• Journal of the Korea Furniture Society
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• v.28 no.1
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• pp.53-59
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• 2017

Wooden dowels are commonly used to join the particleboard members together in many types of structures, But little information is available concerning their holding properties in domestic particleboard. This study was performed to determine the withdrawal loads and strengths on the effect of diameter of dowel and hole clearance. The test block was manufactured from 15 mm thick domestic particleboard. The dowel was manufactured 6, 8 and 10 mm diameters from korean castanea, korean pine and tuliptree. Research reported here indicates that withdrawal loads increase, but withdrawal strengths decrease, as the dowel diameter increases. This study also indicates that dowel withholding load and strength for particleboard less decrease than those for domestic wood as a hole clearance decreases.

• Journal of the Korean Wood Science and Technology
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• v.19 no.4
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• pp.43-51
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• 1991

This study was carried out to determine the withdrawal strength of various screws according to root diameter of screw and embeded length on the face and edge of domestic particleboard and medium density fiberboard. The obtained results were as follows: 1. The withdrawal strength of screw in domestic particleboard and medium density fiberboard was closely related to embeded length of the screw but less dependent on root diameter of the screw. 2. The withdrawal strength on the face and edge of domestic particleboard could be predicted by means of the following expression: $F_{Pf}=4.60{\times}D^{0.24}{\times}L^{1.14}(R^2=0.87)$ $F_{Pe}=0.54{\times}D^{0.43}{\times}L^{1.73}(R^2=0.84)$ Where: $F_{Pf}$ : withdrawal strength on the face of particleboard(kgf) $F_{Pe}$=withdrawal strength on the edge of particleboard(kgf) D=diameter of the screw(mm) L=embeded length(mm) 3. The withdrawal strength on the face and edge of domestic medium density fiberboard could he predicted by means of the following expression: $FM_f=1.53{\times}D^{0.53}{\times}L^{1.39}(R^2=0.93)$ $F_{Me}=1.14{\times}D^{0.66}{\times}L^{1.36}(R^2=0.87)$ where: $F_{Mf}$ = withdrawal strength on the face of medium density fiberboard(kgf) $F_{Mf}$=withdrawal strength on the edge of medium density fiberboard(kgf).

• Journal of the Korean Wood Science and Technology
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• v.19 no.3
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• pp.27-34
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• 1991

Screw withdrawal test was carried out on the face and edge of domestic particleboard and medium density fiberboard in order to evaluate optimum pilot hole diameter. The obtained results were as follows: 1. Maximum withdrawal strengths on the face and edge of particleboard were obtained with pilot hole diameters at about 50% of root diameters of screw. 2. Maximum withdrawal strength on the face and edge of medium density fiberboard were obtained with pilot hole diameters that were about 60% and 50% of root diameters of screw, respectively. 3. Withdrawal strength showed about 91% of maximum withdrawal strength when pilot holes were not pre bored at particleboard. but when pilot holes at 90% of root diameter of screw withdrawal strength showed about as 51.3% of maximum withdrawal strength. 4. Withdrawal strength showed about 88% of maximum strength when pilot holes were not used, but withdrawal strength indicated 55.4% of maximum strength in case of 90% of root diameters of screw. 5. Maximum withdrawal strength on the face of particleboard was about 70.5% higher than that of the edge, and however medium density fiberboard was about 19.6% higher than that of the edge.

• Journal of the Korean Wood Science and Technology
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• v.18 no.2
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• pp.67-78
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• 1990

This study was performed to determine the characteristics of physical and mechanical properties of domestic wood based materials; plywood, particleboard, medium density fiberboard. Main items of tested properties were panel size, moisture content, water absorption, linear expansion and thickness swelling, glue bond shear strength, bending properties(stress at proportional limit, modulus of rupture. modulus of elasticity), tensile strength, screw holding strength, and internal bond as neccessary. the results were discussed mainly with Korean Standards. The obtained conclusions are as follows; 1. Length and width of 3mm thin plywood(3-ply) and 12mm thick plywood(7-ply) were satished with KS-standard, but thicknesses of these panels were not- passed tolerance limit except one of eight makers. 2. Length and width of particleboard and medium density fiberboard were greater than the tolerance limit value of KS standard, but the thicknesses of these panels were passed this value. 3. Moisture contents of 12mm thick and 3mm thin plywood were satisfied with KS-standard except one mill made 3mm thin plywood. 4. Moisture absortion of plywood was not passed tolerance limit of KS-standard but particleboard was satisfied with this standard value. 5. Dry and wet shear strengths in glue bond of 3mm thin plywood were not reached to KS-standard, but those of 12mm thick plywood were sufficiently satisfied with KS standrad. 6. Modulus of ruptures, parallel to grain and perpendicular to grain of plywood, and particleboard and medium density fiberboard were satisfied with KS-standard. 7. Tensile strengths, parallel to grain and perpendicular to grain of plywood were satisfied with allowance stress of US product standard PS 1-74. 8. Screw holding strength of particleboard was not reached to KS standard, but internal bond was satisfied with KS standard.

• Journal of the Korean Wood Science and Technology
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• v.30 no.4
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• pp.23-26
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• 2002

The generation of wastewood is currently about 40% level of the amount of domestic wood use. When the rate of wood self-supply is considered, the recycling of wastewood in wood panel products industry should be encouraged. This study was evaluated the performance of particleboard (PB) made from wastewood. PBs were manufactured with the synthesized urea-formaldehyde resin at 5 minutes hot-press time, and at 162℃ press temperature with 6 percent resin solids level on an ovendry wastewood particle weight basis. The PBs were tested by the procedure of ASTM D 1037. Test results exceeded the minimum strength requirement according to KS F 3104 Particleboard type 8.0. The PB's performance showed that wastewood is suitable raw material for PB.

• Journal of the Korean Wood Science and Technology
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• v.45 no.5
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• pp.613-621
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• 2017

This study was performed to determine the withdrawal loads and strengths on the effect of dried wooden dowel. The test block was manufactured from 15 mm thick domestic wood and particleboard. Dowels of 6, 8 and 10 mm in diameter are made of korean castanea, korean pine and tulip wood. Research reported here indicates that withdrawal loads increase, but withdrawal strengths decrease, as the dowel diameter increases. This study also indicates that withdrawal load and strength of dried wooden dowel showed over 10% increase compared to those of normal conditioned dowel. However, there was an exception for the case of korean pine test block with dried tulip wood dowel. Meanwhile, the dried wooden dowel withdrawal loads and strengths for particleboard test blocks show 6~14.4% and 6.2~18.2% increase, compared to those of normal conditioned dowel, respectively.

• Journal of Korean Society of Forest Science
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• v.96 no.1
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• pp.54-57
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• 2007

Urea-formaldehyde (UF) resin was formulated similarly to plywood resin in the laboratory. The synthesized UF resin adhesive was mixed with extender, filler and acid catalyst. The mixture contained 56.1% total solids and 43.9% water. The mixes was used to bond five Com-Ply types using Korean wood species. The Com-Ply made were tested for shear strength and wood failure according to KS F 3101 ordinary plywood as well as for bending strength per KS F 3104 particleboard. The performance test results showed good strength properties for all Com-Ply types made in this study. This result represented that the UF resin adhesive mix was adequate for bonding Com-Ply with domestic wood species.

• Journal of Korean Society of Forest Science
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• v.104 no.2
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• pp.254-260
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• 2015

This paper assesses the tariff reduction on imported wood products that will have impact on the demand for domestic wood products in South Korea, by estimating the Armington substitution elasticities based on the assumption that they are imperfect substitutes. Results indicate that domestic and foreign wood products are far from perfect substitutes to each other. The substitution elasticities in plywood and fiberboard appeared to be high, implying that tariff reduction may have negative effects on those industries. On the contrary, imported and domestic particleboard showed a low substitution elasticity. The decline of fiberboard industry may lead to the decline in forestry since fiberboard is produced mainly by thinned woods supplied from domestic forests. Therefore, effective countermeasures to enhance the competitiveness of wood products industry are needed to cope with the market opening.