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| Plywood | Wood-Based Panel Doors | Hard Board | By-Product and Deplete Products |
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Bangna hardboard is one of Thai Plywood's best selling products. It is a wet-process
| hardboard, made up entirely of selected hardwoods species mostly plantation grown Eucalyptus. Bangna hardboards are made without additional binders. Lignin in wood is retained during the refining operation, lignin can serve as the binders.Under high heat and pressure, lignin will flow and act as a thermosetting adhesive. Because of no adhesive addition, therefore, Bangna hardboards are free from formaldehyde. |
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| Manufacturing Process |
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| First, logs or billets are reduced to chips. Chips are conveyed to chip bin, and preheated before defining. The preheated chips are fed to the refiner or defibrator to refine chips into fibers and fiber bundles which are called pulp. The pulp is blown to the cyclone separator, and then transferred to the stock chest in order to regulate the consistency of pulp in water. Water is used as the distribution medium for forming the fibers into a wet lap on the forming machine whereby the water is sucked and squeezed. The wet lap is than cut by high pressure water jets into pieces of approximately 4' x 8'. The wet laps are fed into a hydraulic hot-press where they are subjected to a pressure of 20-55 kg/cm2 at a temperature of 200๐C for varying times of press cycle depending on the thickness of the board. The water left in the wet lap is pressed through the wire screen, and the resulting board becomes dense and intact with one smooth surface. The pressed fiberboard is then exposed to dry heat for four hours to improve dimensional stability and mechanical properties, and to reduce water absorption. Humidification of the boards moisture content into equilibrium with the air. Finally the boards are trimmed to exact size, graded, stamped the grade and company's board, and sent to the warehouse. |
| The entire process is fully automatic which ensures the consistent quality, density and appearance of the boards. |
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| Features and Sizes |
| Bandna hardboard is produced in standard class with smooth one face (S-1-S). There are three grades of board, A, B and C depending on the consistency of the colour and certain defects such as blistering, peeling, cracking, stain and black spot on the smooth surface. |
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| The colour of the board is reddish brown to dark brown which is ready to use without paint or finishing. Unless for special application Bangna hardboard can easily be coated with any finishes and paints or overlaid with variety of other materials. |
| Bangna hardboard is produced in standard size of 1220 mm. by 2440 mm. The thickness is available in 2.5, 3.0, 3.2, 4.0, 5.0, and 6.0 mm. |
| In addition to the smooth suface board, we also produce the embossed board in various figures which is called Bangna Fancy Hardboard, and the perforated boards. |
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| Properties |
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Density: 8,000-1,200 kg/m3 |
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Moisture content: 3-12 % |
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| Modulus of Rupture (MOR): |
min. 38.0 MPa (for 2.5 and 3.0 mm. panel thickness) |
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min. 35.0 MPa (for greater than 3.0 mm. panel thickness) |
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Water Absorption: Av. 52% |
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Thickness Swelling: Av. 27% |
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| Application |
| The uses for hardboard can be grouped as construction, furniture and furnishings, carbinet and store, appliances, and automotive and rolling stock. |
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