CA 1236 then KE 852 at Beijing
Xi'an → Beijing → Seoul Incheon
Timetable, Beijing time
23:15CA 1236 from Xi'an at the gate
18:55KE 852 to Seoul Incheon leaves the gate
19 h 40 apart on the timetable, overnight
KE 852 leaves 19 h 40 after CA 1236 arrives on the timetable: more than half a day, so not a connection we count.