Would I be required a transit visa if I don't leave the airport and stay in the transit area?

Hi, I am planning to visit thailand from Dubai via Kunming. I will have a transit at Kunming for nearly 7hrs while flying from Dubai and while returning from Bangkok i have a transit at Kunming for nearly 21hrs. I am traveling on a Nepalese Passport.
Pls advice.
Regards
Rishav