D1.6,Procedure Base Metal Help?

Date 11-25-2002 16:42

mhs:
Read note 1 of Table 3.2; "The correct Base Metal Group for a given base metal depends upon the ASTM specification to which it was purchased."

It would depend on the materials form and specification when generating the WPS. You would only qualify the material tested or listed in the WPS. Stainless is not like carbon steel where the code permits all within the group and below to be qualified. The D1.1:2002, Table 4.8 denotes qualification of base metal group combinations. There is no table like this in the D1.6. Also refer to 1.2.1 of D1.6.

Your WPS would qualify a specific base metal(s) & filler metal(s) combination and all within that group only.

By mhslfab (*)

Date 11-25-2002 17:57

Thank you for your response but after carefull review of your reply, I am not sure I agree with your interpretation and have added the following arguments. Does anybody else have an oppinion?
If D1.6 does not allow grouping than why does table 4.1 specify a change in base matel group as an essential variable? Maybe it should specify any change in base metal comsposition as an essential variable.
Section 4.2.1 (D1.6-99 I not have the 2002 yet) states any change to the vairables set forth in Table4.1 shall be considered essential changes and shall require the qualification of a new WPS.
Would it be possible to use a WPS created for 304L to 304L(Group A), to weld 316L to 316L(Group A)? All variables remain the same even the A number. The base metal has changed, but it is still within the same group.

By jwright650 (*****)

Date 11-25-2002 19:24

Do you have a WPS that was Qualified or Prequalified?

I believe that you need to look on your mill test reports for the ASTM Specification for the material you purchased and match it to Base Metal Group in Table 3.2 and filler metal in Table 3.3 to use a prequalified WPS.

It appears that you can join any group A material(3.2) with another group A material(3.2) and use filler metal from group A(3.3) and be considered prequalified. Join a group B material(3.2) to a group A material(3.2) you must use the filler metal(3.3) that corresponds to the lower strength of the two base metals to be considered prequalified.

"I think" you are OK as long as you match the filler metal correctly to the base metals, to be prequalified.

I too am looking at an old issue of D1.6.
John Wright

By DGXL

Date 11-25-2002 20:08

mhs:
I think you misunderstood my response.

I stated all within the group are qualified only.

Base metal composition is not the criteria for qualification (or re-qualification), I believe it is the weld metal deposit and ferrite content that determines this essential variable.

Your example of 304L/316L would qualifiy all within that group. If you qualified a Group B, it would only qualify all materials falling within that group. Not Groups B and A inclusive.

The 99' revision is the only revision of this code at the present time.

By jwright650 (*****)

Date 11-25-2002 20:16

So, my 99 isn't old after all!
John Wright

By mhslfab (*)

Date 11-25-2002 20:34

Thank You all for your replies.
This material has a ASTM 240 designation, which qualifies it for both group A & B. It seems funny that I can take the exact same material
(lets say 304L) and devalope a group A procedure, then take the exact same material drop the L because it is dual certified and create a group B weld procedure and nothing has changed. You would think one could develope one procedure (304/304L with a 308/308L filler) and qualify for both groups.
Oh! sorry about the D1.6 edition issue.

Thanks Again
Malcolm Hart

By jwright650 (*****)

Date 11-26-2002 14:00

Structural Steel has dual grades as well. ASTM 572 Grade 50 and ASTM A992 are now being produced as dual grade materials.
(A992/572 grade 50)All on the same label from the mill.
John Wright