METHOD FOR QUICK HOT-PRESS FORMING OF LAMINATED WOOD

Abstract

The present invention discloses a method for quick hot-press forming of laminated wood. The method includes: drying a machined small wood material to a moisture content of 5-8 wt %; gluing the dried small wood material, and assembling and laying the dried small wood material to be a square material or a sheet material, where an adhesive for the gluing is a water-soluble adhesive having a solid content of 45-60 wt %; clamping the square material or the sheet material through a three-dimensional metal clamp; sending the clamped square material or sheet material together with the clamp into a microwave heating machine for microwave heating to obtain a formed laminated wood, where the time from the gluing to the entry into the microwave heating machine is controlled to not exceed 15 min. According to the present invention, a glued part that needs to be heated can be heated quickly, precisely and effectively, the gluing strength and production efficiency of the laminated wood can be significantly improved, and the cost of production energy consumption is reduced.

Claims

1. A method for quick hot-press forming of laminated wood, comprising the following steps: step S1: drying a machined small wood material to a moisture content of 5-8 wt %; step s2: gluing the dried small wood material, and assembling and laying the dried small wood material to be a square material or a sheet material, wherein an adhesive for the gluing is a water-soluble adhesive having a solid content of 45-60 wt %; step S3: clamping the square material or the sheet material through a three-dimensional metal clamp; and step S4: sending the clamped square material or sheet material together with the clamp into a microwave heating machine for microwave heating to obtain a formed laminated wood, wherein the time from the gluing to the entry into the microwave heating machine is controlled to not exceed 15 min.

2. The method for quick hot-press forming of laminated wood according to claim 1, wherein the gluing in step S2 uses a urea-formaldehyde resin adhesive.

3. The method for quick hot-press forming of laminated wood according to claim 1, wherein the amount of the adhesive applied in step S2 is 150-360 g/m.sup.2.

4. The method for quick hot-press forming of laminated wood according to claim 2, wherein the amount of the adhesive applied in step S2 is 150-360 g/m.sup.2.

5. The method for quick hot-press forming of laminated wood according to claim 1, wherein a clamping force of the clamp in step S3 is 1.0-2.5 MPa.

6. The method for quick hot-press forming of laminated wood according to claim 2, wherein a clamping force of the clamp in step S3 is 1.0-2.5 MPa.

7. The method for quick hot-press forming of laminated wood according to claim 1, wherein the microwave heating operating temperature in step S4 is 100-200 C.

8. The method for quick hot-press forming of laminated wood according to claim 1, wherein the microwave heating microwave frequency in step S4 is 1.5-2.5 GHz.

9. The method for quick hot-press forming of laminated wood according to claim 7, wherein the microwave heating microwave frequency in step S4 is 1.5-2.5 GHz.

10. The method for quick hot-press forming of laminated wood according to claim 1, wherein the time from the square material or sheet material entry into the microwave heating machine to the leaving from the microwave heating machine in step S4 is 5-10 min.

11. The method for quick hot-press forming of laminated wood according to claim 7, wherein the time from the square material or sheet material entry into the microwave heating machine to the leaving from the microwave heating machine in step S4 is 5-10 min.

Description

DETAILED DESCRIPTION OF EMBODIMENTS

[0025] In order to facilitate the understanding of the present invention, the present invention will be described more fully and in detail below with reference to the preferred embodiments, but the protection scope of the present invention is not limited to the following specific embodiments.

[0026] Unless otherwise defined, all technical terms used hereinafter have the same meaning as commonly understood by those skilled in the art. The technical terms used herein are for the purpose of describing specific embodiments, and are not intended to limit the protection scope of the present invention.

[0027] Unless otherwise specified, the reagents, equipment, and the like used in the present invention are commercially available or can be prepared by an existing method.

[0028] A method for quick hot-press forming of laminated wood according to an embodiment of the present invention includes the following steps:

[0029] Step 1: send a machined small wood material into an ordinary wood drying kiln for drying to a moisture content of 5-8 wt %.

[0030] Step 2: prepare an adhesive, adopt a water-soluble adhesive, and the solid content of the adhesive is required to be 45-60 wt %. In a specific embodiment, a urea-formaldehyde resin adhesive is used.

[0031] Step 3: lay the dried small wood material into a square material or a sheet material with a certain specification according to a gluing and assembly process in the process of production of ordinary laminated wood, where the amount of glue applied is 150-360 g/m.sup.2.

[0032] Step 4: clamp the laid square material or sheet material with a certain specification through a three-dimensional metal clamp, where a clamping force is 1.0-2.5 MPa.

[0033] Step 5: send the clamped square material or sheet material together with the clamp into a microwave heating machine.

[0034] A main body of the microwave heating machine has a box type structure, and a lower portion of the box type structure is provided with a roller conveyor. The roller conveyor in the heating machine is responsible for transporting the clamped square material or sheet material together with the clamp into the microwave heating machine from one end of the wood microwave heating machine, and transporting the clamped square material or sheet material together with the clamp out from the other end. An operating temperature is 100-200 C., and a microwave frequency is 1.5-2.5 GHz.

[0035] In order to prevent moisture in the adhesive from massively permeating into the interior of the wood and affecting the heating and temperature of a glued part during microwave heating, it is required that the time from the gluing to the entry into the microwave heating machine does not exceed 15 min. If the time exceeds 15 min, the moisture in the adhesive will permeate into the wood too much, resulting in a decrease in the moisture content of the glued part and a decrease in the hot pressing effect.

[0036] The time from the entry into the microwave heating machine to the leaving from the microwave heating machine is generally 5-10 min. If the heating time is too long, the glued part is carbonized; if the heating time is too short, the temperature is too low, the curing rate of the adhesive is lowered, and the gluing strength is affected.

[0037] Step 6: take out the hot-pressed square material or sheet material to obtain a formed laminated wood with a certain specification and stack the laminated wood for storage.

[0038] Details will be described below by way of embodiments and reference examples.

Embodiment 1

[0039] Step 1: send a machined small wood material (poplar) into an ordinary wood drying kiln for drying to a moisture content of 5%.

[0040] Step 2: prepare a urea-formaldehyde resin adhesive having a solid content of 50%.

[0041] Step 3: lay the dried small wood material into a square material or a sheet material with a certain specification according to a gluing and assembly process in the process of production of ordinary laminated wood, where the amount of glue applied is 220 g/m.sup.2.

[0042] Step 4: clamp the laid square material or sheet material with a certain specification through a three-dimensional metal clamp, where a clamping force is 2.5 MPa.

[0043] Step 5: send the clamped square material or sheet material together with the clamp into a wood microwave heating machine, where the heating time is 8 min, a heating temperature is 130 C., and a microwave frequency is 1.8 GHz.

[0044] Step 6: take out the hot-pressed square material or sheet material to obtain a formed laminated wood with a certain specification and stack the laminated wood for storage.

[0045] Compared with an ordinary hot-press forming technology, the method improves the forming efficiency by 190%. The strength comparison is shown in the following table.

TABLE-US-00001 Static Elasticity Shear bending modulus strength intensity (MPa) (MPa) (MPa) Common laminated wood 62.4 8100 3.1 of poplar Laminated wood of poplar 85.7 10400 4.3 in this embodiment

Embodiment 2

[0046] Step 1: send a machined small wood material (eucalyptus) into an ordinary wood drying kiln for drying to a moisture content of 6%.

[0047] Step 2: prepare a urea-formaldehyde resin adhesive having a solid content of 45%.

[0048] Step 3: lay the dried small wood material into a square material or a sheet material with a certain specification according to a gluing and assembly process in the process of production of ordinary laminated wood, where the amount of glue applied is 190 g/m.sup.2.

[0049] Step 4: clamp the laid square material or sheet material with a certain specification through a three-dimensional metal clamp, where a clamping force is 2.0 MPa.

[0050] Step 5: send the clamped square material or sheet material together with the clamp into a wood microwave heating machine, where the heating time is 6 min, a hot-pressing temperature is 150 , and a microwave frequency is 2.0 GHz.

[0051] Step 6: take out the hot-pressed square material or sheet material to obtain a formed laminated wood with a certain specification and stack the laminated wood for storage.

[0052] Compared with an ordinary hot-press forming technology, the method improves the forming efficiency by 240%. The strength comparison is shown in the following table.

TABLE-US-00002 Static Elasticity Shear bending modulus strength intensity (MPa) (MPa) (MPa) Common laminated wood 61.5 8000 3.2 of eucalyptus Laminated wood of 86.0 11100 4.5 eucalyptus in this embodiment

Embodiment 3

[0053] Step 1: send a machined small wood material (pine) into an ordinary wood drying kiln for drying to a moisture content of 8%.

[0054] Step 2: prepare a urea-formaldehyde resin adhesive having a solid content of 60%.

[0055] Step 3: lay the dried small wood material into a square material or a sheet material with a certain specification according to a gluing and assembly process in the process of production of ordinary laminated wood, where the amount of glue applied is 250 g/m.sup.2.

[0056] Step 4: clamp the laid square material or sheet material with a certain specification through a three-dimensional metal clamp, where a clamping force is 1.5 MPa.

[0057] Step 5: send the clamped square material or sheet material together with the clamp into a wood microwave heating machine, where the heating time is 5 min, a hot-pressing temperature is 180, and a microwave frequency is 2.5 GHz.

[0058] Step 6: take out the heated square material or sheet material to obtain a formed laminated wood with a certain specification and stack the laminated wood for storage.

[0059] Compared with an ordinary hot-press forming technology, the method improves the forming efficiency by 260%. The strength comparison is shown in the following table.

TABLE-US-00003 Static Elasticity Shear bending modulus strength intensity (MPa) (MPa) (MPa) Common laminated wood of 60.7 7980 3.0 pine Laminated wood of pine in this 83.5 10200 4.3 embodiment

[0060] The above are only preferred embodiments of the present invention and are not intended to limit the present invention in any way. Therefore, any simple modifications and equivalent changes to the above embodiments in accordance with the technical essence of the present invention without departing from the contents of the technical solutions of the present invention should fall within the protection scope of the technical solutions of the present invention.