• Title/Summary/Keyword: bursting strength

Search Result 64, Processing Time 0.02 seconds

Studies on the Physical Properties of Molded Packaging Material Using Rice-Straw Pulp (볏짚펄프를 이용한 성형포장재의 물성에 관한 연구)

  • Oh, Seung-Won;Kang, Chin-Ha
    • Journal of the Korean Wood Science and Technology
    • /
    • v.27 no.1
    • /
    • pp.79-87
    • /
    • 1999
  • To use the agricultural residues as the raw material of molded packaging material, the packaging trays were manufactured from rice-straw pulp. The physical properties were measured to compare non-treated trays with the addition trays, such as the addition of starch, rosin size, carboxymethyl cellulose(CMC), polyethylene glycol(PEG), alkylketene dimer(AKD), polyacryl amide(PAM). The results were as follows : 1. In the addition of starch, air permeability at addition of 5% was highest. Bursting strength and tensile strength were smaller than non-treated trays. 2. In the addition of rosin size, air permeability, bursting strength and tensile strength were smaller than non-treated trays. 3. In the addition of CMC, air permeability was higher than non-treated trays. Bursting strength and tensile strength were similar to non-treated trays. 4. In the addition of PEG, air permeability was higher than non-treated trays. Bursting strength at addition of 3% was the highest and tensile strength was smaller than non-treated trays. 5. In the addition of AKD, air permeability at addition of 1% and 5% was higher than non-treated trays. Bursting strength and tensile strength were smaller than non-treated trays. 6. In the addition of PAM, air permeability at addition of 0.01% was the highest. Tensile strength at addition of 0.01% were higher than non-treated trays. 7. The water absorption of the trays decreased with increasing adding of natural additives.

  • PDF

A Prediction of Bursting Failure in Tube Hydroforming Process Based on Necking Conditions (네킹발생조건에 의한 관재 액압성형 공정에서의 터짐 불량 예측)

  • 김상우;김정;박훈재;강범수
    • Transactions of Materials Processing
    • /
    • v.13 no.7
    • /
    • pp.629-634
    • /
    • 2004
  • Based on plastic instability, analytical prediction of bursting failure on tube hydroforming processes under combined infernal pressure and independent axial feeding is carried out. Bursting is irrecoverable phenomenon due to local instability under excessive tensile stresses. In order to predict the bursting failure, three different classical necking criteria such as diffuse necking criterion for sheet and tube, local necking criterion for sheet are introduced. The incremental theory of plasticity for anisotropic material is adopted and then the hydroforming limit and bursting failure diagram with respect to axial feeding and hydraulic pressure are presented. In addition, the influences of the material properties such as anisotropy Parameter, strain hardening exponent and strength coefficient on bursting Pressure are investigated. As results of the above approach, the hydroforming limit in view of bursting failure is verified with experimental results.

Improvement of Bonding Strength and Water Resistance of Corrugated Board (전분 접착제의 접착 효율 및 골판지의 내수성 향상을 위한 첨가제의 적용)

  • Jang, Dong-Wook;Park, Jong-Moon
    • Journal of Korea Technical Association of The Pulp and Paper Industry
    • /
    • v.48 no.1
    • /
    • pp.61-66
    • /
    • 2016
  • In order to improve the bonding efficiency of starch adhesives and water resistance of corrugated board, mixing ratio of additives dosage was changed and its effects were analyzed. When the additives dosage was increased, bonding strength, vertical compression strength, bursting strength and water resistance were increased, because of hydroxyl groups or acetyl groups in starch adhesives and cellulose fibers of corrugated board were cross-linked by additives. When 1.0% glyoxal dosage was added, flat crush strength and vertical compression strength were increased. With 1.5% glyoxal, bonding strength and bursting strength were increased. However, 2.0% glyoxal dosage was added, most of strength except bursting strength were decreased. Thus, when the appropriate amount of additives are added during corrugated board production process, increased bonding efficiency of starch adhesives and higher water resistance of corrugated board can be achieved.

Preparation and Characteristics of Leather-like Material from Shark Intestines

  • Byun Hee-Guk;Je Jae-Young;Kim Se-Kwon
    • Fisheries and Aquatic Sciences
    • /
    • v.5 no.2
    • /
    • pp.136-140
    • /
    • 2002
  • Every year fish skin, bone and intestines are discarded as processing waste material. The use of fish processing waste material is more economical and environmental-friendly. The leather-like material was produced using shark intestine. Physical charactistics such as tensile strength, elongation, tongue tearing strength, and bursting strength of the leather-like material were measured, and compared with those of a commercial leather product. The values of tensile strength, elongation, tongue tearing strength, and bursting strength of the leather-like material were $3.3kg/mm^2$, $53\%$, 13.0kg/mm and $18kg/cm^2$, respectively. Elongation $(l09\%)$ of the leather-like material coated with lacquer was higher than that of a commercial leather material, and the other factors were similar. The tensile strength and tongue tearing strength of the leather-like material was higher than those of shoes leather, but bursting strength was lower. These results suggested a potential value to use the leather-like material from shark intestines as a substitute for commercial leathers.

Effect of Back Tension in Multi-pass Drawing on the Central Bursting Defect (다단인발공정에서 후미인장응력이 중심파괴에 미치는 영향)

  • Lee, S.W.;Kim, M.C.;Shim, G.H.;Joun, M.S.
    • Transactions of Materials Processing
    • /
    • v.21 no.5
    • /
    • pp.291-297
    • /
    • 2012
  • In this paper, the effect of back tension in multi-pass drawing or wiredrawing on the central bursting defect is investigated using finite element predictions. A rigid-plastic finite element method was used together with the McClintock damage model. Central bursting defects under different back tension stress values ranging from 0% to 20% of the yield strength of the material were predicted and they were compared to understand the effect of the back tension stress values on the central bursting defect. It is found that the level of back tension has a strong influence on the cumulative damage. Thus, higher back tension raises the possibility of the central bursting defect occurring, even though it decreases the interfacial pressure between the die and the work piece.

A Study of the Physical Properties of Weft Knit Fabrics (위편조직(緯編組織)의 물성(物性)에 관한 연구(硏究))

  • Kim, In-Suk;Lee, Soon-Hong
    • Journal of Fashion Business
    • /
    • v.2 no.4
    • /
    • pp.93-101
    • /
    • 1998
  • Knit products which had been limited only to underwear, recently became popularized, fashionized and highly classified covering even outer garments such as sportswear like golfwear, woman's dress, and man' s suit. As fashion cycle is getting shorter and the more a nation advanced prefers knit to woven fabrics knit industry has a very bright prospect, particularly woman's knit which is sensitive to fashion can be said as a fashion product with high value added. This study is to grasp the physical properties of stitch which are fundamental to the development of knit products. For this purpose, 2/20s of 100% wool were woven by the author of this study to basic plain stitch, rib stitch, varied transfer stitch, and float stitch on a SEMASEIKI cross knitter 7G to test the physical properties, and the result was as follows; 1. As for the relation between knit stitch and rate of extension recovery, rate of extension recovery was higher in the course direction than in the wale direction of three stitches except transfer stitch; rib stitch showed the highest rate of extension recovery in the course direction while float stitch showed the highest rate of extension recovery in the wale direction. 2. As for the relation between knit stitch and bursting strength elastic rib stitch showed higher bursting strength to indicate elasticity is an important factor of bursting strength and float stitch showed higher bursting strength too to indicate that the floating yarn on the surface plays a role of support. 3. As for the relation between knit stitch and air permeability perforated transfer stitch showed the lowest air permeability to prove that the size of perforation affects on the air permeability a great deal. 4. As for the relation between knit stitch and warmth retaining rib stitch through two lined needle bar showed the highest degree. The reason the warmth of perforated transfer stitch didn't decrease much was because the perforation wasn't big enough and content of air increased from the unevenness of the perforated parts through stitch variation. Based upon this result, each stitch can be characteristically summarized as follows; plain stitch showed a stable condition of knit cloth in four kinds of physical property test. And rib stitch is proper to tighten the edge of sleeve or clothe making use of its excellent extension recovery and to make socks for the highest bursting strength and warmth retaining. In the case of transfer stitch, seasonable designs can be taken by controlling the size of loop. Considering the pleasantness, underwear should be made of stitches with good air permeability float stitch was revealed to have color and pattern effects and a great bursting strength. This study has limitations in the aspect that it dealed with a small part of various knit stitches and the items of physical property test were not enough. The author of this study hopes that further studies would make deeper understandings about knit stitch based on more varied stitches and physical property tests ultimately to contribute to the development of fashionable designs proper to maximize the usage, function and originality.

  • PDF

A Study on the KS standardization of functional corrugated fibreboard (기능성 골판지 포장재 KS규격표준화연구)

  • Lee, Yong-Mu
    • The Monthly Technology and Standards
    • /
    • s.12
    • /
    • pp.67-78
    • /
    • 2003
  • In order to keep a characteristic corrugated fibreboard of fruits and flowers, temperature and humidity change of corrugated fibreboard are analyzed. According to relative humidity rises at fixed temperature, bursting strength of corrugated fibreboard was fallen and double wall corrugated fibreboard appeared greatly the bursting strength decline rate than double faced corrugated fibreboard and edgewise compressive strength of paper more than humidity 80% in rapidly fall. A column crush test of paper became decrease in the high temperature and ordinary temperature strength did over humidity 70% rapidly fallen and strength decrease happened by low temperature 80% slowly fallen and later rapidly. According to ISO standard temperature humidity conditioning (23$\pm$2 , 50$\pm$2%) change, pulp composition difference as to the ring crush strength of a physical strength and generally compare to KS standard increased 5∼8% for the compressive strength, and wet strength reagent was increased 4% inside and out.

  • PDF

Experimental Analysis of Anchorage Zone Design for Unbonded Post-Tensioned Concrete Beam With 2400MPa Single Tendons (2400MPa 단일 강연선이 적용된 포스트텐션 정착 구역 설계에 대한 실험적 연구)

  • Moon, Sang Pil;Ro, Kyong Min;Kim, Min Sook;Lee, Young Hak
    • Journal of Korean Association for Spatial Structures
    • /
    • v.20 no.1
    • /
    • pp.41-48
    • /
    • 2020
  • In this study, the design of anchorage zone for unbonded post-tensioned concrete beam with single tendons of ultimate strength 2400MPa was evaluated to verify that the KDS 14 20 60(2016) and KHBDC 2010 codes are applicable. The experimental results showed that the bursting force equation of current design codes underestimated bursting stress measured by test, because the KDS 14 20 60(2016) and KHBDC 2010 propose the location of the maximum bursting force 0.5h which is the half of the height of member regardless of stress contribution. Although the allowable bearing force calculated by current design codes was not satisfied the prestressing force, the cracks and failure in anchorage zone was not observed due to the strengthening effect of anchorage zone reinforcement.

A Study of strength properties of Deinked pulp according to deinking agents (탈묵제에 따른 탈묵 펄프의 강도적 성질에 대한 연구)

  • 손성민;김성빈;김현성
    • Journal of the Korean Graphic Arts Communication Society
    • /
    • v.18 no.1
    • /
    • pp.95-102
    • /
    • 2000
  • This paper presents the second part of a study of deinking using wort. Physical properties of deinked pulps such as tensile strength, bursting strength and tearing resistance were investigated. In order to analyze the properties, the fiber length and coarseness of deinked pulp was also measured. Results of deinking experiments showed that the deinking efficiency of enzyme treatments was higher than that of chemical treatments in strength properties such as tensile strength, bursting strength and tearing resistance on the the whole. we think that the reason why is that the fiber length and coarseness of deinked pulp with wort are more increased and decreased than those of deinked pulp with chemicals individually.

  • PDF

Studies on Linerboard Compositions of Corrugated Fiberboard Boxes for Oriental Melons (참외 포장용 골판지상자의 재질구성에 관한 연구)

  • Ha, Young-Sun;Lee, Jun-Ho;Kim, Su-Il;Park, Nam-Ho
    • Food Science and Preservation
    • /
    • v.7 no.2
    • /
    • pp.160-165
    • /
    • 2000
  • The study aimed to review linerboard compositions of corrugated fiberboard boxes for Oriental melons(Cucumis melon L. var makuwa), analyzing relationships among material compositions, price, weight of boxes, theoretical compression and bursting strength of various liner boards. 19 and 22 different liner boards were currently used for the bleached and the unbleached corrugated boards, respectively. The corrugated board containers with the bleached liners were mostly used in the market although the average price was 10 percents higher than the unbleached. The average compression strength of the bleached. We strongly recommend to redesign the boxes because the average compression and bursting strength of the current boxes were much higher than national packaging standards as much as 70 and 82, respectively.

  • PDF