Corrosion in 316 under cavitation 1

[aatara]

Hello, I have a 316 SS 30" (Schedule XS) pipe after a multiorifice plate in a water cooling systems of a power plant. I have signs of cavitations (sounds). I´d like know the problems associated and the erosion-corrosion rate.

Should I test the pipe unde UT to determine the evolution of the wall thickness?

Thanks in advance

 

[smp263899]

Hello,

I would like to know wether you notice any vibrations,
this problem can be solved by Ultra sonic testing.

Regards

SM Patil

 

[hacksaw]

The cavitation damage down stream of orifice restrictions is usually confined to intrusive fittings and other inline equipment (valves, elbows, etc.) immediately downstream.

The pipe wall does not seem to be seriously affected in my own experience.

There are always exceptions. If you have an opportunity to inspect, take advantage of it, but it is not a critical issue.

 

[aatara]

Thank you for your answer,

smp263899: I don´t have excessive vibration, only the characteristic sound of the cavitation (litle stones transport by the flow), after inmediately of the plate (RO).


hacksaw: Do you think the 316 SS is a good material to prevent this problem?

 

[hacksaw]

usually the cavitation damage is down stream. 316 should be fine.

It does not hurt to check the plate during scheduled down time, if you are concerned. If damage is nil, then you've answered the concern.

 

[25362]

Cavitation produced by ultrasonic waves is sometimes used to clean metal surfaces, to destroy liquid-borne organisms, to disperse liquid-born particles, and to produce colloidal suspensions and emulsions.

I've witnessed ultrasound "cavitation" applied in-line to collapse and crumble wax crystals in solvent dewaxing of lubes. I've also heard of ideas on using this procedure to treat waxy crudes to avoid wax deposition in piping and storage.

It appears that "dreadful" cavitation has its own practical and beneficial uses.