4 replies to this topic

[omnibus]

In one of the HAZOPs we were considering the consequence of cavitation and dry running of a barrel type multistage sealless pump. The consequnence was decided as pump damage but no loss of containment becasue the vendor says that this type of pump cannot leak even if damaged due to cavitation or running dry. Is he correct?

Edited by omnibus, 29 April 2014 - 10:27 AM.

[omnibus]

waiting for an answer .

[fallah]

omnibus,

 

Appears vendor is right and due to sealless characteristic there would be no seal leak and subsequent loss of containment, but final judgement should be performed by vendor document in-depth review...

 

Indeed, if there would be adequate safeguard for the relevant consequences (here it might the deviation be low liquid level in suction drum) by which the pump would be tripped, let say, through an interlock you might have no concern for the consequences of pump's dry running...

[omnibus]

Thank you Fallah for the info..

My concern was only to find out if the damage to pump due to running dry can lead to LOC or not. Ofcourse there are safeguards but first consequences need to be established.

So it is possible that in some designs damage due to dry running of pump may not lead to LOC.

[fallah]

 

So it is possible that in some designs damage due to dry running of pump may not lead to LOC.

 

omnibus,

 

In fact, in such sealless pumps, the pump bearings and the shaft that will support them are located inside the casing so the potential of LOC in the event of a bearing failure due to dry running might rarely be happened...