Hi Forum members, We experienced a 2

[Guardiano]

Hi Forum members,
We experienced a stainless steel basket failure on one of our sugar centrifugal machine. The basket spins at a maximum speed of 1100 RPM. I am attaching a picture of the tear. Any reason for the root cause ?
Thank you.
Guardiano

 

[TugboatEng]

This is a good picture of the failure but it shows us nothing of the system.

 

[EdStainless]

And we need to know what alloy it is.
A wider angle photo showing the entire part would help also.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, consulting work welcomed

 

[btrueblood]

Is there supposed to be a slit/cut between the top sets of holes? If that is a crack, it's suspiciously straight...

 

[mfgenggear]

was there any non destructive test during forming or manufacturing (eg heat treat, welding). verifying there was no indications before hand. look at manufacturing sequence and verify this.
from there as others said not enough information. start with the manufacturer. make a fish chart of possibilities of the failure. list any possible causes then eliminate them.
contact a metallurgical lab and discuss what they need for failure analysis.

 

[IRstuff]

Does the basket have a brazed joint at the break?

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert!

https://www.youtube.com/watch?v=BKorP55Aqvg

faq731-376 forum1529 Entire Forum list

http://www.eng-tips.com/forumlist.cfm

 

Attempting failure analysis by crowdsourcing based on a few pictures, you will get exactly what you pay for.
Retain a metallurgical laboratory or competent professional engineer.

"Everyone is entitled to their own opinions, but they are not entitled to their own facts."

 

[dik]

'fish chart'??? I've never seen a tear that pristine... any sort of seam underlying? Can you take a sample and review it microscopically? I don't know what facilities you have.

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik

 

[DAVIDSTECKER]

From a manufacturing point of view, I'd venture to guess that the basket was roll formed and seam welded.
A failed weld might explain how straight the break is.
Then maybe add the misfortune of drilling holes right in the seam?
If you do take some more photos, see if you can get a view of the crack walls.

 

'fish chart' is indeed a thing.
As far as I have seen it is only practiced by MBAs in suits who have never pounded a shop floor for the manufacturers who remunerate them magnificently.

"Everyone is entitled to their own opinions, but they are not entitled to their own facts."

 

[dik]

I still don't know what a fish chart is... never heard the term...

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik

 

Then don't ask! You haven't missed anything.

"Everyone is entitled to their own opinions, but they are not entitled to their own facts."

 

[dik]

curious mimes want to know...

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik

 

[mfgenggear]

dik (Structural)8 Apr 21 16:25
I still don't know what a fish chart is... never heard the term...
Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

here is the info if interested, for me with 45 years of experience it helps me focus on root cause.

https://en.wikipedia.org/wiki/Ishik...zed in,founding fathers of modern management.

 

[dik]

Thanks... I checked google for fish charts and ended up with 'fish'... nothing relevant...

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik

 

[EdStainless]

Commonly referred to as 'fish bone chart'

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, consulting work welcomed

 

[dik]

Thanks, Ed... I'd never heard of either... my sheltered existance, I guess.

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik

 

[mfgenggear]

dik (Structural)8 Apr 21 17:29
Thanks... I checked google for fish charts and ended up with 'fish'... nothing relevant...

yes sorry and thanks ED for clarifying.
My brain has senior moments at times yes Fish Bone Chart

 

[EdStainless]

No Dik, you are just luck to have not been drawn into the whole QA/problem solving/root cause nightmare.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, consulting work welcomed

 

[weldstan]

Without a clear picture of the entire fracture and the fracture surface, it's impossible to determine fracture initiation site and cause, in addition to the comments of others herein.