Transit in Shanghai

Your itinerary is definitely eligible for 24 hour visa free transit and you do not need any kind of visa.

I encourage you to use correct terminology because in your case there will be no visa of any kind. You will be in a status of a passenger in 24 hour visa free transit, so no visa will be issued. If you want to exit the airport to have a good night rest or to explore the city, the first thing you will do is to approach transit counter upon your landing in Shanghai. Before that you will fill out your arrival/departure card that will be dispensed on board the plane from Sapporo to Shanghai where you will tick - transit. At the transit counter you will apply for a temporary entry permit in order to be allowed to exit the airport. Here you will present your flight tickets as well as your accommodation booking confirmation. After a short check, your permit will be granted and you will proceed to immigration in order to exit the airport. Here I have to tell you that a granting of a temporary entry permit is never a guaranteed detail, but it belongs to a discretionary decision of the airport officials on the day. In any case, you do not need any kind of visa and you are ready to go.