AS 579 then CA 3174 at O'Hare
Seattle (SEA) → Chicago → Guangzhou
Timetable, Chicago time
18:20AS 579 from Seattle (SEA) at the gate
13:40CA 3174 to Guangzhou leaves the gate
19 h 20 apart on the timetable, overnight
CA 3174 leaves 19 h 20 after AS 579 arrives on the timetable: more than half a day, so not a connection we count.