Dry gas seal damage problem
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The leakage of the primary sealing gas at the driving end of the dry gas seal of the current circulating hydrogen compressor has fluctuated since yesterday, with a fluctuation range of 16.0---18.3KPa. The primary sealing gas of the dry gas seal has a demister (automatically discharges condensation every two hours), electric heating, and a high-precision filter (used for 3 months, differential pressure 3.0KPa). The purge air is now changed to amplified air. Prepare to calibrate the instrument system today. Is the seal damaged? In addition, please discuss the normal fluctuation range of the dry gas seal primary sealing gas leakage.
The instrument was checked today and there is no problem. The demister was manually drained for 15 minutes. Currently, the leakage of the primary sealing gas is stable at 19KPa. A small leak was found on site and has been dealt with. I would like to ask colleagues for advice on how to find and deal with it. What are the causes of fluctuations that affect the leakage of primary sealing gas? What is the normal fluctuation range of the leakage of primary sealing gas in dry gas seals?
The main seal leakage of our circulating hydrogen compressor is very stable, at 190-192m3/h. Under normal circumstances, the focus is on the differential pressure of the main seal, which cannot be too large. Ours is around 256kpa. Waiting for other answers
Reply to the dry gas seal used in building 3#. The differential pressure between the first-level sealing gas and the balance pipe is controlled at 80KPa. This differential pressure mainly controls the injection amount of the first-level sealing gas. There is no change in the current injection amount.； The differential pressure of the filter is only 3.0KPa (it has just been used for 3 months and is still far from the upper limit of the design value of 23.6KPa. ； However, the differential pressure of the demister increases slightly, but it is also far from the upper limit of the design value. please advise
It is possible that the dry gas seal was damaged during installation or the method of drying and putting the seal into use was incorrect. The high point should not matter. It is recommended to strengthen the analysis of leakage gas! This post was last edited by leisure929 on 2008-3-3 11:54 ]
If the level one leakage fluctuates, it may be: 1) Fluctuations in primary seal leakage caused by fluctuations in primary air inlet pressure 2) Changes in the amount of secondary air inlet 3) Changes in primary seal clearance caused by axial movement of the compressor rotor causing changes in leakage
Agree with the first two points of Floor 6’s point of view. Pay attention to the relationship between process stability and fluctuations in seal leakage. The axial movement of the compressor rotor can be checked, but it generally has little to do with the fluctuation of seal leakage.
For the demister, you are using a Flowserve seal. The dry gas seal chain is mainly set on the pressure or flow rate of the primary leakage air. If there is a fluctuation, it may be a fluctuation in the process. If it continues to increase, the seal must have been damaged and started to fail slowly. You can also observe whether there is any change in the air intake of the secondary seal on this side of the high-reporting seal, and make a comprehensive judgment.