WELDING PROCEDURE QUALIFICATION AND WELDER’S QUALIFICATION
EN-287 (A.S.M.E SECTION IX) → Welders Qualification.
E.N- 288 → Procedure Qualification.
A.W.S – D -1.1 → Structural Welding of Steel.
A.W.S – D – 1.2 → Structural welding of Aluminum.
- Welding Variables are divided into two types:
- ESSENTIAL VARIABLE. ( Current, voltage & travel speed.)
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- NON-ESSENTIAL VARIABLE. ( Bevel angel, rootyface, rootgap.)
- Essential Variable effect the Mechanical Properties .
- Non-Essential Variables doesn’t effect Mechanical Properties no re-qualification is not required if changed.
- If Essential Variable is changed beyond specified limits, then Procedure Re-Qualification is required.
- Welder Qualification Certificate is valid for 2 Years.
- If welder is absent for more than 6 months then Re-Qualification of welder is required.
- The document written berfore writing W.P.S is Premilinary W.P.S.
- Toughness decreases with increase in heat input.
- If hardness increases then joint is prone to hydrogen cracking.
- Low heat input causes high hardness.
- Poorosity is caused due to use of damped electrode.
- Impact test isnot required for qualifying a welder.
STEPS TO WRITE APPROVED WPS:
- Preliminary welding procedure specification
- Welder follws the PWPS & weld the joint of given sample in presence of welding inspector & third party inspector.
- Then the sample is tested with NDT & D.T
- Welding inspector will write Procedure Qualification Record including details namely:
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- As run condition
- NDT result
- DT result
- Qualification range
- Then welding engineer will write an Approve WPS if all the results are satisfactory & in the range.
WELDERS QUALIFICATION:
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- Welding engineer will write WPS
- Welder follows it & makes a joint on sample given
- Sample is subjected to NDT & DT
- If results are satisfactory the welder is approved & certificate is issued which is valid for 2-years.
WELDING CODES AND STANDARDS
B.S.E.N – 970 → NDT of Fusion Welds (or) Visual Inspection.
E.N – 473 → Vision Test.
B.S.E.N – 287 →Welders Qualification.
B.S.E.N – 288 → Procedure Qualification.
B.S – 499 → Welding terms.
B.S.E.N – 499 → Covered Electrodes.
B.S – 639 → Covered electrodes.
B.S.E.N – 22553 → Welding Symbols.