Impeller API610 pump

[adula29]

Is it a possible to use in api 610 pumps impellers witch are made by welding.
Firstable machined semi open impeller and then welded front shroud.

 

[Artisi]

Yes you can, but why - it's not worth the time or trouble.

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.)

 

[TugboatEng]

What is the cost of failure?

 

[Artisi]

TugboatEng:
I know of 4 mid / northern European companies that fabricate stainless steel impellers plus I was involved it the manufacture of steel open impellers for heavy duty contractors pumps (prompted by long delivery of supply from parent company) in one of my previous lives.

no failures - but engineering has to be correct.

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.)

 

[TugboatEng]

Oh I'm not implying a fabricated impeller would be prone to failure. Welding a shroud on to an open impeller is certainly possible, I have done it for a prototype (it only had to prove the pump curve but it worked). I'm just saying go ahead and do it provided a shutdown of the pump doesn't carry any risk whether to safety or revenue.

 

[adula29]

Artisi:
Why? maybe because the workmanship and surface roughness of the machined impellers is better than cast
I'm afraid that welding of narrow channels and vanes curvature may be difficult.
Will welding not cause deformation of impeller?

 

[Artisi]

Surface finish depends on casting techniques and materials.
What size pump/s are you discussing?

I would suggest you look for a high quality foundry experienced with impeller castings and discuss your proposal along with a metallurgist with good foundry experience.

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.)

 

[EdStainless]

We used to do this all of the time. We had slots in the shroud to weld through.
Though in our case the open impeller (bottom and vanes) were a casting.
I am not very fond of the ones with the vanes welded at top and bottom.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy

 

[adula29]

I have Impeller specific speed nsq ~21 (SI units).
b2=20mm (impeller outside width)
d0=170mm (impeller eye diameter)
d2=330mm (outside diameter)
7 - vanes

 

[Artisi]

Buy from the manufacturer.

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.)

 

[LittleInch]

Is it possible - Yes (but you will need some very good drawings and manufacturing skills)

Is it a good idea - No



Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[adula29]

I'm a producer, or rather I work for him ;-)
The problem is that the customer would like such a welded impeller, suggesting that the accuracy of workmanship is better

 

[TugboatEng]

I don't think accuracy and workmanship are terms normally used to rate the performance of an impeller.

 

[Artisi]

Pirating pumps/parts for me is against my principles, therefore end of discussion on my part.

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.)

 

[adula29]

Artisi...
It is not piracy. We are looking better, faster method to produce impellers with this same recurrences.
Of for example pump has ten impellers and casts are with some difference.

 

[Artisi]

Are talking about parts from the manufacturing company being low quality?

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.)