Mechanical seal issue
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Is the pump seal in this diagram connected to cooling water? The medium being transported is saline, at ambient temperature. When it was first installed, cooling water was not connected; the seal area became a bit hot, and there was a burnt smell.
This interface is present on both sides of the mechanical seal; it’s a very small centrifugal pump, with a motor power of only 3KW
This post was last edited by 3983596_FPPZ on 2018-11-2 at 23:01. It seems to be the Plan11 self-cleaning scheme; there is no flushing flow in the sealed chamber, and the gas cannot escape, which results in heating due to almost dry grinding. Check whether there are pressure tapping threaded holes on the pump outlet flange or the elbow; if so, connect them to the fitting on the seal using a pipe. Connect whichever side is more convenient to create a circulation path. If there are no threaded holes near the pump outlet flange, it is best to drill one ； Or, if dilution with salt water is not a problem, it is also possible to seal it directly and connect it to cooling water.
I don’t know how many sealing sets are inside; if it’s one set, then it’s a single seal, and if the opening isn’t sealed, fluid will flow out after the pump is started. In the case of a double-seal design, that is, the PLAN54 scheme, there will be no leakage during pumping; however, after operation, the rear seal undergoes dry friction and the high-temperature O-ring burns out. The two ports need to be connected to external flushing fluid, and the pressure of the returning water must be higher than the pressure inside the chamber.
It is likely a double-end face seal, and cooling water should be supplied before starting the pump. Since the photo on the opposite side wasn’t taken, I can only guess: if it’s a single unit, wires are generally not used to secure the pipes here, as pipelines returning from the pump outlet usually don’t use this type of construction. If water is not allowed to flow through the double seal, the outer seal will grind dry, resulting in the burnt smell mentioned by the poster
It is external cooling water. Operating without cooling water may have already caused damage to the skeleton seal between the gland and the shaft sleeve
The side opposite to where the photo is taken is the same.
It only ran for ten minutes. For the external cooling water, does it need to be connected on one side only or on both sides?
It makes sense; I agree with this view as well.