Why do some parquets produce bending deformation?

The multi-layer solid wood composite floor is a composite floor made of multi-layer plywood and coated with solid wood skin. The type of raw materials and processing techniques of the substrate can cause bending deformation of the flooring product. The deformation factors can be summarized as follows:

1, the impact of multi-layer solid wood composite flooring raw materials

The raw material (single board) of the substrate is made of the same tree species, and the dry shrinkage coefficient of the wood is similar, and the substrate is not easily deformed. Sometimes the use of miscellaneous wood, especially the density of wood, the mixing of the wood with different shrinkage coefficients, forming asymmetric stresses on both sides of the central layer of the substrate, causing the floor substrate to bend or twist. Therefore, if we use wood as the raw material of the multi-layer solid wood flooring substrate, we should try to use the tree species with similar specific gravity and material properties. The same tree species should be used as much as possible in the symmetrical layers on both sides of the center layer of the substrate. If conditions permit, the manufacturer can sort the purchased materials by tree species and material properties.

2. Influence of moisture content of multi-layer solid wood composite floor veneer

In the case where the water content distribution of the veneer is large, for example, in the same substrate slab, some veneers have a water content of 7%, and some veneers have a water content of 14%. After being coated and hot pressed, The water content distribution of each part of the finished substrate board is not uniform. Although the substrate sheet is flat when it comes out from the press, when the moisture content is rebalanced, bending and distortion will occur. If the moisture content of individual areas in the slab is too high, delamination will occur. Therefore, the moisture content of the veneer should be controlled as much as possible within the scope of the process. The veneer should be evenly coated, and the aging time can be appropriately extended to balance the moisture content of each layer and each point of the slab before hot pressing.

3, the effect of the internal stack (overlap) separation (separation) of the multi-layer solid wood composite substrate board

The overlap of the inside of the substrate will cause stress on the sheet. The effect of this stress on the whole substrate is not very obvious. When the substrate is sawn into a floor strip, the stress points caused by the stacking will lead to multiple layers. The parquet strips are deformed. If a serious laminate occurs within the three layers of the surface, the resulting lacquered multi-layer parquet is clearly visible in the laminate (0.6 mm thick) during use. Therefore, the middle plate must be spliced ​​to make the middle plate complete, reducing and avoiding the overlap of the middle plate.

4, the impact of the elastic surface of the multi-layer solid wood composite floor veneer

During the cutting process, the elastic surface will appear on the veneer. There are many cracks on the side of the tool. We call it the loose surface and the other side is called the tight surface. For the same veneer, the tight side is the outer circle of the wood, and the loose side is the side of the center of the wood. The stress generated by the expansion and shrinkage of the tight surface is greater than that of the loose surface. The compact should be kept facing outward and symmetrical on both sides of the central layer of the substrate.

5, the impact of sapwood and heartwood

There are differences in the shrinkage and expansion of wood sapwood and heartwood. When assembling the blank, the sapwood and the heartwood should be mixed as much as possible. It is prevented that the side of the sapwood is a heart material on both sides of the center layer of the substrate.

6. Influence of external environment on finished products of multi-layer solid wood composite flooring

Because the multi-layer solid wood composite floor coating film is thicker, the moisture is not easy to enter and exit from the surface, the paint on the back of the multi-layer solid wood composite floor is less, and no continuous film is formed, and the moisture is easy to enter and exit from the back of the multi-layer solid wood composite floor. When the multi-layer solid wood composite floor is packed, it is flat. If the packaging box is damaged during transportation, the humid air breaks in, and the back of the multi-layer solid wood composite floor absorbs moisture. After the box is opened, the multi-layer solid wood composite floor is bent toward the board surface.

In addition, many users do not install the multi-layer parquet directly after unpacking, and over-select the color difference. If the equilibrium moisture content of the environment is higher than the moisture content of the multi-layer parquet, the back of the multi-layer parquet will be in the direction of the board. Bending, if the equilibrium moisture content of the environment is lower than the moisture content of the multi-layer parquet, the back of the multi-layer parquet loses moisture and bends downward. This change is not a quality issue.

High Speed Door Accessories

About high speed Door Accessories:

1.Driving system: High Speed Door Servo System motor and control, motor SNMA / SEJ +reducer+flang+encoder+control box

2.Other accessories: Middle aluminium bar, bottom aluminium bar, aluminium vertical track, stainless steel vertical track, brushes,round nylon strip, PVC roll, rolling steel tube complete, drum be;;s for rolling tube, side end covers, stainless steel cover, steel tubes, air bag sensor system, safety light beam, Microwave sensor 24 Gigahertz,PVC welding machine, smoke and fire sensors, PVC transparent window, magnetic loop, photocell, remote control, manual push button, sound warning alarm Led lamp traffic light

For some main accessories, here is detain introduction:

1).24G radar sensor:

Brand: Hofic

Technology: Microwave processor

Maintain time: 0.5s

Protection: IP54

Transmitting frequency: 24.125GHz

Maximum installation height: <5meter

Transmitting power density: <5mw/cm2

Power consumption: <1W(VA)

Installation angle: 0-90°(lengthways) -30-30°(crosswise)

Supply voltage: AC&DC 12V-30V

2).Photocell:

Approval CE & ISO9001

Power supply AC/DC 12-30V

Static current 25A

Action current 40mA

Mounting distance Max 10m

NO or NC contact Done by NO./NC. contact selection

Working environment temperature -42℃ to +45℃

Working environment humidity 10 to 90%RH

Appearance dimensions( controller) 123*50*32mm(L*W*H)

Appearance dimensions(Magic eye head) 19*13mm(L*D)

3). Remote control

Operating Voltage: AC220V/50HZ+-20%

Transmit power:≤100mW;Super regenerative module, strong anti-interference

Operating temperature:-30℃-+70℃

Working frequency: 433MHZ;transmitter 1527, millions of encoding chip

Accept sensitivity:≤110dB

Manipulation method: electric remote control

Configure the quantity: Wireless number; factory configuration transmitter two. Can be equipped with PT2272 digital decoder chip

Configure the function: Up, down, stop, anti-lock full-featured reproduction

4). Magnetic loop

Voltage: 12V AC/DC +-10% 24V 115V AC+-10% 230V

Power: <2VA

Continued electrical output: 7A / 250V AC

Frequency range: 20 to 200K Hz

Response time: infinity (factory setting) or adjust maintain time

Sensitivity: 0.01% to 0.1% divided into 3 levels

Protection level: IP30

Electromagnetic compatibility (EMC) Complies with EM50081-1 and EN50082-2

Detection loop inductance: the limit of 40uH to 100uH ideal value 80uH to 300uH

Operating temperature: -25 ℃ to 70 ℃

Storage temperature: -40 ℃ to 85 ℃

Relative humidity: <90% non-condensing

Temperature compensation: automatic compensation up to 50 ℃ / h

Connection type: 11 pin DIN rail socket

Dimensions: 41 * 78 * 85 mm (width * height * length)

Weight: 250 grams

5). manual push button

This exit switch button is made of ABS and has built-in indicator light make it looks more elegant and fashionbale. It can be widely used in public entrance gates, public door, home, office, hotel, etc.

Door Exit Button Push To Exit Switch Door Opener For Access Control Security

Main Feature

Fashionable appearance

Made of ABS Plastic

Easy to install and operate

Used for access control

Specification

Mechanical Life: 500,000 test

Material: Plastic

6). Limit switch encoder

Voltage: DC5V-24V

Output voltage: high voltage≥85%Vcc, low voltage≤0.5V

Maximum mechanical speed:6000rpm

Anti-vibration: 50m/s,10-200HZ,XYZeach way 2 times.

Current consumption:≤30mA

Response frequency: 0-100KHZ

Protection: waterproof,oil proof,dust prevention, IP54

The output code system: binary code

Operating life: MTBF≥30000(+25℃,2000rpm)

Rotational inertia:4.0x10-8kgm²

Maximum load:radial direction20N

Axial direction:10N

Weight: about 0.4kg

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Shenzhen Hongfa Automatic Door Co., Ltd. , https://www.pvchighspeeddoor.com