Taking domestic flight after the international flight at Beijing Capital Airport

I have booked my flight from Chicago to BJ operated by United Airlines. The flight will reach at 3:15PM. I have also booked a flight from BJ to Yantai from Air China which departs at 6:40. Since both the flights are booked separately I have to take the boarding pass once I land at PEK, is this time sufficient to finish the immigration & customs, transfer from international to demstic, take the boarding pass , checkin my baggage and board the Yantai flight