Rolls-Royce has provided the 3,500-dwt UT 771 WP design for two firm contracts atCosco Guangdong.
They will be the first in Asia featuring its wave-piercing bow.
The deal comes with four options.
The firm vessels will be delivered in 2015.
Chellsea has two UT-type ships in the water currently. It wants to operate up to seven vessels in the next fiveyears.
