| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a bolt axial force setting method capable of stably setting the bolt to a prescribed axial force when members are fastened with bolt and nut.SOLUTION: A cylindrical bolt 10 formed with a male thread 10A at its outer circumferential surface is heated, a stress rod 11 is inserted into the cylindrical bolt, both ends of the stress rod are fixed to the cylindrical bolt with a jig 12, and then a temperature of the cylindrical bolt is returned back to a room temperature, an axial tensile force acts on the cylindrical bolt by the stress rod, a pair of nuts 15 are threadably engaged with the outer circumferential surface of the cylindrical bolt and members 13, 14 are held between the pair of nuts, the jig is removed, the axial tensile force of the stress rod is released and the cylindrical bolt is shrunk so as to control the cylindrical bolt to a prescribed axial force. It is also applicable that the stress rod is cooled and set to the cylindrical bolt and its temperature is returned to a room temperature.</p> |
