Technician A says torque-to-yield bolts are often one-time-use fasteners. Technician B says that torque-to-yield bolts will usually have a tightening specification that calls for a certain torque, and then a number of degrees further. Who is correct?
A) A only
B) B only
C) Both A & B
D) Neither A nor B
Answer (2)
Both Technician A and Technician B are correct regarding torque-to-yield bolts. These bolts are often one-time-use due to their design, and they also have tightening specifications that include a torque value followed by an angle of rotation. Thus, the answer is C) Both A & B.
;
To answer this question, let's first understand what torque-to-yield (TTY) bolts are. Torque-to-yield bolts are a type of fastener that is stretched into its plastic deformation zone when installed, meaning they are tightened past their elastic limit and deformed permanently to achieve a more uniform clamping force. This is done through a specific tightening procedure.
Technician A's statement : Torque-to-yield bolts are often considered one-time-use fasteners. This is because once they have been stretched beyond their elastic limit, reusing them could lead to inadequate clamping force, potential failure, and damage to the components being fastened. Therefore, Technician A is correct in stating that TTY bolts are usually a single-use component.
Technician B's statement : These bolts usually have a tightening specification that involves applying an initial torque to a specific value, and then turning the bolt a further number of degrees. This method ensures precision and consistency in applying the necessary tension to achieve the desired clamp load without over-stressing the bolt. Therefore, Technician B's statement is also correct.
Given this information, both Technicians A and B are correct . Technician A correctly notes their single-use nature, and Technician B correctly describes the tightening procedure.
Therefore, the correct answer is: C) Both A & B .
