# Pls help- thin-walled pressure vessel

pls help-- thin-walled pressure vessel

Hi, all. I have done an experiment of “thin-walled pressure vessel”. The vessel: length 200mm, outside radius 526mm, inner radius 47.6mm. There were two rectangle rosettes gauge in the vessel surface. Based on the experiment data (100 psi), the actual principle stresses of the two gauges are calculated: 1) 72 Gpa (hoop) and 37 Gpa (axial). 2) 66 Gpa (hoop) and 32 Gpa (axial). And the theoretical principles are: 62 Gpa (hoop) and 31 Gpa (axial).

I am wondering why the stresses of gauge one are mush bigger than the gauge 2. Can somebody tell me why?

Thank you very much!