Turbine wheel salvage

[racket]

Hi Guys

After getting the 12/118 freepower stage finished and cleaning up the workshop I got bored, so decided to see what I could do with the old "dead" C30 4th stage wheel with its broken blading .

Fitted the torque testing shaft in the lathe chuck and fitted the wheel and proceeded to cut through at the break point using the angle grinder , "plunging " in half way through a few blades at a time , then turning the wheel and repeating the process, then reversing the wheel and doing the same again until the outer ring parted .



The result was a pretty raggedly looking set of blades, so with the chuck spinning slowly I used the side grinder to trim the blade lengths to produce an ~170 mm - 6.7" dia turb wheel with blade lengths of ~1.125"







The "new" blades have a more "traditional" look to the tip shape, unlike the flat blade of the full size wheel



Certainly a better freepower shape for stalled use .

The throat area appears to measure ~6,500 sq mms , so say 6,000 sq mms - 9.3 sq ins as effective flow , a bit smaller, ~1 sq in, than the C20 3rd stage wheel ..............its now a potential freepower wheel that could be used at modest rpm as there could be some residual damage to some blades .

I've always wondered if it'd be possible to cut down a 4th stage wheel , now I know it can be done :-)

Cheers
John

[finiteparts]

Very nice John..."When life hands you lemons, make lemonade." - approach to a damaged wheel.

I have a few damaged second stage 250 wheels that I might give a haircut too.

Thanks for posting!

Chris

[racket]

Hi Chris

And a nice drop of "Lemonade" it turned out :-)

The wheel would be suitable for a decent sized DIY engine's freepower of 100 HP , and probably OK for 20,000 rpm

Cheers
John

[Richard OConnell]

Awesome idea John. Be sure to let us know how it turns out!

[smithy1]

John....I may have a couple of time expired C30/C47 3rd & 4th wheels in the next month or so...we've got a couple going through the shop as we speak....if I can get hold of them....would you like them..??

Smithy.

[racket]

Hi Smithy

Yes please :-)

I hope Queensland is treating you well.

Cheers
John

[dieselguy86]

Jan 22, 2020 21:39:25 GMT -5 smithy1 said:

John....I may have a couple of time expired C30/C47 3rd & 4th wheels in the next month or so...we've got a couple going through the shop as we speak....if I can get hold of them....would you like them..??

Smithy.

Smithy, would it be possible to buy a 3rd stage? Ive been watching Ebay but have only been able to find recon'd ones.

[smithy1]

Jan 26, 2020 21:37:43 GMT -5 dieselguy86 said:

Smithy, would it be possible to buy a 3rd stage? Ive been watching Ebay but have only been able to find recon'd ones.

The ones I get probably aren't any better to be honest...they're usually "Time or Cycle Expired" but are fine for our purposes. I don't know what reconditioned really means, they aren't allowed to "re-life" them as they have an absolute life limit.

All going well I should have some in the not too distant future.

Smithy.

[dieselguy86]

Hi Smithy,

John graciously sent me his cut down 4th stage for measuring and build mock up. It fit the bill perfectly for my project. So it looks like I'll be looking for a 4th stager or 2.

Wonder if "reconditioned" means walnut blasted and inspected? Any rate its above what is affordable for this hobby. Id happily pay for shipping plus any extra trouble.

-Joe