Splice weld ?

Date 12-12-2009 06:29

Hello all,
After a bit of advice please.
Project specifications state that splice welds require 100% NDT (UT or RT)
We are working to AWS D1.1 and are fabricating trestle legs for overland conveyors.
As we cannot source 30" pipe here in Thailand we are rolling 5/8" plate to form 10" lengths of pipe.
Some of our legs are 65" long.
We are welding the longitudinal and circumferential welds with backing strips.
Will the circ welds be classed as splice welds and require 100% NDT or just as butt welds and therefore requiring 10% NDT ?
Any help greatly appreciated,
Regards,
Shane

By waccobird (****)

Date 12-12-2009 11:57

Shane Feder
That is a question for the Engineer.
I would have to say you are splicing rolled plate 10' long to make the 65' leg.
Just me and the information I have.
Good Luck
Marshall

By swnorris (****)

Date 12-12-2009 15:24

Shane,

Just curious. What grade of plate are you rolling? Does it at least match the yield and tensile properties of a manufactured pipe? Regardless, I would think that you'd have to submit the material grade and/or MTR, along with a splice detail to the EOR for approval.

By 803056

Date 12-14-2009 04:04 Edited 12-14-2009 04:07

I have to agree with Marshall, I would ask the engineer what his intent is. Columns can be spliced as well as beams. In each case I would expect "splice plates" to be used to sandwich the main member. Clearly that isn't the case as you describe it.

From AWS A3.0 Standard Terms and Definitions:

spliced butt joint. See spliced joint. See Figures 3(A)
and 3(B).
spliced joint. A joint in which an additional workpiece
spans the joint and is welded to each joint member.
See Figures 3(A) and 3(B). See also splice member.
splice member. The workpiece that spans the joint in a
spliced joint. See Figures 3(A) and (B).

The splice plates participate in transferring the loads from one member to the other. That wouldn't be the case with the backing bars you described.

Best regards - Al

a3.0-2001-SpliceSketch13-Dec-09.jpg (138k)

By jwright650 (*****)

Date 12-14-2009 12:53

Could it be that there is a slight mis-communication problem with the terminology "splice welds"?....could they possibly be trying to call out all "full pen welds" rather than "splice welds"? I would get a clarification on the terminology. Personally, If we were rolling plate into structural pipe sections and welding the seam in our shop....I would UT every inch of that section, but that is just what I would do, regardless of what the job spec stated. When I think of splice plates, I think of something similar to what Al posted a sketch of.

However, I have seen joints where we had pipe columns that were spliced with a piece of plate, top and bottom shafts were welded(full pen) to a piece of plate. The plate MUST be UT'd for lams before splicing.

Attachment: SketchesforUTreportsModel1.pdf (13k)