![]() ![]() 5 Variations due to atmospheric conditions.This constant is used in the calculation of radiation pressure, which aids in the calculation of a force on a solar sail. Billions of years ago, it was significantly lower. In the past 400 years it has varied less than 0.2 percent. ![]() ![]() The solar constant is an average of a varying value. The solar "constant" is not a physical constant in the modern CODATA scientific sense that is, it is not like the Planck constant or the speed of light which are absolutely constant in physics. It is measured by satellite as being 1.361 kilo watts per square meter (kW/m 2) at solar minimum (the time in the 11-year solar cycle when the number of sunspots is minimal) and approximately 0.1% greater (roughly 1.362 kW/m 2) at solar maximum. The solar constant includes radiation over the entire electromagnetic spectrum. It is measured on a surface perpendicular to the rays, one astronomical unit (au) from the Sun (roughly the distance from the Sun to the Earth). The solar constant ( G SC) is a flux density measuring mean solar electromagnetic radiation ( total solar irradiance) per unit area. I am curious if anyone has used it recently too.Solar irradiance spectrum at top of atmosphere, on a linear scale and plotted against wavenumber. If the flux was removed before the weld was capped off.sugaring was unavoidable, but if it stayed on, you really had a nice looking weld. I think they called it "scuttle-root" but that was such a long time ago and I have never seen or heard about it being used since. The higher ups wouldn't go for it and there were miles of pipe lines to joined so we ended up purging every joint with argon. As long as the flux (similar to stainless stick rods) remained intact through out the 2 pass weld.and then the flux was removed (it came off the welds easy enough).I would have thought it would have been alright as heat settings were similar as if we were purging the pipes with argon. Actually, a sound root pass was possible, however, the resulting flux covering on the interior of the pipe joint was undesirable by the Client and thus the "experiment" was scraped. It was difficult to see the puddle (with the flux floating around and such) and the results were varied. A few of us pipe welders were given samples of the rod where we ran 3 or 4 joints (apiece) on 4" and 6" stainless pipe (schedule 10). ![]() I had some past experience with a flux-covered Tig wire (316L) which was introduced as a cost saving measure at a paper mill in New England over a dozen years ago. Again thanks to all and any input from others with thoughts on this would be greatly appreciated. I confess that my implicit faith in the code is a tiny bit shaken. Jon,my friend, I am anxious to hear why this is not an essential variable please tell me this is errata, although the 2000 Edition of IX reads the same. As far as Potable is concerned I think anyone could see that small particles of "glass like" residue flaking off into eyewash service is unacceptable. I am not an engineer or a chemist, and if I am wrong in being apprehensive I'd appreciate it if someone would enlighten me. Demin water service for Ion Exchange I have always believed to be quite sensitive to contamination. My biggest concern is the residual mess unaccessible in piping ,and the impact on system performance. I personally have never seen it used to where it would meet even Visual inspection. Andy, the article by Walt Sperko is just what I needed to make the case that there are more reasons to avoid solar flux than try to use it. Gentlemen: Thanks so much for your kind responses. ![]()
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