CN111906885A

CN111906885A - Ultrahigh-density anti-bending and anti-doubling plate and production method thereof

Info

Publication number: CN111906885A
Application number: CN202010794191.9A
Authority: CN
Inventors: 李茂桧
Original assignee: Jinan Caiming Industrial Co ltd
Current assignee: Jinan Caiming Industrial Co ltd
Priority date: 2020-08-10
Filing date: 2020-08-10
Publication date: 2020-11-10

Abstract

The invention belongs to the technical field of anti-doubling board production, and particularly relates to an ultrahigh-density anti-bending anti-doubling board and a production method thereof, wherein the anti-doubling board is a wood pulp anti-doubling board, and the density of the wood pulp anti-doubling board is 1200-1500kg/m³The static bending strength is more than or equal to 60 MPa; the method for producing the ultra-high density bending-resistant anti-doubling plate is used for producing the anti-doubling plate, and the product has high density, high static bending strength and low water absorption expansion rate.

Description

Ultrahigh-density anti-bending and anti-doubling plate and production method thereof

Technical Field

The invention belongs to the technical field of anti-doubling plate production, and particularly relates to an ultrahigh-density anti-bending anti-doubling plate and a production method thereof.

Background

The common wood pulp compact board is generally produced by adopting a continuous hot press, the board after hot pressing enters the processes of curing, sanding and cutting, and the density of the wood pulp compact board produced by the continuous hot press is 1200kg/m³The strength and the water absorption index of the plate can be directly influenced by low density.

The continuous hot press is used for producing the anti-doubling plate, after the plate is discharged from the press, the temperature of the plate is still above 100 ℃, the glue is not completely cured, and the steam bounce force still exists. After the plate leaves the hot press and is separated from the constraint of pressure, the thickness still rebounds, the density of the product becomes low, the structure is damaged, the quality of the plate is greatly influenced, and the density and the service performance of the plate are directly influenced. In addition, the plate is taken out of the hot press, and is very easy to deform in the later transportation and cooling processes, so that irreversible quality defects are brought to the plate.

Disclosure of Invention

Aiming at the problems, the invention provides an ultrahigh-density anti-bending and anti-doubling plate and a production method thereof.

In order to achieve the purpose, the invention adopts the technical scheme that: the super-high-density anti-bending anti-doubling board is a wood pulp anti-doubling board, and the density of the wood pulp anti-doubling board is 1200-1500kg/m³The static bending strength is more than or equal to 60 MPa.

The production method of the ultrahigh-density anti-bending and anti-doubling plate comprises the following steps: preparing materials, slicing, washing, cooking, hot grinding, gluing, drying, paving, prepressing, steam steaming and preheating a plate blank, continuously hot pressing, continuously cold pressing, maintaining, sanding, cutting and warehousing, wherein the pressure in the continuous hot pressing step is not less than 3.5MPa, the curing rate of glue in the plate after continuous hot pressing is controlled to be 60-80%, the temperature of the plate after hot pressing is reduced to room temperature in the continuous cold pressing step, and the plate is continuously shrunk by applying pressure in the cooling process.

Preferably, the steam jet preheating of the blank is to spray superheated steam on the upper surface and the lower surface of the blank before entering the continuous hot press to realize preheating so as to soften the wood fiber in the blank.

Preferably, the continuous hot pressing step is performed by using a double steel belt continuous flat press for hot pressing the slab.

Preferably, in the step of continuous cold pressing, the hot-pressed plate is subjected to cold pressing by using a continuous cold press, and a circulating cooling device is arranged in a pressing plate of the continuous cold press.

Preferably, the circulation cooling device is a cooling water circulation cooling device.

Preferably, the sizing step has a ratio of sizing solids to oven dry fibers of 0.6: 1.

Preferably, the hot wind pressure in the drying pipeline in the drying step is 6800Pa and the wind speed is 38 m/s.

Compared with the prior art, the invention has the advantages and positive effects that:

compared with the prior art, the ultra-high density bending-resistant and anti-double special plate has the advantages that (1) the density is high, the static bending strength is high, and the water absorption expansion rate is low; (2) the upper surface and the lower surface of the plate blank before entering the continuous hot press are subjected to steam-spraying preheating by superheated steam, and the finished product obtained by hot-pressing the plate blank after the superheated steam is subjected to steam-spraying preheating has better quality; (3) and the glue curing rate after continuous hot pressing is reasonably controlled, so that the density of the plate is further improved in the subsequent continuous cold pressing process.

Drawings

In order to more clearly illustrate the technical solution of the embodiment of the present invention, the drawings used in the description of the embodiment will be briefly introduced below, and fig. 1 is a schematic flow chart of the production process of the ultra-high density bending-resistant and anti-doubling plate provided in embodiment 1.

Detailed Description

In order that the above objects, features and advantages of the present invention can be more clearly understood, the present invention will be further described with reference to the accompanying drawings and examples.

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, however, the present invention may be practiced in other ways than those specifically described herein, and thus the present invention is not limited to the specific embodiments of the present disclosure.

Example 1

The invention is further described with reference to the attached figure 1, wherein the super-high density bending-resistant and anti-doubling board is a wood pulp anti-doubling board, and the density of the wood pulp anti-doubling board is 1200-1500kg/m³The static bending strength is more than or equal to 60 MPa.

As shown in fig. 1, the method for producing the ultra-high density anti-bending anti-doubling plate comprises the following steps: preparing materials, slicing, washing, cooking, hot grinding, gluing, drying, paving, prepressing, steam jet steaming and preheating a plate blank, continuously hot pressing, continuously cold pressing, maintaining, sanding, cutting and warehousing, wherein the pressure in the continuous hot pressing step is not less than 3.5MPa, the curing rate of glue in the plate after continuous hot pressing is controlled to be 60-80%, the temperature of the plate after hot pressing is reduced to room temperature in the continuous cold pressing step, and pressure is applied in the temperature reduction process to enable the plate to continuously shrink.

Material preparation: the wood with the growth cycle of more than 3 years is selected, the strength of wood pulp fibers is increased, the strength and the tensile force of the fibers are improved, and the physical properties of the board are guaranteed.

The hot-milling step uses a high compression ratio tear screw to directly break down the fibers.

The plate blank steam injection preheating is to spray superheated steam on the upper surface and the lower surface of the plate blank before entering the continuous hot press to preheat wood fibers in the plate blank. The hot pressing factor of the plate blank after the steam injection can be greatly shortened after the plate blank enters the press, the pressure of the press can be greatly reduced due to the fact that the raw materials are softened in advance, the moisture in the raw materials can be more balanced due to the injection of steam, and the quality of the product can be further improved.

And in the continuous hot pressing step, a double-steel-belt continuous flat press is adopted to carry out hot pressing on the plate blank. The plate blank enters the press machine under the clamping of the upper and lower steel belts, the upper and lower surfaces of the plate blank are pressurized and heated simultaneously, the upper and lower section structures of the product can be ensured to be consistent by the process mode, and the physical performance and the dimensional stability of the product can be ensured. The simultaneous pressurization and heating of the plate blank can also be used for obtaining a reasonable surface high-density layer of the product, and the static bending strength, the elastic modulus and the deformation resistance of the product are improved.

And in the continuous cold pressing step, a continuous cold press (independently developed and developed, non-market products) is used for cold pressing the hot-pressed plate, and a circulating cooling device is arranged in a pressing plate of the continuous cold press. The circulating cooling device is a cooling water circulating cooling device. The continuous cold press cools down and continues to exert pressure to the product, continues shrink after the product pressurized, and density increases, and the degree of solidification of glue is also constantly strengthening simultaneously, and the quality of product can obtain very big promotion like this.

The ratio of sizing solids to oven dry fibers in the sizing step was 0.6: 1.

The wind pressure of hot wind in the drying pipeline in the drying step is 6800Pa and the wind speed is 38 m/s.

The above description is only a preferred embodiment of the present invention, and is not intended to limit the present invention in other forms, and any person skilled in the art may apply the above-mentioned technical details to other fields by using the equivalent embodiments with equivalent changes or modifications, but any simple modification and equivalent changes made to the above embodiments according to the technical spirit of the present invention may still fall within the protection scope of the technical solution of the present invention.

Claims

1. The ultrahigh-density bending-resistant and anti-doubling board is a wood pulp anti-doubling board and is characterized in that the density of the wood pulp anti-doubling board is 1200-1500kg/m³The static bending strength is more than or equal to 60 MPa.

2. The method for producing an ultra-high density anti-buckling anti-doubling plate as claimed in claim 1, comprising the steps of: preparing materials, slicing, washing, cooking, hot grinding, gluing, drying, paving, prepressing, steam steaming and preheating a plate blank, continuously hot pressing, continuously cold pressing, maintaining, sanding, cutting and warehousing, wherein the pressure in the continuous hot pressing step is not less than 3.5MPa, the curing rate of glue in the plate after continuous hot pressing is controlled to be 60-80%, the temperature of the plate after hot pressing is reduced to room temperature in the continuous cold pressing step, and the plate is continuously shrunk by applying pressure in the cooling process.

3. The method for producing ultra-high density anti-bending and anti-doubling board as claimed in claim 2, wherein the pre-heating of the steam injection of the board blank is to spray the superheated steam on the upper and lower surfaces of the board blank before entering the continuous hot press to soften the wood fibers in the board blank.

4. The ultra-high density anti-buckling and anti-doubling plate production method as claimed in claim 2, wherein the plate blank is hot-pressed by using a double steel belt continuous flat press in the continuous hot-pressing step.

5. The method for producing the ultra-high density bending-resistant and anti-doubling plate as claimed in claim 2, wherein the step of continuously cold-pressing utilizes a continuous cold press to cold-press the hot-pressed plate, and a circulating cooling device is arranged in a pressing plate of the continuous cold press.

6. The method for producing ultra-high density anti-bending and anti-doubling board as claimed in claim 5, wherein the circulating cooling device is a cooling water circulating cooling device.

7. The method for producing ultra-high density bending and bending resistant doubling sheet as claimed in claim 2, wherein the ratio of the amount of the sizing solids to the oven dry fibers in the sizing step is 0.6: 1.

8. The method for producing ultra-high density anti-bending and anti-bending plywood as claimed in claim 2, wherein the hot air pressure in the drying duct in the drying step is 6800Pa and the air speed is 38 m/s.