Previous in Forum: Single phase output transformers in parallel   Next in Forum: MPCB for Drive Output Selection
Close
Close
Close
4 comments
Rate Comments: Nested
Associate

Join Date: Nov 2011
Location: mumbai
Posts: 28

Pump Operation

07/28/2012 8:03 AM

dear gurus,

our monoblock does not burn when runs on no load, but submercible pump when runs dry burn out, didnt understand reason?

regards

santosh

Register to Reply
Interested in this topic? By joining CR4 you can "subscribe" to
this discussion and receive notification when new comments are added.

Good Answers:

These comments received enough positive votes to make them "good answers".
2
Guru

Join Date: Oct 2008
Posts: 42355
Good Answers: 1693
#1

Re: pump operation

07/28/2012 10:14 AM

Don't run a submersible pump unless it is covered by water, or fluid. They are not designed to be air cooled.

Register to Reply Good Answer (Score 2)
2
Guru

Join Date: Aug 2007
Location: Earth - I think.
Posts: 2143
Good Answers: 165
#2

Re: pump operation

07/28/2012 10:19 AM

I have no idea what you are calling a "monoblock". Please give a better definition.

As for the submersible pump:

1. A submersible pump will use the fluid being pumped as a cooling medium, to take heat away that the motor is producing.

2. When you run dry, the pump will cavitate. Basically, since it can no longer pump, all of the heat due to friction will be imparted to the fluid remaining in the volute.

3. The above 2 reasons (along with a waste of energy), is why you should have a "low level cutoff" (usually a float switch) in the pump circuit.

__________________
TANSTAAFL (If you don't know what that means, Google it - yourself)
Register to Reply Good Answer (Score 2)
Guru
United States - Member - New Member Engineering Fields - Power Engineering - New Member

Join Date: Sep 2006
Location: California, USA, where the Godless live next door to God.
Posts: 4665
Good Answers: 804
#3

Re: Pump Operation

07/28/2012 12:28 PM

Monoblock fillling machine?

Machines generally don't care if they are loaded or not, but pumps do. A submersible pump should NEVER be run dry. If you need to run the filler/capper in order to set it up or test the timing etc., disable the filling pump first.

__________________
** All I every really wanted to be, was... A LUMBERJACK!.**
Register to Reply
Guru

Join Date: Jun 2010
Location: srilanka
Posts: 2725
Good Answers: 5
#4

Re: Pump Operation

07/28/2012 11:08 PM

When a centrifugal pump runs without water, shaft,seal/gland packing etc will be overheated but motor may not burn out.Give details (type/model/brand etc)of your mono-block pump/deep-well submersible pump/drainage pumps. In deep well submersible pumps bearings and motor are water cooled,if no water they will get overheated. In sewage/drainage submersible pumps motor may be oil cooled so when you run without water what did you observe?.

__________________
pnaban
Register to Reply
Register to Reply 4 comments

Good Answers:

These comments received enough positive votes to make them "good answers".
Copy to Clipboard

Users who posted comments:

JRaef (1); Kilowatt0 (1); lyn (1); pnaban (1)

Previous in Forum: Single phase output transformers in parallel   Next in Forum: MPCB for Drive Output Selection

Advertisement