fig1 to a second position where the piercing tip 28 of the rod 48 is moved into the socket 42 the actuator and heat source 54 also heats the piercing tip 28 when the piercing tip is in the second position the actuator and heat source 54 communicates with a torque sensing device 56 in the wrench device tool 46 and is controlled to move the piercing tip 28 from the first position to the second position in response to the torque sensing device 56 sensing the nut 14 being turned on the bolt 16 to the predetermined preload torque fig3 is a representation of the method of using the apparatus 12 to torque the nut 14 on the bolt 16 of the fastener assembly 10 to a preload torque and then deforming the fastener assembly 10 to hold the preload torque as represented in fig3 the wrench device 26 and the wrench device socket 42 are moved axially toward the nut 14 and bolt 16 fastener assembly 10 until the nut 14 is received in the socket 42 the socket engagement surfaces 44 are positioned around the nut 14 with at least two of the engagement surfaces 44 engaging with opposite side surfaces 22 of the nut 14 the wrench device socket 42 is then rotated to tighten the.