This study proposes and validates computationally the effectiveness of a novel, hemiwedge model for a sub-surface safety valve (SSSV). With the growing needs in the oil industry and new finds of ultra-deepwater reservoirs in the Gulf of Mexico (GOM), this SSSV will provide a small but necessary advancement to harvest these new oil reserves from extreme high-pressure/high-temperature (XHPHT) environments. Computational fluid dynamics (CFD) in the Ansys RTM CFX flow solver is used to study the flow properties of crude oil through the valve, while both AnsysRTM and SolidWorks RTM Simulation are used to perform stress and fatigue analyses and other solid mechanics studies. Analysis has shown this model to be effective in successfully and safely operating at high pressures (30,000 psi ) and high temperatures (450°F) over the desired life of the SSSV, providing a viable option for helping to recover new oil reserves found in the GOM and other XHPHT environments.