| 摘要 |
PROBLEM TO BE SOLVED: To provide a bolt capable of managing a highly precise axial force management while suppressing the efficiency deterioration of a fastening work, and a manufacturing method for said bolt.SOLUTION: The head of a bolt is printed with a propagation time period t0 for the initial length of the bolt and arbitrarily selected information on the measurement of the time period t0.SELECTED DRAWING: Figure 1 |
