CN103433983B - High-performance laminated veneer lumber panel and production method thereof - Google Patents
High-performance laminated veneer lumber panel and production method thereof Download PDFInfo
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- CN103433983B CN103433983B CN201310348237.4A CN201310348237A CN103433983B CN 103433983 B CN103433983 B CN 103433983B CN 201310348237 A CN201310348237 A CN 201310348237A CN 103433983 B CN103433983 B CN 103433983B
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- 238000004519 manufacturing process Methods 0.000 title claims abstract description 18
- 239000010410 layers Substances 0.000 claims abstract description 70
- 238000005452 bending Methods 0.000 claims abstract description 17
- 239000005011 phenolic resin Substances 0.000 claims abstract description 17
- 229920001568 phenolic resins Polymers 0.000 claims abstract description 17
- 238000007731 hot pressing Methods 0.000 claims abstract description 8
- 239000011248 coating agents Substances 0.000 claims abstract description 3
- 238000000576 coating method Methods 0.000 claims abstract description 3
- 238000007598 dipping method Methods 0.000 claims description 30
- 239000000463 materials Substances 0.000 claims description 22
- 230000001186 cumulative Effects 0.000 claims description 13
- 238000005315 distribution function Methods 0.000 claims description 13
- 239000007787 solids Substances 0.000 claims description 11
- 238000002803 maceration Methods 0.000 claims description 9
- 229920005989 resins Polymers 0.000 claims description 9
- 239000011347 resins Substances 0.000 claims description 9
- 238000004026 adhesive bonding Methods 0.000 claims description 8
- 238000003892 spreading Methods 0.000 claims description 4
- 230000005540 biological transmission Effects 0.000 claims description 2
- 238000001816 cooling Methods 0.000 claims description 2
- 230000000875 corresponding Effects 0.000 claims description 2
- 238000001514 detection method Methods 0.000 claims description 2
- 238000005299 abrasion Methods 0.000 abstract description 3
- 230000001070 adhesive Effects 0.000 abstract description 3
- 239000000853 adhesives Substances 0.000 abstract description 3
- 230000003014 reinforcing Effects 0.000 abstract 2
- 239000002344 surface layers Substances 0.000 abstract 2
- 238000001035 drying Methods 0.000 abstract 1
- 239000002023 wood Substances 0.000 description 15
- 230000000052 comparative effects Effects 0.000 description 7
- 238000007654 immersion Methods 0.000 description 6
- 238000000034 methods Methods 0.000 description 6
- 241001081830 Degeneriaceae Species 0.000 description 5
- 241000218231 Moraceae Species 0.000 description 5
- 238000005516 engineering processes Methods 0.000 description 4
- 235000008593 Pinus contorta Nutrition 0.000 description 3
- 241000218606 Pinus contorta Species 0.000 description 3
- 230000002708 enhancing Effects 0.000 description 2
- 239000003292 glue Substances 0.000 description 2
- 239000011901 water Substances 0.000 description 2
- 229920002521 Macromolecule Polymers 0.000 description 1
- 238000010521 absorption reactions Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 238000005470 impregnation Methods 0.000 description 1
- 239000005022 packaging materials Substances 0.000 description 1
- 238000003672 processing method Methods 0.000 description 1
- 239000002994 raw materials Substances 0.000 description 1
- 230000001629 suppression Effects 0.000 description 1
Abstract
Description
Technical field
The present invention relates to a kind of production method of high-performance laminated veneer lumber sheet material, specifically, is the method utilizing common wood or inferior grade timber high efficiency manufacture high-performance laminated veneer lumber sheet material.
Background technology
Laminated veneer lumber sheet material be rotary-cut after wood single-plate through gluing, rift grain assembly, compacting a kind of Novel engineering structural material, because its stable performance, intensity are high, be easy to the advantages such as processing, alternative large footpath level solid sawn lumber use, be subject to the favor in market.
Laminated veneer lumber sheet material comprises two large classes, and one is laminated veneer lumber plate (laminated veneer board, LVB), and one is (thicker) laminated veneer lumber (laminated veneer lumber, LVL).Laminated veneer lumber plate width is far longer than thickness, is commonly used for compartment board.(thicker) laminated veneer lumber general thickness is greater than 30mm, is commonly used for beam or post.
But the production technology level of China's laminated veneer lumber sheet material is relatively backward, be difficult to meet the requirement of market to high-performance laminated veneer lumber sheet material.Summarize, weak point is: wood single-plate variability is large, causes properties of product unstable, affects the engineering design of timber compoment; The veneer dipping enhancing processing method time is long, cost is high, hinders the marketing of veneer dipping enhancing technology; Structure of plate slab is unreasonable, causes the mechanical property of product (as MOR, shear strength, elastic modelling quantity, anti-wear performance) lower, and size is unstable.
Summary of the invention
The object of this invention is to provide a kind of high strength, high elastic modulus, high-dimensional stability, the high-performance laminated veneer lumber sheet production method of high-wearing feature and low variability, the method can make full use of common wood or inferior grade timber resources, manufacture high-performance laminated veneer lumber sheet material, may be used for platform floor, building template and container bottom board (laminated veneer lumber plate), large span carrying beam column and the packing case fields such as thicker packaging material (laminated veneer lumber), to alleviation timber supply and demand contradiction, realize the excellent use of bad material, the surcharge increasing wood utilization has very large realistic meaning.
The production method of high-performance laminated veneer lumber sheet material of the present invention, comprises the steps:
A. veneer grades: according to the size of dynamic modulus of elasticity MOE of often opening veneer, veneer is divided into high and low two grades or high, medium and low Three Estate;
B. phenolic resin with two components maceration extract is configured: the pf resin of low molecular weight of the high molecular weight phenolic resin of molecular weight 1000-2000 and molecular weight 200-1000 is mixed in the ratio of 2:8-8:2, and final phenolic resin with two components maceration extract solid content is 30-50%;
C. veneer dipping: high or middle grade veneer soaks 5-10 minute to part with maceration extract, soaks 3-8 minute to part inferior grade veneer, to the veneer dry 1.0-1.5 hour at 40-70 DEG C of temperature after dipping, makes the Veneer moisture after dipping reach 9-12%;
D. veneer gluing: to untreated veneer coating general commercial synvaren, single spreading amount is 120-180g/m 2;
E. veneer assembly:
1. laminated veneer lumber plate assembly scheme:
Be followed successively by top layer, balance layer, sandwich layer, balance layer, bottom from top to bottom, symmetrical with sandwich layer;
Top layer and bottom are 1 to 2 floor height or middle grade dipping veneer, and its grain parallel is in panel length direction;
Balance layer is 1 floor height or the middle and low grade dipping veneer, and its grain perpendicular is in panel length direction;
Sandwich layer is in several or inferior grade blanket glued veneer, and its grain parallel is in panel length direction;
2. thicker laminated veneer lumber assembly scheme:
Be followed successively by top layer, sandwich layer, bottom, bending resistance enhancement layer from top to bottom, the grain parallel of every layer of veneer is in plate length direction;
Top layer and bottom by 1 to 3 layer or inferior grade flood veneer and form;
Sandwich layer is made up of several inferior grade blanket glued veneers;
Bending resistance enhancement layer floods veneer by 1 floor height grade and forms;
F. hot pressing: to slab hot pressing under pressure 1.2-2.0MPa, release under Atmospheric temperature reaches about 95 DEG C conditions, then stacks cooling.
Above-mentioned production method, the veneer dynamic modulus of elasticity records with lossless detection method.Such as, record this veneer lumber density ρ and the transmission speed v of stress wave in this veneer, the dynamic modulus of elasticity is according to MOE=ρ v 2calculate.
Above-mentioned production method, according to the dynamic modulus of elasticity MOE often opening veneer, according to the dynamic modulus of elasticity MOE often opening veneer, draws the cumulative distribution function of veneer MOE; Be the MOE that particular value f between 10% to 90% is corresponding with veneer MOE cumulative distribution function fheight two grades are divided into veneer; Dynamic modulus of elasticity MOE>=MOE fveneer be high-grade veneer, dynamic modulus of elasticity MOE < MOE fveneer be inferior grade veneer; Or by similar approach, veneer is divided into high, medium and low Three Estate.Beneficial effect of the present invention:
Veneer is divided into high and low two grades or high, medium and low Three Estate according to the dynamic modulus of elasticity often opening veneer by the present invention, thus reduces the variability of wood single-plate elastic modelling quantity, finally greatly reduces the variability of properties of product; Utilize phenolic resin with two components impregnation fluid veneer, can realize resin portion penetrated wood inner, part stays wood surface as adhesive, avoids the second glue spreading to dipping veneer.The structure of plate slab carrying out assembly gained according to the different brackets of veneer improves bending resistance, the anti-wear performance of sheet material; Specifically, in laminated veneer lumber plate, because hardness after phenolic resin curing is high, water-tolerant, so dipping veneer is placed on plate surface can significantly strengthen sheet material bending resistance, surface abrasion resistance and dimensional stability; Top layer and bottom main purpose improve bending resistance and the scuff resistance of sheet material; Balance layer main purpose distributes sheet material load diatibution, improves the dimensional stability of laminated veneer lumber plate; In laminated veneer lumber, carry out flooding according to different brackets veneer or gluing process and assembly Optimal Structure Designing, increase bending resistance enhancement layer, inferior grade veneer can be made full use of and improve the bearing capacity of laminated veneer lumber.In a word, the present invention is directed to the reality that high-quality timber resources lacks, carry out flooding according to different brackets veneer or gluing process and assembly Optimal Structure Designing, and Reasonable adjustment processing parameter, realize the large use of small wood, the excellent use of bad material, can obtain the high-performance engineering laminated veneer lumber sheet material of the high low cost simultaneously of anti-bending strength, anti-wear performance and dimensional stability.
Accompanying drawing explanation
Fig. 1 is laminated veneer lumber (LVL) the assembly structural representation of embodiment 1.
Fig. 2 is the cumulative distribution function figure of pinus contorta veneer lumber density before veneer stress rating.
Fig. 3 is the cumulative distribution function figure of the pinus contorta veneer dynamic modulus of elasticity.
Fig. 4 is two kinds of grade veneer resin solid pickup cumulative distribution function figure.
Fig. 5 is laminated veneer lumber plate (LVB) the assembly structural representation of embodiment 2.
Fig. 6 is laminated veneer lumber plate (LVB) the assembly structural representation of embodiment 3.
Detailed description of the invention
Below in conjunction with embodiment, the present invention is further described in detail, but is not limited to this.
Embodiment 1: veneer grades and partial immersion produces laminated veneer lumber (LVL)
To the North America pinus contorta of import, obtain through rotary-cut the veneer that thickness is 3.2mm, and to be dried to moisture content be 3-6%.
Before veneer grades, the density p scope measuring veneer is 0.3g/cm 3to 0.6g/cm 3, the averag density ρ of all veneers is 0.473g/cm 3, standard deviation is 0.044g/cm 3, Fig. 2 is veneer lumber density cumulative distribution function before veneer grades.In Fig. 2, ordinate represents CDF(cumulative distribution function); Abscissa represents dry veneer lumber density, unit g/cm 3.
Measure the propagation time t of stress wave at veneer length direction according to each veneer length l veneer lumber density ρ with MOE=ρ v 2calculate the dynamic modulus of elasticity MOE of each veneer.The dynamic modulus of elasticity MOE of each veneer changes between 6897MPa to 16553MPa.Fig. 3 is the cumulative distribution function figure of the veneer dynamic modulus of elasticity.In Fig. 3, ordinate represents CDF(cumulative distribution function); Abscissa represents the veneer dynamic modulus of elasticity, units MPa.Grading to veneer according to the veneer dynamic modulus of elasticity, take 13311MPa as boundary (now particular value f=50%, MOE 50%) be divided into high-grade veneer E1 and inferior grade veneer E2 two parts (Fig. 3).After grading, veneer performance is in table 1.Can find out that in latter two veneer group of grading, density and elastic modelling quantity deviation all obviously diminish, and illustrate that two kinds of veneer performance variability all reduce.
Get part veneer to put into phenolic resin with two components maceration extract (molecular weight is the macromolecule phenolic resins of 1000-2000 and molecular weight is that the low molecule phenolic resins of 200-1000 is in proportion for 5:5 mixes, final phenolic resin with two components maceration extract solid content is 30%) middle dipping, wherein E1 grade veneer 5 minutes, E2 grade veneer 3 minutes, and at 50 DEG C of temperature dry 1-1.5 hour, make Veneer moisture reach 9-12%.Fig. 4 is two kinds of grade veneer resin solid pickup cumulative distribution function figure, can see that E2 grade veneer resin solid pickup is large, more easily flood.In Fig. 4, ordinate represents CDF(cumulative distribution function); Abscissa represents resin solid pickup, Veneer quality * 100% before resin solid pickup=(after dipping the front Veneer quality of Veneer quality-dipping) * maceration extract solid content/dipping.Do not flood veneer and be coated with the general commercial synvaren that solid content is 44%, glue-spread is 165g/m 2.
Veneer assemble pattern carries out according to shown in Fig. 1,1. surface structure: 2 layers of dipping E2 veneer 1,2, and its grain parallel is in plate length direction; 2. core structure: adopt and do not flood but gluing E2 grade veneer 3,4,5,6,7,8,9,10, its grain parallel is in plate length direction; 3. bottom: 2 layers of dipping E2 veneer 11,12, its grain parallel is in plate length direction; 4. bending resistance enhancement layer: 1 layer of E1 floods veneer 13(orlop), its grain parallel is in plate length direction.Slab after assembly at room temperature displays 30min.
Then slab is sent into hot pressing in hot press, heating platen temperature 155 DEG C, slab hot pressing pressure used is 1.4-1.6MPa, and hot pressing time is to guarantee that Atmospheric temperature reaches 95 DEG C and is as the criterion, then release.
The slab suppressed takes out from hot press, place 48 hours naturally cool, namely obtain the high-performance laminated veneer lumber that anti-bending strength, anti-wear performance and dimensional stability are high, namely by veneer grade and partial immersion produce laminated veneer lumber (LVL).Saw gained LVL test specimen processed, test performance, the results are shown in Table 2.
Comparative example 1: do not grade and do not flood the LVL of veneer production
Comparative example 1 is from the different of embodiment 1: do not grade to each veneer, also do not flood veneer, adopts 13 layers of blanket glued veneer to carry out assembly (other are with embodiment 1) during assembly.Other technique is identical with embodiment 1.Saw gained veneer processed not grade and do not flood LVL, test performance, the results are shown in Table 2.
In table 2, MOR refers to MOR; MOE refers to elastic modelling quantity, digitized representation standard deviation in ().As can be seen from Table 2, adopt the method for embodiment 1, veneer is through the LVL graded and partial immersion is produced, and its horizontal addload, Vertical loading bending property and shear strength are significantly improved than comparative example 1, and the deviation of each performance parameter obviously reduces.The water absorption rate of the 24h of embodiment 1 and thickness change, be obviously better than comparative example 1.Visible, the present invention utilizes the veneer of inferior grade wood producing to have anti-bending strength, anti-wear performance, dimensional stability advantage all preferably through the LVL graded and partial immersion is produced, and product can be widely used in large span carrying beam column and thicker packing case material etc.
Embodiment 2: the production of laminated veneer lumber plate (LVB) (veneer grades+top layer and each 2 veneers dipping of bottom)
Embodiment 2 is from the different of embodiment 1, and in embodiment 2, assembly structure is symmetrical structure, and specifically, top layer and bottom are respectively 2 floor height grade dipping E1 veneers 1,2,12,13;
Two balance layers of contiguous top layer and bottom are respectively 1 floor height grade dipping E1 veneer 3,11;
Sandwich layer is 7 inferior grade gluing E2 veneer 4-10; The grain direction of balance layer, perpendicular to other veneer grain direction, is shown in Fig. 5.Other technique is identical with embodiment 1.Saw gained laminated veneer lumber plate processed, test performance, the results are shown in Table 3.
Embodiment 3: the production of laminated veneer lumber plate (LVB) (veneer grades+top layer and each 1 veneer dipping of bottom)
Embodiment 3 is from the different of embodiment 1, and in embodiment 3, assembly structure is symmetrical structure, and specifically, top layer and bottom are respectively 1 floor height grade dipping E1 veneer 1,13;
Two balance layers of contiguous top layer and bottom are respectively 1 floor height grade dipping E1 veneer 2,12; Sandwich layer is 9 inferior grade gluing E2 veneer 3-11; The grain direction of balance layer, perpendicular to other veneer grain direction, is shown in Fig. 6.Other technique is identical with embodiment 1.Saw gained laminated veneer lumber plate processed, test performance, the results are shown in Table 3.
Comparative example 2: do not grade and do not flood the laminated veneer lumber plate (LVB) of veneer production
Comparative example 2 is from the different of embodiment 2: do not grade to each veneer, also do not flood veneer, adopts 13 layers of blanket glued veneer to carry out assembly during assembly.Other technique is identical with embodiment 2.Saw gained veneer processed not grade and do not flood LVB, test performance, the results are shown in Table 3.
In table 3, MOR refers to MOR; MOE refers to elastic modelling quantity, digitized representation standard deviation in ().As can be seen from Table 3, adopt the method for embodiment 2, veneer is through the LVB graded and partial immersion is produced, its bending property is all significantly improved than comparative example 2,24h water sucting thickness rate of change obviously reduces, and the deviation of each performance parameter obviously reduces, illustrate veneer grade after LVB performance variability reduce." veneer grades+top layer and bottom 2 dipping veneers " of embodiment 2 strengthens laminated veneer lumber plate benging performance and strengthens laminated veneer lumber plate higher than embodiment 3 " veneer grades+top layer and bottom 1 dipping veneer ".Visible, the present invention utilizes the veneer of inferior grade wood producing to have anti-bending strength, anti-wear performance, dimensional stability advantage all preferably through the LVB graded and partial immersion is produced, and product can extensive platform floor, building template and container bottom board etc.
The above embodiment of the present invention can not be used for limiting the present invention to explanation of the present invention, and any change in the implication suitable with claims of the present invention and scope, all should think to be included in the scope of claims.
The veneer that the present invention adopts inferior grade timber obtained is raw material, adopts stress wave to grade technology, according to the dynamic modulus of elasticity, veneer is divided into height two grades or high, normal, basic Three Estate, thus greatly reduces the variability of product; Utilize special phenolic resin with two components dipping veneer, resin portion penetrated wood can be realized inner, part stays wood surface as adhesive, avoid second glue spreading, simultaneously high, the water-tolerant of hardness after phenolic resin curing, dipping veneer is placed on plate surface and can significantly strengthens sheet material surface abrasion resistance and dimensional stability; Assembly Optimal Structure Designing is carried out according to different brackets veneer, and Reasonable adjustment processing parameter, realize the large use of small wood, the excellent use of bad material.Product can be widely used in all kinds of platform floor, the field such as building template and container bottom board, to alleviation timber supply and demand contradiction, realizes the excellent use of bad material, and increasing inferior grade wood utilization added value has very large realistic meaning.
The performance of table 1 two kinds of grade veneers
Table 2 laminated veneer lumber (LVL) physical and mechanical property
Note: it is parallel with glue-line that parallel boot refers to loading direction; It is vertical with glue-line that Vertical loading refers to loading direction.
Table 3 laminated veneer lumber plate (LVB) physical and mechanical property
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