FEA of Ductile Cast Iron vessels

[gurmeet2003]

I work for a compressor manufacturing company. Currently we use ASME Section VIII to design the compressor cylinders. By designing I mean figuring out the thickness of walls and deciding reinforcement around holes. Strictly speaking the code is not applicable to compressor cylinders. However we have used it successfully for a number of years. In order to validate new design we carry out a burst test on one piece and use the code specified factor to arrive at MAWP from the burst pressure.

Now we are trying to use FEA for design. The pressure ratings are about 3000 psi or lower. My question is as follows:

1. Should we try to use Non linear FEA to predict the burst pressure and continue to use burst testing for validation?
2. or Can we use FEA based on the service loads (pressure, bolt loads etc.)? If we use FEA only then how is FEA validated for pressure vessels? Does code or any similar publications provide guidelines on this?

I would appreciate any information on above point.

Thanks,

Gurmeet

 

[metengr]

Based on your post, I would stick to what works best for you - validate any design change by using a hydrostatic test.

 

[unclesyd]

You got to leave some meat in walls where we can work on them.
The last thing anyone using a compressor wants is just enough wall thickness, especially CI.