Multiple visit to Beijing.

I will be travelling from Rome to Beijing on 08/May until 08/June with a Regular double entry Chinese Visa that I have received from Embassy in Italy.
I will then need to make 3 trips to Hong Kong and Bangkok during my stay in China as follows:
14 to 18 May Hong Kong
21 to 25 May Bangkok
28 to 01 June Hong Kong
04 to 07 June Bangkok
Can I apply for 144 hour (or 72 hour could be sufficient) free transit each time I return to Beijing from these trips? Practically It would mean 3 "long" weekends of May and June...
OK?