Leakage from Leak Detection port of Double seal.

[shyamshins]

thread819-380230
Dear sir with ref. to above thread we have one more seal failed at our plant.
Leakage was observed from Leak detection port from outboard side of agitator seal.
Barrier fluid used is Duraclear of Flowserve make.
Process in agitator is Carbo oxhilation. Pressure maintained in reactor is 30Kg/cm2 & press. maintained in syphon pot is 42kg/cm2 ,
Does such a high pressure difference allowable in agitator & syphon pot?

No leakage is observed till pressure in reactor is maintained between 20 to 30kg/cm2 & syphon pot pressure is 42kg/cm2, but if pressure in reactor drops below 20kg/cm2 (wherein syphon pot pressure is 42kg/cm2) which is during transfer of batch, leakage is observed from leak detection port i.e. from outboard of seal.

Is it mandatory to maintain delta P at 2kg/cm2 in order to avoid seal leakage? or Plan 53C is only solution?

Is there any system other than plan 53C to reduce & increase pressure of syphon pot as reactor is operational?

 

[RHurst]

If your seal pot (siphon pot as you described) stays at a constant 42kg/cm^2 (~597 psi) then the differential pressure on your outboard seal face is also constant. If you are leaking barrier fluid (duraclear) to the atmosphere during your transfer then it is likely due to some dynamic going on during that transfer process. Some examples could be excessive shaft movement/runout, vibration, axial shaft movement, etc.

Concerning the previous thread's poster who was adamant that a plan 53C auxiliary setup is the right thing to do, this is incorrect. As long as your outboard seal is designed for the differential pressure of the barrier system, then everything should be fine. Typically 53C systems are deployed due to design implications with the inboard seal faces.

Your previous posts mentions that you have observed vibration on this system before. Is it still present? What is the magnitude of this vibration?