Connection in China

You need a visa or different flights. Two stops limits you to 24 hours direct transit.

I would be flying in from Mongolia to Shanghai and from Shanghai to US. I'd be spending 2 days in Shanghai. My time in Beijing would just be 2 hrs at the airport making the connection I wouldn't bet getting a visa in Beijing. does that make a difference?

You are not flying Mongolia-Shanghai-US. You are flying Mongolia-Beijing-Shanghai-US. That requires a visa. Otherwise you will be denied boarding in Mongolia and will have no recourse. By the way, there is no such airline as “China Air”.

Sorry, landing in both Beijing and Shanghai is considered 2 stops in China thus limited to 24 hours direct transit. Beijing to Shanghai is considered a domestic flight and you cannot do domestic flights on the 72/144 hour transit without visa.

As for the comment about China Air. There is an airline called China Airlines but it travels through Taiwan and does not travel between two points in mainland China.

thanks for the clarification. I meant to say Air China