A series type continuous automatic plywood production method, at least comprising the following steps:
- (1) core layer initialization comprising:
- S10:
- surface sanding a thin board with a thickness of 2-6 mm as an initial core layer by using an abrasive belt having a 60-120 mesh surface to obtain a first sanded core layer;
- S20:
- gluing the first sanded core layer by coating 100-300 g/m2 of a first adhesive having a curing temperature of 60-80° C. on each side of the first sanded core layer to obtain a first coated core layer;
- S30:
- automatically laying-up the first coated core layer with first sheeted veneer timbers using a robot to obtain a first laid-up core layer, wherein the first sheeted veneer timbers on an upper surface and a lower surface of the first coated core layer have the same grain direction;
- S40:
- subjecting the first laid-up core layer to a first constant-thickness hot pressing at a temperature of 80-100° C., to achieve 80-90% curing in the first adhesive, so as to obtain a first pre-cured semi-finished product;
- S50:
- subjecting the first pre-cured semi-finished product to a first board overturning and a first cooling, to form a first preformed semi-finished product, wherein the first preformed semi-finished product has a surface temperature of 50-70° C.;
- and
- S60:
- defect scanning and repairing by using an automatic scanning device to distinguish defects in the first preformed semi-finished product and repairing detected defects to obtain an initialized core layer;
- (2) thickening circulation comprising:
- S70:
- surface sanding the initialized core layer by using the abrasive belt having the 60-120 mesh surface to obtain a second sanded core layer;
- gluing the second sanded core layer by coating 200-500 g/m2 of a second adhesive having a curing temperature of 80-90° C. on each side of the second sanded core layer to obtain a second coated core layer;
- automatically laying-up the second coated core layer with second sheeted veneer timbers using the robot to obtain a second laid-up core layer, wherein the second sheeted veneer timbers on an upper surface and a lower surface of the second coated core layer have the same grain direction, which is perpendicular to the grain direction of the upper surface and the lower surface of the second coated core layer;
- subjecting the second laid-up core layer to a second constant-thickness hot pressing at a temperature of 100-120° C., to achieve 60-80% curing in the second adhesive, so as to obtain a second pre-cured semi-finished product;
- subjecting the second pre-cured semi-finished product to a second board overturning and a second cooling, to form a second preformed semi-finished product, wherein the second preformed semi-finished product has a surface temperature of 50-70° C.;
- and
- defect scanning and repairing by using the automatic scanning device to detect defects in the second preformed semi-finished product and repairing detected defects to obtain one of a plurality of semi-finished products;
- directing a group of the plurality of semi-finished products not reaching a thickness requirement to re-enter the thickening circulation and another group of the plurality of semi-finished products meeting the thickness requirement to enter a product setting process unit after a thickness inspection and shunting procedure;
- and
- (3) product setting comprising:
- S80:
- surface sanding one of the another group of the semi-finished products meeting the thickness requirement by using the abrasive belt having the 60-120 mesh surface to obtain a third sanded core layer;
- gluing the third sanded core layer by coating 200-500 g/m2 of a third adhesive having a curing temperature of 90-100° C. on each side of the third sanded core layer to obtain a third coated core layer;
- automatically laying-up the third coated core layer with third sheeted veneer timbers using the robot to obtain a third laid-up core layer, wherein the third sheeted veneer timbers on an upper surface and a lower surface of the third coated core layer have the same grain direction, which is perpendicular to the grain direction of the upper surface and the upper surface of the third coated layer;
- subjecting the third laid-up core layer to a third constant-thickness hot pressing at a temperature of 120-180° C., to achieve 60-80% curing in the third adhesive, so as to obtain a third pre-cured semi-finished product;
- and
- subjecting the third pre-cured semi-finished product to a third board overturning and a third cooling, to form a finished product, wherein the finished product has a surface temperature of 50-70° C.