Noise in Pump

[garciaf]

here´s my issued:
I have a single stage centrifugal pump (Sulzer, ZE80-2250), this pump deliver premium gasoline to the loading rack. The first problem was doing a change of thermic oil for the API PLAN 52 (unpressurized seal, double mechanical seal H75VK), we detect the presence of gasoline, the thermic oil practically has dissapear from the reseivior (API PLAN 52), so due to this, I decide to change the double mechanical seal, I notice many scratches (see image attached) it seem that the shaft was bent. the innusual it is that the pump was working good, until we detect the leakeage. when we install it and rotate manual (primed the pump) and later with the electric motor. The next day present a noise even overheating in the casing pump, so we decided remove it again, we check everything and all is Ok, in the mounting, we disconnect the sucction line and installed again and the noise persist, and even when we put gasoline the noise was more significant. Please help.
Also another datail is the presence of solids (corrosive material from piping).

 

[Artisi]

Has the shaft been checked for straightness?
impeller bore / shaft. Is there some problem with the fit?
Is the pump motor alignment correct?
Is there any pipe loads being applied to the casing (distorted case)?


It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)

 

[Strong]

Did you conduct vibration analysis to check condition of shaft bearings?

Walt

 

[garciaf]

We checked the runout and gave us 1.5 mils, that is Ok.
the clearance between wear rings is 15 mils.