Bitzer csh9573-180 screw demister pipes broken

[RACREF]

Good day everyone

I have been rebuilding piston and screw compressor for many years.
At the moment I am busy with 4x Bitzer CSH9573-180 screw compressors for 1 client.
All these compressors run on R134A water cooled chillers

When I opened the compressors all the parts, casing and components looked immaculate except for a broken demister pipe.
I found 2 of these compressors (from different sites) have the same problem. The demister (Built-in oil separator) discharge pipe has broken.
I have attached pictures (Below)

Has anyone else experienced this or have any ideas as to the cause?
Keep in mind that all other components are in very good condition and this is the first time the compressors have been opened.

regards
Andrew


BITZER CSH95 BROKEN DEMISTER PIPE.1.jpg
Broken demister pipe.3.jpg

[seanf]

Have a careful look at the crack surfaces, it might show how it failed.
Could it be a defect in the material at the weld point has grown into a crack by fatigue?
Could temperature changes or vibration be cyclically stressing an area?

[mbc]

Hi

I think it comes from temperature changes.

it is in discharge side and it is hot about 80 C

If system has liquid back from Evaporators in large amount suddenly frequency and does not evaporate in through going inside of compressor wiring ,

First it hit this Elbow and we have tension from changing temperature there .

MBC

[Peter_1]

Perhaps contact better Bitzer Germany... they want to know special issues with their machines.

[mbc]

Hi peter


I asked 2 or 3 times some question but they referred me to his inter national manager and he is no response .

last time I asked about R - 410A , Can I use in HSN types ?

[GHAZ]

Hi I think its when the compressor is fully loaded to quick it causes vibrations and the demister pipes crack

[mbc]

Hi

We should believe our community power ( this site )

After more than 5 E-mails and in the end I pointed here , today Bitzer response for my question .

MBC

[NH3LVR]

What was their response?

[mbc]

Hi

this is :


Thank you for your interest in BITZER Products.
HSN machine usually can’t be used with R410A due to the machine- design pressure and the high discharge pressure of R 410A
More information you can find under
https://www.bitzer.de/shared_media/h...-GB/index.html
https://www.bitzer.de/websoftware/De...=en&country=gb

[jannickz]

Although the compressors are being opened for the first time, it's possible they experienced fatigue due to vibrations, pressure fluctuations, or other operational stresses during their service life. This fatigue could have contributed to the eventual failure of the demister pipes. It's also important to consider any external factors that Ultra high-speed angular contact ball bearings might have caused damage during transportation, storage, or installation. Even minor impacts or improper handling could have contributed to the cracks.