Reasons and solutions of stainless steel screw and nut locking

When we use stainless steel screws, nuts and bolts, we often encounter the problem of locking, so what is the cause? How to solve this problem? The deflection Angle of thread matching and the soft characteristic of stainless steel are easy to cause the matching of locking screw and nut.

With their respective implementation of the international standard tolerance range, so the internal and external threads in conjunction with the central axis is basically not the same line, because of the tilt and reduce the internal and external thread contact surface. Uneven or slanting force during locking.

Cause the maximum tilt of the central axis of the screw and nut, so that the surface of the screw and nut thread does not fully contact, by the surface force to point force or force on each unit becomes larger. Generally, the larger the deflection Angle is, the smaller the force area of the thread fit is, and the more easily the tooth lines are damaged.

Stainless steel is relatively soft to carbon steel, if the locking process friction dropped iron filings, will adhere and do not fall, thus interfering with the smooth thread in and out, resulting in tooth bottom and tooth top. When locking the nut, the torque (locking force) must be greater than the friction of the screw and nut itself before the nut can be turned.