Interchange

In 1944, the ASME Code Committee recognized the waste involved in repetitively qualifying welding procedures. It was seen that the welding procedure, which is essentially a method of welding, would in no way be improved by being qualified time after time. Likewise, the transfer of a qualified welder from one employer to another if he could use the same welding procedure posed no threat to quality workmanship. At that time these ideas were incorporated in Section I in what is now PW-28.5, stating:

"To avoid duplication of qualification tests, it is recommended that procedures, welders, and welding operators qualified as required above be acceptable for any similar welding work using the same procedure."

Thus for over forty years interchange of procedures and welders has been authorized on boiler piping under Section I, and has been practiced with success.

B31.1 had previously added Paragraph 127.5.3. Provisions of 127.5.3 cover the same ideas as PW-28.5, but do so in a more specific manner. These provisions are:

127.5.3 Qualification Responsibility

(A) Procedures. Each employer shall be responsible for qualifying any welding procedure that he intends to have used by his organization. However, to avoid duplication of effort, and subject to the approval of the owner, welding procedures qualified by a technically competent group or agency may be used:

(A.1) if the group or agency qualifying the procedures meets all of the procedure qualification requirements of this Code;
(A.2) if the fabricator accepts the procedure thus qualified;

(A.3) if the user of the procedure has qualified at least one welder using the procedure qualification;

(A.4) if the user of the procedure assumes specific responsibility for the procedure qualification work done for him by signing the records required by Para. 127.6.

All four of the above conditions shall be met before a procedure thus qualified may be used.

(B) Welders and Welding Operators.

Each employer shall be responsible for qualifying all the welders and welding operators employed by him. However, to avoid duplication of effort, he may accept a welder or welding operator qualification made by a previous employer (subject to the approval of the owner or his agent) on piping using the same or an equivalent procedure wherein the essential variables are within the limits established in Section IX, ASME Boiler and Pressure Vessel Code.

Subsequently, other sections of B31 have adopted the language of 127.5.3, except for B31.3 which has a variation of the statement. Sections III, VIII, and XI of the ASME Boiler and Pressure Vessel Code have no provision for interchange.