wholesale square washer,wholesale titanium washer,wholesale toothed Lock Washer

In all kinds of mechanical connectors, bolt locking is a very important link. There are many ways to prevent bolts from loosening in life, including the use of spring washers. Spring washer is often called spring washer in screw industry. So why is it used frequently? It has to be explained from the function and principle of the spring washer.

Function of spring washer:

The basic function of the spring washer is to give a force to the nut after the nut is tightened to increase the friction between the nut and the bolt! This is a protective measure added to prevent the loosening of fastening bolts caused by equipment vibration during operation.

Locking principle of spring washer:

The anti loosening principle of the spring washer is that after the spring washer is flattened, the spring washer will produce a continuous elastic force, so that the threaded connection pair of the nut and the bolt will maintain a friction force and generate a resistance torque, so as to prevent the nut from loosening. At the same time, the sharp corners at the opening of the spring washer are respectively embedded in the surface of the bolt and the connected part, so as to prevent the bolt from rotating relative to the connected part.

However, practice has proved that the spring washer can only provide 10 n/m elastic force, and the 10 n/m elastic force can be ignored for the 280 n/m bolt pre tightening torque. Secondly, such a small force is not enough to make the sharp corner at the notch of the spring washer embedded in the bolt and the surface of the connected part. After disassembly, there is no obvious embedded mark on the surface of the bolt and the connected part. Therefore, the anti loosening effect of spring washer on bolt can be ignored.

From the function and principle of the spring washer, it is not a good method to use the spring washer to prevent looseness, or we should find an ideal method to increase the friction resistance moment.

Locking case of spring washer

The connection between the axle main reducer and the axle housing uses grade 10.9 m16x100 bolts with a tightening torque of 280+20 N.m, which are tightened by a high-precision electric tightening machine. The change of torque with rotation angle during bolt tightening is detected under the conditions of spring washer and no spring washer. Comparing the torque angle curve, it is found that there is always a pre tightening torque of about 10 N.m when there is a spring washer; Without the spring washer, the torque of the bolt is at 0 N.m before the torque rises significantly.

It can be inferred that the spring washer can be completely flattened with about 10 N.m bolt pre tightening torque. Through the inspection with the digital display torque wrench, it is found that the bolt torque has not reached 20 N.m, and the spring washer has been completely flattened, which verifies the correctness of the above inference.

Analysis of the above two points shows that the spring washer can only provide 10 N.m elastic force, and the 10 N.m elastic force can be ignored for the 280 N.m bolt pre tightening torque. Secondly, such a small force is not enough to make the sharp corner at the notch of the spring washer embedded in the bolt and the surface of the connected part. After disassembly, there is no obvious embedded mark on the surface of the bolt and the connected part. Therefore, the anti loosening effect of spring washer on bolt can be ignored.

In addition, a washer is added between the bolt and the connected part. If the washer has quality problems, it is equivalent to adding another potential safety hazard to the bolt connection.

To sum up, when the bolt torque is large (more than 200 N.m), the method of locking the bolt with spring washer will do more harm than good. Therefore, under the action of impact, vibration and variable load, the pre tightening force may disappear at a moment, and the connection may be loosened. On the premise of improving the fatigue strength of bolted connections, one of the measures to reduce fatigue failure is to use thread locking glue to prevent looseness, and apply anti looseness locking glue to the threads. It is a kind of bonding and anti loosening technology to achieve the anti loosening requirements by filling the thread locking adhesive into the clearance of the thread connection pair and bonding (curing) the internal and external threads together.

Searching for a wholesale square washer,wholesale titanium washer,wholesale toothed Lock Washer from China, you can get high-quality products at a nice price.