AA 2642 then CA 3174 at O'Hare
San Francisco → Chicago → Guangzhou
Timetable, Chicago time
21:50AA 2642 from San Francisco at the gate
13:40CA 3174 to Guangzhou leaves the gate
15 h 50 apart on the timetable, overnight
CA 3174 leaves 15 h 50 after AA 2642 arrives on the timetable: more than half a day, so not a connection we count.