Journal of High Pressure Institute of Japan
Online ISSN : 1347-9598
Print ISSN : 0387-0154
ISSN-L : 0387-0154
Volume 32, Issue 5
Displaying 1-5 of 5 articles from this issue
  • Kazuyoshi SEKINE, Taiichirou IZUMI, Haruto SAITOH, Kunio YOSHIKAWA
    1994 Volume 32 Issue 5 Pages 240-248
    Published: September 25, 1994
    Released on J-STAGE: August 05, 2010
    JOURNAL FREE ACCESS
    This paper represents a first attempt to apply the concepts of “fractals” to assessment of statistical characteristics in industrial accident occurrence. From the fractal analysis concerning the hierarchic feature in occurrence of hazardous events, it is found that the relationship between the magnitude of damages caused by industrial accidents and their frequencies has a fractal character. As an representation for statistical risk in accident, the reisk curves, in which the exceedance frequencies that magnitude of damages exceeds some given value and its corresponding magnitude of damages are described in the log-log scale, are considered. The risk curve forms a straight line whose gradient is negative in the region of low frequencies and high magnitude of damages, so-called large scale accidents. We can reduce, from the self-simility or scaling property in accident occurrence characteristics depending on magnitude of damages, that the absolute values of slope in the risk curve give the fractal dimension D, and the D is scale invariant and also means the safety index describing the relative level of potential risk for large scale accidents. The implications of results for fractal approachs to risk curves can be proved by statistical examinations using a lot of fire accident insurance data of industrial facilities and installations in Japan.
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  • Fangyi LUO, Yong-chul PARK, Hideo KOBAYASHI
    1994 Volume 32 Issue 5 Pages 249-254
    Published: September 25, 1994
    Released on J-STAGE: August 05, 2010
    JOURNAL FREE ACCESS
    Residual stress distribution at ceramic side in Si3N4/SUS304 joint specimens were quantitatively measured by X-ray diffraction method.
    Distributions of perpendicular and parallel stresses in perpendicular and parallel directions to the interface were successfully measured. It was found that the perpendicular stress concentrated near the interface. The most dominant residual stress to the fracture of joints was considered to be the highest tensile stress at the edge of interface. Mesurement error of X-ray diffraction method was discussed. It is concluded that the X-ray diffraction method can not be used in the investigation of stress singularity near the interface, although it is effective in determining the distribution of residual stresses.
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  • Haruo YOSHIDA, Shoichi KUME
    1994 Volume 32 Issue 5 Pages 255-260
    Published: September 25, 1994
    Released on J-STAGE: August 05, 2010
    JOURNAL FREE ACCESS
    Hot isostatic pressing of cBN with Al2O3 was carried out in the thermodynamically metastable region of cBN in the phase diagram of BN. No hBN was yielded in the cBN-Al2O3 specimens HIP ped under 150MPa at 1200°C for 3hr. The specimen which had a large amount of cBN did not densify, because the pressure and temperature of the HIP condition were not so high as compared with those of the conventional very high pressure sintering condition of cBN. The specimens containing cBN up to 30vol%, however, densified to about 95% or more. The microhardness increased monotonously as cBN content increased from 0 to 30vol%. The HIP ped 30vol% cBN-70vol% Al2O3 had a vickers microhardness of above 2800 which is equal to 130% of that of sintered Al2O3. It is concluded that fabrication of high-density cBN-Al2O3 composites containing a relatively large amount of cBN, but not including hBN, is possible by HIP.
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  • Shoichi YOSHIDA, Kazuma KAWANO, Masahiko OZAKI, Tohru OHASHI
    1994 Volume 32 Issue 5 Pages 261-273
    Published: September 25, 1994
    Released on J-STAGE: August 05, 2010
    JOURNAL FREE ACCESS
    Compartmented cylindrical oil storage tanks have attracted much attention in Japan because of diversified production of oil products in petrochemical industry. The double-walled coaxial cylindrical tank is one type of compartmented tanks. This paper describes the case studies of design of the double-walled coaxial cylindrical tanks. The actual design could be simplified using some tables shown in this paper, which lead to decision of main members of the tank.
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  • Introduction of JIS B 8284
    Shozo YANAGIDA, Akira SUZUKI, Makoto AKATSU
    1994 Volume 32 Issue 5 Pages 274-279
    Published: September 25, 1994
    Released on J-STAGE: August 05, 2010
    JOURNAL FREE ACCESS
    Of the quick closure devices standardized by JIS B 8284, “Design of Quick Closure Device for Pressure Vessels”, the design calculation formulas for integral type clamps were already explained in Part 1. In Part 2 the design calculation formulas for devided type clamps are explained.
    Design calculation formulas for the devided type clamps are also given in ASME Sec. VIII. Div. 1, Appendix 24, “Design Rules for clamp connection.” However, JIS B 8284 is somewhat different in taking account of the total moment working on a flange, because JIS B 8284 deals only with self-seal type gasket for which a prior tightening force is not needed, whereas ASME rules takes a premise that the gasket tightening force is obtained by a tightening force of devided clamps.
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