6 replies to this topic

[Rahimzadeh]

Dears:

 

Please tell me what causes propane transfer pump casiing frosted?

 

what is prevent measure for frosting?

 

best for all you

[thorium90]

Frosting? As in ice? Seems normal. At certain pressures and temperatures, it is a cold liquid...

Edited by thorium90, 23 February 2013 - 10:30 AM.

[TS1979]

If the propane temperature is below 0^oC, frosting in the pump case may be normal when the pump environment has a high humidity. To prevent the frosting, you need to insulate the pump.

 

If the propane temperature is above 0^oC, the frosting on the pump casing indicates that you have propane flashing inside the casing which may also result in the pump cavitation. You need to check if you have enough NPSH available for the propane transfer pump.

 

Thanks.

[Raj Mehta]

TS 1979,

 

Can you elaborate a bit, I am unable to understand the concept. When the temperature is below 0 deg C, then at what pressure will the frosting be natural within the pump ? How will the pump environment have high humidity ??

 

Insulation & a light color (heat reflective) paint would not allow the heat to be absorbed and thus it would sustain in hot & humid conditions without the frost on the outside of the pump. How will the frost form inside the pump, I am unable to get that sir. Kindly explain me  

[thorium90]

So does you pump ice something like that?

 

(Found these off the net)

 

http://www.flickr.co...832655/sizes/l/

 

http://www.flickr.co...629349/sizes/l/

 

 

[neel_avi]

Dear Mr. rahimzadeh,

 

Since you have mentioned only about frosting I assume the following:

 

1. Pump/s is/are in continuous operation.

2. No other abnormality on pump side is observed when its running.

3. The pump has been designed suitably for the ambient conditions and process conditions are normal (level in the vessel, suction and discharge pressure of the pump) that it is now at.

 

I would sugest you to check for passing valves on casing vents or seal vents if they have not been checked yet. 

 

Your post leads me to think in that line solely - simple though. 

 

Hope this helps

 

regards

 

Avijit

[TS1979]

Mehta26,

 

My understanding is that he is talking about the pump casing outside. If you said it was inside the pump, my question is how do you know the frosting inside the pump? Can you see the frosting or the ice building up?

 

Thanks