For a flight with a stop (the same plane with the same flight number) in China, you would have to deplane, go through immigration checks (in Dalian), and re-board the same aircraft. There is no need to go through security again.

If Beijing is your final destination, or if your bags are not checked through to another non-Mainland destination:

After you arrive in Beijing, you need to then go to the international baggage pick up area and go through customs for baggage inspection (green or red lanes as appropriate).

Note that there will also be domestic passengers on the plane (for Dalian-Beijing leg) whose baggage will not be in the same baggage carousel in a different arrival area.

Generally, you may get a card or a sticker identifying you as an international arrival and asked to take a shuttle to the international terminal/area. Ask for directions from the airlines staff when you are not sure.

I still need to check how a transfer to BKK would work in this case; the procedure is a little bit more complicated than normal International-International transfers in China since there is an immigration entry in China in Dalian already.

For a flight with a stop (the same plane with the same flight number) in China, you would have to deplane, go through immigration checks (in Dalian), and re-board the same aircraft. There is no need to go through security again.

For this reason, you need to have a Chinese visa or other travel facility (e.g., visa-free transit or visa on arrival) that allows you to make the Dalian-Beijing journey, regardless of what happens to your bags. The 24-hour visa-free transit does not apply (since you will enter and leave China at different ports); but the 240-hour visa-free transit policy may apply (but always check for the latest policy): both Dalian and Beijing are within the permitted areas of stay.

If Beijing is your final destination, or if your bags are not checked through to another non-Mainland destination:

After you arrive in Beijing, you need to then go to the international baggage pick up area.

You will go through customs for baggage inspection (green or red lanes as appropriate) and then you can check in and go through security for your next flight.

Note that there will also be domestic passengers on the plane (for Dalian-Beijing leg) whose baggage will not be in the same baggage carousel in a different arrival area.

Generally, you may get a card or a sticker identifying you as an international arrival and asked to take a shuttle to the international terminal/area. Ask for directions from the airlines staff when you are not sure.

If the bags are checked through to BKK:

I cannot advise certainly on what will happen. Most likely, you will still go with other international arrival passengers to the international arrival area (T3-E probably). Then you will ask the airport/customs staff to go to the international departure area; depending on the arrangement of the day, you may be permitted to go to the transit desks within the international customs area. However, you will most likely still need to go through security checks (since you have entered non-secure area: you could have picked up something from a checked bag).

For a flight with a stop (the same plane with the same flight number) in China, you would have to deplane, go through immigration checks (in Dalian), and re-board the same aircraft. There is no need to go through security again.

After you arrive in Beijing, you must go to the international baggage pick up area and go through customs for baggage inspection (green or red lanes as appropriate).

Note that there will also be domestic passengers on the plane (for Dalian-Beijing leg) whose baggage will not be in the same baggage carousel in a different arrival area.

Generally, you may get a card or a sticker identifying you as an international arrival and asked to take a shuttle to the international terminal/area. Ask for directions from the airlines staff when you are not sure.

For a flight with a stop (the same plane with the same flight number) in China, you would have to deplane, go through immigration checks (in Dalian), and re-board the same aircraft. There is no need to go through security again.

If Beijing is your final destination, or if your bags are not checked through to another non-Mainland destination:

After you arrive in Beijing, you need to then go to the international baggage pick up area and go through customs for baggage inspection (green or red lanes as appropriate).

Note that there will also be domestic passengers on the plane (for Dalian-Beijing leg) whose baggage will not be in the same baggage carousel in a different arrival area.

Generally, you may get a card or a sticker identifying you as an international arrival and asked to take a shuttle to the international terminal/area. Ask for directions from the airlines staff when you are not sure.

I still need to check how a transfer to BKK would work in this case; the procedure is a little bit more complicated than normal International-International transfers in China since there is an immigration entry in China in Dalian already.