Agitator Nozzle Flange Face Roughness Requirements

[nur12]

Hello,

We are planning to install an agitator in the bottom head of the vessel. My question: are there any specific requirements to the roughness (AARH) of the face of the flange connected to the mounting flange of the agitator?

 

[unclesyd]

You should go with what finish that is recommended by the gasket supplier/manufacturer.

 

[Jalink]

nur12,

However the answer from unclesyd is a very accurate answer to your question, I would like to draw you attention to another very important point to achieve a tight connection, being the bolt closing torques.

If the agitator is hanging on the nozzle and/or causes substantial dynamical loads, the bolts should be prestressed sufficiently leaving the sealing member (gasket) acting as a spring.