EN1591 Flange Design - Visual Vessel Design (VVD) or alternative? 1

[LarryDavid]

Hi All,

I have noticed a few people out there are using VVD by Ohmtech. Could someone please let me know if the software has the capability to solve (determine) the flange thickness for a non-standard flange design? Or if there is any other alternative software that can do this?

I am designing a number of non-standard flanges to EN1591, i.e using the EN1092-1 standard dimensions for the OD, bolt PCD etc, but increasing the flange thickness.

Currently I have written a Mathcad calculation to EN1591, however the required flange thickness is something which I can only solve using trial and error. (I'm not sure how to do this using automatic iterations).

I have used trials for a couple of software packages such as Pipemill, LV-soft, and they all seem to work in the same way.

Any help will be much appreciated.
Cheers

Damian

 

[hartsa]

We are using VVD and it can calculate flanges according to EN1591 or EN13445-3 annex G. It also calculates flanges according to EN13445-3 clause 11 (Taylor-Forge Method).

So you can calc non standard flanges with VVD. But I think that it does the same as your MathCad. You give some thickness to flange and the program tells you that is the flange thick enough. It cannot solve the minimum thickness automatic.

But why are you increasing the flange thickness? I think that the flanges in new edition of EN1092-1 are calculated with EN1591. And if you select the flange from the category that your application requires (PN and temp) they should be ok without calculations?

regards
Harri

 

[C2it]

The programs listed do essentially the same calculation. There are too many variables to expect software to optimise a flange design. Just a few runs, changing the parameter you want to minimise should give you the answer you need.

I am surprised that you can use a MathCad routine .. is it an iterating procedure ? Pipemill can do over 3000 iterations in solving a soft gasket to EN1591.

 

[LarryDavid]

I am increasing the thickness because I am designing flanges which are outside of the given pressure ratings in 1092.
For example a PN40 DN1200 flange. The table in 1092 for PN40 only goes up to DN600.

Yes iterations are required in my Mathcad calculation (it iterates to find FG0 and bGe), however I find it reaches the required precision after only 6 or so iterations.

Thanks for the comments.