Complex sentence: Such a splitting had happened on several T2 tankers, and many were discovered during inspections to have hairline or larger fractures within the keel and on major frames; companies who owned T2 tankers were ordered to pay attention to the keel when inspecting.
Split into simpler sentences: Such a splitting had happened on several T2 tankers, and many were discovered during inspections to have hairline or larger fractures within the keel and on major frames. Companies who owned T2 tankers were ordered to pay attention to the keel when inspecting.