Spring washers are used to prevent loosening of nuts under the nuts and are described in national standards. Hexagon slotted nuts are designed to be used with bolts at the end of a screw to insert the cotter pin into the hole of the screw from the groove of the nut to prevent the nut from loosening automatically. It is mainly used for occasions with vibration load or alternating load .
In the mechanical design, production to prevent the nut (or bolt) automatically back loose methods are:
1. Gasket spring washer; (easy to do)
2. With hexagonal slotted nut + cotter pin; (an increase of processing)
3. Padded washer washers (an increase of processing)
4. Hex head bolt hexagon head hole Insert steel wire. (An increase of processing operations)