DL 3913 then DL 281 at Seattle
Portland (Oregon) → Seattle → Shanghai
Timetable, Seattle time
20:50DL 3913 from Portland (Oregon) at the gate
14:40DL 281 to Shanghai leaves the gate
17 h 50 apart on the timetable, overnight
DL 281 leaves 17 h 50 after DL 3913 arrives on the timetable: more than half a day, so not a connection we count.