[THE FACT ONE]
"MUSCLE NUT" WILL NOT FALL OFF

JQA
Jan. 2011
  • * In Vibration Endurance Test (NAS3350) performed by JQA-Japan Quality Assurance Organization, our Muscle Nuts in all sizes did not loosen for 17 minutes.
  • * In cases they loosen, they will NOT fall off.
  • * The secret of the mechanism is in the spring coil.
  • * When tightening the nut, inside the coil spring it expands and tightens the nut.
  • * It is possible to increase the tightness.
  • * When the nut is being loosened, the spring coil twines around the bolt neck, and stops the nut from getting loose.
  • * This is the Fall-Off-Prevention Mechanism.
  • * The strength of twining of the spring coil is adjustable.

JQA 2
Jan. 2011

Testing Method

A test piece is set to a tester; the test was performed under the following condition to measure the loosening torque for 17 minutes during the time the nut did not get loosen.

  • Tester: Captive Screw Slack Tester
  • Condition of Vibration: Vibrating @ 1,780 rpm
  • Vibrator Base Stroke: 11 mm
  • Impact Stroke: 19 mm
  • Direction of Vibration: Perpendicular to the bolt axis

Assessment Method of Slackness Test: The definition of "loosened" is when the marked points of testing bolt, nut and washer become out of alignment, and the washer could be turned manually. The loosening torque is measured at the completion of the test with duration of 17 minutes.

Note:
1. Tightening Torque level was set by the instruction of the test requester
2. The materials (Bolt, Nut, and Washer) were provided by the test requester.


Locknut(Muscle Nut)+Disc Spring Washer:
Did Not Loosen for 17 Min.

Muscle Nut 2

NEXT: THE FACT 2

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