| 摘要 |
A fastening bolt fastens flanges between a bolt head and a nut attached on the threaded portion of the shaft via spherical washers. The fastening bolt has a cavity formed within the shaft. By application of pressure in the cavity with a hydraulic fluid supplied through a hydraulic pressure port in a plug, the shaft is extended and the fastening bolt becomes unfastened condition. In the unfastened condition, a gap is created between flange and nut, and the nut and the fastening bolt are free to rotate each other, therefore, the nut can be removed easily by hand from the fastening bolt, even the bolt is large in size. The fastening force is adjustable by the width of the gap before releasing hydraulic pressure in the cavity. By releasing hydraulic pressure in the cavity, the fastened condition is obtained. Conversion between fastened condition and unfastened condition can be made quickly and easily. <IMAGE> |
