Manufacturer Technology of Dense Chinese Fir Laminated Veneer Lumber (LVL)

2012 ◽  
Vol 542-543 ◽  
pp. 363-366
Author(s):  
Chi Qiang Yao ◽  
Li Yu ◽  
Yan Jun Li ◽  
Shi Ke Xu ◽  
Lan Xing Du
Keyword(s):  
Mechanical Properties ◽  
Hot Pressing ◽  
Phenol Formaldehyde ◽  
Chinese Fir ◽  
Water Soluble ◽  
Technological Parameters ◽  
Pressing Temperature ◽  
Laminated Veneer Lumber ◽  
Pressing Time ◽  
Processing Factors

Dense Chinese Fir LVL was manufactured from Chinese Fir veneer which was impregnated with laboratory prepared water soluble phenol formaldehyde(PF) resin. The influences of various processing factors on properties of dense Chinese Fir LVL were explored. It is showed that the mechanical properties of dense Chinese Fir LVL first increase and then decrease with the increase of drying temperature and hot-pressing time. Plank performance becomes higher with the increase of compressibility and hot-pressing temperature. The optimum technological parameters for LVL process are set.

A Study on Sliced Bamboo Veneer-Chinese Fir Glulam Composite Panel

2010 ◽  
Vol 168-170 ◽  
pp. 2033-2036
Author(s):  
Chun Gui Du
Keyword(s):  
Hot Pressing ◽  
Chinese Fir ◽  
Woven Fabric ◽  
Composite Panel ◽  
Bottom Surface ◽  
Technological Parameters ◽  
Surface Color ◽  
Pressing Temperature ◽  
Pressing Time ◽  
Unit Pressure

Previous studies have indicated that Chinese fir glulam has many defects on surface: color is singleness, knot is more, surface is roughness, etc. This paper presents a study on the manufacturing technology of sliced bamboo veneer-Chinese fir glulam composite panel. Sliced bamboo veneer were glued on both the top and bottom surface of Chinese fir glulam. The results showed: (1)sliced bamboo veneer can beautify the surface of Chinese fir glulam; (2)sliced bamboo veneer should directly overlay on the surface of Chinese fir glulam, and it is not suitable back lining non-woven fabric in gluing; (3)the optimal composite technological parameters are: unit pressure: 0.7MPa; hot pressing temperature: 100°C; hot pressing time: 4min.

Study on the Technology and Properties of Soybean Adhesive Bonded Laminated Veneer Lumber from Poplar Wood

2012 ◽  
Vol 174-177 ◽  
pp. 847-851
Author(s):  
Wen Ding Li ◽  
Yang Zhang ◽  
Cong Liu ◽  
Kien Nguyentrong ◽  
Chong Jia
Keyword(s):  
Mechanical Properties ◽  
Hot Pressing ◽  
Modulus Of Rupture ◽  
Poplar Wood ◽  
Horizontal Shear ◽  
Pressing Temperature ◽  
Laminated Veneer Lumber ◽  
Pressing Time ◽  
Mechanical And Physical Properties ◽  
The Mean

It was investigated that the technology of hot prepressing temperature and hot pressing duration had influence on the mechanical and physical properties of soybean adhesive bonded laminated veneer lumber(LVL) from poplar wood. The results show that lower mat prepressing temperature may be beneficial to the mechanical properties of LVL. The effects of hot pressing duration on the properties of LVL are less than those of prepressing temperature. When the prepressing temperature is 70°C and hot pressing time is 100s/mm with glue spread amount of 450g/m2, hot pressing temperature of 160°C and mat pressure of 1.6 MPa, the mean modulus of rupture value is 78 MPa, mean modulus of elasticity value is 14.4 GPa, mean horizontal shear strength value is 7.8 MPa and immersion peel rate is 0.4%, respectively.

scholarly journals Environmentally-Friendly High-Density Polyethylene-Bonded Plywood Panels

Polymers ◽  
2019 ◽  
Vol 11 (7) ◽  
pp. 1166 ◽  
Author(s):  
Pavlo Bekhta ◽  
Ján Sedliačik
Keyword(s):  
Mechanical Properties ◽  
Hot Pressing ◽  
High Density Polyethylene ◽  
Phenol Formaldehyde ◽  
Urea Formaldehyde ◽  
Physical And Mechanical Properties ◽  
Core Layer ◽  
High Density ◽  
Pressing Pressure ◽  
Pressing Time

Thermoplastic films exhibit good potential to be used as adhesives for the production of veneer-based composites. This work presents the first effort to develop and evaluate composites based on alder veneers and high-density polyethylene (HDPE) film. The effects of hot-pressing temperature (140, 160, and 180 °C), hot-pressing pressure (0.8, 1.2, and 1.6 MPa), hot-pressing time (1, 2, 3, and 5 min), and type of adhesives on the physical and mechanical properties of alder plywood panels were investigated. The effects of these variables on the core-layer temperature during the hot pressing of multiplywood panels using various adhesives were also studied. Three types of adhesives were used: urea–formaldehyde (UF), phenol–formaldehyde (PF), and HDPE film. UF and PF adhesives were used for the comparison. The findings of this work indicate that formaldehyde-free HDPE film adhesive gave values of mechanical properties of alder plywood panels that are comparable to those obtained with traditional UF and PF adhesives, even though the adhesive dosage and pressing pressure were lower than when UF and PF adhesives were used. The obtained bonding strength values of HDPE-bonded alder plywood panels ranged from 0.74 to 2.38 MPa and met the European Standard EN 314-2 for Class 1 plywood. The optimum conditions for the bonding of HDPE plywood were 160 °C, 0.8 MPa, and 3 min.

Production Process and Nondestructive Testing of Soybean Stalks Particleboard

2012 ◽  
Vol 430-432 ◽  
pp. 1339-1342
Author(s):  
Wei Lu ◽  
Jia Yao ◽  
Ping Han ◽  
Wan Jiang Wu ◽  
Chuang Liu
Keyword(s):  
Mechanical Properties ◽  
Hot Pressing ◽  
Time Distribution ◽  
Process Analysis ◽  
Orthogonal Experiment ◽  
Flexural Vibration ◽  
Modulus Of Rupture ◽  
Process Conditions ◽  
Pressing Temperature ◽  
Pressing Time

Orthogonal experiment of four factor and three level has been adopted, through the process analysis of the various factors on mechanical properties, the best process conditions of soybean stalks particleboard are chosen as: density is 0.7g/cm3, glue content is 12%, and hot pressing time distribution is 3+4 minutes, hot pressing temperature is 175°C. The Ef (the dynamic elastic modulus of NDT) of soybean stalks particleboard has been examined by flexural vibration method of FFT(Fast Fourier Transform), the regression between Ef and MOE(modulus of elasticity), MOR(modulus of rupture) is significant and existing high relevance degree, so using FFT method for NDT of composite materials is feasible.

Fabrication and Mechanical Properties Analysis of Flame-Retardant Fiberboards Made of Abandoned Flax Fibers and Polyurethanes

2012 ◽  
Vol 627 ◽  
pp. 892-895 ◽  
Author(s):  
Li Hua Lv ◽  
Min Zuo ◽  
Chun Yan Wei ◽  
Xiao Wang ◽  
Ke Wang
Keyword(s):  
Mechanical Properties ◽  
Flame Retardant ◽  
Hot Pressing ◽  
Mass Fraction ◽  
Bending Strength ◽  
Range Analysis ◽  
Pressing Temperature ◽  
Limiting Oxygen Index ◽  
Flax Fibers ◽  
Pressing Time

In this paper, abandoned flax fibers were adopted as reinforcing materials, polyurethane particles were adopted as matrix materials. Through blend mastication and hot-pressing methods to exploit flame-retardant fiberboards, which were made of abandoned flax fibers and polyurethanes. This paper explored the mechanical properties and flame-retardant property.Tensile strength, bending strength and impact strength were selected as mechanical properties' test index, limiting oxygen index was selected as flame-retardant property's test index. Abandoned flax fibers mass fraction, hot-pressing temperature, hot-pressing time and flame-retardant mass fraction acted as level of factor. The optimized processing conditions were concluded through orthogonal experiment and the range analysis: abandoned flax fibers mass fraction 45%, hot-pressing temperature 170°C, hot-pressing time 6 min, flame-retardant mass fraction 10%. This paper studied the solution of the abandoned fibers’ reuse. At the same time, it provided theoretical guidance for the further development of flame- retardant polyurethane fiberboard.

An Environmentally Friendly Composite Composed of Short-Cut Grass and Starch

2014 ◽  
Vol 525 ◽  
pp. 3-6
Author(s):  
Chuan Bao Wu ◽  
Xiang Hui Zeng
Keyword(s):  
Tensile Strength ◽  
Hot Pressing ◽  
Raw Materials ◽  
Environmentally Friendly ◽  
Tensile Fracture ◽  
Water Medium ◽  
Pressing Temperature ◽  
Pressing Method ◽  
Pressing Time ◽  
Processing Factors

Short-cut grass and starch were selected as raw materials to prepare environmentally friendly composite by hot-pressing method. Results indicated that short-cut grass and starch were easily mixed uniformly by water medium and adapt to hot-pressing process. Hot-pressing time and hot-pressing temperature influenced the performances of composites. The strength and elongation first increase and then decrease with the increase of two processing factors. Tensile strength and strength at fracture reach 2.3 MPa and 1.2 MPa respectively when hot-pressing was performed at 140 °C for 10 min. The tensile strength is always higher than strength at tensile fracture and the elongation at fracture is always higher than that at maximum force. This indicates that the fracture of composite is ductile fracture. The hardness of composite is uneven. Long hot-pressing time resulted in not too obvious decrease of hardness.

Study on the Effect of Impregnation Process on Physical and Mechanical Properties of Chinese Fir LVL

2013 ◽  
Vol 753-755 ◽  
pp. 848-852
Author(s):  
Yu Cheng Shen ◽  
Li Ping Yin ◽  
Cheng Jian Huang ◽  
Chi Qiang Yao ◽  
Li Yu ◽  
...  
Keyword(s):  
Weight Gain ◽  
Phenol Formaldehyde ◽  
Physical And Mechanical Properties ◽  
Chinese Fir ◽  
Water Soluble ◽  
Low Molecular Weight ◽  
Laminated Veneer Lumber ◽  
Mechanical And Physical Properties ◽  
Wet Weight ◽  
Temperature And Pressure

Laminated veneer lumber (LVL) was manufactured from Chinese fir, which had been impregnated with laboratory prepared low-molecular-weight water-soluble phenol formaldehyde (PF) resin. The effects on the mechanical and physical properties of the LVL were investigated which made from veneer that had been subjected to various levels of the resin treatment. The results showed that either under conditions of normal temperature and pressure, or at increased pressure, the weight gain would increase with the impregnating time. Under the same impregnation technology, along with the increase of resin concentration, dry weigh gain increased, wet weight gain first increased and then decreased. Density of LVL increased, TS reduced, MOR and MOE first increased and then decreased as the weight gain increased.

Process and Mechanical Properties of Basalt Fiber/Polylactic Acid Composites

2012 ◽  
Vol 193-194 ◽  
pp. 329-332 ◽  
Author(s):  
Li Hua Lv ◽  
Gui Bin Liu ◽  
Dan Zhou
Keyword(s):  
Mechanical Properties ◽  
Polylactic Acid ◽  
Hot Pressing ◽  
Mass Fraction ◽  
Bending Strength ◽  
Matrix Material ◽  
Basalt Fiber ◽  
Pressing Pressure ◽  
Pressing Temperature ◽  
Pressing Time

In this paper, the basalt fiber/polylactic acid composites were prepared by laying-up hot-pressing process, using PLA sheet as the matrix material and basalt fiber fabrics as the reinforced material, besides, the mechanical properties were studied and the parameters of hot-pressing were optimized. PLA mass fraction, heat pressing temperature, heat pressing pressure and heat pressing time were selected as the four main influence factors and tensile strength and bending strength were taken as the test indexes, the best processing conditions: PLA mass fraction 63%, Heat pressing temperature 195 °C, Heat pressing pressure 7MPa, Heat pressing time 10min were optimized through orthogonal experiment and range analysis. The significance of the study was providing theoretical guidance for the further development of high-performance basalt fiber composites.

Investigation of Furfural Formation and Mechanical Properties of Suberinic Acids-Bonded Particleboards Depending on their Preparation Parameters

2021 ◽  
Vol 903 ◽  
pp. 235-240
Author(s):  
Raimonds Makars ◽  
Daniela Godiņa ◽  
Janis Rizhikovs ◽  
Aigars Paze ◽  
Ramunas Tupciauskas ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Hot Pressing ◽  
High Performance ◽  
Bending Strength ◽  
Ph Value ◽  
Raw Material ◽  
Technological Parameters ◽  
Pressing Temperature ◽  
Outer Bark ◽  
Wood Particles

Silver birch (Betula pendula) outer bark suberin can be used as a raw material to make an adhesive for particleboards (PBs). It is a promising formaldehyde-free alternative to traditional synthetic resins. However, the adhesive is acidic, which can catalyse furfural (FUR) formation from xylans in wood particles that are used for the preparation of PBs. FUR being a volatile organic compound can be emitted from the PBs and exposure to it can have harmful effects on humans. In the scope of this study, the effects on technological parameters (wet adhesive pH: 3, 6 and 9), glycerol as an additive to adhesive and hot-pressing temperature (180...230 °C) were investigated on the FUR formation in PBs. The FUR content was determined with high-performance liquid chromatography-ultraviolet spectroscopy system from the extracts of milled PBs. Mechanical properties (modulus of elasticity, bending strength, and thickness swelling) of the PBs were also studied. When using an adhesive with a pH 6 at hot-pressing temperature 230 °C with no glycerol added, it was possible to obtain PBs that satisfied the requirements of EN 312 P2 (boards for interior fitments). The FUR yield of these boards were more than 6 times lower than for the PBs pressed at 230 °C with a wet adhesive pH value 3.

Investigation of Formaldehyde-Free Soybean Meal-Based Adhesive Applying on Particleboard

2010 ◽  
Vol 113-116 ◽  
pp. 2085-2089
Author(s):  
Qiang Gao ◽  
Yao Hui Dong ◽  
Shi Feng Zhang ◽  
Jian Zhang Li
Keyword(s):  
Mechanical Properties ◽  
Moisture Content ◽  
Thermal Behavior ◽  
Soybean Meal ◽  
Hot Pressing ◽  
National Standards ◽  
Pressing Temperature ◽  
Technical Parameters ◽  
Pressing Time ◽  
Environmental Friendly

For manufacturing high mechanical properties and environmental-friendly particleboard, a formaldehyde-free soybean meal (SM)-based adhesive was developed and applied in the mechanical manufacture of particleboard. The thermal behavior of the adhesive was investigated and the properties of the particleboard were tested according to Chinese Standards methods. The results show that the optimum technical parameters were: hot-pressing temperature was 180 °C, hot-pressing time was 65 s/mm, moisture content was 12 %, and glue content was 15 %. The MOR and IB of particleboard were 20.6 MPa and 0.59 MPa respectively. It fully fits the Chinese National Standards GBT 4897.5-2003. Therefore, it is a practical way for manufacturing environmental friendly particleboard by SM-based adhesive.

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