What is the difference between A36 and A105?
Thread Content
There is a petroleum refining integration project, and now it is necessary to prepare blind plates for pipeline pressure testing. The owner has provided a list of minimum thickness requirements for these temporary blind plates (calculated in accordance with ASME standards), but the thickness of some of these blind plates exceeds the minimum thickness required for blind flanges as specified in AMSE. The question is: 1) Theoretically, can temporary blind plates whose thickness exceeds the minimum thickness required by AMSE be replaced with regular blind plates? If a substitute is possible, should A105 or A36 be chosen as the material? 2) What are the differences between A36 and A105, and can they be used interchangeably? I need the advice of experts; it’s urgent. Thank you!
They are all types of carbon steel; A36 has properties similar to China’s Q235B, while A105 is comparable to 20# steel. Q235B is slightly inferior to 20#, but given that the pressure levels are not high, I think it’s acceptable to use Q235B instead
A plan must be developed for the pressure testing! The technical lead must approve it!
Thank you! The maximum pressure is 368 kilograms.
This post was last edited by Wugang Panglong2014 on June 21, 2019, at 09:03. A36 is the standard for rolled steel plates, while A105 is the standard for forged steel. Determining which domestic grades can be interchanged with these requires a process evaluation. For example, A36 has different composition and mechanical properties compared to Q235B in China; the upper limit for carbon content in A36 is higher than that in Q235B, while the upper limit for manganese content is higher in Q235B than in A36 ； Mechanically, as the thickness of Q235B increases, its mechanical properties gradually decline, whereas the mechanical properties of A36 do not change with thickness; its yield strength remains at 260 Mpa. Furthermore, if there are no additional requirements, A36 is not subject to cold bending and impact tests, whereas Q235B must undergo such tests upon leaving the factory. American standards and Chinese standards belong to different standard systems; any substitution of specific materials requires an objective and thorough evaluation. Wugang Panglong 13137747779