著者
臼井 俊央 齊藤 文一 田村 英樹 橋口 拓泰
出版者
一般社団法人 日本高圧力技術協会
雑誌
圧力技術 (ISSN:03870154)
巻号頁・発行日
vol.42, no.2, pp.60-68, 2004 (Released:2004-08-31)
参考文献数
8

Ballistic impact tests were conducted on intermediate purity titanium plate and Ti-6pctAl-4pctV-ELI alloy plate and newly developed Ti-Fe-O-N alloy plate using ogive-shaped projectile with 7. 62mm diameter to study relation between the fracture mechanisms and adiabatic shear band formation The plugging process was dominated by adiabatic shear deformation in localized bands. Selected data and optical micrographs relating to the adiabatic shear band formation, the variation of depth of penetration and ballistic limit velocity were presented. The fracture mechanisms associated with the shear localization and fracture process changed from bulging failure to plugging failure by a shocked pressure increase. The results showed the differences of the fracture mechanisms between two high strength titanium alloys are responsible for significant differences in the elongation of their mechanical property and in the evolution of shear band patterns It also showed evidence of the long shear band connected from the shocked surface to the bulging region was found in all target plates, but evidence of the long cracks connected did not be found in all target plates at impact velocity just near below each ballistic limits
著者
福田 忠生 尾崎 公一 山部 匡央 飯坂 元哉 早川 悌二
出版者
一般社団法人 日本高圧力技術協会
雑誌
圧力技術 (ISSN:03870154)
巻号頁・発行日
vol.49, no.3, pp.118-123, 2011-05-25 (Released:2012-01-13)
参考文献数
7

The structural behaviors and strength of actual pressure PET bottle have been investigated, mainly by experimental measurements under internal pressure. First, tensile tests of PET resin material for PET bottle were carried out in order to obtain the fundamental tensile properties and the stress-strain diagram. Then, the mechanical behaviors of PET bottle were found by strain measurements under internal pressures. Finally, burst tests were conducted for 21 PET bottles. In the present burst tests, resulted magnitudes of burst pressures were not so much scattered, within the range of 1. 9∼2. 3 MPa. Fractured shapes of bottles by bursting would be categorized in three kinds of I, L, X types. For trial, burst pressure evaluation for the bottle were made by applying the theoretical analysis of N. L. Svensson. The calculated bursting pressure and radial deflection were numerically near the experimental values. However, in further investigation for more rigorous solutions, the following items are to be studied: (1)The material properties including stress-strain diagram for the actual bi-axially oriented PET bottle itself formed by blow molding, not only PET resin material. (2)The development of analytical approach for large deformation to the range of bursting.
著者
吉田 聖一
出版者
一般社団法人 日本高圧力技術協会
雑誌
圧力技術 (ISSN:03870154)
巻号頁・発行日
vol.55, no.1, pp.31-41, 2017-01-25 (Released:2017-03-04)
参考文献数
5

On April 17, 2013, a fire and explosion occurred at the West Fertilizer Company in West, Texas, USA. The violent detonation killed 15 emergency responders and residents and injured more than 260 people. The U. S. Chemical Safety and Hazard Investigation Board (CSB) released the report on the cause of this incident. The presence of combustible materials used for construction of the fertilizer grade ammonium nitrate storage facility contributed to the progression and intensity of the fire and resulted in the detonation. This paper describes the incident based on the CSB report.
著者
西田 隆仁
出版者
一般社団法人 日本高圧力技術協会
雑誌
圧力技術 (ISSN:03870154)
巻号頁・発行日
vol.54, no.2, pp.60-72, 2016-03-25 (Released:2016-04-29)
参考文献数
48

Gaskets have been used widely in bolted flange connections in the various plants such as chemical, petroleum refining, petrochemical, power generation and so on. The prototype of gaskets had started to use in 19 century and gaskets have improved and developed for applying severe specifications conditions in a lot of industries. The role of gaskets is to prevent leakage of inner fluid from the interfaces of connections. Asbestos gaskets have been used for a long time, however, in 1980"asbestos have replaced to non-asbestos materials in the US and Europe because asbestos have affected the human health. In Japan, the new use of asbestos gaskets was completely prohibited in 2012. In the present article, the history of gaskets is described. Recently, from the environmental regulation, the quantitative measurement of a leakage has been necessary in the bolted flange connections. Thus, the higher sealing technology is needed for satisfying the severe conditions. An overview of the recent researches and trend for designing bolted flange connections are described.
著者
珠久 正憲
出版者
一般社団法人 日本高圧力技術協会
雑誌
圧力技術 (ISSN:03870154)
巻号頁・発行日
vol.28, no.1, pp.20-29, 1990-01-25 (Released:2010-08-05)
参考文献数
8

Floating oil storage system has recently been realized at Aokata Bay Area, Kamigotocho, Nagasaki, Japan.The system, which is a kind of offshore storage and suited to Japanese conditions, was proposed and developed as a new method for stockpiling emergency oil reserves since 1974.The system consists mainly of five (5) oil storage barges capable of holding abt. 880, 000kl (Total amount abt. 4.4 million kl) of crude oil, mooring dolphins, and other facilities.This paper describes special features of the oil storage barge and its mooring system.
著者
上原 陽一
出版者
一般社団法人 日本高圧力技術協会
雑誌
圧力技術 (ISSN:03870154)
巻号頁・発行日
vol.41, no.5, pp.252-263, 2003 (Released:2003-11-11)
参考文献数
12
著者
今野 彰
出版者
一般社団法人 日本高圧力技術協会
雑誌
圧力技術 (ISSN:03870154)
巻号頁・発行日
vol.41, no.6, pp.335-344, 2003 (Released:2003-12-30)
参考文献数
2

H-II launch vehicle, the large Japanese launcher placing a 4000kg class satellite into GTO, failed in the two flights of No. 5 and No. 8, after the successful 29 flights from N-I to H-II. Both failures were caused by malfunction of the cryogenic engine, the second stage engine LE-5A or first stage engine LE-7, respectively. The incidents, the causes, and the corrective actions of these failures are reported in detail in this paper. The failures brought us the precious experiences and a lot of lessons and learn. Important lessons are related with small amount of products such as a launch vehicle, which happen to fail for uneven quality by handcraft. To solve this problem, it is noted that critical manufacturing process should be distinguished to control very important characteristics of products, and that all specifications on critical processes should be determined on well-grounded technical data. In development phase, the design margin of important characteristics should be assured by testing the varied nature within defined specifications. H-IIA flew successfully in its maiden flight on August 29, 2001 to put LRE (laser Ranging Experiment) into GTO precisely. The author believes that this success results from great efforts of many engineers and researchers who learned the precious lessons of H-II failures. Rocket technology will make progress to be matured by a lot of lessons and learn from failure.
著者
亀井 浅道
出版者
一般社団法人 日本高圧力技術協会
雑誌
圧力技術 (ISSN:03870154)
巻号頁・発行日
vol.29, no.1, pp.20-28, 1991-01-25 (Released:2010-08-05)
参考文献数
2

In order to prevent leakage accidents in a oil storage tank, it is important to be acquainted with the state of deterioration. Unless the tank is maintained properly, estimation of the life may be indispensable to avoid accidents. In this paper, the life is defined as time necessary for a deepest corrosion pit on a steel plate to penetrate through the thickness.Method to predict the life are shown on the bases of statistics. Some data on corrosion rate of bottom plates are reviewed and a new interpretation about scattered values appeared in such data is introduced, which will be useful to estimate the reliability of predicted life. Extremal statistics is also reviewed to estimate the maximum corrosion depth on the outer surface of bottm plate and an usage of double exponential distribution is shown in an example for life prediction.
著者
岩舘 忠雄 田中 泰彦 竹俣 裕行
出版者
一般社団法人 日本高圧力技術協会
雑誌
圧力技術 (ISSN:03870154)
巻号頁・発行日
vol.23, no.6, pp.286-293, 1985-11-25 (Released:2010-08-05)
参考文献数
2

The high pressure reactors are sometimes autofrettaged to have the life elongated which is based on the highly compressive residual stress near the bore surface. In this study, to evaluate the material degradation based on the autofrettaged strain, the effect of autofrettage on the fracture toughness behavior was investigated using the 3.5% Ni-Cr-Mo-V steels.(1) When the prestrain increases, the fracture toughness decreases, especially in the higher yield strength steel. The decrease of the fracture toughness of the material was observed in the prestrain range larger than 5 percent for the about 1000MPa yield strength steel and than 2 percent for the about 1150 MPa yield strength steel.(2) The material resistance to ductile fracture, that is, tearing modulus TJ decreases in the same prestrain ranges as those of the fracture toughness.(3) However, the autofrettaged material taken out of the actual pressure reactor shows no decrease of the fracture toughness and the tearing modulus which is caused by the small amount of the prestrain, less than about 1 percent even in the 100 percent autofrettaged reactors.
著者
永井 敏之
出版者
一般社団法人 日本高圧力技術協会
雑誌
圧力技術 (ISSN:03870154)
巻号頁・発行日
vol.42, no.3, pp.106-114, 2004 (Released:2004-09-15)
参考文献数
4

Demand for hydrogen is rapidly growing in the current environmental approach to meeting requirements of extremely low-sulfur and increasingly light fuels. The trend toward increase in hydrogen demand is expected to be accelerated with development and commercialization of fuel cell and synthesis fuel oil which are both attracting widespread attention as clean energy technologies. The steam reforming process, which has been used as the most popular industrial hydrogen production technology, is outlined here. The life cycle assessment, which rates net emissions of greenhouse gases from the steam reforming process, is also introduced. In addition, efficient methods for increasing the capacity of the steam reforming process are explained in the light of increasing calls in recent years for revamping hydrogen plants.
著者
ラーマン エス エム モシアール 真壁 朝敏 名嘉 海人 山内 章広
出版者
一般社団法人 日本高圧力技術協会
雑誌
圧力技術 (ISSN:03870154)
巻号頁・発行日
vol.58, no.4, pp.209-215, 2020

There is a good correlation between the static strength and fatigue limit in many carbon steels. However, in the case of some commercially sold carbon steel, the fatigue limit cannot be evaluated from the static strength. Care should be taken when those materials are used for ma-chine equipment. In the case of some materials, there is decrease in fa-tigue limit from the expected values of Vickers hardness. In this study, one such case was investigated by push-pull. The examinations of the <I>S</I>-<I>N</I> curves and crack growth behavior were performed. Then, it was discussed that decrease in fatigue limit was related to the existence of inclusions or defects of unexpectedly large size. When such material as used in the present study is used for a machine equipment, the decrease of fatigue limit should be taken into account to determine an applied load.
著者
山中 啓司 菊池 務
出版者
一般社団法人 日本高圧力技術協会
雑誌
圧力技術 (ISSN:03870154)
巻号頁・発行日
vol.56, no.3, pp.136-141, 2018-05-25 (Released:2018-06-28)
参考文献数
14

After tightening a bolt, technical knowledge on how far the thread of the bolt should protrude from the nut is not organized. Therefore, in addition to the surveys of existing standards, surveys were conducted in consideration of thread strength at bolt tightening, sealing performance of flange joints, and corrosion. As a result, it was found that the protruding length of the screw thread of the bolt had little influence on the strength of the screw and the sealing performance of the flange joint. However, if it is below flush with nut face, there is a possibility of promoting corrosion by dust and moisture, so one or more protrusion lengths may be required.
著者
高木 知弘 福岡 俊道
出版者
一般社団法人 日本高圧力技術協会
雑誌
圧力技術 (ISSN:03870154)
巻号頁・発行日
vol.41, no.3, pp.106-114, 2003 (Released:2003-07-24)
参考文献数
17
被引用文献数
2

In these environmentally sensitive times, bolted flanged joint design that makes the leakage from a joint a design criterion has been investigating. However, achieving uniform bolt preload is difficult when tightening pipe flanges with a number of bolts, even if the appropriate amounts of bolt preload can be calculated following established design rules. A guideline for bolted flange joint assembly has been presented by ASME. However, the guideline needs repeated bolt-up operations to get uniform preloads. In this study, in order to establish a more effective bolt assembly guideline, numerical calculations are systematically executed by using three-dimensional finite element analysis. The analytical objects are pipe flanges of class 150lb and 300lb raised face slip-on welding type specified in JPI with a compressed asbestos sheet gasket inserted. The variations of bolt preload and contact pressure distributions at the gasket bearing surface during bolting up are estimated.
著者
森 敬祐 真壁 朝敏 安藤 新二 井上 晋一
出版者
一般社団法人 日本高圧力技術協会
雑誌
圧力技術 (ISSN:03870154)
巻号頁・発行日
vol.58, no.1, pp.14-21, 2020

Fatigue crack growth tests of rolled magnesium alloy AZ31 were performed with a side-notch plate specimen under negative mean stress conditions. In the results of the present study, even if the experimental conditions were the same, the crack growth behavior varied depending on the condition of the specimen and depending on the microstructure. The local friction between large size and small size crystals and the shear deformation are expected to be related to the crack closure. The crack growth rate was affected by the crack opening stress. When the crack growth rate was lower level, the crack closure behavior worked due to the plastic deformation and the roughness of the fracture surface. There was local rough pattern which work as the shear lip at sides of the crack surface.