Three hours. According to Baidu map, it takes three hours to transfer from Luoyang to Luanchuan 148.9 km by rail transit line 2. Specific route:

1. First walk 760m from Luoyang and arrive at Citizen's Home Station.

2. Secondly, take Rail Transit Line 2, pass three stops and arrive at Longmen high-speed railway station.

3. Then walk 430m to Longmen Station in Luoyang.

4. Finally, take the Luoyang-Luanchuan intercity express, pass 2 stops, and get off at Luanchuan County Station to reach Luanchuan.