Uneven Radial Clearance of Labyrinth Seals

Anywhere from absolutely nothing to catastrophic failure.

Your question is akin to "what happens when I hold my breath?"

With luck, extra clearance in one passage may be compensated by reduced clearance in an adjacent passage.

You do not believe in Murphy's law ?

I'm not sure the experiment will work. I don't remember if I voted the GA in the first place, but if I did, then voting OT now would undo my own previous vote. If somebody else voted the GA, then my new vote wouldn't undo it. In any event, I will oblige the request. If someone else weighs in in the meantime, all will be murky.

Further report: the original GA was someone else's. My new OT made the score 1-1.

I don't believe that you would have voted such an answer as good.

Anyway, I negated your GA vote, as you can see.

I'll try to reverse it in a minute.

I don't see how you can negate my GA vote, since I wasn't the one who gave it. If you now vote your own answer as OT, it will show 5 OT votes net (1-6).

That's my point.

Anyone can erase anyone else's GA vote by simply voting it OT, as I did you and you did me.

That's not what happened.

I just voted your #6 OT.

Let's see what that does.

< Edit. The GA that was there disappeared.>

We'll see if it reappears.

Irrelevant. The vote score is 1-1. Nothing was removed, just a weight added to the other pan of the scales.

Apologies to Arshad for these digressions. Ordinarily they should have been self-voted OT, but that would have upset an experiment.

Right, our my experiment has distracted the discussion.

Apart from dropping the efficiency the Rotor may be bounced resulting in subsynchronous rotor vibrations, rubs, localized heating.......

As long as they are within the norm given by OEM, it is OK.

The information provided by you is highly insufficient. The desirable information for such questions may be:

- Number of stages

- Gas handled

- Shaft labyrinths or impeller labyrinths

- Is it stage to stage variation or different clearance at different points in same stage

- Suction and discharge pressure

- Seal gas used and its pressure

Dear.

No of stages 8, both shaft and impeller labyrinth, synthesis NH3 gas, suction pressure 900# dis pressure 2100# balance piston seal is labyrinth seal and floating bushing seal is used to seal the gas.

There should be labyrinth seals or honeycombs like sealing arrangement around 'balance piston/drum' as well. The mechanism that enlarged the labyrinths at inter stage spacing could enlarge the balance piston sealing clearance also. This more dangerous, besides the huge bypass, could affect the axial balance as well. If abnormal, should express by increasing thrust bearing temperature. Well, as mentioned by pritam, as long things are within the range, well and good, keep watching.

Leaks, vibration(s), frustration, added maintenance, higher cost(s), angry customers/employees.