| Project/Area Number |
63550123
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| Research Category |
Grant-in-Aid for General Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Research Field |
機械要素
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| Research Institution | Tokyo Metropolitan Institute of Technology |
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Principal Investigator |
KUMANO Hiroyuki Department of Mechanical Systems Engineering, Faculty of Engineering, Research Associate, 工学部, 助手 (70099331)
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| Co-Investigator(Kenkyū-buntansha) |
SAWA Toshiyuki Department of Mechanical Engineering, Faculty of Engineering, Associate Professo, 工学部, 助教授 (60107216)
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| Project Period (FY) |
1989
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| Project Status |
Completed (Fiscal Year 1989)
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| Budget Amount *help |
¥2,100,000 (Direct Cost: ¥2,100,000)
Fiscal Year 1989: ¥400,000 (Direct Cost: ¥400,000)
Fiscal Year 1988: ¥1,700,000 (Direct Cost: ¥1,700,000)
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| Keywords | Bolted Joint / Fixing Element / Thermal Change / Spring Constant / Strain Gauge / Gasket / Bolt Axial Force / Hollow Cylinder / Rectangular Plate / ひずみゲージ / 内力係数 |
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| Research Abstract |
This research deals with the characteristics of bolted Joints under thermal changes. When a bolted joint in which the coefficient of linear expansion of bolts is less than that of clamped parts is put under thermal changes, the bolt axial force produced in the bolt and the compression between the clamped parts are increased with an increase of temperature. The variations of the bolt axial force and the compression between the clamped parts are analyzed during an increase of temperature, and a formula to obtain these variations is proposed. In the experiments strain gauges for high temperature are glued to the shank of the bolt made of steel and the outer circumference of the clamped parts made of aluminum. When a bolted joint is put in a furnace, the strains of the bolt and the clamped parts are measured during an increase of temperature. The numerical results are in fairly good agreement with the experimental results.
In addition, the characteristics of a bolted joint, in which a rectangular thick plate made of aluminum was fastened at room temperature by a nut and a bolt made of steel, were examined when the joint was subjected to heat conduction. In the experiments, temperature distributions on the plate were measured with thermocouples, and an increment of bolt axial force and the maximum stress produced in the bolt due to the difference of the coefficients of linear expansion were measured by strain gauges for high temperature when one side of the thick plate was beaten and the opposite side was cooled. Using the difference method, the temperature distributions in the plate subjected to the heat conduction were analyzed. A method to obtain an increment of bolt axial force and the maximum stress produced in the bolt was proposed. The analytical results were fairly consistent with the experimental ones.
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