Hi, Richard...

I'm a new COADE Tank software user.

Now I'm designing a CRT Tank (mat'l A283-C) and need your advice.

DESIGN DATA:
- ID = 17 m
- Height = 16 m
- Design Pressure = Full Liquid+100 mm H2O
- Design Ext Pressure = 50 mm H2O
- Design Temp. = 70 C degree
- Design Liquid Level = 16 m
- Liquid SG = 1
- Corrosion Allowance = 1.5 mm
- Site Class E
- Sp = 0.3
- Ss = 0.75
- S1 = 0.375
- SDs = 0.6
- I = 1.25
- Rwi = 4
- Wind velosity = 25 m/s

After I calculate using COADE Tank, I found this tank is un-anchored, J = 1.0554.
When I checked the calculation output, the value Ai = 0.066964, it means this Ai is got from API equation E.4.6.1-3.

Could you kindly advise wether we can use this Ai value, even when we manually check using API equation E.4.6.1-1, we will get higher Ai value (0.1875)?

Thank you for attention.

Regards,
Amar F