阅读说明：本技术 一种竹材可饰面定向刨花板及其制备工艺 (Bamboo veneer oriented strand board and preparation process thereof ) 是由 张育栋 李宝明 侯海建 程远君 章生贵 于 2021-09-01 设计创作，主要内容包括：本发明提供了一种竹材可饰面定向刨花板及其制备工艺,涉及刨花板技术领域,以解决现有技术中可饰面定向刨花板的原料单一、易变形的技术问题。该刨花板包括芯层结构和设置在芯层结构两侧的上表层和下表层,芯层结构、上表层和下表层均由竹材原料制成,芯层结构由窄长刨花定向粘合而成,上表层和下表层由表层细料粘合而成,表层细料包括针状刨花、颗粒状刨花或木质纤维中的一种或两种或三种,由芯层结构至上表层和下表层的刨花呈现由大到小的渐变式铺装结构,使得制得的竹材定向可饰面刨花板的力学性能高、不变形,同时为刨花板增加了细料表面可用于饰面加工,扩大了其适用范围。(The invention provides a bamboo veneer-faced oriented strand board and a preparation process thereof, relates to the technical field of strand boards, and aims to solve the technical problems that in the prior art, the veneer-faced oriented strand board is single in raw material and easy to deform. This shaving board includes sandwich layer structure and sets up the top layer and the lower surface course in sandwich layer structure both sides, sandwich layer structure, top layer and lower surface course are made by the bamboo timber raw materials, sandwich layer structure is formed by the directional bonding of long and narrow wood shavings, top layer and lower surface course are formed by the bonding of top layer fines, the top layer fines include needle-like wood shavings, one or two kinds or three kinds in graininess wood shavings or the wood fibre, the wood shavings of the top layer and lower surface course appear by big formula of mating formation to little structure by sandwich layer structure, make the directional veneer shaving of bamboo timber that makes mechanical properties height, indeformable, it can be used to the veneer processing to have increased the fines surface simultaneously for the shaving board, its application scope has been enlarged.)

1. The utility model provides a but bamboo timber veneer oriented strand board, its characterized in that includes sandwich structure and sets up the upper epidermis and the lower surface course of sandwich structure both sides, sandwich structure the upper epidermis with the lower surface course is made by the bamboo timber raw materials, sandwich structure is formed by the directional bonding of narrow long wood shavings, the upper epidermis with the lower surface course is formed by the bonding of top layer fines, the top layer fines includes one or two kinds or three kinds in needle-like wood shavings, granular wood shavings or the wood fibre, by sandwich structure extremely the upper epidermis with the wood shavings on lower surface course present by big to little gradual change formula structure of mating formation.

2. The bamboo veneerable oriented strand board of claim 1, wherein the core structure comprises a middle core layer, an upper middle layer and a lower middle layer, the middle core layer is arranged between the upper middle layer and the lower middle layer, the upper middle layer is connected with the upper surface layer, the lower middle layer is connected with the lower surface layer, and the middle core layer, the upper middle layer and the lower middle layer are formed by oriented bonding of long and narrow wood shavings.

3. The bamboo veneerable oriented strand board of claim 2, wherein the upper skin layer, the upper intermediate layer, the intermediate core layer, the lower intermediate layer and the lower skin layer are joined by hot pressing.

4. The bamboo veneered oriented strand board as claimed in claim 2, wherein the wood shavings of the upper surface layer from the side close to the upper intermediate layer to the side far away from the upper intermediate layer and the wood shavings of the upper intermediate layer from the side close to the intermediate core layer to the side close to the upper surface layer are in a gradually-changing paving structure from large to small;

the lower surface layer is close to from one side of lower intermediate level to keeping away from the wood shavings of one side of lower intermediate level, the intermediate level is close to from one side of intermediate core layer to being close to from big to little wood shavings of one side of lower surface layer all is the gradual change formula structure of mating formation.

5. The bamboo veneerable oriented strand board of claim 2, wherein the upper surface layer and the lower surface layer are sized by a ring type glue blender, the upper middle layer and the lower middle layer are sized by a roller type glue blender, and the middle core layer is sized by another independent roller type glue blender; the upper surface layer go up the intermediate level middle sandwich layer down the intermediate level with lower surface layer is mated glue respectively after, paves through five shop's heads, its the intermediate level adopts transversely to pave, go up the intermediate level with the intermediate level is vertically paved down, the upper surface layer with the surface layer is paved for the air current down, obtains the slab of five-layer structure.

6. A process for preparing bamboo veneered oriented strand board, which is based on the bamboo veneered oriented strand board of any one of claims 2-5, and mainly comprises the following steps:

step S1, preparing wood shavings: preparing wood shavings by taking bamboo as a raw material, and then sending the wood shavings into a wet storage bin for storage;

step S2, drying wood shavings: continuously drying the wood shavings by using a dryer to ensure that the absolute water content of the dried wood shavings is 2.5-6%;

step S3, screening wood shavings: screening the dried wood shavings by using a roller disc screen, wherein the screened material is divided into first type wood shavings, second type wood shavings and third type wood shavings with different sizes, the first type wood shavings are adopted in the middle core layer, the second type wood shavings are adopted in the upper middle layer and the lower middle layer, and the third type wood shavings are adopted in the upper surface layer and the lower surface layer;

step S4, wood shaving and polishing: grinding the third wood shavings in the step S3 by using a pulse type airflow crusher, and enabling the third wood shavings to enter a grinding machine and then to collide and rub with each other under the driving of airflow rotating at a high speed, so that the wood shavings are torn into bamboo fibers;

step S5, glue mixing: feeding the dried first wood shavings and the dried second wood shavings into a roller type glue mixer for glue applying process, and mixing the third wood shavings with glue by a ring type glue mixer;

step S6, wood shaving and paving: the bamboo oriented strand board capable of facing the bamboo is paved by adopting a five-layer paving process, and a lower surface layer, a lower middle layer, a middle core layer, an upper middle layer and an upper surface layer are sequentially arranged along the running direction of the paving belt;

step S7, hot pressing: the paved plate enters a continuous flat-pressing hot press for hot press molding;

step S8, cutting: and sawing the hot-pressed plate into the specification and size by a flush saw and a cross cut saw in sequence.

7. The process of claim 6, wherein the wood shavings preparation in step S1 are processed by a transverse wood pulling machine, a longitudinal lifting machine, a bundling machine and a disc type long wood shavings system; the bamboo materials damaged on the outer wall can be moved and extruded by a telescopic side plate on one side of the bundling machine after being regulated by the bundling machine to generate crushing, and the crushed bamboo strips are pressed by the disc type long material slicing system and then pushed into the disc type long material slicing machine; the disc type long material chipping machine can cut longitudinally arranged bamboo strips into wood shavings through the lateral movement of a cutter head of the disc type long material chipping machine.

8. The process of claim 6, wherein the drying step S2 is carried out by a single-pass roller dryer or a low-temperature belt dryer; in step S3, the first type of wood shavings used in the middle core layer have a length of 80-120mm and a width of 30-50mm, the second type of wood shavings used in the upper middle layer and the lower middle layer have a length of 40-80mm and a width of 20-35mm, and the third type of wood shavings used in the upper surface layer and the lower surface layer have a length of less than 40 mm.

9. The process of claim 6, wherein the glue used in step S5 is thermosetting phenolic resin, and the amount of wood chips applied to the intermediate core layer is 60-80kg/m³The wood shaving glue application amount of the upper middle layer and the lower middle layer is 70-90kg/m³The glue application amount of the wood shavings of the upper surface layer and the lower surface layer is 80-100kg/m³Wherein the solid content of the phenolic resin is 55 +/-2%.

10. The process of claim 6, wherein in step S6, the upper surface layer and the lower surface layer are laid by an air-flow laying machine, the upper intermediate layer and the lower intermediate layer are laid by a disc-type directional laying machine, and the intermediate core layer is laid by a groove-type directional laying machine.

Technical Field

The invention relates to the technical field of shaving boards, in particular to a bamboo veneer oriented shaving board and a preparation process thereof.

Background

The oriented structure shaving board is a kind of artificial board made up by using small-diameter wood, intermediate cut wood, wood core, board skin and branch wood as raw material, making them pass through the processes of special-purpose equipment to make them into the shavings whose length is 40mm-70mm, width is 5mm-20mm and thickness is 0.3mm-0.7mm, drying, gluing and special-purpose equipment to make the shavings of surface core layer be crisscrossed and oriented and laid, and hot-pressed and formed. The wood shaving board is formed by directionally paving the narrow and long large shaving units and then hot pressing, so that the wood shaving board has the advantages of high bending strength, small linear expansion coefficient, good dimensional stability, strong nail holding force, easiness in surface decoration and the like, and is widely applied to the industries of packaging, building, vehicle and ship manufacturing and the like.

In recent years, the veneered oriented strand board is used as a novel board, wherein the upper surface and the lower surface of a three-layer or multi-layer oriented strand board blank are additionally provided with fine material layers, so that the application field of the oriented strand board is enlarged, and compared with the common strand board, the veneered oriented strand board has higher mechanical strength and screw holding force, thereby being used as an upgrading product of the common strand board and being widely used for indoor decoration and household products. Is gradually accepted and used by wide consumers in China, and the annual output is 20 ten thousand meters³The continuous flat pressing production line is also a blowout type outburst in China, and the directional planing is carried out in the end of 2020The annual capacity of the flower plate breaks through 500 ten thousand meters³. However, raw wood with a diameter of 8cm to 35cm is generally required as a raw material for producing oriented strand board; as one of the countries with relatively deficient wood resources, the supply of the logs is a big gap.

Generally, in a continuous flat pressing production line, because of its large production capacity and large demand for shavings, large-diameter logs are usually processed by a rotary cutter, a disc type long material machine, a drum type long material machine, a ring type long material machine, etc. to meet the production requirements.

Disclosure of Invention

In view of the above, the invention aims to provide a bamboo veneer oriented strand board and a preparation process thereof, so as to solve the technical problems that the oriented strand board in the prior art is single in raw material and easy to deform.

In order to achieve the purpose, the invention provides a bamboo veneerable oriented strand board which comprises a core layer structure, an upper surface layer and a lower surface layer, wherein the upper surface layer and the lower surface layer are arranged on two sides of the core layer structure, the upper surface layer and the lower surface layer are all made of bamboo raw materials, the core layer structure is formed by directionally bonding narrow and long wood shavings, the upper surface layer and the lower surface layer are formed by bonding surface layer fine materials, the surface layer fine materials comprise one or two or three of needle-shaped wood shavings, granular wood shavings or wood fibers, and the wood shavings from the core layer structure to the upper surface layer and the lower surface layer are in a gradually-changing paving structure from large to small.

Preferably, the core layer structure comprises a middle core layer, an upper middle layer and a lower middle layer, the middle core layer is arranged between the upper middle layer and the lower middle layer, the upper middle layer is connected with the upper surface layer, the lower middle layer is connected with the lower surface layer, and the middle core layer, the upper middle layer and the lower middle layer are formed by directionally bonding narrow and long wood shavings.

Preferably, the upper surface layer, the upper intermediate layer, the intermediate core layer, the lower intermediate layer and the lower surface layer are connected by hot pressing.

Preferably, the wood shavings of the upper surface layer from the side close to the upper middle layer to the side far away from the upper middle layer and the wood shavings of the upper middle layer from the side close to the middle core layer to the side close to the upper surface layer are in a gradually-changing paving structure from large to small;

the lower surface layer is close to from one side of lower intermediate level to keeping away from the wood shavings of one side of lower intermediate level, the intermediate level is close to from one side of intermediate core layer to being close to from big to little wood shavings of one side of lower surface layer all is the gradual change formula structure of mating formation.

Preferably, the upper surface layer and the lower surface layer are sized by a ring-type glue blender, the upper middle layer and the lower middle layer are sized by a roller-type glue blender, and the middle core layer is sized by another independent roller-type glue blender; the upper surface layer go up the intermediate level middle sandwich layer down the intermediate level with lower surface layer is mated glue respectively after, paves through five shop's heads, its the intermediate level adopts transversely to pave, go up the intermediate level with the intermediate level is vertically paved down, the upper surface layer with the surface layer is paved for the air current down, obtains the slab of five-layer structure.

The preparation process of the veneered oriented strand board is characterized in that the preparation process mainly comprises the following steps based on the bamboo veneered oriented strand board:

step S1, preparing wood shavings: preparing wood shavings by taking bamboo as a raw material, and then sending the wood shavings into a wet storage bin for storage;

step S2, drying wood shavings: continuously drying the wood shavings by using a dryer to ensure that the absolute water content of the dried wood shavings is 2.5-6%;

step S3, screening wood shavings: screening the dried wood shavings by using a roller disc screen, wherein the screened material is divided into first type wood shavings, second type wood shavings and third type wood shavings with different sizes, the first type wood shavings are adopted in the middle core layer, the second type wood shavings are adopted in the upper middle layer and the lower middle layer, and the third type wood shavings are adopted in the upper surface layer and the lower surface layer;

step S4, wood shaving and polishing: grinding the third wood shavings in the step S3 by using a pulse type airflow crusher, and enabling the third wood shavings to enter a grinding machine and then to collide and rub with each other under the driving of airflow rotating at a high speed, so that the wood shavings are torn into bamboo fibers;

step S5, glue mixing: feeding the dried first wood shavings and the dried second wood shavings into a roller type glue mixer for glue applying process, and mixing the third wood shavings with glue by a ring type glue mixer;

step S6, wood shaving and paving: the bamboo oriented strand board capable of facing the bamboo is paved by adopting a five-layer paving process, and a lower surface layer, a lower middle layer, a middle core layer, an upper middle layer and an upper surface layer are sequentially arranged along the running direction of the paving belt;

step S7, hot pressing: the paved plate enters a continuous flat-pressing hot press for hot press molding;

step S8, cutting: and sawing the hot-pressed plate into the specification and size by a flush saw and a cross cut saw in sequence.

Preferably, the preparation of the wood shavings in the step S1 is completed by a transverse wood pulling machine, a longitudinal lifting machine, a bundling machine and a disc type long wood shaving system; the bamboo materials damaged on the outer wall can be moved and extruded by a telescopic side plate on one side of the bundling machine after being regulated by the bundling machine to generate crushing, and the crushed bamboo strips are pressed by the disc type long material slicing system and then pushed into the disc type long material slicing machine; the disc type long material chipping machine can cut longitudinally arranged bamboo strips into wood shavings through the lateral movement of a cutter head of the disc type long material chipping machine.

Preferably, the drying is performed in step S2 by using a single-pass drum dryer or a low-temperature belt dryer;

in step S3, the first type of wood shavings used in the middle core layer have a length of 80-120mm and a width of 30-50mm, the second type of wood shavings used in the upper middle layer and the lower middle layer have a length of 40-80mm and a width of 20-35mm, and the third type of wood shavings used in the upper surface layer and the lower surface layer have a length of less than 40 mm.

Preferably, the size is mixed in step S5The glue is thermosetting phenolic resin, and the wood shaving glue applying amount of the middle core layer is 60-80kg/m³The wood shaving glue application amount of the upper middle layer and the lower middle layer is 70-90kg/m³The glue application amount of the wood shavings of the upper surface layer and the lower surface layer is 80-100kg/m³Wherein the solid content of the phenolic resin is 55 +/-2%.

Preferably, in step S6, the upper surface layer and the lower surface layer are paved by an air flow paving machine, the upper intermediate layer and the lower intermediate layer are paved by a disc type directional paving machine, and the intermediate core layer is paved by a groove type directional paving machine.

The bamboo veneerable oriented strand board provided by the invention comprises a core layer structure, and an upper surface layer and a lower surface layer which are arranged on two sides of the core layer structure, firstly, in the aspect of selecting raw materials, the core layer structure, the upper surface layer and the lower surface layer all adopt bamboo as the raw materials, the bamboo grows fast, the yield is high, the bamboo cutting amount in China is about 500 million tons every year, and the bamboo can be formed in about 5-10 years; in addition, the physical and mechanical properties of the bamboo wood-based panel, such as static bending strength, elastic modulus, dimensional stability and the like, are far better than those of a common wood-based panel. Secondly, in the aspect of the treatment of the wood shavings, an advanced pulse type airflow crusher is adopted, the prepared fine materials are fibrous and are used for processing veneers (an upper surface layer and a lower surface layer), the core layer structure is formed by directionally bonding narrow and long wood shavings, and the wood shavings from the core layer structure to the upper surface layer and the lower surface layer are in a gradually-changing paving structure from large to small, so that the prepared shaving board is high in mechanical property and free of deformation, meanwhile, the fine material surface is added for the shaving board and can be used for processing the veneers, and the application range of the shaving board is expanded.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a schematic structural view of a faceable oriented strand board provided by an embodiment of the present invention;

fig. 2 is a flow chart of a process for preparing a veneered oriented strand board according to an embodiment of the invention.

Reference numerals: 1. a lower surface layer; 2. a lower intermediate layer; 3. an intermediate core layer; 4. an upper intermediate layer; 5. and (4) an upper surface layer.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the technical solutions of the present invention will be described in detail below. It is to be understood that the described embodiments are merely exemplary of the invention, and not restrictive of the full scope of the invention. All other embodiments, which can be derived by a person skilled in the art from the examples given herein without any inventive step, are within the scope of the present invention.

In the description of the present invention, it is to be noted that, unless otherwise specified, "a plurality" means two or more; the terms "upper", "lower", "left", "right", "inner", "outer", "front", "rear", "head", "tail", and the like, indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, are only for convenience in describing and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed in a particular orientation, and be operated, and thus, should not be construed as limiting the invention. Furthermore, the terms "first," "second," "third," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present invention, it should also be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; may be directly connected or indirectly connected through an intermediate. The specific meaning of the above terms in the present invention can be understood as appropriate to those of ordinary skill in the art.

Referring to fig. 1, the invention provides a bamboo veneered oriented strand board, which comprises a core layer structure, an upper surface layer 5 and a lower surface layer 1, wherein the upper surface layer 5 and the lower surface layer 1 are arranged on two sides of the core layer structure, the upper surface layer 5 and the lower surface layer 1 are all made of bamboo raw materials, bamboos grow fast and are high in yield, the bamboo cutting amount of China is about 500 ten thousand tons every year, and the oriented strand board can be obtained in about 5-10 years; in addition, the physical and mechanical properties of the bamboo wood-based panel, such as static bending strength, elastic modulus, dimensional stability and the like, are far better than those of a common wood-based panel. The core layer structure is formed by directionally bonding narrow and long wood shavings, the upper surface layer 5 and the lower surface layer 1 are formed by bonding surface layer fine materials, the surface layer fine materials comprise one or two or three of needle-shaped wood shavings, granular wood shavings or wood fibers, and the wood shavings from the core layer structure to the upper surface layer 5 and the lower surface layer 1 are of a gradually-changing pavement structure from large to small.

In this embodiment, the sandwich layer structure includes middle sandwich layer 3, upper intermediate layer 4 and lower intermediate layer 2, and middle sandwich layer 3 sets up between upper intermediate layer 4 and lower intermediate layer 2, and upper intermediate layer 4, middle sandwich layer 3 and lower intermediate layer 2 superpose mutually and set up to upper intermediate layer 4 is connected with upper surface layer 5, and lower intermediate layer 2 is connected with lower surface layer 1, and middle sandwich layer 3, upper intermediate layer 4 and lower intermediate layer 2 are formed by the directional bonding of long and narrow wood shavings. Like this, sandwich layer structure divide into middle sandwich layer 3, go up intermediate level 4 and lower intermediate level 2, is favorable to mating formation, does benefit to the symmetry of guaranteeing this oriented strand board, has improved the intensity of this shaving board, makes this shaving board be difficult for warping.

The upper surface layer 5, the upper intermediate layer 4, the intermediate core layer 3, the lower intermediate layer 2 and the lower surface layer 1 are connected by means of hot pressing. In this way, the joint strength between the upper skin layer 5, the upper intermediate layer 4, the intermediate core layer 3, the lower intermediate layer 2, and the lower skin layer 1 is ensured.

In the preferred scheme of this embodiment, the wood shavings of the upper surface layer 5 from the side close to the upper intermediate layer 4 to the side far from the upper intermediate layer 4 and the wood shavings of the upper intermediate layer 4 from the side close to the intermediate core layer 3 to the side close to the upper surface layer 5 are all in a gradually-changing paving structure from large to small; the lower surface layer 1 is a gradually-changing paving structure from large to small from the side close to the lower middle layer 2 to the wood shavings far away from the lower middle layer 2, and the lower middle layer 2 is a gradually-changing paving structure from the side close to the middle core layer 3 to the side close to the lower surface layer 1.

The invention also provides a preparation process of the veneered oriented strand board, which mainly comprises the following steps as shown in figure 2:

step S1, preparing wood shavings: the wood preparation working section mainly comprises a transverse wood pulling machine, a longitudinal lifting machine, a bundling machine and a disc type long wood shaving system; a middle dividing saw is arranged in the middle of the transverse wood drawing machine and is used for sawing bamboo materials with different lengths; the longitudinal lifter is provided with a plurality of groups of rotating rollers respectively at the upper and lower parts in the longitudinal lifting and conveying process of the bamboo wood, the roller is provided with spaced nicking knife sets, the outer wall of the bamboo wood is longitudinally cut through the spaced nicking knives, the transverse interval between the nicking knife sets can be adjusted within the range of 10mm-40mm, the interval is the width of the wood shavings, the outer wall of the bamboo wood is scratched by the nicking knives, and the bamboo wood cannot be immediately broken due to the transverse wood joint interval between the two bamboo joints, so that the complete structure of the bamboo wood is still maintained; the bundling machine is used for continuously and regularly breaking the wall of the bamboo wood, the bundled bamboo wood is extruded through the movement of the telescopic side plate with the heavy compression type arranged on one side of the bundling machine, and the extruded bamboo strips are crushed into bamboo strips which are longitudinally arranged along the nicking knife at intervals.

The crushed bamboo strips are pressed by a presser of a disc type long material slicing system and then pushed into a disc type long material chipper through a material pusher at the rear end; the disc type long material chipping machine cuts the bamboo strips which are longitudinally arranged into the required first type of shavings by the lateral movement of the cutter head, the length of the shavings is determined by a scoring cutter which is arranged in the diameter direction of the cutter head, and the length of the shavings can be adjusted between 50mm and 120 mm; the thickness of the wood shavings is controlled by the extension amount and the feeding speed of a fly cutter of the long wood chipper, and can be uniformly controlled between 0.2 mm and 0.6 mm; because the cutter head and the bamboo strips of the disc type long wood flaker are arranged in parallel and cut, the disc type long wood flaker can obtain regular bamboo shavings with the maximum efficiency, the defect of thin and hollow bamboo wall is overcome, and the yield of the bamboo shavings is improved.

In addition, in the process of slicing the long bamboo materials, the slicing effect of the disc type long material slicing machine is optimal; of course, drum type log flakers may also be used.

Step S2, drying wood shavings: continuously drying the wood shavings by using a dryer to ensure that the absolute water content of the dried wood shavings is 2.5-6%; the process can be dried by a single-channel roller dryer and also can be dried by a low-temperature belt dryer, the damage rate of the first type of wood shavings is less, and the drying quality of the wood shavings is improved.

Step S3, screening wood shavings: screening the dried wood shavings by using a roller disc screen, wherein the screened material is divided into first type wood shavings, second type wood shavings and third type wood shavings with different sizes, the first type wood shavings are adopted as the middle core layer 3, the second type wood shavings are adopted as the upper middle layer 4 and the lower middle layer 2, and the third type wood shavings are adopted as the upper surface layer 5 and the lower surface layer 1;

the length of the first type of wood shavings adopted by the middle core layer 3 is 80-120mm, the width of the first type of wood shavings is 30-50mm, the length of the second type of wood shavings adopted by the upper middle layer 4 and the lower middle layer 2 is 40-80mm, the width of the second type of wood shavings is 20-35mm, the length of the third type of wood shavings adopted by the upper surface layer 5 and the lower surface layer 1 is less than 40mm, the wood shavings can be used as the fabrics of the upper surface layer 5 and the lower surface layer 1 of the veneered bamboo wood oriented strand board after being screened and polished again, and the proportion of the middle and small wood shavings (the second type of wood shavings and the third type of wood shavings) can be adjusted to supplement when the fabrics are insufficient.

Step S4, wood shaving and polishing: adopt pulsed air current breaker to polish the third type of wood shavings in step S3, there is not cutting tool in the middle of the pulsed air current breaker, and small-size bamboo timber wood shavings (third type of wood shavings) get into pulsed air current breaker after under the high-speed rotatory air current drives, collision friction each other to tear third type of wood shavings into the bamboo timber fibre, greatly reduced ordinary breaker mechanical nature polish the fibrous damage of bamboo timber, thereby improved the quiet bending strength and the elastic modulus of panel. The diameter of the qualified fine material after being polished is determined by the aperture of the screen mesh on the outer wall of the crusher, and the aperture of the screen mesh is 0.8-1.2 mm.

Step S5, glue mixing: through screening and polishing, the raw materials of the bamboo veneer oriented strand board are divided into large wood shavings of the core layer, large wood shavings in the upper and lower middle layers 2 and small wood shavings serving as fine materials on the upper and lower surfaces. The core layer, the upper and the lower intermediate layers 2 are long and narrow large shavings, so a drum-type glue mixer can be adopted for high-speed glue mixing; the fine small wood shavings adopted by the upper and lower surface layers 1 need to be mixed by a ring-type glue mixer used for common shaving boards.

The glue is thermosetting phenolic resin, and the glue applying amount of core layer wood shavings is 60-80kg/m³The wood shaving glue application amount of the upper middle layer 4 and the lower middle layer 2 is 70-90kg/m³The glue application amount of the wood shavings of the upper surface layer 5 and the lower surface layer 1 is 80-100kg/m³Wherein the solid content of the phenolic resin is 55 +/-2%. As the bamboo fibers have better waterproof performance, the large wood shavings of the middle three layers (the middle core layer 3, the upper middle layer 4 and the lower middle layer 2) can be free from adding any waterproof agent, and the fine wood shavings of the upper surface layer 5 and the lower surface layer 1 have larger fiber specific surface area, so that the corresponding standard requirements of the plate can be met only by adding a certain amount of waterproof agent except for increased glue application amount, and when the paraffin is adopted as the waterproof agent, the addition amount is 6-10kg/m³When emulsified paraffin is used, the addition amount is 4-8kg/m³。

Step S6, wood shaving and paving: the bamboo oriented strand board capable of facing is paved by adopting a five-layer paving process, and a lower surface layer 1, a lower middle layer 2, a middle core layer 3, an upper middle layer 4 and an upper surface layer 5 are sequentially arranged along the running direction of the paving belt. The upper surface layer 5, the upper middle layer 4, the middle core layer 3, the lower middle layer 2 and the lower surface layer 1 are paved by five paving heads after being respectively glued.

The upper surface layer 5 and the lower surface layer 1 are paved on the surface layer by an air flow paving machine, the first paving machine is paved on the lower surface, the moving direction of a paving head of the first paving machine is opposite to that of a paving belt, and the direction of the paving head is forward; the fifth paving machine paves the upper surface, and the paving head of the fifth paving machine is in the same direction as the movement direction of the paving belt and faces backwards; the pavement of the upper surface layer 5 and the lower surface layer 1 can be in a gradual structure, and the surface is more exquisite, thereby being beneficial to the processing of the veneer.

The upper middle layer 4 and the lower middle layer 2 are paved as middle layers by a disc type directional paving machine, the lower middle layer 2 is paved by a second paving machine, and the paving head of the second paving machine is in the same direction as the movement direction of a paving belt and faces backwards; the fourth spreading machine spreads the upper middle layer 4, and the moving direction of the spreading head of the fourth spreading machine is opposite to that of the spreading belt, and the direction of the spreading head is forward. The intermediate layer shavings thus laid are arranged longitudinally on the laying belt.

The middle core layer 3 is paved by a groove type directional paving machine, the installation direction of the groove type paving machine can be forward or backward, and the paved wood shavings are transversely distributed on the paving belt.

Step S7, hot pressing: the paved plate enters a continuous flat-pressing hot press for hot press molding; the hot pressing temperature is 175-240 ℃, the pressure is 0.2-3.5Mpa, and the hot pressing factor is 8-12 s/mm.

Step S8, cutting: the hot-pressed plate is sawed into specification sizes by a flush saw and a cross cutting saw in sequence; after the cultivation, the surface is sanded, and the sanding allowance of the upper surface and the lower surface is 0.5-0.8 mm.

The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present invention, and the changes or substitutions should be covered within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.