ASTM_F_1321_-_14.pdf

Designation:F132114An American National StandardStandard Guide forConducting a Stability Test(Lightweight Survey andInclining Experiment)to Determine the Light ShipDisplacement and Centers of Gravity of a Vessel1This standard is issued under the fixed designation F1321;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the U.S.Department of Defense.INTRODUCTIONThis guide provides the marine industry with a basic understanding of the various aspects of astability test.It contains procedures for conducting a stability test to ensure that valid results areobtained with maximum precision at a minimal cost to owners,shipyards,and the government.Thisguide is not intended to instruct a person in the actual calculation of the light ship displacement andcenters of gravity,but rather to be a guide to the necessary procedures to be followed to gather accuratedata for use in the calculation of the light ship characteristics.Acomplete understanding of the correctprocedures used to perform a stability test is imperative to ensure that the test is conducted properlyand so that results can be examined for accuracy as the inclining experiment is conducted.It isrecommended that these procedures be used on all vessels and marine craft.1.Scope1.1 This guide covers the determination of a vessels lightship characteristics.In this standard,a vessel is a traditionalhull-formed vessel.The stability test can be considered to betwo separate tasks;the lightweight survey and the incliningexperiment.The stability test is required for most vessels upontheir completion and after major conversions.It is normallyconducted inshore in calm weather conditions and usuallyrequires the vessel be taken out of service to prepare for andconduct the stability test.The three light ship characteristicsdetermined from the stability test for conventional(symmetri-cal)ships are displacement(“displ”),longitudinal center ofgravity(“LCG”),and the vertical center of gravity(“KG”).Thetransverse center of gravity(“TCG”)may also be determinedfor mobile offshore drilling units(MODUs)and other vesselswhich are asymmetrical about the centerline or whose internalarrangement or outfitting is such that an inherent list maydevelop from off-center weight.Because of their nature,otherspecial considerations not specifically addressed in this guidemay be necessary for some MODUs.This standard is notapplicable to vessels such as a tension-leg platforms,semi-submersibles,rigid hull inflatable boats,and so on.1.2 The limitations of 1%trim or 4%heel and so on applyif one is using the traditional pre-defined hydrostatic charac-teristics.This is due to the drastic change of waterplane area.Ifone is calculating hydrostatic characteristics at each move,such as utilizing a computer program,then the limitations arenot applicable.1.3 The values stated in inch-pound units are to be regardedas standard.No other units of measurement are included in thisstandard.1.4 This standard does not purport to address the safetyconcerns,if any,associated with its use.It is the responsibilityof the user of this standard to establish appropriate safety andhealth practices and determine the applicability of regulatorylimitations prior to use.2.Referenced Documents2.1 ASTM Standards:E100 Specification for ASTM Hydrometers3.Terminology3.1 Definitions:3.1.1 inclining experimentinvolves moving a series ofweights,in the transverse direction,and then measuring theresulting change in the equilibrium heel angle of the vessel.Byusing this information and applying basic naval architectureprinciples,the vessels vertical center of gravity KG is deter-mined.1This guide is under the jurisdiction of ASTM Committee F25 on Ships andMarine Technology and is the direct responsibility of Subcommittee F25.01 onStructures.Current edition approved May 1,2014.Published May 2014.Originallyapproved in 1990.Last previous edition approved in 2013 as F1321 131.DOI:10.1520/F1321-14.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 3.1.2 Condition 1vessel in Condition 1 is a vessel com-plete in all respects,but without consumables,stores,cargo,crew and effects,and without any liquids on board exceptmachinery fluids,such as lubricants and hydraulics,are atoperating levels.Condition 1 is sometimes referred to as“operational light ship.”3.1.3 Condition 0vessel in Condition 0 is a vessel asinclined.3.1.4 lightweight surveythis task involves taking an auditof all items which must be added,deducted,or relocated on thevessel at the time of the stability test so that the observedcondition of the vessel can be adjusted to the light shipcondition.The weight,longitudinal,transverse,and vertic