• 제목/요약/키워드: bursting test

검색결과 47건 처리시간 0.024초

슈퍼 섬유를 활용한 일체형 Shock Energy Absorber Lanyard Protection Tube 제조 및 특성분석 (Characteristic and Development of All-in-one Shock Energy Absorber Lanyard Protection Tube used Super Fibers)

  • 조진원;권상준;김상태;염정현;강지만;지병철
    • 한국염색가공학회지
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    • 제26권2호
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    • pp.106-113
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    • 2014
  • Work-related falls are a major problem in the construction and roofing industries. To avoid serious injury to the worker caused by high decelerations or forces, different systems to absorb the energy of a fall are implemented in personal protective equipment. In this study, shock energy absorber lanyard protection tube was prepared using high tenacity PET fiber, P-aramid fiber, and UHMWPE fiber, respectively. Dynamic load test and static load test, bursting strength test based on the Korea fall protection equipment standard(Korea Occupational Safety & Health Agency standard 2013-13) or conformity European safety test(CE : EN355) were conducted. Especially maximum arrest force by dynamic load test of energy absorber showed below 6,000N.

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

  • 장동욱;박종문
    • 펄프종이기술
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    • 제48권1호
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    • pp.61-66
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    • 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.

하이드로 포밍용 튜브의 성형 한계선도 측정 (Forming Limit Diagram Measurement of Tube for Tube Hydroforming Process)

  • 한수식
    • 소성∙가공
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    • 제15권6호
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    • pp.467-472
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    • 2006
  • The forming limit diagram of tube is required for the part design and the formability analysis of tube hydroforming. The finite element analyses of simple bulge test were done to obtain the various strain combinations on FLC. The finite element analysis results were shown that the bursting at various strain combinations could be induced by simple bulge test. The experiment oi tube bulge test was carried out according to the test condition that obtained from finite element analysis and the left hand side of forming limit diagram was built.

Study on the water bursting law and spatial distribution of fractures of mining overlying strata in weakly cemented strata in West China

  • Li, Yangyang;Zhang, Shichuan;Yang, Yingming;Chen, Hairui;Li, Zongkai;Ma, Qiang
    • Geomechanics and Engineering
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    • 제28권6호
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    • pp.613-624
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    • 2022
  • A study of the evolution of overburden fractures under the solid-fluid coupling state was conducted based on the geological and mining characteristics of the coal seam depth, weak strata cementation, and high-intensity mining in the mining areas of West China. These mining characteristics are key to achieving water conservation during mining or establishing groundwater reservoirs in coal mines. Based on the engineering background of the Daliuta Coal Mine, a non-hydrophilic simulation material suitable for simulating the weakly cemented rock masses in this area was developed, and a physical simulation test was carried out using a water-sand gushing test system. The study explored the spatial distribution and dynamic evolution of the fractured zone in the mining overburden under the coupling of stress and seepage. The experimental results show that the mining overburden can be vertically divided into the overall migration zone, the fracture extension zone and the collapse zone; additionally, in the horizontal direction, the mining overburden can be divided into the primary fracture zone, periodic fracture zone, and stop-fracture zone. The scope of groundwater flow in the overburden gradually expands with the mining of coal seams. When a stable water inrush channel is formed, other areas no longer generate new channels, and the unstable water inrush channels gradually close. Finally, the primary fracture area becomes the main water inrush channel for coal mines. The numerical simulation results indicate that the overlying rock breaking above the middle of the mined-out area allows the formation of the water-conducting channel. The water body will flow into the fracture extension zone with the shortest path, resulting in the occurrence of water bursting accidents in the mining face. The experimental research results provide a theoretical basis for the implementation of water conservation mining or the establishment of groundwater reservoirs in western mining areas, and this theoretical basis has considerable application and promotion value.

브레이징 접합부의 강도평가 및 고장분석 (An Analysis for Failure Mechanisms and Strength Evaluation on Brazed Joint)

  • 강기원;심희진;이병재;장경영;김정규
    • 대한기계학회논문집A
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    • 제30권10호
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    • pp.1298-1304
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    • 2006
  • The present paper is aiming at the evaluation for failure mechanisms and static strength of brazed joints used in household electronics. For these purposes, the failure analysis was performed on the various brazed joints, through the bursting, the micro-Victors hardness tests and 3-dimensional X-ray technique. The failure modes of brazed joints were classified into two different types, based on the results of bursting pressure test by means of self-designed internal-pressure testing machine. Their failure mechanism was dependent on the relationship between heat effect occurred in manufacturing process and internal flaws such as incomplete penetration and pin hole. Also, a finite element analysis was performed to evaluate the stress distribution with respect to the heat and the internal flaws.

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

  • 이용무
    • 기술표준
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    • 통권12호
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    • pp.67-78
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    • 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.

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감물염색가공에 따른 줌치한지 종이소재의 강도 변화 -감물염색가공 여부와 감물농도 차이에 따른 변화- (The Strength Properties of Jumchi-Hanji Papers Dyed with Persimmon Juice)

  • 홍희숙;김기억
    • 한국의류학회지
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    • 제42권2호
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    • pp.224-236
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    • 2018
  • This study analyzed differences between Jumchi-Hanji papers not dyed and dyed with persimmon juice (50% concentration) in five strength properties (tensile, wet tensile, tearing, bursting, and folding strengths). For the analysis, the undyed and the dyed Jumchi-Hanji papers were made by Jumchichigi during 40 minutes and made with the Dakji of different layer (a layer, two layers) and Choji method (Oebal-teugi, Ssangbal-teugi). Differences between Jumchi-Hanji papers dyed with the different concentration of persimmon juice (20% vs 70%) in the five strengths were also identified. For this examination, Jumchi-Hanji papers were made with two layer Dakji (Oebal-teugi Choji method) and by Jumchichigi during 60 minutes. Jumchi-Hanji papers made in this study were used as test samples. As a result, Jumchi-Hanji papers dyed with persimmon juice had higher tensile strength (CD), wet tensile strength (MD, CD), and bursting strength than those of undyed Jumchi-Hanji papers. However, tearing strengths (MD, CD) of dyed Jumchi-Hanji papers were lower than undyed Jumchi-Hanji papers. Folding strengths (CD) of dyed Jumchi-Hanji papers were low but the folding strengths (MD) of them were high compared to undyed Jumchi-Hanji papers. In addition, the concentration of persimmon juice influenced the five strength properties of Jumchi-Hanji. The tensile, wet tensile, and bursting strengths of Jumchi-Hanji papers dyed with a 70% concentration were higher than those one of Jumchi-Hanji papers dyed with a 30% concentration while the tearing and folding strengths of Jumchi-Hanji papers dyed with a 70% concentration were lower than Jumchi-Hanji papers dyed with a 30% concentration.

혈관결찰기의 성능평가방법으로서 혈관파열압력시험의 유용성 연구 (A Study on the Usability of the Vascular Bursting Pressure Test as a Method of Performance Evaluation of Vessel Sealing)

  • 강보람;박아름;김광택;김선태;이동혁
    • 대한의용생체공학회:의공학회지
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    • 제41권5호
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    • pp.210-218
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    • 2020
  • Vessel sealing is a medical device that converts electrical or ultrasonic energy into thermal energy and leads to seal, coagulate, and cut the vessel by protein modification within the walls or surrounding connective tissues. As most of surgeries have recently been conducted with minimally invasive surgery, the demand and market for vessel sealing are expected to get bigger. However, there is a problem that electrosurgical or ultrasonic surgical is applied and we have a high risk to evaluate the strength of seal, because the collateral and particular standards currently in force follows have not been establish. Therefore, in this study, we investigated some papers studied on the efficacy and safety of the device, the guidance of FDA and test papers previously conducted from 3 individual subject device made in Korea. We found there is a relationship between burst pressure and the performance of the device, therefore, we propose the vascular bursting pressure test for evaluating the safety and performance of the vessel sealing.

What is an Appropriate Promotion Strategy for Korean Wheat Consumption? - Find Out in the Sensory Evaluation of Rice Meal Versus Rice Containing Wheat Meal by Age Groups-

  • Kyunsik Lee;Sehwa Lim;Kyeonghoon Kim;Jinhee Park
    • 한국작물학회:학술대회논문집
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    • 한국작물학회 2022년도 추계학술대회
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    • pp.321-321
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    • 2022
  • Wheat was brought to solve food scarcity with aid from the United States caused by the Korean War. The Korean government launched a campaign to encourage mixed rice and wheat meals due to shortage of rice production in the 1960s, Wheat consumption began in earnest. However, it is difficult to rebuild the domestic wheat production base devastated by the Korean War with the technology at the time. Thus, wheat was mainly consumed from imported in the past. Since then, as wheat consumption has increased due to westernization and diversification of dietary life, wheat became the second staple grain in Korea. In this situation, the government enacted the Wheat Industry Promotion Act to create a basis for sustainable production and consumption of wheat in Korea. This study sought to improve the self-sufficiency of domestic wheat by examining the possibility of using "Ariheuk", a variety of new Korean wheat, as a rice supplement in the same context as the govemment's policy. Wheat has been used as a raw material for the processed food, such as noodles and bread. However, we approached it by using whole wheat as a nutritional grain. Participants were recruited from the agri-food consumer panel conducted by Rural Development Administration. We set a final sample of 525 consumer panels based on the age of census household heads. The experiment was conducted in such a way that participants cooked and ate 100% rice meal and rice containing 20% whole wheat meal. Participants completed the sensory evaluation questionnaire with online. For this experiment, all participants were given same whole wheat product. The sensory evaluation questionnaire consisted of color, glossiness, stickiness, aroma, chewing, sweetness, nuttiness, chewiness, softness, bursting, flavor, texture and swallowability. The sensory evaluation results were analyzed by giving -3 points to +3 points. The former points were given to the response that 100% rice meal is very superior to the response that rice containing 20% whole wheat meal. The latter points were given vice versa. Zero point was given to the response that they are similar each other. As a result, rice with 20% whole wheat meal was better than 100% rice meal in terms of color, aroma, chewiness, bursting and flavor. In case of sweetness and glossiness, there didn't exist significantly different. On the other hands, 100% rice meal was better in terms of softness and swallowability. As a result of ANOVA by age groups, from 30s or younger to 60s or more, there was significant difference among the groups in terms of color, chewiness and bursting. As a result of post-hoc analysis with Duncan's multiple range test (p < 0.05), 50s were evaluated to be significantly superior in color, chewiness and bursting compared to other age groups. In conclusion, it is appropriate to use whole wheat as a supplement to rice in order to improve the self-sufficiency of domestic wheat. As a strategy to promote domestic wheat consumption, in case of Ariheuk, it is necessary to provide an experience through whole wheat tasting and to establish a marketing strategy segmented by age groups.

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