IEC motor shaft sizes

[geesamand]

Hello,

I work for a machinery OEM. For years we've worked with NEMA motors and managed our production bills of materials based on NEMA frame size. This ensured the keys, couplings, and adapters fit correctly for every machine.

We've recently begun working with IEC motors, mostly D-flange. For frame sizes 225 and up, we're seeing different shaft and keyway dimensions depending on the manufacturer. So we purchased IEC 72-1 (for $340, $5.49 per page written in English) and found nothing to suggest that shaft and keyway dimensions are standardized.

Please tell me there is more to this; that I'm missing something. I'd rather not think about life without standarized motor dimensions.

 

[7anoter4]

I think in Europe are only national standards for induction motor dimensions like DIN. See:
thread404-316919
Mechanical engineering other topics Forum
See also:

http://www.relkocz.com/katalogy/siemens/ca01_2009/eng_132181.pdf

 

[geesamand]

Wow. I wonder if I can return this useless and horrifically expensive chunk of paper. Yes, I'm disappointed.

David

 

[7anoter4]

I understand your disappointment but in Europe one have to calculate the shaft diameter and the shaft key accordingly.
See:

http://www.google.co.il/url?sa=t&rct=j&q=induction motor shaft diameter calculation&source=web

You may use a software as "eassistant" for instance :

http://www.eassistant.eu/en/eassistant.html

http://www.eassistant.eu/fileadmin/...tc/HTMLHandbuch_en/eAssistantHandb_HTML_ench8

 

[ScottyUK]

BS EN 50347 (the English language version of EN 50347) details the standard dimensions, including shaft sizes, for frames in the range 56 to 315. It is probably the document you were looking for originally.

Sorry the help has come after you've spent a lot of money on the IEC document.


----------------------------------

If we learn from our mistakes I'm getting a great education!

 

[MiketheEngineer]

Move to the USA!!

 

[geesamand]

I am in the USA, but supplying internationally now means I must support IEC as well and NEMA.

Scotty, BS EN 50347 sounds like a good option. Especially considering that we are purchasing the motors to the UK and shipping the completed machines from the UK. Do you know if that standard is accepted outside of the UK? For example, would Siemens, ABB, etc follow this standard?

David

 

[ScottyUK]

Hi David,

It's a European Norm, hence the 'EN' designation, so I would expect the major European (IEC) motor manufacturers to conform to that standard. Certainly can't hurt to ask them.


Mike - why would I do that? So many nice places to go instead...


----------------------------------

If we learn from our mistakes I'm getting a great education!

 

[geesamand]

Thoughts like "I would expect" have been disappointly inaccurate so far in this particular exercise, so I will undoubtedly have to look into it.

One question if I may impose even further: the BS/EN standard mentions IEC 60072-1 as a cross-listing. If you have access to this standard, could you please confirm that it declares a single shaft diameter for each IEC frame size? Is it within that "standard", or part of a non-binding annex? I would really rather know with more certainty before I request purchase of another document.

David

 

[7anoter4]

I agree with Scotty since this standard was original German standard:
DIN EN 50347
General purpose three-phase induction motors having
standard dimensions and outputs - Frame numbers 56
to 315 and flange numbers 65 to 740
But, pay attention it is only for GENERAL PURPOSE motors !
There is a DIN standard for cylindrical shaft dimensions :
Cylindrical Shaft Ends; Dimensions, Nominal Transmissible Torques
DIN 748-1

 

[ScottyUK]

EN 50347 is a derived standard, or at least it has borrowed some bits from IEC 60072-1. I haven't got the IEC standard unfortunately, but the EN indicates that for TEFC squirrel cage motors there is a single shaft size for each frame size up to 200L regardless of whether it is 2, 4, 6, or 8 pole. For a 225S or larger frame the 2-pole machines have a smaller shaft than the others.


----------------------------------

If we learn from our mistakes I'm getting a great education!

 

[geesamand]

Thank you Scotty, that seems to agree with what I've seen commercially. Our headaches have been with motors 225S and larger.

We use only 4- 6- or 8- pole motors: does EN 50347 specify a shaft size for frames above 200L in this case?

Thanks again,

David

 

[ScottyUK]

Hi David,

2 pole
250M - 60mm
280S - 65mm
280M - 65mm
315S - 65mm
315M - 65mm

4/6/8-pole
250M - 65mm
280S - 75mm
280M - 75mm
315S - 80mm
315M - 80mm


Hope this helps a bit.


----------------------------------

If we learn from our mistakes I'm getting a great education!

 

[MiketheEngineer]

Been to England - twice. Beautiful place with many nice people and quite excellent fish & chips!!

 

[geesamand]

Wonderful, thank you Scotty. This is a big help and I'm hopeful (again) that requiring the BS / EN 50347 will be the right combination of specificity and commercial availability.

David

 

[ScottyUK]

Mike - it is odd but the best fish & chip shops are frequently in the worst places. Glad you enjoyed your visits - where did you get to?

I've seen a few US airports, but have so far only managed to actually enter the US at Orlando (with work), Vegas (with fiance) and Hawaii (with then-new wife). Liked all of them.

David,

Not a problem, nice to be able to lend a hand. A lot of people here have been unknowingly teaching me for years.


----------------------------------

If we learn from our mistakes I'm getting a great education!

 

[geesamand]

I've done a quick comparison to see who has their shaft sizes following EN / BS 50347:
Baldor = No
ABB = Yes
WEG = Yes
Siemens = Yes In fact they mention EN 50347.

This was limited to 4/6/8 pole, AC, general purpose motors ranging from IEC 250M to 315M. YMMV.

David