Under what circumstances does a Rubber Expansion Joint need to be equipped with a negative pressure ring?

The installation of a negative pressure ring on a Rubber Flexible Joint is typically required in pipeline systems where negative pressure conditions may occur. Negative pressure refers to a state where the internal air pressure within the pipeline drops sharply due to certain factors, creating a suction effect. If the Rubber Soft Joint cannot withstand such negative pressure, it may collapse or get distorted, thereby disrupting the normal operation of the pipeline. Specifically, here are some application scenarios where a negative pressure ring may be necessary for Rubber Expansion Joints:

1.Vacuum Pipeline Systems: In these systems, the internal pressure within the pipelines is lower than atmospheric pressure.

2.Inlet and Outlet of Water Pumps: Especially during pump startup or shutdown, temporary negative pressure zones may form.

3.Certain Industrial Processes: Such as gas exhaustion or suction operations, which can lead to a decrease in internal pipeline pressure.

The function of the negative pressure ring is to protect the rubber bellows (ball body) from collapsing under negative pressure conditions, thus ensuring the normal operation of the pipeline and enhancing the applicability and safety factor of the Rubber Joint. When installing the negative pressure ring, it is crucial to select an appropriate material and ensure proper installation to provide additional protection in corrosive pipeline environments.