Regarding the pump flushing plan, PLAN52 discharge port

It has little to do with the medium~~~ Within the design framework, when there is a leak in the internal seal, the sealing fluid enters the medium side through the leak; as a result, the liquid level in the sealing fluid tank drops, the level switch activates, and a L or LL signal is sent. Once notified remotely, the pump is switched over~~~ Therefore, no medium should be able to flow out of the sealing fluid tank~~~ Unless the leak is severe enough such that most of the fluid in the tank ends up inside the pump chamber, causing the medium in the pump to flow back again~~~ That would constitute an accident due to negligence. In my opinion, proper management can eliminate the need for such drainage systems (except for toxic or hazardous media)~~~~

Scheme 52 is a pressure-free scheme; therefore, a pressure relief line or vent is usually connected to the upper part, while the vent at the bottom is generally not connected to a dense arrangement of outlets.

First, you choose the PLAN11+52 scheme; in such cases, the medium is either toxic or harmful, or it operates at high temperatures, and therefore a closely packed system needs to be added. Moreover, the selection of oil coolers needs to be carefully considered in the flushing plan for high-temperature medium pumps. Our unit once had a high-temperature gasoline pump that used the PLAN11+52 design; moreover, the oil cooler chosen was of insufficient capacity. As a result, the temperature of the cooling water was often high, and steam appeared in the drainage fluid. The flushing medium also vaporized at the mechanical seal area, causing the seals to emit screeching sounds frequently, and several sets of mechanical seals were damaged as a consequence. Later, after expanding the cooling water pipeline of the oil cooler, I increased its heat exchange area from 0.6㎡ to 0.8㎡; since the renovation was completed in 2017, the pump has been operating well.

Is there a cooler in the 11+52 plan? I was a bit confused by what I heard. Note: The tank in scheme 52 is not a heat exchanger; the heat exchange there relies mainly on the thermosiphon effect, which is why it’s called a siphon tank. If it’s under high-temperature conditions as you said, then it should be changed to 21 (or 23) + 52

52 is mainly used in light hydrocarbon media; in the event of a leak, the upper part is connected to a flare for combustion, and the liquid at the lower part generally does not require tight sealing. If the medium is toxic and hazardous, tight sealing can be considered, but in such cases, a pressure-rated sealing system such as 53, 54, etc., is usually chosen

It is generally unrelated to the medium; it’s just the sealing oil that is discharged. However, if there are problems with the seal on the medium side, some of the medium may enter the sealing oil tank as well, but in very small amounts. If the medium is highly hazardous, it is recommended not to discharge it directly there, but instead to direct it into a waste liquid collection tank.