Hi Chris
On (30 Aug 96) Chris Harper wrote to Alec Cameron...
 CH>  AC>> and be prepared to run at the lowest practical temp and pressure.
 CH>  CH>> Why?
The lower the steam pressure and temp, the less severe is the extent of
erosion and corrosion inside the bolier.
                                 
 AC> In a boiler pressure and temp are usually bracketted. Utility boilers
 CH> run
 AC> at about 2400 psi and 1100 deg F.
 CH> I don't intend on going anywhere near those figures! At least not 
anywhere
 CH> in the near future!
I quoted those figures not for your approval! but to indicate the aggressive
conditions inside the steel boiler drums and water tubes. At times, the local
demineralising plants at power stations cannot handle the rapid loss of feed
water quality, and road tankers would arrive daily with distilled water to
dilute the salty soup being cooked in the boiler.
The severe conditions I remember, were with coastal generating stations which
used ocean or river water for condenser cooling. The condenser running at
negative pressure [vacuum] there would sometimes be water ingress due to 
eaks
in the condenser structure. Counter measures included dumping truckloads of
sawdust into the water canal, the sawdust plugging the condenser leaks then
swelling so improving the temporary "repair".
Cheers......ALEC
... ....Horsepower was a wonderful thing when only horses had it
--- PPoint 1.92
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