Use the Transit via Twice on return Flight

Hi, is it possible to use the Transit visa on both ways? e.g. we are coming from Germany to shanghai on May 22th, stay around shanghai till 29th (the 6th day from the day after our arrival) and continue our journay to Hong Kong. Then we stay in Hongkong from 29th to June 2nd, return to shanghai, use the transit visa one again for 1 night and fly back on june 3rd to germany. Would this route work?
Kind regards and thanks for helping,
Julius