Four Methods Of Destructive Detection Of Steel Structure Welding

① Tensile test.

The tensile test can not only measure the strength and plasticity of the weld. At the same time, defects at the fracture can also be found. It can also verify whether the welding materials and construction process used are correct.

② Bending test

The bending test is used to check the plasticity of welded joints, which can reflect the plastic difference of each area of the joint. Expose welding defects and check the bonding quality of fusion line.

③ Impact test

The impact test is used to assess the impact toughness and notch sensitivity of weld residues and welded joints.

④ Hardness test

The hardness test can measure the hardness of weld and heat affected zone. The strength of the material can also be estimated indirectly. It is used to compare the performance difference of each zone of welded joint and the hardening tendency of heat affected zone.

(2) Broken section inspection

To ensure that the weld is disconnected at the profile. A groove can be carved on the weld surface along the weld direction in advance. The groove depth is about 1/3 of the thickness. Then use a tensile machine or hammer to break the test piece. On the fracture surface, various welding defects visible to the naked eye, such as pores, slag inclusion, incomplete penetration and cracks, can be found; It can also judge whether the fracture is ductile failure or brittle failure.

The weld fracture section inspection has the advantages of simplicity, rapidity, ease of operation and no need for special instruments and equipment. It can be widely used in production and installation sites.

(3) การตรวจสอบการขุดเจาะการตรวจสอบการขุดเจาะในท้องถิ่นจะต้องดําเนินการสําหรับรอยเชื่อม ข้อบกพร่องเช่นความพรุนการรวมตะกรันการเจาะที่ไม่สมบูรณ์และการแตกร้าวในการเชื่อมสามารถตรวจสอบได้

(4) Metallographic examination Welding metallographic examination is mainly to study and observe the changes of metallographic structure and micro defects caused by welding heat process. Metallographic examination can be divided into macro metallographic examination and micro metallographic examination.

The metallographic inspection method is to cut the sample on the welding test plate (workpiece), and then grind, polish and etch it. Then observe under the metallographic microscope. When necessary, typical metallographic structures can be taken into metallographic photos. For analysis and research.