Recent content by bob330

EdStainless, The stuff on the Al website simply looks like typo stuff where they apparently took austenitic SS CTE data and gave out those same numbers for other materials like 2205 and 440A stainless which we all know do not expand nearly as much. I didn't check too many other materials but...

Thanks to all you guys.

Hi All, I noticed that the specification for 310SS allows up to .25 wt% carbon which is three times that of a standard grade like 304. Would it be fair to say that this alloy is extremely amenable to being sensitized during welding? Is there any information on this in the technical...

Hi Guys, Near the beginning of the Section VIII code section UHA, it referes to appendix HA for tips on the usage of stainless steel. However, I could not find appendix HA. Does anybody know which document to locate this from? Bob

Thanks sreid, I wonder how many metallurgical folks have been fed severe misinformation on that A-L website. When they said that that 440A had the same thermal expansion properties as austenitic SS, I knew something was wrong. Add that to them showing the 2205 to have the same CTE as...

Hi Guys, What is the difference between Section VIII div 1 and Div 2? Also, what is the differnce between allowable stress value "S" and design stress intensity "Sm"? Thanks, bob

Also Guys, The CTE data for 440A stainless steel is also completely wrong. I would recommend you all avoid the AL website for technical information. Bob

Thanks Guys, The Alleheny Ludlum site referenced above is all screwed up as they report CTE values for 2205 as being identical to those of 316SS /317 SS. Why does this stuff happen? Their site is very misleading. There is no excuse for this nonsense. Bob

Thanks, This does not make a lot of sense, I have several separate references that show 10,000 and 100,000 hour rupture data for 316, 316L and 321 SS and the 316L is equal to or superior in rupture strength to 321SS at all the higher temps 900F-1500F and only slightly iunfereior to regular...

Guys, Where in the ASME code would I find allowable stres values for common austenitic SS materials at higher temperatures like 900F-1500F. Does the code mandate lower allowable stress values for the "L" grades versus the regular grades and how does 316L compare to say 321SS or 347SS? Bob

Thanks Guys, Stagnancy and fouling are no doubt the big concerns. I did want to clarify someting here that I was not celar about earlier. The tube side service is cooling tower water and the 1000ppm chloride is a maximum potential condition and in the past has only reached these levels...

Thanks to all of you guys, We are going to do our first internal inspection at a one year time frame instead of the origianlly planned 1.5 to 2 year plan. This will give us at least somewhat improved piece of mind. Although we have not really observed caustic SCC in this vessel, the...

Thanks Guys, I had a typo there......sorry. Actually I am writing a German to American alloy translation page and UNS S31725 is essentially equivalent to German alloy 1.4449. I wanted to add a comment in my guide as to whether or not the ASME recognized all the US equivalents of the German...

Hi Guys, I was wondering if 317LM (UNS S31735) and 317LMN (UNS 31726) are ASME pressure vessel code approved or recognized materials available with "SA" designations? Bob

Hi All, For heat exchangers, how does the thermal conductivity of duplex grades like 2205 compare to that of austenitic grades and plain carbon steels? Bob