I would like to ask, is the ASME weld impact temperature based on MDMT or based on the impact requirements of the base metal?
Thread Content
I would like to ask, is the ASME weld impact temperature based on MDMT or based on the impact requirements of the base metal?
Usually, it is considered based on the MDMT temperature.
What is the MDMT temperature? Please explain in detail.
According to MDMT MDMT=Minimum Design Metal Temperature. In addition, according to ASME specification requirements, if the impact can be exempted, there is no need to conduct impact testing according to UG-84.
The specific process is as follows. The user's technical conditions specify the minimum operating temperature of the equipment. Then the designer calculates the impact exemption of the component based on this minimum operating temperature and in accordance with the specifications. If a component cannot be exempted, then the raw material or impact test plate of the component needs to be impact tested at the minimum operating temperature. If the impact value is qualified, the temperature is the MDMT of the component.
Is the impact test on raw materials or welds?
It depends on whether the parts you need to impact are welded parts or non-welded parts. If the welded parts cannot be exempted from impact, then an impact test plate + a welding evaluation with impact are needed to support； If it is a non-welded part, the heat treatment state of the impact test piece must be consistent with the supply or use state of the component. ；