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How does the sealing manhole cover achieve the sealing effect?

Jun 15,2023


Sealed manhole covers are usually sealed in the following ways:

1. Sealing material: Add sealing materials, such as rubber, polyurethane, silicone, etc. around the manhole cover and fill it between the manhole cover and the wellhead to form a sealing layer to prevent sewage, sediment, rainwater, etc. from infiltrating into the well.

2. Elastic seal: An elastic gasket, such as a rubber gasket, is arranged between the manhole cover and the wellhead. When the manhole cover is closed, the gasket can automatically rebound and fit tightly to the wellhead to play a sealing role.

3. Threaded connection: Threaded connection is used between the manhole cover and the wellhead, which can be tightly fitted after tightening to form a sealing effect.

4. Gravity sealing: A gravity sealing structure is set between the manhole cover and the wellhead, such as a trough-shaped manhole cover and the wellhead. When the manhole cover is pressed down, it can be automatically embedded in the groove to form a sealing effect.

In summary, there are various ways to achieve the sealing effect of the sealing manhole cover, which need to be selected according to the specific situation.

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