John Crane type 28 is a compressor seal (non-contacting seal). We are talking about JC type 48C/S48SC. It's a full contact dry running secondary containment seal.
In case of considering using a non-pressurized secondary seal, Is it really necessary N2 buffer? I think a N2 buffer is imperative If you need zero emission. Gas seal is too expensive. I recommend a secondary containment dry running seal and keep the liquid seal as a primary one, configuration...
What's the best solution for light hydrocarbon(LPG, propane, etc.)centrifugal pump sealing? I use dual seals API Plan 11/52, but I think It is very expensive,not so reliable and the operation is not so simple. I have read some papers about dry contacting secondary containment seal. I would like...