It has contracted a single emergency response and rescue vessel with Cosco Corp (Singapore), the shipyard said in a statement.
Sentinel will have six months to decide on doubling the deal with an optional newbuilding.
Cosco Guangdong will construct the firm vessel for delivery in the first quarter of 2017. No price has been disclosed.
In March, Sentinel chalked up a pair of 150 tbp anchor handlers at Xinlian Shipyard in China.
