Consultation on dry gas sealing issues of centrifugal compressors
Thread Content
The second-stage primary seal of the compressor of this unit is composed of a double-end dry gas seal and a labyrinth seal. When the unit was stopped, it was discovered during nitrogen air sealing that there was leakage at the connection between the back of the turbine and the shaft? What is the reason for this situation? Is the sub-labyrinth seal allowed to leak?
The primary sealing gas should enter the body through the labyrinth seal, while a small amount of sealing gas enters the torch system through the sealing end face. Check to see if the sealing end face is damaged. How is your level one leak gas flare volume?
How do I remember that there is leakage when the dry gas seal is shut down? Did you remember it wrong? Ask God for answers
Ours does not have a bleed torch. The dry gas seal is followed by a comb seal, and the leakage is quite large.
The dry gas seal is a dynamic pressure seal. It is normal for the dry gas seal to leak when parking: lol
You enter the labyrinth seal after the dry gas seal. Then the atmosphere is directly exhausted after the labyrinth seal? No matter the dry gas seal or the labyrinth seal, they only reduce leakage to a certain extent, but they are not leak-free.
Is the air seal leaking when the car is stopped? The dynamic and static rings of the dry gas seal are closed under the action of the spring when the car is stopped. Is the auxiliary seal ring damaged?
Yes, the labyrinth seal directly exhausts the atmosphere, the dry gas seal is connected in parallel, and then the labyrinth seal. At the current parking stage, the leakage volume behind the second stage and first level nest is quite large. The labyrinth seal allows a certain amount of leakage, but now the regulating valves of the sealing gas have been fully opened.
Now it's the air leakage in the labyrinth, or it may be the European ring. The dry gas seals are connected in parallel, so what is the use of the second dry gas seal?
Only when the dry gas seal rotates far, the sealing air is pumped into the dynamic and stationary rings to form a rigid air film to achieve the purpose of sealing. When you are parking, the dry gas seal dynamic and stationary rings are closed. Is the auxiliary sealing ring leaking, causing large leakage?
It may be that the sealing surface is not closed tightly, or the O-ring secondary seal is damaged. The labyrinth cannot be completely sealed, so the above two reasons may cause leakage gas to leak out of the machine through the labyrinth. If the sealing surface is not closed tightly, it does not necessarily mean that the sealing surface is damaged. It may be that the push ring is stuck and cannot move freely, causing the dynamic and static rings to fail to close.