Patent ID: 6834723
Filing Date: 2004-12-28
Classification: E21B

Abstract:
A riser recoil system for adjusting a plurality of tension forces applied to a riser conductor attached to a floating vessel, wherein the riser is adapted to be connected to and disconnected from a wellhead, comprising:a plurality of riser tensioners in mechanical communication with the vessel and the riser, each one of said plurality of riser tensioners having an air shutoff valve and an orifice-controlled fluid valve set to a first preselected flow limit value; and a disconnection sensing means adapted to provide a disconnect signal when the riser is disconnected from the wellhead, wherein application of the disconnect signal to the plurality of air shutoff valves and orifice-controlled fluid valves operates to adjust the plurality of tension forces applied to the marine riser by closing the plurality of air shutoff valves and closing the plurality of orifice-controlled fluid valves to a second preselected nonzero flow limit value, and wherein the first preselected flow limit value is greater than the second preselected nonzero flow limit value.