The DEEP DRILLER is loaded as shown in the Sample Load Form #1 (Transit). What is the new metacentric height corrected for longitudinal free surface effects if the entire contents of salt water ballast 1anks 1P and 1S are discharged? (Use KML = 348.58)
• Transverse metacentric height (GM) and how it is obtained from the sample load form (KG, KM, GM) • Effect of discharging ballast from low side tanks on KG and GM • How to apply longitudinal free surface correction (FSC) using the given KML = 348.58
• From the original transit condition on Sample Load Form #1, what is the GM before you change anything? How do you read or calculate it from KM and KG? • When you discharge the contents of salt water ballast tanks 1P and 1S, does the ship’s KG go up or down? By how much, based on the weight and VCG (vertical center of gravity) of those tanks? • How is the free surface correction related to KML, displacement, and the free surface moment of the slack tanks? After discharging 1P and 1S, what happens to the longitudinal free surface correction term?
• Be sure you are using the correct initial GM (or KG and KM) from the exact transit condition on Sample Load Form #1, not a different condition on another form. • Confirm whether tanks 1P and 1S are full or slack before discharge; this affects whether they contribute a free surface moment in the initial condition. • When correcting for free surface, make sure you are using the correct formula with KML = 348.58, the vessel’s displacement, and the total free surface moment of all remaining slack tanks after the ballast is discharged.
No comments yet
Be the first to share your thoughts!