Catastrophic Failure Containment Capability of Turbomachinery

[MacMcMacmac]

Good Day,


We are currently doing a detailed HPP (Hazard Prevention Plan) here at our gas turbine research facility we need to know if there is an engineering standard to which turbomachinery is designed so that in the event of a catastrophic failure (i.e. rotor disintegration or blade failure) the casing would contain the debris.

Is there an ANSI standard or is it just good general engineering and design on the part of each manufacturer? We are currently operating 30,000hp worth of compressors, blowers and expanders and we would like to quantify the risk. We also have clients who would like this information to be supplied to them so that they may also update their own HPP protocols.

Thank you.

 

[BigInch]

That's not even a requirement for aircraft turbines.

I hate Windowz 8!!!!

 

[rotw]

Not specialist of the issue... in the meantime here are some thoughts:
Possibly you can have a look at the SIL (Safety Integrity Level) classification used by original equipment manufacturer for their design as an indication of the level of risk involved for a certain category of rotating elements (impellers, couplings etc.). To my knowledge the internals of a centrifugal compressor for example (impellers, rotor) are not a serious risk concern from the stand point of not representing a high probability of projection of rotating parts (missile). A mechanical coupling represents a higher risk of causing injuries/damage in case of failure.
In the technical literature I came across history cases where during catastrophic failure of steam turbines (e.g. one can think about running at no load followed by overspeed scenario) turbine blades have been projected outside the casing...reaching far away location(missile).

I know it exists a (minimum) SIL classification at manufacturer's end that identifies the risk for different categories of rotating parts based on manufacturer risk assessment.

Another thing to possibly investigate is machinery directive or country regulations (such as CE marking in Europe) to see whether it addresses those points.

Also by loss of containment do you mean containment of debris only or also risk of releasing toxic/hazardous substances and possibly occurrence of an explosion ?

 

[iainuts]

We've been doing similar research but I'm not aware of any industry standards. That said, I was searching for the Amde paper we've been researching and saw this just now. Not sure if it's a lead or not:

http://pbadupws.nrc.gov/docs/ML1016/ML101650675.pdf

Regardless, there's a paper by Amde, "Local Damage Assessment of Metal Barriers under Turbine Missile Impacts" that I would highly recommend. The paper claims to be a "... state-of-the-art report on pertinent information [regarding penetration analysis]". This paper reviews 8 different empirical methods and highlights the 3 best. One of these, the Hagg and Sankey method (Hagg and Sankey, "The Containment of Disk Burst Fragments by Cylindrical Shells") is one we've used for a long time but according to Amde, is only accurate for blunt impacts and is rather complicated. Regardless, it also seems to be one of the most thorough.

We've also been studying the BRL method mentioned in the Amde report but haven't gotten a copy of the original paper yet. It's difficult to get hold of, but the Amde paper has sufficient information in it to perform the analysis of all 8 of the studied methods.

If you find anything else pertinant, I'd be interested in hearing about it.

Best regards.

Amde:

http://cedb.asce.org/cgi/

http://WWWdisplay.cgi?97759

Hagg and Sankey:

http://gasturbinespower.asmedigitalcollection.asme.org/article.aspx?articleid=1418505

 

[rotw]

Good point iainuts thanks.

Biginch, about aircraft engines, manufacturers perform an explosion running test of the engine to ensure everything remains within the containment of the engine in case of catastrophic failure, bird strikes, etc.

http://www.youtube.com/watch?v=736O4Hz4Nk4

 

[MacMcMacmac]

Thanks for the suggestions. There are no toxic gases to consider, other than jet exhaust being drawn through the machine. This is strictly a "flying bits" sort of issue. I'm thinking couplings and shafts would pose a bigger risk than the rotors themselves.

Maybe we should just have a blanket ban on anyone entering the compressor rooms while they are in operation. That would make walk-arounds a bit of a problem though.

 

[zeusfaber]

At least one manufacturer works something called a "Group A Components List". These are the items which, if they failed, would not expected to be contained (and therefore cannot be allowed to fail in operation). There's one such list here.

A.