Cruise passenger Singapore-Tianjin-Hong Kong

My wife and I have valid US passports. We are currently scheduled on a Royal Caribbean Cruise ship leaving from Singapore on April 12th arriving in Tianjin China on the 26th of April at 6AM. My wife and I are planning on staying on the ship which leaves Tianjin 11 hours later at 5pm for Hong Kong. Does this stop over qualify for a TWOV or is a China VISA required for this portion of our cruise?