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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

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

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

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

Hi All, Given a certain diameter rod and amperage, is there more penetration into austenitic SS or plain carbon steel materials when welding. I guess another way of asking this is to ask whether or not root face heights (at weld prep) should be made bigger or smaller for SS as compared to...

Hi, Will 316L tend to pit in stagnant seawater at ambient temperatures if there is no fouling deposits or crevices present on it? If not, would we expect to see issues with fouling present? Also, would anybody expect to see pitting for tube side water in an HE application with up to...

Hi All, Is there any reason to believe that a given carbon steel vessel girth weld made by the SMAW technique with 350F Preheat would be any more susceptible to caustic SCC than the same vessel welded by a SAW technique. I guess another way of re-phrasing this question would be to ask if...

Hi All, After weld repairing a pressure vessel in caustic service here, Brinell hardness readings were taken in the weldmetal, HAZs, and base metal on the inside of the vessel. I have not observed the size of the indentions but regardless, I suspect it may be best to grind these out due...

Hi All, Is caustic SCC of carbon steel intergranular or transgranular. Also, with most SCC processes, increased metal hardness leads to increased cracking susceptibility. However, I read somewhere (trying to find link) that this is not the case with caustic SCC of CS and that softer steels...

Hi All, The NBIC code refers to alternate techniques allowing the avoidance of PWHT on pressure vessels such as the half bead technique or controlled deposition techniques but fails to explain exactly how these techniques are to be done. Can anybody here elaborate on the details of these...

Greetings All, I have a question about actual cases where pressure vessels have catastrophically failed (Deaerators, paper mill digesters, etc). With cracks present in the vessel, final sudden failure could occur via two means. One is by a fast cleavage fracture where K1c or J1c are...

Hi All, I was wondering what welding techniques are optimal for building up thinned piping without burning through. In other words, what techniques allow you to lay down good filler with very minimal penetration? I'm looking for information not just on process (GMAW,GTAW,SMAW) but also on...

Hi All, With it being known that carbon steel can suffer SCC in aerated anhydrous ammonia, is it possible that this could occur in oil that is contaminated with a small amount of anhydrous ammonia? Thanks, Bob330

Greetings All, Although it is well known that electrolyte turbulence and flow help to mitigate pitting in austentitic stainless steels, little to nothing is ever said about the influence of flow or flow rate on CSCC susceptibility. Is there evidence to believe that flow rates can have a...

Greetings, Recently, I was asked to examine some near pure (1XXX) series aluminum cooling fins that were reportedly not conducting heat very well. The fins (on 304SS tubes) have plant environment air blown on them by a large fan and this air is suspected to have a significant amount of...

Greetings, Are austenitic stainless steels subject to CSCC in Hydrochloric acid that is not contaminated with chlorides coming from alternate sources than the acid itself (like NaCl)? My thoughts were that the acid in water should disassociate into hydronium ions and chloride ions the...