Solidiwood wood products replace traditional value-added sawn timber products as intermediate and end products. They cover the whole field of construction, such as frame structures, exterior and interior cladding, joinery products, and yard and garden products. They are also needed in furniture and other products.
The Solidi business ecosystem / Solidiwood technology enable Solidiwood wood products to achieve a superior price-quality ratio.
Topographic surface coated with paper-industry coating paste
Traditional techniques, even when carried out with different equipment and at different times, cannot deliver the product properties produced with Solidiwood, let alone the product-specifically optimised, cumulative overall result of the properties listed below and the cost-efficiency of producing them.
Compact Solidiwood process technology enables 2-3D hot-press drying of products, heat treatment, stress relief, straightening, increased bending strength and stiffness, gluing from several parts, fixed lengths, profiling and dimensioning, as well as densified smooth, topographic or structured surfaces, together with their pressurised patching and coating with various substances and/or films.
.
Solidiwood process technology hot-forms sawn timber in 2-3D directions into high-grade processed products in a single device / process.
In Solidiwood process technology, the pressure-impregnation-like treatment of product blanks is carried out both with the wood material's own binders and with added treatment chemicals/materials, selected from among impregnating agents, fillers/primers, surface treatment agents and adhesives/films/scrims. Particular possibilities also worth mentioning are the use of plastics and of nano-scale cellulose fibrils. All of this also applies, where relevant, to the products of product group 3.
The formation of the product profile and of dense, intact, more homogeneous, smooth, topographic or structured surfaces is improved by using the above-mentioned chemicals/materials and water.
Solidiwood process technology gives Solidiwood wood products a superior price-quality ratio.
As a starting point, it makes most sense to design and produce Solidiwood press units tailored to each application area / product. This enables maximum cost-efficiency and the best price-quality ratio for the products.
However, the overall business situation should always be examined case by case, taking other essential factors affecting the result into account as well.
There are particularly good grounds for seeking to reduce the number of different products, right up to product standardisation. The product range grows with the number of variables taken into production, such as the species, dimensions and grades of sawn timber and the cross-sectional profiles, moisture contents and coatings of the end products.
Below is an example of a multi-purpose product, together with its rationale. This should provide ideas and grounds for the open-minded further development of the technology and of products in the other product groups too, based on the overall business situation.
Solidiwood multi-purpose board product
The Solidiwood multi-purpose board product described below is made with the same press unit and is at its best as exterior and interior cladding and as load-bearing decking and flooring board. Using exterior cladding and decking boards, and likewise interior cladding and flooring boards, as the same product is made possible by the very fact that they share the same service conditions in terms of moisture. Otherwise, the application-specific changes described below are made in production. The required sawn timber is procured, for example, as 25 and 16 x 200 x 540 cm fixed lengths or ready for butt-joint extension, green or shipping dry. Solidiwood process technology also makes possible a radically more favourable price-quality ratio than traditional methods for such massive “manor house” boards.
The end user decides where to use the product and which of its faces to leave visible: the smooth or the topographic one, with chamfered/rounded edges, and with what coating. At its best, it is surface-treated, i.e. protected on all its surfaces, including against wetting. The user can also install a product that has already been in use in a new location. This is most justified at the so-called father-to-son stage.
A multi-purpose product of this kind is certain to interest all parties, from the suppliers of the technology, sawn timber and coatings, through warehousing, transport and retailers, right up to end users. The product's market potential would grow considerably, and operations would become simpler at every stage.
What matters is that everything relating to the press unit, i.e. the size of the sawn timber and the cross-sectional profile of the multi-purpose product, stays the same. Each unit is run with a slightly different production programme as the wood species, the grade of the sawn timber, the initial/final moisture content of the product, the coating, and whether the coating is applied from a vessel or as films, change.
There are three alternatives, set out below, for the cross-sectional profile of the multi-purpose product. The best of these will be determined experimentally.
Rationale
It is a good idea to use the above-mentioned Dauerholz device when installing the multi-purpose board product, so that the exterior cladding, decking and flooring are tight and otherwise installed to a high standard. Unlike with the Dauerholz decking board, the counterforce the device needs is obtained from the fixings to the battens. Even when used as flooring, the boards do not need end tongue-and-groove joints. These can be replaced by gluing the end faces together during installation.
In all applications the product can be fastened to the battens by screwing diagonally through the side face of the board, or through the board into the battens. The latter method is also suitable for flooring boards, because it is traditional and because of the boards' great width.
The multi-purpose product is put to use as exterior cladding by means of a traditional board-and-batten solution. This solution avoids the need for the thin tongue-and-groove joint area of conventional planed exterior cladding, which is by far the worst area in terms of fire risk. In this way the weakest area can be made even more fire-safe than the rest of the board cladding.
In exterior cladding, whether the boarding is vertical or horizontal, a cover strip made of fire-safe material, which emphasises the striking appearance of the cladding, is installed in place of the traditional cover batten. The boards can also be fastened to the battens by screwing through the cover strip. See the exterior cladding drawing
It is advisable to coat exterior cladding boards with fire-retardant paint, and decking and flooring boards with paraffin, for the same reasons as the Dauerholz decking board. Coating is carried out either as a liquid or as films See also Piloting and Fine-tuning the process. Changing the liquid coating requires changing the vessel, and changing the sleeve-film coating correspondingly requires changing the roller set. Exterior cladding boards destined for spaces more humid than indoors can, for example, be moistened in the press or in a humid space before installation, and wetting does little harm to decking boards even once they are installed in place. At best, the moisture content of a multi-purpose board suited to all uses can also be the same, provided that wetting and drying can be kept so low through protection that no harmful changes in volume occur.
Besides exterior cladding, other uses for boards coated with fire-retardant paint, especially in apartment buildings, could be interior cladding, decking and flooring. A board length of 540 cm yields two high-grade cladding boards, each long enough to cover a full storey height, even on the exterior.
At the core of the heavy-section products is the production of wall and intermediate floor elements, as well as columns and beams. These are most economical to manufacture mainly from small-diameter sawlogs, using sawn blanks pre-profiled during sawing. The blanks are either the length of the fixed-length sawlog or are made ready for finger-jointing before the process.
Reducing the settlement of log and other timber walls makes high-rise construction possible, as well as combining wood with steel and glass. Wood withstands compression along its length many times better than across the grain, and its moisture movement is correspondingly smaller.
CLT elements have for decades been made of cross-glued boards, so some of the boards in a wall run vertically. The same is also possible with LVL elements: “Depending on the LVL product, the grain of all the veneers runs lengthwise, or some of the veneers are glued crosswise.”
Only in recent years have laminated logs begun to be manufactured so that the lamellas in the middle of the log are installed vertically.
The settlement of Solidiwood log and other timber wall elements is smaller than in the above, because their
For example, a massive Solidiwood log wall element is produced by adding to its vertical, i.e. wall element, blank horizontal boards which, when an oversized log is sawn, are taken from its surface and profiled to resemble round logs. They can be pressed using, for example, a compressed-air-filled element on the surfaces of the press plates. At the same time, the log wall acquires topographic surfaces, surface-treated as desired.
Boards suited to the intended use can be pressed / coated onto other Solidiwood elements, or other surface materials can be installed afterwards.
All Solidiwood elements are used in the same way as CLT wall elements.
The profiling of the sawn blanks and the side-pressing tools is made optimal for the process and the end product by means of strength calculations and compression tests. The images below are primarily only schematic drawings, which are modified on a case-by-case basis.
During pressing, the pressing force must be taken up in the cavities by a moisture-permeable support, e.g. a perforated metal support; otherwise it is concentrated too heavily on the centre board.
The cavities of the elements, as well as those of the pillars and beams, work particularly well for removing moisture and also in the product-specific optimisation of the removal of heat and of pressing and steam pressure.
The products can always be produced ready-finished, right down to surface treatment. In an intermediate floor, for example, this means finished floor and ceiling surfaces.
The size of the element, pillar and beam in the images below increases in direct proportion to an increase in the diameter class of the sawlog.
Wall and intermediate floor elements are obtained from the beams in the images below by pre-profiling tongue-and-groove elements onto the vertical side faces of the upper and lower parts of the beam during sawing. When a separate board pre-profiled with tongue and groove is used as the centre board, the lower and upper parts of the beam come out of the sawing more massive from the same sawlog diameter. For example, a thinner partition wall element also requires a narrower centre board. This can also be obtained by pressing it narrower in the process.
Even centre boards of the thickness shown in the image are sufficient for both elements. In this case, the centre boards of the beams of the wall and intermediate floor elements must be aligned with each other at the junction of the elements. Together they form 4 x thicker (more) wood than conventional 50 mm battens and vertical studs at 600 mm c/c.
Otherwise, with the beam shown in the image, the limiting factor in elements and in other horizontal uses is the joint strength (shear, compressive and tensile strength) that governs its dimensioning. This strength can also be increased by pressing the centre board thicker and/or narrower. For other applications, a separate and different Solidiwood beam product can be produced.
Four sawn blanks to form a pillar
Profiling sawing solution for the technically and economically superior, high end-product-yield pillar patented by Hammarström, supplemented with tongue-and-groove members.
Required small-log diameter class 13 cm.
New engineered wood product 100 x100 pillar.
Three sawn blanks to form a beam
Profiling sawing solution for a technically and economically superior beam with a truly high end-product yield.
Required small-log diameter class 11 cm.
New engineered wood product 75 x 150 beam