Regarding the value of the impact temperature for welded joints
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:) For a design temperature of -45°C. The material is 09MnNiDR, and the low-temperature impact test temperature for the sheet metal is -70°C. So what is an appropriate low-temperature impact test temperature for the welded joint? What is an appropriate value for the impact energy?
Your low-temperature shock temperature should be -70 degrees. The impact energy should be the standard stress value at the corresponding temperature.
The low-temperature impact test temperature for welded joints is less than or equal to -45°C, with a minimum average impact energy of 18 J. See GB150 Appendix C, C2.1.7
From the perspective of understanding GB150, the low-temperature impact test temperature for welded joints is set to the same value as that for the sheet metal. However, in actual manufacturing processes, due to various factors involved in the production of welded joints, their toughness at low temperatures is significantly reduced. If the low-temperature impact test temperature for welded joints is set too low (i.e., at a level similar to that used for sheet metal), it is possible that the welded joints meet the requirements regarding low-temperature impact strength at the design temperature, but fail to meet those requirements during testing. On the other hand, is it feasible to set the low-temperature impact test temperature for welded joints to a higher level compared to that for sheet metal? And by how much should it be increased?
The low-temperature impact test temperature for welded joints is less than or equal to -45°C, with a minimum average impact energy of 21 J (this value has been increased per the amendment). See GB150 Appendix C, C2.1.7
W706Ni can be used as the welding material; at -70°C, the impact value should be no less than 27 J.
Has the original poster solved this problem?
I think it’s fine to conduct the tests at the design temperature; I’m not sure if that’s correct
Impact tests are conducted at -70 degrees, and the impact energy shall be no less than 20 J in accordance with GB150. According to GB3531, it should be no less than 47 J; I’m not sure if that’s correct. Please have an expert assess it