Big Frick was locked up

[bruceboldy]

Hi

I have a question. We obtained a new/damaged Frick 88something bare screw that was locked up tight
After disassembly we found that it had water in the disc end rusting the inside and reducing the last 2 inches of rotor lip seals to nearly nothing.
From my old days I know could rework that lip seals, but what happens if we just clean it up and not repair that last section of rotor. The housing has some pitting, but can we just hone it down and expect ok operation

Your comments and suggestions are appreciated.

Oh yes I was with frick years ago been with Trane a few yrs and now with GEA and their Polacel cooling towers Need a tower let me know...

I wil attach a pic when i get it to load..

Bruce

[CanadianIce]

I've reassembled machines that had the lip seals ground off and only had minimal capacity loss. New Mycom screws don't have lip seals on the edge of the rotor. I would just take the roughness off the housing but wouldn't try to remove the pits completely if it meant removing too much metal. I'd be more concerned about the surfaces in the clearance space between rotor and outlet housing.

[Magoo]

Lip seal clearances give compressor efficiency, loose that clearance will reduce flow rate and create high by-pass and high oil/discharge temps., pitting in barrel will add to in-efficiency. best advise is scrap it. You could increase oil flow rate to compensate, but will be really growly.
The last time I looked Mycoms had the same rotor lip seals.
magoo

[RANGER1]

Pictures will help , but i'd agree with
CanadianIce .
I have pulled plenty apart with major damage and no one new about problem until then .
Its sometimes up to someones budget as well .

[nh3wizard]

I would like to see some pictures...

[bruceboldy]

Here are two pics I have Hope you can see them ok

[RANGER1]

Bruceboldy ,
Its a lot different than you originally described as its had a meltdown .
You still could overhaul it if you were desperate also depending on rotor casing damage we havn't seen . But it wouln't be worth the trouble or expense .

Get a new one

[IceMan_4000]

Bruceboldy ,
Its a lot different than you originally described as its had a meltdown .
You still could overhaul it if you were desperate also depending on rotor casing damage we havn't seen . But it wouln't be worth the trouble or expense .

Get a new one

I agree Ranger, Unless you think pouring horse power into a screw for diminishing returns is a good idea. You are going to lose capacity in that machine

[The Screwdoctor]

He Bruceboldy,

all depends on what your customer wants. If they don't care and just want something that does 80% of what it supposed to do then after some grinding and polishing you could create a compressor that will work, but if you want to perform a refrigeration engineer worthy overhaul this rotorpair is finished. Indeed it looks like the rotors have seized quite a bit. You want to give your customer some guarantee that the compressor will operate the full 40 or 50.000 hrs. that it normally should do. If you are going to overhaul the compressor with these rotors at least have it checked for unbalance or else all your effort is for nothing when the compressor is started up and somebody wants to do a vibration analyses on the compressor.

The Screwdoctor