Anyone had the expience of carbon ring seal used for centrifugal compressor and would like to give me some comments on the following issues.
In these years we always experienced many issues of carbon ring seals on our integrally geared centrifugal compressors. The main issues on the carbon ring seals are as follows:
- Broken detent pinè then carbon ring was rotated together shaft in the seal housing.
- The lip seal of carbon seal is completely worn out and subsequently the carbon ring was stuck at this positionè cannot float so as to result in high vibration.
- Stuck carbon ring in the seal housingè then uneven wear on the carbon ring è finally resulted in machine trip caused by high vibration.
- Worn detent pin hole on the carbon ringè then carbon ring was unable to freely float in the seal housingè finally resulted in rubbing with shaft and consequent machine high vibration trip.
- These pictures of current carbon seals are attached below for your reference. .
- I don’t find any information of the damaged carbon seal in the compressor manual, but I saw the following description of carbon seals in the manual of another compressor that the attention must be paid to be direction dependent position of the detent pins and from the picture, it looks like the detent pin position should be set at horizontal direction but not like our current mounting position that the detent pin is put at basically vertical direction with an angle offset of 11.5 degrees towards left or right.
Could you kindly help on the following questions:
- The detent pin must be put at horizontal direction ( 3’ clock or 6’ clock)? -----If this is necessary during the mounting, then could you kindly tell me what the real reason is ?
- The detent pin must be depended on the shaft rotation direction? ----If this is necessary during the mounting, then could you kindly tell me what the real reason is?
- What is a proper length of the detent pin? Because we always find that the pin is broken or worn, we have to machine some pins for the mounting of new carbon ring during the urgent cases. It is better if you can tell me the actual requirement on the length of the detect pin.
- We also have carbon ring (from your company) designed on the Siemens compressors, but till now we haven’t experienced any issues on these machines. I believe the current issue should be caused by some reasons besides carbon seal self, such as carbon seal installation….. Could you kindly teach me that details should be well followed during the actual installation, otherwise it will be able to cause those issues mentioned above.
Your kind help on my questions will be very appreciated. Looking forward to seeing your reply