Introduction
The document discusses the development of new Ocean Bottom Cable (OBC) vessels for offshore seismic exploration by Chinese Seismic Exploration. These vessels are designed for specific tasks related to seismic sourcing and recording.

Specifications
The vessels are twin-screw, medium-speed propulsion packages, each 65 meters in length. They are equipped with MAN B&W Diesel propulsion systems, featuring low vibration and noise levels crucial for seismic operations. The vessels are classified under the China Classification Society with an Ice Class B rating.

Design and Construction
The design is managed by Dalian Shipbuilding Technology Research Center Co. Ltd., and construction is by Liao Nan Shipyard. The first vessel is expected to be delivered by the end of next year. The operator and owner is BGP/CNPC.

Propulsion System
The propulsion system includes two MAN B&W Alpha type VB560 four-bladed controllable pitch propellers, with a diameter of 1,900 mm. The system also includes tail shafts, intermediate shafts, bearings, and stern tube equipment. The control system features the Alphatronic IIA Propulsion Control and Safety System.

Engine Details
The vessels are powered by two MAN B&W 6L23/30A-D engines, each developing 960 kW at 900 r/min. The engines are mounted with a resilient seating arrangement to minimize vibrations.

About CNPC and BGP
CNPC is a leading integrated energy company in China, involved in various upstream and downstream activities. BGP, a subsidiary of CNPC, specializes in geophysical prospecting and has extensive experience in shallow water seismic operations.

Conclusion
The new OBC vessels represent a significant advancement in seismic exploration technology, emphasizing low noise and vibration levels to enhance operational efficiency and data accuracy.