Two stage Sabroe

[Ian B]

I have been doing a survey today on an old Sabroe pack. The compressors are TSMC 116S and are running on R69L. The compressors are over twenty years old, does anyone have a manual for these? and how can i tell that my interstage saturated pressure is most efficent. I seem to remember there was a calculation for working out the interstage pressure, something like ''the squre root of the sst x sdt''. Any ideas and feed back would be most welcome.

Ian

[US Iceman]

and how can i tell that my interstage saturated pressure is most efficient. I seem to remember there was a calculation for working out the interstage pressure, something like ''the square root of the sst x sdt''.

The equation you are describing is not necasserily the most efficient, it just allows you to find the same pressure ratios for both compressors. The actual equation is square root of (Suction Pressure of the low stage compressor X Discharge pressure of the high stage compressor), where both pressures are in absolute.

The most efficient point of operation is one that allows you to minimize the total power input. That might mean you raise the interstage pressure and lower the high stage discharge pressure.

[Pooh]

IanB
easiest way is to plot the conditions you have on Coolpack and then play with the interstage pressure and keep checking the calculated COP.
Ian

[Ian B]

Hi Ian,

Yeah i tried Coolpack, but my version doesnt have R69L(R403B) in it. Does your version?

Ian