The Process Flow of Plywood Furniture

(1). Processing technology loss of plywood furniture

In the whole production process of plywood furniture, log sawing, veneer rotary cutting, veneer drying, veneer finishing, hot pressing, edge cutting and cutting have an impact on wood loss, which is divided into tangible loss (with processing residues) and intangible loss (drying shrinkage and compression). Wood loss is related to log species, log specifications, equipment conditions, process technology and finished board specifications.

(2). Sawing of plywood furniture logs

The length of the log is generally more than 6m, which shall be sawn according to the length and quality required by the process. The intercepted wood section shall be the length of the finished size of high quality plywood for furniture plus machining allowance. For example, for finished plywood with a width of 1220mm*2440mm, the length of wood section is usually 2600mm or 1300mm. The length of the log, the curvature and defects of the log directly affect the yield of plywood. The waste produced includes small wood segments, truncated heads and sawdust. The sawn loss rate of the log is generally 3 to 10%.

(3). Veneer rotary cutting of plywood furniture

The most widely used veneer in the production of plywood furniture is the veneer produced by the peeling method. The thickness of the back boards is generally about 0.6mm, and the thickness of the core board and the long middle board is generally about 1.8mm. The loss of this process is the largest. One is due to the out of roundness of the wood section, and a considerable part of the broken veneer cannot be used; the other is the end loss caused by the clamping of the chuck of the rotary cutting machine to the ends of the wood section; the third is the loss of the wood core. The waste generated by the veneer peeling is broken veneer and wood core. It can be seen that the loss of veneer peeling is related to the material, diameter and equipment performance of the wood section. The loss rate of this part is 15% to 25%.

(4). Plywood furniture veneer drying

The moisture content of the veneer after rotary cutting is very high, so the veneer must be dried to meet the requirements of the gluing process. After drying, the size of wood becomes smaller, which is called drying shrinkage. Due to the decrease of moisture content, the length, width and thickness of veneer will shrink. Drying shrinkage loss is related to veneer species, veneer moisture content and veneer thickness. The shrinkage loss rate is generally 4% to 10%.

(5). Veneer finishing of plywood furniture

Veneer finishing includes cutting, splicing and repair. The dried strip veneer and zero veneer are cut into specification veneer and splicing veneer. The narrow veneer is spliced into the whole veneer. The defective whole veneer can meet the quality requirements of the process through repair. The amount of waste veneer produced in this process is related to factors such as log material, rotary veneer quality, dry veneer quality and operators' familiarity with veneer standards. The loss rate is generally 4% to 16%. The loss rate of the process of directly importing veneer into plywood is generally 2% to 11%.

(6). Hot pressing, trimming and sanding of plywood furniture

The glued slab is firmly glued through a certain temperature and pressure. During hot pressing, with the change of slab temperature and moisture content, the wood is gradually compressed and the slab thickness is gradually reduced. This loss is compression loss, which is related to factors such as hot pressing temperature, unit pressure, hot pressing time, the species of tree and moisture content of plywood furniture. The loss rate is generally 3% to 8%.

Cut the hot pressing rough board into standard board. The amount of waste material at the edges and corners is related to the processing allowance and width of plywood. The larger the width of plywood, the smaller the edge cutting loss rate, which is generally 6% to 9%.

Sanding the surface of plywood furniture to make the board surface smooth and beautiful. The waste produced in this process is sanding powder. When the veneer quality is good, the sanding amount is small, and the sanding loss rate is generally 2% to 6%.