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Plywood is a typical artificial board. It is called plywood abroad, also called multi-layer board. It has a typical odd-numbered layered structure. Each layer is superimposed perpendicular to each other.
This unique processing method creates structures that balance strength, stability and economy. Plywood does not constantly shrink and expand, deforming like solid wood. Plywood is generally from 3 to 17 layers. Generally speaking, the more layers of the same material, the better the plywood.
The quality of plywood depends on the material. Some are cork, such as pine, poplar, etc. The price of hardwood is higher than that of cork. There are also positive and negative differences between plywood, and the front is generally measured according to flatness and smoothness. There is also a side view of whether the layers are symmetrical, flat, and whether there are holes.
Plywood is a board that woodworking enthusiasts like very much, especially high-grade imported boards, which are called marine boards in the industry. In fact, in recent years, the production process of domestic plywood has been greatly improved, and the processed plywood is no worse than imported plywood, whether it is environmental protection or quality. aspect. The formaldehyde content of the glue used has reached and exceeded the European standard
How to make plywood?
Plywood making Plywood processing technology:
Plywood processing technology:
In the producing process, log cutting, peeling, dry, handling, hot press, edge trimming, sanding affect the wastage. The wastage is remains of processing (materiality) and shrinking (immateriality). Wood wastage is related to the material, specification of log, equipment capability, technology and production specification.
1) Log debarking:
Usually import log length is more than 6 meters. Cutting according to the technology required length and quality. The cutting length should be product length add remains. For example, product is 1220mm*2440mm, cutting length usually be 2600mm or 1300mm. log length, camber and demerit affect plywood output directly. Remains are small wood pieces, truncations, sawdust, tec. Log cutting wastage ratio is 3%-10%.
2) Veneer peeling:
Peeling is the most popular plywood producing process. Back veneer thickness is about 0.6mm, core veneer and centre veneer thickness is about 1.8mm.
Veneer is moist. it should be dried according to the technology requirement. After drying, it will shrink. Dimension will become smaller. Veneer length, width, thickness will shrink. Shrink wastage is related to wood material, moisture containing, veneer thickness. Shrink wastage is 4%-10%.
1.Steel Tube drying (The most economic type dryer,but capacity is less)
2.Solid hot platen press drier ( If your board is not flat you can choose hot platen solid press dryer.)
3.Core Veneer Continuous roller dryer ( If your capacity is bigger than 50cbm per day, you can choose roller dryer. )
4) Veneer handling:
Handling include cutting, putting veneer together and mending. Cut zonal veneer into specification veneer or proper size which can be put together. Narrow zonal veneer can be put together into one veneer. Veneer with demerit can be mended to be qualified. Wastage in this part related to log material, peeled veneer quality, dried quality, and worker operation skill. Wastage ratio is 4%-16%. Import veneer processing plywood wastage ratio is 2%-11%.
Veneer assemble line or hand assemble
5) Cold Press:
The cold press the basic machine for plywood plant. This machine is also called pre-press. The veneer after glued and assemble, first it will be formed in to the blank panle by the cold press. Then it will be transferred by forklift to the hot press.
6) Hot press:
Veneer be glued and stacked, then glue together under set temperature and pressure by hot press. As veneer temperature and moisture containing changes, veneer will shrink. Shrink wastage is related to temperature, pressure, hot press time, wood material, moisture containing, wastage ratio is 3%-8%
7) Edge trimming:
Trimming the edge of the plywood flank from hot press to qualified plywood board. Remains related to process remains and product dimension. Production is bigger, wastage is smaller. Wastage ratio is 6%-9%
Sanding plywood surface to make it good. Wastage is powder. Veneer quality is good, sanding is less. Wastage ratio is 2%-6%
Plywood is packing in palletize or in bulk
(10) Laminating with veneer, melamine paper, membrane paper etc.
Finished plywood products