To eliminate the disadvantages that the efficiency of whole inspection work for checking for fastening and fixation of bolts and nuts is reduced and personnel expenses required for the inspection are increased because there are sections where workers forget to fasten bolts and nuts or tighten them insufficiently during work in the connection work of structures having a specified size by use of a large number of bolts and nuts and, therefore, a person in charge of inspection confirms them by touching them one by one with his hand to achieve complete connection and fixation of bolts and nuts.
The following function is added to the bolts and nuts connecting a plurality of structures having a specified size and a fixed fastening width. When a plurality of structures having the specified size are securely connected and fixed by the bolts and nuts, a mark drawn by fluorescent ink and indicating that secure connection and fixation are done is attached to a bolt face in a rear part of the nut in advance so that the mark appears at the minimum width that allows confirmation visually or by equipment.
| JP2014181976 | BOLT LOOSENESS MONITORING DEVICE OF SWIVEL TYPE BOOM WORK MACHINE |
| WO/2012/040800 | SECURITY BOLT |
OGAWA TAKASHI
FUSE HIROHIDE
NISHIMURA KENJI
FUSE HIROHIDE