Lockbolt with swage collar

A fastening assembly, comprising a lockbolt, a swage collar, and a magnetic washer having a circular arc angle, wherein:

• the lockbolt comprises a lockbolt head and a shank having a diameter of d, the shank including a grip section, a groove section, and a pull section having a reverse tapered surface;
• the lockbolt head is connected to one side of the grip section;
• and an end surface of the lockbolt head is connected to one side of the shank and has a circular arc surface with a radius of R;
• the grip section is a portion of the shank close to the lockbolt head;
• the groove section is disposed on the shank and connected to the grip section;
• the groove section has a diameter of d-d/8 to d-d/16;
• the groove section is configured with offset-style radial annular groove portions and a separate axial line-style slot structure;
• the separate axial line-style slot structure has four air slots that are 90° apart;
• and the groove section has a groove depth of d/48 to d/32;
• the pull section having the reverse tapered surface is disposed on the shank and connected to the groove section;
• the pull section having the reverse tapered surface that is a conical structure, which has a reverse tapered surface angle of 3° to 8°, and is configured with a structure of annular grooves having the reverse tapered surface;
• the structure of the annular grooves having the reverse tapered surface increases the gripping force during a pulling process;
• a length of the pull section having the reverse tapered surface is reduced while the gripping force of the pull section having the reverse tapered surface remains unchanged;
• the overall length of the lockbolt is reduced;
• and a production cost is also reduced;
• the swage collar comprises a through hole that matches and is plugged with the lockbolt, a swage collar body, and a protruding edge structure;
• and
• the magnetic washer having the circular arc angle has a through hole that matches and fits onto the lockbolt;
• one side of the magnetic washer has the circular arc surface with a radius of R that engages and joins with the circular arc surface with the radius R of the lockbolt head;
• and the magnetic washer is configured to calibrate a deviation, caused by an eccentric force created during the pulling step, through the circular arc surface of the radius R thereof.