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Principle of din25201 double fold self-locking washer
The inclination angle α of the inner helical tooth surface of the unique washer is greater than that of the bolt thread. The friction coefficient of the radial convex surface (outer knurled tooth surface) on the outer side of the washer is larger than that of the inner helical tooth surface, and it is occluded with the contact surfaces at both ends. When the connector is vibrated and the bolt tends to be loose, only the relative lifting and staggering between the inner helical teeth of the two washers are allowed to generate lifting tension. The unique tooth system uses tension to produce a high resistance at the tight joint to withstand the vibration force, so as to achieve 100% anti loosing effect.