Subsea tree workover control system

摘要

An electrical and hydraulic configuration on a subsea tree that facilitates the use of an ROV control system to operate the tree during well installations, interventions, and workovers. An SCM at the tree is in communication with a fixed junction plate that receives a production umbilical during normal operation. The ROV can be deployed to disconnect and park the production umbilical during well installations, interventions, and workovers to prevent accidental operation of the SCM or tree. The junction plate is configured to connect with the ROV and thereby establish communication with the hydraulic lines of the SCM. The ROV may carry an umbilical from a vessel to provide electrical and hydraulic service to the SCM during well operations. In addition, the ROV has facilities to repressurize spent control fluid to thereby allow reuse of the control fluid by the SCM.

主权项

1. A subsea well apparatus, comprising,
a subsea tree having a hydraulically-operated valve; and a control module with the subsea tree; a hydraulic line extending from the control module to the hydraulically-operated valve to operate the hydraulically-operated valve; an input receptacle in fluid communication with the control module and in selective fluid communication with a utility skid on a remotely operated vehicle (ROV), so that hydraulic fluid from the ROV is selectively supplied to the control module; an output receptacle in fluid communication with a hydraulic fluid return line extending from the control module and configured to direct hydraulic fluid to an external device; a subsea tree electronic module on the subsea tree that is controlled by an ROV electronic module on the ROV by signals communicated to the subsea tree electronic module from the ROV electronic module via a control line, and by power from a power source on a vessel via an electrical line that is part of a workover umbilical that has an end connected to a hydraulic fluid source.