Welding crack test method for oblique y-groove test method for guaranteeing weld gap

Abstract

The invention discloses a test weld gap clearance ensuring method in an oblique Y-groove weld cracking test method and a test plate, belonging to the technical field of welding; the method mainly comprises the following steps: designing a groove type which is provided with a groove opening and is convenient to control a welding shrinkage allowance of restriction weld gaps: a difference between the improved test plate and the test plate in national standard BG4675.1 is that an entire groove surface of the test weld gap, relative to wedge surfaces of the two adjacent restriction weld gaps, sinks parallel to the original wedge surface to form the groove opening; the horizontal sunk depth of the groove opening is controlled between 2.5mm and 3.5mm and the best value is controlled at 3.15mm to 3.25mm; aiming at the restriction weld gaps, formulating a reasonable welding process and welding process control requirements: a welding method of manual tungsten argon arc welding and shielded metal arc welding is adopted. The method and the test plate disclosed by the invention can achieve the purpose of quickly and accurately controlling a test weld gap root groove clearance in the oblique Y-groove weld cracking test method; meanwhile, roots of the restriction weld gaps can be ensured to be welded thoroughly and the whole test process can be enabled to be carried out smoothly.

Description

technical field [0001] The invention belongs to the field of welding technology, and is mainly used for ensuring the root clearance of test welds and the penetration of restrained welds when evaluating the cold crack and reheat crack sensitivity of steel materials and welding materials by adopting the oblique Y-groove welding crack test method. Background technique [0002] The oblique Y-shaped groove welding crack test is a test method used to evaluate the welding crack sensitivity of steel and welding materials. The groove form and size of the test plate for the test are shown in the attached Figure 1-3 , The test process and requirements are detailed in the standard GB4675.1-84. The key to this test method is that when the restraint weld is welded, while ensuring the penetration of the root, after the restraint weld is welded, the root gap of the test weld groove is guaranteed to be 2.0±0.2mm before the test weld can be welded. , to ensure the accuracy of the test result...

AI Technical Summary

Problems solved by technology

In order to ensure the penetration of the root of the restraint weld and ensure that the gap at the root of the groove is guaranteed to be 2.0±0.2mm before welding the test weld, there are two common methods: one is to weld the restraint weld at the root of the test weld ( figure 2 A backing plate of about 2mm is pre-set at the slope in the A-A view of A-A). After the restraint weld is welded in this way, the restraint stress at the root of the test weld is very large, and the pre-set backing plate cannot be taken out, so it is generally not used; in addition One method is: when welding the constrained weld, the gap at the root of the test weld is guaranteed by reserving the root gap of the constrained weld and the welding shrinkage. However, due to the size of the welding shrinkage and the welding method, welding process The parameters and the welding process have a great relationship, and it is difficult to quantify. In addition, because the restraint weld is inconsistent with the test weld groove itself, and the test weld groove surface cannot be damaged when the restraint weld is root cleaned, the actual root clean The operation is difficult and the workload is also large

It can be seen that this traditional operation method has high requirements for the assembly and welding of restraint welds, and it is very difficult to implement, and it is difficult to ensure that the root gap of the test welds is 2.0±0.2mm, and the scrap rate of test plates is very high. This will not only increase the workload of test panel preparation, but also increase the test cost, and at the same time, affect the test efficiency and cycle

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