Subsea riser manifold with structural spanning member for supporting production riser

A subsea riser manifold system for handling marine well fluids from multiple subsea wells and transmitting the well fluids to a surface facility comprising:

• a riser system including a buoy located below the surface of the water, a lower rigid section extending vertically downwardly from and maintained under tension by said buoy, and an upper flexible section between said buoy and the surface facility;
• said lower rigid section including a plurality of lower section flowlines supported by said buoy, and a strength member;
• said upper flexible section including a plurality of flexible flowlines, each connected to a respective one of said lower section flowlines;
• a marine floor base template including a support structure and a plurality of pile guides connected to the template for fixing the template to the marine floor;
• a sealed manifold chamber hull mounted on said support structure between said pile guides;
• a structural spanning support member extending over said hull for receiving and supporting said strength member;
• said spanning member having an upper riser-receiving platform portion vertically spaced from said hull, and a plurality of spanning arms extending downwardly and outwardly from said platform portion, each of said spanning arms being connected to a respective one of said pile guides;
• and
• said hull comprising manifold means therein for operatively connecting the subsea wells through said spanning member to said lower section flowlines, and means for maintaining a low pressure atmosphere;
• whereby the buoyed riser load is transmitted directly to the pile guides through said spanning member.