impeller diameter range.
impeller diameter range.
(OP)
hii guys,
how to find out the max and min impeller that can be used of a specific pump body. and hw is it different from size tolerance of impeller?
If somebody can put some light into this, please help me out.
how to find out the max and min impeller that can be used of a specific pump body. and hw is it different from size tolerance of impeller?
If somebody can put some light into this, please help me out.





RE: impeller diameter range.
smart in this forum - but fortune telling isn't one of outlet strengths.
The best way to find the answer/s is to contact the pump manufacturer or agent with the following, pump brand, model, driver size and speed, duty required and a reason for change.
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.)
RE: impeller diameter range.
Difference? Think about a bit more.
tolereance is a +/- dimension acceptable from a given figure
Max and Min are the limits of the size.
E.g. impellor size varies from 110 to 160mm. Tolerance is +/- 3mm from any stated size given by the specific pump data sheet, e.g. 145mm
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
RE: impeller diameter range.
RE: impeller diameter range.
RE: impeller diameter range.
I am tryin to get an ul (underwriters labourtires)approval for the pumps which are manufactured in a chinese company.
For expample. One of the pump is 100 gpm at 9 bar.
At first the chinese company gave me a data sheet which shows maximum impeller dia as 342/min as 309 and rated dia 315.
Then i told them at the time of testing instead of testing with the rated impeller we wil test with the max and min impellers so that we get a range of models approved.
When i told this they told me the values they gave for max and min was size tolerance and they gave me new values as max 315 / min 270 .
the logic behind this i couldnt understand.. the tolarence values are more than max and min ?
These questions might find easy for you guys. But i am relatively new to design part and the chinese company i deal with is a big and well established one in pump manufacturing. So when they say it so strongly i thought i should go for expert advice and i am here
RE: impeller diameter range.
Sounds to me like you've suddenly been given the next impellor range down (270 to 315). However, if the max impellor tolerance range was 322, then the range 270 to 315 is prob OK and while you wouldn't normally aim for a rated diameter at 100% of range, for a simple pump like this it doesn't really matter.
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
RE: impeller diameter range.
Initially, I would ask them for a standard set of curves for the impeller diameter range for the pump and also ask if there are other impeller configurations (design) that can be fitted in the pump.
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.)
RE: impeller diameter range.
RE: impeller diameter range.
In this way they can cover a range of performance. Larger/thinner impellers give more head and less flow, but if done correctly the HP will be similar for the smaller/thicker high flow lower head option.
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P.E. Metallurgy, Plymouth Tube
RE: impeller diameter range.
This is fire pump.
Actually we are a manufacturing company in uae. we manufacture most of the fire fighting equipment here. Now we need a ul approved pump in our name.
So we tied up with this Chinese company agreed we will give good orders if we UL approval for their pumps in our name
So if the impeller dia vary inside the tolerance range the output of the pump should not change right? but if the impeller dia varies btw max and min the power, head , discharge everything changes.
So tolerance can never be a bigger range than the max and min impeller.
dealing with Chinese manufacturer is a really hectic task, Due to communication problem. But to get cheaper products one other way.
RE: impeller diameter range.
Complying with FM /UL is a long involved and exacting procedure with tightly controlled specifications and approval including testing.
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.)
RE: impeller diameter range.
With a reputable pump manufacturer and modern production methods, the impellers will have uniform dimensions over the production run. Each pump manufacturer makes several different sizes of impellers for a specific size of pump. Each impeller will have a unique performance curve associated with the size of pump and the size of impeller.
Ask the manufacturer for a set of pump performance curves for each pump that you desire to have UL listing.
As Artisi posted, obtaining UL listing for a pump will be a comprehensive endeavor and an expensive investment on your end.
RE: impeller diameter range.
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.)
RE: impeller diameter range.
I have to place order now. But to do that i am confused. When they told about two types of max. and min. impeller diameters.no clue for which i will place an order so that while testing i will get a range of models approved. with different gpm and head.
I am really thankful for all your support for taking your time to help a rookie like me.
RE: impeller diameter range.
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.)
RE: impeller diameter range.
RE: impeller diameter range.
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.)
RE: impeller diameter range.
Thanks for your support i admire the depth of knowledge you have. I really want to be like that. IF there is any good book or reference you can give me to acquire a deeper knowledge about pumps i would really appreciate it.
RE: impeller diameter range.
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.)
RE: impeller diameter range.
Agree with Artisi and bimr.
Each kind of pump has standard performance curve with standard impeller diameter.And also has others non standard curves with non standard impellers(e.g.open,semi-open,closed,different diameter/flow channel).Forget your Max/Min diameter things,choose the standard impeller for each size pump.And you could find tolerance of the impeller as per established standard.
Heavy-Duty Centrifugal Slurry Pump Manufacturer
www.gempump.com
RE: impeller diameter range.
Ul pumps can only have closed impellers. So if i go for the tolernce will i get a range of pumps ? Becauase tolerance of impeller will give the same output as the rated one right? I need to get a range of pump outputs
RE: impeller diameter range.
Why do you keep fixating on "tolerance" ? +/- 1mm dimension is ok for your impeller tolerance.
You need a range of pump outputs ? Just test the standard impeller with changed flow rate/head/speed/NPSH.Then you will get the curve you need.
RE: impeller diameter range.
RE: impeller diameter range.
RE: impeller diameter range.
thank you guys for your help... just came here to inform that my work has been approved and i am going to china on 5th for the pump testing.
RE: impeller diameter range.
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.)