I will arrive Tianjin at 7am with oviation of the sea (royal caribean)

If the last country you come from by sea is not USA, you are eligible for the 24 hour direct transit in China. No visa will be needed then.

Nick,
thanks for your reply. I am receiving all kind of response on this research.
we will come from Soul (Korean) before arriving Tianjin.
for 24 hours free transit rule, some one said it only applies to flight in and flight out at airport but some one said it can applies to cruise ship in and flight out.
someone said it does not allow multiple cities but some one said it is ok . (Tianjin - Beijing).
your first response said you called Tianjin port and replied that no one can leave port without a visa.
why so confused?
I call LAX china visa dept. they said in my case ((Tianjin - Beijing), it is not transit. of course she could be wrong. so who is really right on this???

Based on what I know, if your travel route is country A-China (transit in both Tianjin and Beijing within 24 hours)-country B, you will be able to enjoy the 24 hour direct transit in China, and you can transit in more than one Chinese city. However, nobody can assure that. The consulate general may not know the specific situation. You are usually advised to confirm that with the cruise ship company in case that you are not allowed to board the ship.

Nick,
I have asked ship company (Royal caribean ) as well. they dont' know either.
they tell me to get visa to cover themselves!
china visa dept want me to get visa too so they can make money.
I feel I can use that 24 hours rule but no one wants to take responsibility to tell me that clearly. I think maybe that rule is not clean cut in China so sometimes it works and sometimes it does not work.