How to determine whether a material can be used in low-temperature conditions
Thread Content
For example, a material works fine at room temperature, but how can we determine whether it can be used at lower temperatures, and how is the impact energy determined? For example, A105: can it be used in an environment at -30 degrees? If so, what is the lowest temperature it can withstand? How to determine impact energy
Generally, materials have specified temperature ranges for use; it is recommended to consult Part 2 of GB150-2011, titled \"Materials\", which contains information regarding the temperature limits for using these materials
By referring to the relevant material standards and container design specifications, the drop-weight test is used to determine the ductile-brittle transition temperature of the material, while the impact test is used to assess the ductility of the material at its operating temperature
If ASME design and ASME materials are used, it seems there are no standards similar to those in China; the material A105 is mentioned. Can it be used at -30 degrees? Is a shock test required, and what should be the appropriate shock energy?
Page 7 of the tolerance specifications specifies the lower limit for impact energy; furthermore, after the allowable stress tables for each type of material in 150.2, there is a lower limit for temperature. According to regulatory requirements, foreign grades need to be submitted to the general administration for evaluation; it’s not that simple. Of course, since the owner wants to sell it abroad and is not following the usual routes, it is necessary to check the minimum temperature and impact energy requirements according to American material standards.
Step 1: When designing according to ASME standards, set MDMT to -30 degrees and then proceed with the calculations. As for SA105 material, it can be used for various components – it can serve as pipe flanges or as forged pipe fittings. Step 2: Check whether each component in the calculation sheet has been subjected to impact, as indicated by a table; then the designer makes judgments and adjustments. 3. For the impact energy of the material used for impact testing, it is determined according to the customer’s requirements if any (usually 27 joules); otherwise, it is selected based on Table UG84. Adjusting MDMT is a technical task that requires systematic learning*.
Another question: based on your experience, can the SA-105 be used in an environment at -30 degrees Celsius with a pressure of 22 MPa, for use as flanges and plugs?