MAX VCG IN Autohydro

[dmetawie]

Dear Gents,
While calculating MAXVCG for a drilling rig using Autohydro's MAXVCG Toturial example I get a high deviation from the one previously calculated in the Ops manual, can you please help?

[Paul Kotzebue]

I think there is a problem with the AutoHydro MAXVCG command.

I made a stability submittal to ABS with a MAXVCG curve generated by AutoHydro. I included my AutoHydro RUN file with the submittal. When ABS ran my RUN file using GHS, they got different results. I had to re-submit my calculations using GHS to produce the MAXVCG curve, which matched what ABS was getting.

ABS had the same GF file I was using. The AutoHydro MAXVCG's were higher then the GHS MAXVCG's.

I tried running righting arm curves with the VCG set at MAXVCG in both AutoHydro and GHS. GHS hit the stability criteria limits as expected, but AutoHydro did not. Because the AutoHydro righting arm curve matched the GHS righting arm curve, I suspect the problem is in the AutoHydro MAXVCG command.

I suggest you calculate MAXVCG with softeare other than AutoHydro and see if it matches the ops manual.

[bill_boggia]

Can anyone recommend a method of calculating MAX VCG in free ship or using annother open source software that will accept export from freeship ?

(For the multispar structure I have in mind the GHS translator from freeship does not facilitate a correct import)

Thanks

Bill :-)