These tanks serve the double purpose of enabling the ship to carry a part cargo of liquid in bulk and of improving her seaworthiness when in ballast or lightly loaded.
Ezi tanki zinceda uphindo lwendawo evumela inqanawa ithwale indawo yemithwalo yemithetho yamanzi kwisambuku kunye nokuphucula kolwandle xa lunezinto ezinzima ezilayishelwa inqanawa ngokobulula bemithwalo.