Effective throat for PJP D1.6 or D1.1

Date 06-06-2008 21:41

I'll apologize in advance people must be getting tired of me asking a lot of welding design code questions.
this pertains to effective throat in D1.6 in section 2.4.1.2(2) In PJP welds effect weld size shall be determined in 3.15... and in 3.17. These are for joints with bevels. Is there a methodology for determining effective throat in a single pass square groove weld with no reinforcement? B-P1a I believe is the relevant joint in it, it lists weld size as 3T/4 is that my effective weld throat? which I can then use to calculate design strength based on table 2.1?
I assume D1.1 table 3.4 would come into play specifying the maximum throat is 1/16th for that joint.
How about B-P1b a square groove weld from both sides with no backgouging? how would I calculate effective throat then?
am I overcomplicating and confusing myself. Those are the two most common Groove weld joint details I see and I was tasked with calculating the design strength, I've been working my way along until I realized I didn't know how to determine the effective throat on PJP groove welds that have no bevel.

thanks in advance
Welding engineering Intern Metarinka

By jwright650 (*****)

Date 06-17-2008 12:43

I was going to take a shot at this question, but I don't have a current copy of D1.6 and fear the paragraphs could have been revised in later editions. Basically to be brief, for the PJP joints you would subtract an 1/8" from your depth of bevel to figure your weld size. Having said that, you still need to mock up the joint and weld it, then cut and etch to make sure that you are indeed getting what you called out for in regards to your weld size(IOW, verify the depth of penetration).

If you are using a prequalified joint detail like the B-P1a and you follow the tolerances, you will most likely get an acceptable weld due to using the time tested and proven prequalified joint details. Enough of these joints have been welded and tested over the years that AWS feels confident enough to publish the prequalifieds for you to use without asking you to perform all of the qualification testing yourself.