wear ring- corrosion

[apadana]

Dear All,
We are going to prepare a Material Requisition for a centrifugal pump for concentrated Sulfuric acid, (>98%) unloading application. Per API 610 standard we had specified Class S-1 material. The client has called for stainless steel (304) for case and impeller wear rings. I am wondering if there is any risk of galvanic corrosion between the wear rings and the impeller or case ?
Thanks,

 

[EdStainless]

please don't post the same question in multiple forums.

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P.E. Metallurgy, Plymouth Tube

 

[pumpking]

Two questions here:

1) Why do you need API specification for such an application, our standard PFA lined pumps do this type of application every day and question the need for API ratings ?

2) Question the material you are considering here also - if you drop the concentration down by only a couple of percent then you will get quite severe corrosion. Tanker unloading facilities tend to get frequent 'wash down' due to potential splashes and the general environment so can quite easily be a real problem to consider.

Have a look at our ETN or UTN-BL series of PFA lined magnetic drive pumps as a real solution to your duty.

Ash Fenn

http://www.cdrpumps.co.uk