PSI - Issue 60

Rohan Nair et al. / Procedia Structural Integrity 60 (2024) 93–114 Rohan Nair / StructuralIntegrity Procedia 00 (2023) 000–000

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4

Fig. 4: Sectional view image of IC-ring

2.1.

Manufacturing of Test Article: Major Processes involved in realization of Water Tank Test Article are shell forming, heat treatment, Ring machining and welding [5]. Shell forming: There are 2 toroidal shell segments in the test article. Each toroidal shell segment is made of two half shells which are formed from 2mm thick AA6061 sheet in T0 temper condition. The half toroidal shells are formed using punch and die in a 250T hydraulic press and the profile is checked by a template. The thickness was mapped at 63 locations for each of the formed half shells and was found to be in the range of 1.78-2.03 mm which is well within the design thickness of minimum 1.5mm. The formed shells were heat treated to T6 i.e. by solutionizing and ageing as per AMS 2772[6], standard. Following are the details of heat treatment followed on formed shells and baffles.  Solutionizing : 535 + 10 o C for 35 minutes, followed by water quenching.  Ageing : 160 + 5 o C, 18 hrs followed by air cooling. The test coupons kept along with the heat treatment of the job for evaluating the tensile properties of the material. Fig. 5 describes the manufacturing sequence of shell. 2.1.1.

2mm sheet (T0 temper)

Solution heat Treatment

Artifical Ageing

Forming

T6 Temper

Fig. 5: Fabrication flow chart for water tank shells

2.1.2.

IC ring, flange, adaptor I, II & III: