1, the difference of locking function:

Spring washers have a relaxing effect, while flat washers do not.

2. Different roles:

The function of flat gasket is to increase the fastening contact area, and the function of spring gasket is to be used in places with vibration to prevent looseness.

3. Different places of use:

Due to the material and process limitations of bolts and other fasteners, the bearing surface is not large, so it is necessary to reduce the compressive stress of the bearing surface to protect the surface of the connected piece. At this time, a flat pad must be used.

If there is no spring washer on the bolt connecting the motor with the frame, the vibration of the motor will loosen the nut, so it is necessary to install the spring washer on the fastener with vibration equipment.

Extended data

Causes of ring-opening expansion and hydrogen embrittlement fracture;

1, the swelling of the spring washer is generally not the problem of the spring washer itself;

2. The spring washer with expansion ring must bear a radial external tension, which comes from the tightening axial force generated by tightening torque;

3. The outer chamfer of the nut bearing surface makes the axial clamping force produce a radial component, which makes the opening of the spring washer expand. The smaller the chamfer diameter, the greater the possibility of bulging;

4. Adding a flat washer between the nut and the spring washer is helpful to slow down or prevent the occurrence of ring expansion, but the flat washer is too thin or too soft to prevent ring expansion;

5. The reason of hydrogen embrittlement fracture of spring washer is generally that the heat treatment process is unreasonable, and it is not dehydrogenated in time after galvanization, which leads to fracture;

A large number of experiments and long-term practical experience have confirmed the above analysis.

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