1.30h to take a domestic flight in Beijing

I’ve booked a flight with Air China from Beijing to Kulin and it’s the same terminal (T3), right? But I’ll need to go through immigration control and I won’t have to worry about my checked luggage because it goes directly to Kulin, correct? They handle that. They’ve given me about an hour and a half for the connection — is that enough time to get from immigration to the departure gate? I would like a very detailed map of this area. Can anyone help by telling me exactly where the Kulin gates are so I don’t waste time? Do you think that’s enough time?