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Qualification of Welding Procedures and Welder for Aluminum

Welding procedure specification (WPS)

WPS shall be established in accordance with EN 288 part 2. Information to be stated in WPS in addition to requirement in EN 288-2 as follows:

  • Base material standard, alloy and temper
  • Max. time limit between cleaning and welding

Qualification of welding procedures

Welding procedures used for aluminium structures, shall be qualified in accordance with EN 288 part 4 and the additional requirements in this standard. For welds specified in Inspection Category D qualified welding procedures are not required.

The qualification is valid for the workshop performing the welding tests, and other workshops under the same technical and quality management. It may also be transferred to and used by a  subcontractor, provided the principles of EN 729 are implemented and documented.

Qualification of Welding Procedures and Welder for Aluminum Qualification of Welding Procedures and Welder for Aluminum Qualification of Welding Procedures and Welder for Aluminum

Welding procedure approval record (WPAR) – Range of approval

The WPAR is valid within the limitations specified in EN 288 part 4, with  addition of the following essential variables which require requalification:

  • a change in heat input of more than + 15% and – 20%. If an approval testing have been performed at both a high and a low heat input level (with all specified mechanical testing), then all intermediate heat inputs are also qualified
  • a change from extruded aluminium to wrought (rolled, forged) aluminium shall require a new qualification test
  • an alloy within Group 23 qualifies for other alloys within group 23 with lower SMYS, but not  higher
  • any change in arc characteristics
  • a change from single pass to multi pass
  • a change in groove angle beyond -5°/+20°

A qualification of fillet welds carried out on plate thickness equal to or greater than 20 mm, applies for all plate and throat thicknesses.

Examination of the test weld

Testing shall be performed in accordance with EN 288 – 4.

Bend testing shall be carried out in accordance with EN 288 – 4 using controlled bend test method (wrap around). Bending angle shall be 180° using a mandrel with diameter according to table 3 in EN 288 – 4 (minimum diameter of the mandrel shall be 60 mm for material group 21 and 22a and 70 mm for material group 22b and 23).

The micro examination shall be in accordance with EN 288 – 4. The specimen shall be examined at minimum 20x magnification and shall be free from microcracks.

Welder and welding operators qualifications

The welders, welding operators and tack welders shall be qualified in accordance with EN 287, prEN 1418 or equivalent. For tack welders, an internal test may be used.

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