SU1761468A1 - Method of manufacturing composite veneer - Google Patents

Abstract

Usage: wood industry, manufacturing of laminated wood laminates. SUMMARY OF THE INVENTION: A prepared mass of a mixture of wood particles and a binder is pressed in a one-floor press. The consumption of absolutely dry resin is 12% by weight of absolutely dry chips, the hardener consumption is 1% by weight of resin. Pressing pressure adhesive mass of 1.4-1.8 MPa to a density of 400-600 kg / m3 and a thickness exceeding by 20-30% its final thickness in composite plywood. The pressing time of the composite is 20-30% less than required for complete completion binder polycondensation process A sheet of composite chipboard is applied to a dry face layer of veneer with a binder deposited on its surface at a rate of 120 g / m. Then a dry layer of veneer is laid on it. The package is compacted to a constant value specified thickness of the finished product. 1 tab. (Ls

Description

The invention relates to the woodworking industry and can be used in plywood, furniture and other industries in the manufacture of laminated wood laminates.

The purpose of the invention is to reduce the consumption of raw materials and improve the quality of plywood by reducing its thickness variation.

Under laboratory conditions, the invention is carried out as follows. The prepared pressmass from a mixture of wood particles and a binder is pressed in a heated press. Absolutely dry resin consumption is 12% by weight. Absolutely dry.

shavings, hardener consumption - 1% by weight of resin

Thus, a chipboard composite is obtained with a thickness of from 3 to 10 mm with a density of not more than 600 kg / m. The resulting material is fed to the assembly site, which form a package of composite plywood. The package of a three-layer structure is assembled in the following sequence. A sheet of a wood-resin composite with a binder deposited on its surface at the rate of 120 g / m is laid on a dry face layer of a veneer, then a dry layer of veneer is laid on it and the direction of the fibers of the veneer layers is parallel

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A package of five-layer construction is assembled in the following sequence. A layer of veneer is deposited on a dry face layer of veneer with a binder applied on its surface on both sides. Then a sheet of chipboard composite is laid, a layer of veneer with a bonding agent is applied on it, and finally a dry layer of veneer. The direction of the fibers of the outer layers and the layers with the applied binder should be mutually perpendicular. The binder is not applied to the central layer, which is a chipboard composite sheet. The collected bags are loaded into a press with heated plates and pressed one sheet at a time with spacers. At the end of the pressing process, the plywood is unloaded from the press and, after cooling to a temperature of no more than 30 ° C, is cut to the format.

For comparison, composite plywood is pressed in a manner known per se. A binder is applied to the veneer sheet, a layer of tarred chips is poured onto it, and the sheet is covered with a binder on the underside of the veneer sheet. Binder consumption is similar to that described above.

In all cases, urea-formaldehyde resin with a hardener ammonium chloride is used as a binder, and birch shavings with a maximum size of not more than 4 mm and birch peeled veneer 1.5 mm thick are used as wood binder.

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The table shows the comparative characteristics of the proposed and known methods.

The use of the invention will make it possible to reduce the consumption of raw materials, characterized by a change in the density of plywood, to ensure the multivariance of plywood structures that best suit the specific purpose, as well as to improve the quality of products by reducing the heterogeneity of plywood.

Claims (1)

Claims method of manufacturing composite plywood 5, comprising preparing a sponge-glue mass, assembling a bag with outer layers of veneer, applying a binder to the components of the bag, and then pressing it hot, in order to reduce consumption raw materials and improving the quality of plywood by reducing its thickness, the inner layer of the package is formed from a composite prepared from chip-adhesive mass at a pressure of 1.4-1.8 MPa to a density of 400-600 kg / m3 and a thickness exceeding by 20 -30% of it to There is a finite thickness in composite plywood, while the duration of pressing the composite is 20-30% shorter than the binder required to complete the polycondensation process, and the hot pressing of the bag is carried out to a constant amount of deformation determined by a given thickness of the finished product. 0 balancing posite temperature, С pressing time, min / mm degree of binder cure,% compaction pressure, MPa thickness to obtain comp. plywood thickness, mm 6.0 8.0 10.0 12.0 Veneer-glue-osmolenna shavings-glue-veneer Without spacers (with variable deformation) Table continuation Veneer glue-composite veneer Veneer glue veneer glue composite glue-veneer glue veneer With spacers (with constant deformation)