Panels & Furniture Asia January/February 2021

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WOOD CLINIC Hello, Mr Shen! We are a supplier of building materials in Indonesia and we often find rot and pests on the timber in our warehouses. In your column published in Panels and Furniture Asia, I read about the high-temperature kiln drying of wood and the treatment of carbonised wood. We plan to build a kiln of 20 cubic meters to test the high-temperature drying of wood and the treatment of carbonised wood, and we hope to solve the problems of pests and rotting wood. In the future, we plan to increase preservation equipment for wood treatment to meet the needs of customers. We hope that you may provide information about wood preservation for our reference. Thank you! Sincerely, Chen Zhiping, Indonesia 20 June 2020 Wood preservation treatment using the Bethell full-cell process Mr Chen, thank you for your letter. First of all, it is necessary to consider the causes of wood damage, which are mainly divided into two categories: pests (eg, longicorn beetles, beetles and termites) and decaying fungi (eg, brown rot fungi, white rot fungi and soft rot fungi). Secondly, the role of preservatives is also related to its durability, penetration effect and penetration uniformity. Thirdly, the preservation treatment methods include spraying; soaking; cold soaking; hot soaking; hot and cold soaking; vacuum soaking; and the Bethell full-cell process, among others. Finally, it is necessary to choose a wood preservative treatment method that is harmless and in line with the needs of the users. BETHELL FULL-CELL PROCESS The Bethell full-cell process is currently the most common wood preservation treatment thanks to its yield, quality and suitability for a wide range of wood. It involves a cylindrical pressure tank with a diameter of about 1.5 meters and a length of about 15.5 meters, and a capacity of about 9 to 10 cubic meters of wood. Things to note during preparation • The moisture content of air-dried wood is 20% to 25%. • Ideally, the wood placed in the pressure tank for treatment should be of the same species and specifications. • The presence of bark may affect the penetration of preservatives into the wood tissues. Bark that fall off may also cause a jam in the pressure tank pipes or pumps. • The width and height of the material pile should be smaller than the inlet (circumference) of the pressure tank to avoid damaging the surface coating. • For wood surfaces that have a low penetration rate, it is necessary to carve cracks to facilitate better penetration of preservatives into the wood tissues. • High-density hardwoods, or extracts with antiseptic effect in cells, do not need preservative treatment. An example is ironwood (ulin) in Malaysia and Indonesia. • Moths can often be seen in wet sapwood, but after air drying, the wood will maintain its integrity even for a hundred years. Procedure (see Figure 1) 1. Vacuumise the wood in the pressure tank until the pressure reaches 0.85bar. Maintain the pressure for about 30 minutes (too much vacuum pressure or vacuum time may cause the wood to become deformed). 2. Remove moisture on the wood surface and air in the cell cavity to facilitate the better penetration of preservatives into the wood tissue. 3. After 30 minutes, open the valve 58 Panels & Furniture Asia | January / February 2021
WOOD CLINIC and suck the preservatives from the preservative storage pool. After filling the pressure tank, pump the vacuum pump to close the valve. 4. Open the pressure pump and increase the pressure to 14bar, maintaining it for one hour or longer as appropriate. 5. After the pressure-holding phase ends, open the valve of the pressure tank to discharge the remaining preservatives to the storage pool. 6. Start the vacuum pump to drain the wet preservatives from the wood surface and immediately complete the full-cell process within 15 minutes. 7. Confirm that all remaining preservatives in the pressure tank have been drained into the storage pool before opening the door of the pressure tank to unload the wood for air drying. Selection of preservatives There are many kinds of preservatives in the market and they should be selected according to their environmental hazard level. One possibility is Copper Chromium Arsenic (CCA). Chromium is a fixing agent in CCA preservatives and can prolong the effectiveness of preservatives in wood tissues. Copper and arsenic play a role in preventing decaying fungi and moths. Basic safety matters 1. Preservative treatment workshop a. Workshop ventilation equipment: the workshop should have good ventilation equipment, especially at the entrance of the preservative pressure tank or the mixer for diluting preservatives. The equipment can pump the gas volatilised by preservatives away from the workshop. b. Wastewater treatment: there should be a facility for treating the wastewater recovery tank. c. Safety dike: a safety dike should be set around the pressure tank to prevent the preservative from leaking all over the ground. d. Emergency shower room: set up an emergency shower room at an appropriate location. e. Eye washing equipment: set up eye-washing facilities in appropriate working areas. If CCA gets into contact with the eyes, wash immediately for about 15 minutes to avoid damaging the cornea. f. Hand washing equipment: there should be a sink near the working area. g. Back-up water tank: a back-up 图一、全细胞防腐处理的程序如示意图一。a. 啟动抽真空泵 water , a1 tank 直空 is necessary 保压时 in 間 case ,b. 吸入防腐剖 , c. 啟动加压力泵压力达 14bar, d. 保压時間 , e. 减压 , f.CCA 防腐 of 剂 a temporary 回收 , g. shortage 抽真空 of , tap g1 真空时間 , water. h. 觧除真空压力。 15 d 12 Pressure (bar) 9 6 3 0 -1 a a 1 c b Time (hour) g e f g 1 h Figure 1. Schematic diagram of the Bethell full-cell process Legend a. Start the vacuum pump a 1 . Vacuum duration b. Add preservatives c. Open the pressure pump and increase the pressure to 14bar d. Pressurisation duration e. Decompression f. CCA preservative recovery g. Vacuumise g 1 . Vacuum duration h. Release the vacuum pressure 1 Panels & Furniture Asia | January / February 2021 59
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JANUARY/FEBRUARY 2021
Page 6 and 7:
CONTENTS 42 26 33 51 4 Panels & Fur
Page 8 and 9:
FROM THE EDITOR New year, renewed h
Page 10 and 11: NEWS PANELS & FURNITURE ASIA AND PA
Page 12 and 13: NEWS LIGNA.21 POSTPONED TO SEPTEMBE
Page 14 and 15: NEWS VIETNAM: PRIVATE SECTOR COMMIT
Page 16 and 17: NEWS BRAZIL: FOREST SECTOR INVESTME
Page 18 and 19: NEWS IPCO APPOINTS ROBERT HERMANS A
Page 20 and 21: MARKET REPORT 2020 rolls into 2021:
Page 22 and 23: MARKET REPORT Today to 2026: An ove
Page 24 and 25: MARKET REPORT Pandemic gins up Russ
Page 26 and 27: MARKET REPORT specifications: “Mu
Page 28 and 29: ENVIRONMENT REPORT Inside the fores
Page 30 and 31: ENVIRONMENT REPORT appointed to con
Page 32 and 33: PRODUCT HIGHLIGHT “All-in” solu
Page 34 and 35: PRODUCT HIGHLIGHT First-of-its-kind
Page 36 and 37: FURNITURE MANUFACTURING Innovative
Page 38 and 39: FURNITURE MANUFACTURING electronic
Page 40 and 41: FURNITURE MANUFACTURING SalvaPush_2
Page 42 and 43: PANEL MANUFACTURING Diamond-tipped
Page 44 and 45: IN PERSON Roger&Sons: Giving local
Page 46: IN PERSON 1 2 3 Legend 1 These benc
Page 49 and 50: MATERIALS 3 production of Machine S
Page 51 and 52: MATERIALS three years, the shipment
Page 53 and 54: STRUCTURAL ELEMENTS Sculptform Show
Page 55 and 56: STRUCTURAL ELEMENTS Panels & Furnit
Page 57 and 58: SHOW PREVIEW CONTINUED SUCCESS The
Page 59: Asia’s Leading Event
Page 64 and 65: EVENT CALENDAR Events Calendar 2021
Page 68: Try Canadian Wood Liên Hệ Canada
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Panels & Furniture Asia January/February 2021

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