(a)Test procedure. (1) Each test sample shall be an assembly
consisting of a fastening with a locking device. Each standard sample shall
be an assembly consisting of a fastening with a lockwasher.
(2) Five standard samples and five test samples shall be
(3) Each standard and test sample shall use a new
fastening of the same specifications as being used on the motor assembly.
(4) A new tapped hole shall be used for each standard and
test sample. The hole shall be of the same specifications as used on the
(5) Each standard and test sample shall be inserted in the
tapped hole and continuously and uniformly tightened at a speed not to exceed
30 rpm until the fastening's proof load is achieved. The torquing device
shall not contact the locking device or the threaded portion of the
(6) Each standard and test sample shall be engaged and
disengaged for 15 full cycles.
(b)Acceptable performance. The minimum torque value required to
start removal of the fastening from the installed position (minimum breakway
torque) for any cycle of any test sample shall be greater than or equal to
the average breakway torque of each removal cycle of every standard
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