Sliced wood veneer
Thin wood (commonly known as veneer; hereinafter referred to as veneer) and its veneer decoration industry started in the 1950s, after half a century of development, has a considerable scale. Especially in the past two decades, with the leap-forward growth of furniture manufacturing and decoration industry in China, its development has made great strides and a large number of experts have emerged.
Over the past decade, veneer veneer technology has been widely used in furniture manufacturing and decoration industry in China.
1. Classification by thickness
Thicker than 0.5 gill is called thick thin wood; on the contrary, it is thin wood.
2. Classification by manufacturing method
It can be divided into planing thin wood, rotary thin wood, sawing thin wood, semi-circular rotary thin wood. Usually, planer cutting method is used to make more.
3. Classification by morphology
It can be divided into natural veneer, dyed veneer, composite veneer (technical veneer), spliced veneer, rolled veneer (non-woven vens).
4. Source classification
Domestic thin wood; imported thin wood.
Quality Project of Thin Wood
1. Thickness and uniformity, length and width, error and moisture content
2. Early wood and late wood
Within each ring, the pith core is formed at the beginning of each growing season. It is called early wood (spring wood) because of its light color, loose tissue and soft material. Late wood (autumn wood, summer wood) is called late wood because of its dark color, dense tissue and hard material.
3. Sapwood and Heartwood
Some tree species have light wood color near the bark. When the tree falls down, the water in this part is more, called sapwood. The part with darker color and less moisture around the pith core is called heartwood.
4. Patterns, chromatic aberration, smoothness, mineral lines
Planing thin wood manufacturing process
Usually, the natural veneer is processed by planing. The process flow is as follows:
Log Truncation Cutting Softening (Steaming or Boiling) Planing Drying (or Not Drying) Shearing Inspection Packaging Storage
Here are only three important links:
After entering the factory, the logs should be cut into sections according to the required length first, and then cut into wooden blocks. The sawing scheme must be selected according to the diameter of logs, wood texture and the fixed method of the logs on the planer, so that the width of the planned thin wood is not less than the relevant requirements.
Reasonable plan not only has a high yield, but also produces more diameter-cut thin wood and fewer chord-cut thin wood, resulting in high decorative value of the products. Different sawing schemes should be adopted for logs of different diameters. The thick solid line in the figure is a sawing line, and the arrow direction is the cutting direction of the planer.
In actual production, sawing scheme B is usually used for logs with diameter less than 400 mm, while sawing scheme D and E are mostly used for logs with diameter between 400 and 800 mm. When using these sawing and cutting schemes to produce thin wood, the board yield is high, the quality of thin wood is good, and the efficiency of planer is high.
The plasticity of wood increases after cooking (i.e. hydrothermal treatment). The most effective way to improve wood plasticity is to adjust the temperature and moisture content simultaneously, that is, to increase the temperature of wood and the moisture content of wood at the same time. This is the reason why the wood square is usually boiled with saturated steam or hot water in practical production.
Firstly, when putting the wood into the cooking pool, it should be carried out according to the tree species and the wood specifications respectively; the water temperature should be kept at room temperature, and the temperature should be raised slowly, so as to avoid cracking of the wood due to thermal stress. When the temperature rises above 40 C, the heating rate should be slowed down; excessive cooking will also reduce the quality of thin wood; cooking pools should often remove resin, bark, sediment, and often change water to reduce wood pollution; after cooking, the wood should be placed in the storage tank in time before planing and cutting machine, and kept in the temperature range of 40-50 C (with tree species and sediment). The thickness of veneer depends. The following table lists the cooking benchmarks for several types of wood for reference only.
The moisture content after drying is generally 8%~12%. Thin wood drying equipment includes continuous drum dryer, belt dryer and intermittent drying room. Drying chamber is an old-fashioned drying equipment, which is not economical, but the drying quality is better. The most widely used is the drum dryer. Comparatively thin wood, especially those less than 0.4mm in thickness, must be dried by belt dryer.如无特殊说明，文章均为本站原创，转载请注明出处。If there are no special instructions, the articles are original, if you want to use or reproduce, please indicate the original source www.plywoodinspection.com,If you find that our articles infringe on your copyrights and interests, please email us at email@example.com in time and we will delete it at the first time.