Confusion on a book's term

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Okayyy. In "The Procedure Handbook of Arc Welding" by the James F. Lincoln Foundation, section 6.1-12, the first paragraph of the second column... "... For example, three-o'clock groove welds are more sensitive to cracking than flat-position groove welds." What in the world does it mean by 3-oclock? Does it mean a horizontal groove joint (where my welding  work angle would be slightly higher than horizontal), or is my brain just not functioning correctly today? Thanks for any input!John
Reply:Ok, maybe in pipe welding?http://www.kobelco-welding.jp/images...tlight/011.jpg
Reply:Its common in pipe welding to refer to welding position by the hands of the clock 12 o'clock being top 6 being bottom and so on.  I would assume that's what there saying there.  I'd like to here more about why the 3 oclock position is more succeptable to cracking.
Reply:Originally Posted by JMcL213Okayyy. In "The Procedure Handbook of Arc Welding" by the James F. Lincoln Foundation, section 6.1-12, the first paragraph of the second column... "... For example, three-o'clock groove welds are more sensitive to cracking than flat-position groove welds." What in the world does it mean by 3-oclock? Does it mean a horizontal groove joint (where my welding  work angle would be slightly higher than horizontal), or is my brain just not functioning correctly today? Thanks for any input!John
Reply:@ JMcL213 - in the 14th edition (May '00), the identical text appears.  The sentence you quoted is preceded by "The welding position and its influence on bead size, heat input, number of layers, etc., has a direct influence of the cracking tendency".   Furthermore, contextually the paragraph is originally adopted from two articles appearing in the Welding Journal (1964)....'Welding Cracking Under Hindered Contraction:  Comparison of Welding Process' and 'Delayed Cracking in Steel Weldments.'Instinct tells me we are not talking about welding pipe in this case.  Instead, the 3 o'clock may be referring to a standard fillet weld (T-joint) where the attack angle of the electrode wrt the joint is approx at three O-clock.  Visually cross-section a t-joint and imagine the electrode position IRT the vert/horz surfaces and this makes sense.  Perhaps by horizontal groove joint, the author really means an open-groove (butt joint)?   An image, in this case, would have aided the reader in the interpretation.   The JFL Procedure Handbook of Arc Welding is the absolute cat's meow for all welders, IMHO."Discovery is to see what everybody else has seen, and to think what nobody else has thought" - Albert Szent-Gyorgyi
Reply:ManoKai,With the information you supplied I was able to track that wording down in my 12th Edition.  It's mid way down the first column on page 6.1-10.  (I guess I missed it on my first skim thru section 6.1) It's the last paragraph under the heading "Observations on Factors Contributing to Cracking" (which starts on page 6.1-9).   It's also preceded by the same words you've quoted from your 14th Edition (although no reference to the 1964 AWS article).Judging by the larger context I agree with you that it's not about pipe welding.  Rather I think it's talking about a 2G (horizontal) groove weld in plate.  Based on all that was said in the preceding paragraphs under that heading ( "Observations on Factors Contributing to Cracking")  I think what they're trying to get at with saying "3-o'clock" (2G) groove welds being more sensitive to cracking than flat position groove welds has to do with the fact that running a horizontal groove weld usually requires that you run at a lower heat and use more passes (both being factors that can contribute to cracking) to make than you would need to make a similar sized groove weld in the flat position.   Essentially you can use more heat and fewer passes to make a groove weld in the flat position (which is better for avoiding factors that can contribute to cracking)  than you can use for making a horizontal groove weld.   And that basically has to do with the fact that you just can't put down as large of beads when welding horizontally as you can when welding flat due to the effect gravity has on a molten weld puddle.Last edited by HT2-4956; 02-22-2015 at 10:25 AM.
Reply:@ HT2 -  your interpretation makes complete sense.  Thanks for the input."Discovery is to see what everybody else has seen, and to think what nobody else has thought" - Albert Szent-Gyorgyi