Mechanical seal Leak problem
Mechanical seal Leak problem
(OP)
I would like to ask anyone who has any experience with flowserve plan11/53B seal. In the drawing, it is instructed that the drain plug should be removed before operation, unfortunately the plug was not removed and the equipment was running for 3 months in this condition, then after 3months leaks was discovered in the shaft part beyond gland bushing. The drain plug was then removed but the leak in the drain was unacceptable. The green highlight in the attached drawing shows the path of the leak from the faces to the drain, but since the plug is not removed, it seems the green part was subjected to pressure (12barg). When the seal is dismantled, the gland bushing has two cracks opposite to each other. And the rotating face at the left side with the highlight has some deposit of carbon/rubber material (I think O-ring). The technician said that it can be because of misalignment but I cannot accept it since we do proper alignment of pump and motor, and there is no vibration experienced during the 3 months operation.
Questions:
1.What could be the reason for the leaking? Can this be because of the drain plug not removed?
2.Can the leaks be related to the broken gland bushing?
I hope someone could help me regarding this. Thank you very much.
Questions:
1.What could be the reason for the leaking? Can this be because of the drain plug not removed?
2.Can the leaks be related to the broken gland bushing?
I hope someone could help me regarding this. Thank you very much.





RE: Mechanical seal Leak problem
RE: Mechanical seal Leak problem
Your seal failure is not because the drain plug was in nor the broken bushing. Looks like this is an overhung impeller and perhaps cavitation has damaged the bushing. Also check the pressure trends on your plan 53B because it seems you have a connection for Plan11. Do you use this connection?
A few photos will help us solve your problem.
RE: Mechanical seal Leak problem
We get low pressure alarm on seal plan. The faces of the outboard have some scratches according to vendor inspection report. the rotating face of inboard seal which I highlighted has some material deposit that seems to become embedded in the highlighted area. vendor said it is due to one side rubbing. the spring in the inboard seal part has also deposits of carbon particles, probably from the process fluid (hydrocarbon). 12 barg in the green area is just what goes to my mind, now I understand things better. I'm not sure if plan 11 was used. Maybe tomorrow I can provide some photos.
Thank you very much for the help.