UA 457 then CA 3174 at O'Hare
Los Angeles → Chicago → Guangzhou
Timetable, Chicago time
18:56UA 457 from Los Angeles at the gate
13:40CA 3174 to Guangzhou leaves the gate
18 h 44 apart on the timetable, overnight
CA 3174 leaves 18 h 44 after UA 457 arrives on the timetable: more than half a day, so not a connection we count.