Family short visit to Shanghai

Hi, I'll be flying to Shangai on duty as a Flight Crew member, and since the layover there is more than 50hrs, I was thinking on taking my Wife and 4yo daughter with me, Our Passports are all Portuguese but we're residents in Dubai, what is the procedure to get the visas for my family for this short stay in Shangai since I'm going there on work?
Thanks in advance