Method for detecting welding cracks of inclined Y-shaped groove

Abstract

The invention relates to a method for detecting welding cracks of an inclined Y-shaped groove. The method comprises the following steps: (1) selecting an appropriate welding material; (2) optimizing processing morphology of the groove; (3) performing preweld cleaning; (4) test piece splicing; (5) welding and restraining the weld joint; (6) preheating a testing weld before welding; (7) welding thetesting weld; (8) post-weld treatment; (9) performing weld coloring; and (10) assessment of the crack. The step (2) comprises the following sub-step: preparing samples 1 and 2, wherein the assembly structure of the sample 1 is a wedge surface which is in a longitudinal symmetry manner and mutually presents a tip top, and the assembly structure of the sample 2 is as follows: the two sides are in the shape of a wedge surface which is in a longitudinal symmetry manner and mutually presents a tip top, the middle is a slope extending up and down, the relatively upper wedge surface of the slope wholly sinks in parallel, and the sinking depth is consistent with the standard required post-weld inclined Y root gap. In addition, the method disclosed by the invention directly adopts a coloring snap or bend breaking method, and the surface crack rate, root crack rate and section crack rate can be intuitively measured.

Description

Technical field [0001] The invention belongs to the field of welding cracks, and is suitable for (but not limited to) carbon steel and low-alloy steel electrode arc welding and gas shielded welding joint cold crack sensitivity inspection and research. Background technique [0002] National standard GB / T32260.2-2015 "Destructive test of welds in metallic materials. Cold crack test of welded parts. Arc welding method Part 2: Self-restraint test" and ship industry standard CB / T4364-2013 "Slanted Y groove Welding crack test methods "standards all have strict requirements on the oblique Y root gap after welding; among them, the national standard GB / T32260.2-2015 "Destructive test of metal material welds. Cold crack test of weldment arc welding method part 2 :Self-restraint test” requires the post-weld oblique Y root gap 2.0±0.2mm; the ship industry standard CB / T4364-2013 “oblique Y groove welding crack test method” standard requirements are more stringent, electrode arc welding: 2.0±0...

AI Technical Summary

Problems solved by technology

[0004] The technical problem to be solved by the present invention is to provide a reliable method for inspecting oblique Y-shaped groove welding cracks in view of the above-mentioned prior art, improve the deficiency of the existing national standard inspection, and reduce the risk of excessive gap size at the root of the groove by changing the groove form. Greatly improve the test efficiency and test success rate; reduce the oblique Y root gap error caused by artificial factors; help to ensure that welders of different levels can weld the oblique Y root gap required by the standard

Images