dry gas seal
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Excuse me, which one of the dry gas seal dynamic ring and static ring relies on the impeller? Where does the nitrogen entering the cavity go?
This post was last written by du* Edited by ngdx on 2009-11-15 16:11 The moving ring rotates with the axis. Dry gas seals are generally three-level seals. Generally, after the machine is running, the main seal uses process gas, part of which enters the cavity and part of which enters the vent pipe network. Only nitrogen is used for the main seal before starting up. Nitrogen is always used for the secondary and tertiary gas (isolation gas). Part of the secondary gas and part of the main sealing gas enter the venting pipe network, and the other part and the tertiary gas (isolation gas) are vented on site.
The dry gas seal is a non-contact mechanical seal. The structure can refer to the mechanical seal. That is, a part of the moving ring close to the impeller pump is discharged by the dry gas seal. Normally, a very small part may enter the pump body (if it is too large, it will be difficult to start the pump).
Generally, dry gas seals for compressors have the moving ring close to the impeller. Most of the nitrogen entering the cavity enters the process system, and a small part leaks through the first-stage seal and is vented.
Generally, dry gas seals for compressors have the moving ring close to the impeller. Most of the nitrogen entering the cavity enters the process system, and a small part leaks through the first-stage seal and is vented.
Then there is such a problem. I read the dry gas sealing information and said that the pressure to open the dynamic pressure tank must overcome the spring force of the static ring and the left and right force of the medium. If the moving ring is close to the impeller, it should be that the left and right forces of the medium are on the moving ring.
It’s best to look at flow charts and structure diagrams, John Crane’s are very classic!
The moving ring is close to the impeller. As for nitrogen, what kind of seal should you look at? Dry gas seals are now common with double-end seals and middle air inlet series seals. General nitrogen is used as a first-level sealing gas and enters the process gas when the machine is turned on. When it is normal, you should use process gas. The secondary seal is always nitrogen, and for double-end seals a small amount can enter the process gas. But most of them are still vented, and for series seals, most of them are vented. Of course, some of them will still be vented to the atmosphere with the isolation gas. As isolation gas, some of our factories use instrument air, and some use nitrogen. Basically, they use atmospheric venting, and some use lubricating oil respirators.
The moving ring is close to the impeller and relies on the sealing end face to seal the gas. Generally, process gas is used, but it depends on the composition of the process gas. Some cannot use process gas. I have data that I can't upload because I don't have enough permissions. Can't help you anymore. Otherwise, you will understand after reading it.
So when the compressor is not turned on, but the primary seal is not stopped, does it all enter the system? This is when the compressor just starts to warm up at low speed. If the rotational speed cannot form a normal air mold, isn't there friction in the dynamic and static rings?
Turning has a greater impact on dry gas sealing.