Should the sealing oil be injected into the hot oil pump before or after it starts up? Why?
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Should the sealing oil be injected into the hot oil pump before or after it starts up? Why?
We usually introduce seal oil after starting the hot oil pump; its functions include sealing, flushing, and lubrication. However, in many refineries, seal oil is not used at all, mainly due to cost considerations, though there is no harm in using it either.
Our oil seal has remained open, and the backup pump is also kept running, mainly to enable the equipment to operate for extended periods of time
Reply to 2# flying-mooding: If it’s a radial feed pump, do you also open the oil seal? That would be amazing;P
Reply to 4# lijianhuai: Moderator, could you be more specific? Thank you.
Hot oil pumps require the injection of seal oil during the preheating process, as lubrication, sealing, and cooling are also needed during this stage! In my opinion, there are no issues related to economic benefits or costs associated with injecting sealing oil! After the sealing oil is injected, it still returns to the entire large system, where it is then reprocessed together with the component oils or sent out of the plant – it isn’t lost!
Reply to 2# flying-mooding: Our company has been using sealant all along, with no interruption; and if they don’t use sealant, it must be due to cost considerations! ! That’s so funny, right?
Sealing oil primarily serves to flush out impurities, lubricate seals, and reduce temperature. Sealing oil should be put into use before starting the pump. Sealing oil plays a role in ensuring safe operations; in the event of a leak, the sealing oil leaks first, thereby preventing high-temperature oil from escaping. Our standby pump has oil sealing turned on all the time. Use seal oil whenever possible (it is safe and helps the mechanical seal to operate for a longer period of time)
Reply to 8# jm1970: I fully agree with the use of seal oil. The hot oil pumps in our facility do not use seal oil, and seal leakage often occurs at the beginning of operation; we plan to start using seal oil in the next cycle!
Our unit has been using seal oil for the hot oil pump. The seal oil should be activated when preheating the hot oil pump. The functions of seal oil are sealing, cooling, lubrication, and flushing. Many people recommend using the medium itself or a similar medium after cooling it as the sealing oil; our unit uses the middle stage fluid as the sealing oil.
For hot oil pumps, the seal oil should be kept on when they are in standby mode to prevent leakage of the medium; the amount can be kept relatively small. After the pump is started, the valve for injecting seal oil can be opened wider. If you are unable to determine the exact amount of oil to inject, you can first close the valve at the injection point and monitor the pressure there; this represents the pressure in the pump’s sealing chamber. Once that pressure is known, open the seal oil valve again. When the pressure of the seal oil is slightly higher than that of the sealing chamber, it means there is sufficient seal oil available.