Submerged Arc Welded (SAW) Pipes - GE Inspection Technologies - #1

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GE Inspection Technologies Ultrasonics Krautkramer Testing Machines Submerged Arc Welded (SAW) Pipes Submerged arc, longitudinally welded tubes: testing weld seams, heat affected zones and tube ends The facts are somewhat different with submerged arc, spirally welded tubes: The complete test of the parent material (plate testing) should be made in the production process: The test in the pipe wall is possible but involves mores cost. Therefore all that remains for the finishing shop to do is to test the weld seam, the parent material in the heat affected zone and the tube ends. Frequently such longitudinally welded tubes have thick walls for which further testing is required: on one hand, additonal levels for longitudinal and transverse defects can be included, on the other hand testing can be extended to the socalled tan-dem technique. The tandem method separately monitors the center area of the weld in order to detect defects which are vertical to the surface. Angle-beam probes can be used which test for transverse flaws in the heat affected zone. The orientation of these defects is perpendicular from the weld seam into the HAZ. Testing weld seams and parent material with complexed systems: SNUP With this testing machine the probes are positioned from above in pairs. Probe guiding devices with vertical and horizontal movement units enable automated tracking of the test system. The complete mechanics must be mounted on a column support with boom or onto a portal. L1 Tandem Q1 D1 Flaw L2 Q2 Add. from approx. 16 mm Add. from approx. 30 mm wall thickness Q3 Q4 Up to approx. 16 mm Q1 Q2 Tandem test Weld seam inspection on SA-longitudinally welded pipes