Hudong-Zhonghua Shipbuilding Co, a unit of China State Shipbuilding Corp [SASACN.UL], has signed contract to construct three liquefied natural gas (LNG) carriers worth 3.9 billion yuan ($551.62 million).

The LNG carriers, each with a capacity of 174,000 cubic metres, will be operated by China's COSCO Shipping Energy Transportation, a unit of COSCO Shipping.

The carriers will be deployed for LNG shipping services for PetroChina International Co, an affiliate of China National Petroleum Corp [CNPET.UL].

The three vessels are expected to be delivered between late 2022 and early 2023, a spokesperson at Hudong-Zhonghua told Reuters on Wednesday, adding the carriers will adopt XDF type of propulsion and a membrane type containment system.

Liu Hanbo, chairman of COSCO Shipping Energy Transportation, said the construction of the new LNG carriers is in response to the government's call to expand domestic demand and to safeguard China's energy security.

COSCO Shipping Energy will own 41 LNG carriers once the new vessels are completed, with combined capacity of 6.94 million cubic metres.

Hudong-Zhonghua in April won a $2.8 billion worth contract to build LNG carriers for Qatar Petroleum, the biggest export LNG vessels construction contract ever received by a Chinese shipyard.

($1 = 7.0701 Chinese yuan)

(Reporting by Muyu Xu and Tom Daly, editing by Louise Heavens and Shailesh Kuber)