API 682 solution not understood
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Option 52: When the primary seal leaks and the pressure in the seal fluid tank rises, and the external seal leaks as well, causing the liquid level to increase – could you explain this to me?
Scheme 52 features a pressure-free seal, meaning that the external auxiliary seal is at no pressure or at a lower pressure than that of the main sealing chamber; it is usually connected to a flare. When the main seal leaks, the medium in the high-pressure main seal chamber flows into the outer seal chamber, causing the liquid level in the seal fluid tank to rise and triggering an alarm. At the same time, due to the throttle orifice plate at the gas outlet of the seal fluid tank, the pressure within that tank increases as well. But “leakage at the outer seal, rising liquid level” doesn’t make sense.
A leak in only the outer seal will not cause the liquid level to rise; the inner seal must also be leaking, it’s just that you haven’t noticed it
If you are absolutely certain that the inner seal is not leaking and only the outer seal is leaking, here’s an explanation for you: the outer seal indeed has a leak, but it’s not severe, and the inner seal is indeed not leaking. When stopping the pump, you noticed leakage at the outer seal. You checked the liquid level, and then thought that maybe the leakage would stop if the pump was started again. So you started the pump, but it continued to leak; meanwhile, the liquid level rose. I can think of no other possibilities besides that
First, determine whether the process medium is a liquid or a gas at atmospheric pressure? If it is a liquid, a leak on the process side causes the level to rise, while a leak on the atmospheric side causes the level to drop. If it is a gas, a leak on the process side leads to an increase in pressure, whereas a leak on the atmospheric side results in a decrease in pressure.
Uh, it can’t happen at the same time? Generally, the 52 scheme involves light hydrocarbons; the pressure increases at atmospheric pressure. Does \"atmospheric pressure\" refer to this when measuring leaks?
This means that the inner mechanical seal is also leaking, and the medium has seeped into the tank
The 52 system is a non-pressure flushing system, with the pressure on the medium side being higher than that of the sealing fluid. When there is a failure on the side of the sealing medium, the liquid level in the sealing tank rises. A leak in the primary seal (i.e., the inner seal) cannot be detected from the outside, while leaks in the secondary seal are easily visible. As a result, it might be assumed that only the secondary seal is leaking, and it could be mistakenly believed that the primary seal is intact, even though the pressure in the storage tank increases. It's just my personal opinion; feel free to correct me.