing an opportunity to more closely examine log characteristics. The probability of making an incorrect log allocation will be decreased, and the harvested timber will be best promoted. The only centralized sort yards under development actually in France are intended primarily for wood energy. In this case the transactions on the log yard (crushing, sorting, chips drying,..) allow this operation to be profitable.
The UK sawmill industry has developed significantly in the last 10 years, with the principal players developing high value processing units, maximising yields from short log harvesting systems. Changes in timber quality, a consolidation towards Sitka spruce and the high demand for wood has forced the sawmill sector to use as much technical advantage as it can find, in order to maximise the utilisation and yield recovery from each log cut. The market in the UK requires material to be produced in 4.8m lengths which further stretches the requirements for log and tree optimisation. High tech 3D scanners and optimisers are used to allow for log profiling and curved sawing enables high yield levels from aesthetically poor logs. The issue is with quality of logs being grown and sawn in the UK. With premature harvesting to meet the current demands and achieve forest rationalisation, the log quality appears to be poorer than other years. There is also an issue with seed stock or genetics in relation to branching and internal wood properties. New technology in the value chain would allow for a better decision processes to be addressed giving potentially more opportunities. The sector needs to be able to react with more efficiency to allow for less waste and more productivity, not just at the mill but through the range.