Answered by ZUPAN | Jan. 06, 2020 12:26
Your situation is very clear. You are definitely eligible for 24 hour visa free transit both ways and you don't need any kind of visa.
You will also print out your flight tickets and have those printouts with you. Also, you will declare at check-in in Frankfurt that you will travel to Thailand via Chengdu using 24 hour visa free transit. After a short check of your flight tickets, you will be allowed to board the plane. Here, at check-in you will ask about the luggage policy. Although your flight itinerary is on a single ticket, it is quite possible that you will have to collect your luggage upon arrival in Chengdu and perform a recheck for your flight to Thailand. This is not a problem at all, but you should be informed about this detail.
Upon arrival in Chengdu and assuming that you will have to collect your luggage, you will first approach 24 hour visa free transit counter where you will apply for a temporary entry permit to be allowed to collect your luggage and to perform a recheck for a flight to Thailand. You will do exactly as I have explained and after a recheck, you will wait for your flight to Thailand at a boarding gate.
For your second leg, from Indonesia to Frankfurt, you will do exactly the same, but if you are traveling on Air China single ticket, your luggage will be almost for certain be ragged all the way to Frankfurt. Regardless of what I have written, you will ask in Indonesia about this detail.
Upon your arrival in Beijing, you will clear a few formalities and you will not apply for a temporary entry permit, but you will remain within the transit zone of Beijing airport.
Basically, that's it.