With depths as deep as 10,000ft (3,000m) flow measurement in subsea oil and gas production systems represents a challenge for flow measurement. The complexity of subsea production systems ranges from single satellite wells with independent tie back lines to complex multiple well sites with a network of lines, manifolds and other modules. Often times multiple production lines feed a single vertical riser leading to the surface and eventually extend to a fixed platform, floating production storage and offloading vessel (FPSO), or a pipeline running to a land-based operation. At the same time, enhanced oil recovery (EOR) techniques push gas and liquid back to the ocean floor and deeper to more well sites and tie backs. By Nicholas Voss, V-Cone® Product Manager, McCrometer, Inc.