Trestala
Mechanical
- Feb 15, 2015
- 133
Hello, I have an excel calculation sheet that calculates the required thickness under external pressure of a pressure vessel using ASME BPVC Div. 1, UG-28(c).
The calculation method is that you have to assume first a thickness to get some parameters in the Code based on the diameter-to-thickness ratio and length-to-outside diameter ratio to ultimately get the maximum allowable external pressure (MAEWP). This MAEWP can just be compare that value to the design external pressure (e.g. FV or -15psi.g). The design external pressure can be divided by the MAEWP to see if it is less than unity 1.0 so it passes the calculation.
So, I have a cell where I place my assumed initial thickness (e.g. cell A1) which then calculates the MAEWP (placed in other parts of the Sheet), then another cell (e.g. cell A2) where it shows the ratio between Design External Pressure and MAEWP.
I want to automatically increment the value in cell A1 (loop in VBA?), for example increments of 0.01mm starting from a minimum thickness (e.g. 3mm), until the ratio in A2 reaches close to 100% but would not exceed 100%. There would be times that A2 would be in error since there is range of Do/t and L/Do that is outside the Code tables.
Can anyone point me in the right direction on how I can go about this?
The calculation method is that you have to assume first a thickness to get some parameters in the Code based on the diameter-to-thickness ratio and length-to-outside diameter ratio to ultimately get the maximum allowable external pressure (MAEWP). This MAEWP can just be compare that value to the design external pressure (e.g. FV or -15psi.g). The design external pressure can be divided by the MAEWP to see if it is less than unity 1.0 so it passes the calculation.
So, I have a cell where I place my assumed initial thickness (e.g. cell A1) which then calculates the MAEWP (placed in other parts of the Sheet), then another cell (e.g. cell A2) where it shows the ratio between Design External Pressure and MAEWP.
I want to automatically increment the value in cell A1 (loop in VBA?), for example increments of 0.01mm starting from a minimum thickness (e.g. 3mm), until the ratio in A2 reaches close to 100% but would not exceed 100%. There would be times that A2 would be in error since there is range of Do/t and L/Do that is outside the Code tables.
Can anyone point me in the right direction on how I can go about this?