Literature on Ofeldts?

A special section just for steam engines and boilers, as without these you may as well fit a sail.
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fredrosse
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Re: Literature on Ofeldts?

Post by fredrosse » Mon Oct 30, 2017 11:32 am

"I was planning on using 304 stainless....."

304 or 316 stainless steels, and many others, are prohibited in steam boiler wetted parts, including the drums and steam generating tubes. This is clear in the ASME boiler and Pressure Vessel Code, and has been discussed several times within this forum.

The only way to legally use stainless steel in a power boiler is to maintain extremely low TDS in the boiler water, which is just not a reasonable option for a hobby boiler.

For example, power plant boilers usually must maintain a fraction of a Part per Million (PPM) total dissolved solids, and stainless steel power plant boilers must maintain less than 1/1000th of that contamination, usually the Part Per Billion range. Stainless steel power plant boilers are rare, the only one I worked on was Eddystone, which had design conditions of 5000 PSI steam, 1200F. I have never come across another power plant boiler with stainless steel generating tubes.

Typical lake and drinking water in the USA typically ranges in the 50 to 500 PPM dissolved solids, and in my steamboat, with concentration of solids due to the evaporation of steam, I usually have around 800 PPM TDS. That is OK for a 200 PSI steel boiler, but totally unacceptable stainless steel wetted parts of the pressure vessel.
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