When installing a flat washer with a nut, everyone will more or less encounter the problem of front and back installation: smooth surface and rough surface (relative), which side should be close to the part for better effect, and what is the big difference?

To solve one of the problems first, use the flat pad on the front and back.
We know that the flat washer is mainly stamped out of an iron plate. The shape is generally a flat washer with a hole in the middle. With the spring washer, it is installed in the order of one spring washer and one flat washer, that is, the flat washer is next to the surface of the machine, and the spring washer is on the surface of the machine. between the flat washer and the nut.


There are two functions, one is to increase the contact area between the screw and the machine; the other is to eliminate the damage of the spring washer to the surface of the machine when the screw is removed.
It can be seen that how to use the front and back mainly depends on what role the flat pad needs to achieve.
If it is only used to reduce looseness, then you can choose to place the non-smooth surface close to the part. But if you want to better protect the part, it is better to choose the smooth surface close to the surface of the part.


You may also want to ask, if both are implemented, or which one is the least risky to use?
This involves the second question: what is the big difference between the positive and negative use?
The calculation formula in the “Quality Encyclopedia of Standard Fasteners” published by China Standard Press is: 1000-piece weight m=0.00785×{3.1416/4×washer height×[square of outer circle diameter-square of inner hole diameter]}. However, due to the different standards of various countries and the error of the information, here is a temporary US flat pad standard for everyone.

That is to say, when making flat pads, it is possible to achieve a surface treatment that is as smooth as possible on both sides.
In this way, we can make requests when customizing or purchasing flat pads from the factory. For example, if the smooth surface is required to be close to the surface of the part in industrial production, but at the same time, the wear of the part is required to be reduced, the standard can be required, and of course, the purchase price must be increased accordingly.
In fact, in the general daily situation, the probability of loosening is much less than the frequent damage to the surface of the parts due to the connection.
It’s like most people will tell you that it’s possible to have the rough side away from the nut and the smooth side closer to the surface of the part.

In addition to the above metal flat gaskets, non-metallic flexible gaskets in processing and production are also very common. For example, rubber gaskets, graphite gaskets, asbestos gaskets, non-asbestos gaskets, silicone gaskets, etc.
The sealing accuracy of these gaskets also requires important attention. The premise of these realizations is the accuracy of the cutting gasket.
Take flange gaskets as an example.


The flange seal mainly relies on the pre-tightening force of the connecting bolts and achieves a sufficient sealing specific pressure through the gasket to prevent the leakage of the sealed pressure fluid medium. There are many reasons for its leakage. The compression force of the gasket is insufficient, the roughness of the joint surface does not meet the requirements, gasket deformation and mechanical vibration, etc. will cause the gasket and the flange joint surface to not tightly seal and leak.
So how can we increase the sealing performance of the gasket and improve the efficient and high-quality processing of the gasket factory?

Choose Longtaidi, we could supply you with satisfied flange and gasket.

We have seen too many big problems caused by small spacers. In the future, we hope that there will be no more misfortunes caused by the slightest.

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