Abstract: A control system for monitoring a filter in a subsea control module (SCM) of an underwater hydrocarbon well is presented. The control system includes an upstream pressure transducer disposed upstream of a filter of the SCM and configured to sense an upstream pressure. The control system further includes a downstream pressure transducer disposed downstream of the filter and configured to sense a downstream pressure. Furthermore, the control system includes a subsea electronics module (SEM) coupled to the upstream pressure transducer and the downstream pressure transducer. The SEM is configured to determine average pressure differential values at different instances based on the upstream pressure and the downstream pressure. Moreover, the control system also includes a master control station (MCS) coupled to the SEM and configured to predict a filter maintenance generate an indication of the predicted filter maintenance due time for an operator of the underwater hydrocarbon well.

Abstract: A control system for monitoring a filter in a subsea control module (SCM) of an underwater hydrocarbon well is presented. The control system includes an upstream pressure transducer disposed upstream of a filter of the SCM and configured to sense an upstream pressure. The control system further includes a downstream pressure transducer disposed downstream of the filter and configured to sense a downstream pressure. Furthermore, the control system includes a subsea electronics module (SEM) coupled to the upstream pressure transducer and the downstream pressure transducer. The SEM is configured to determine average pressure differential values at different instances based on the upstream pressure and the downstream pressure. Moreover, the control system also includes a master control station (MCS) coupled to the SEM and configured to predict a filter maintenance generate an indication of the predicted filter maintenance due time for an operator of the underwater hydrocarbon well.

Abstract: A production control system for an underwater well, comprises: first electrically operated means for supplying first hydraulic fluid, for opening a first control valve of the well; second electrically operated means, for supplying second hydraulic fluid at a higher pressure than said first fluid, for opening a further control valve of the well; electronic circuitry (SEM1) for providing electrical power for operating said first and second means; and means for controlling the sequence of closing said control valves as a result of a loss of electrical power from said electronic circuitry. The controlling means comprises: electrical power storage means; detection means responsive to said loss of power from said electronic circuitry; and means coupled with said detection means for using electrical power from said storage means to keep said further control valve open for a period after closure of said first control valve and close it after said period.

Abstract: A hydraulic circuit for supplying hydraulic fluid to a subsea control module of a control system for an underwater hydrocarbon well, the hydraulic circuit including an input for hydraulic fluid, a filter connected with the input for filtering hydraulic fluid from the input, an output for supplying hydraulic fluid from the filter to the subsea control module, first sensing means for sensing pressure of hydraulic fluid from the input upstream of the filter, second sensing means for sensing pressure of hydraulic fluid downstream of the filter, and a subsea electronics module in the subsea control module, the subsea electronics module being coupled with the first and second sensing means and being adapted to produce an indication related to a hydraulic fluid pressure differential across the filter.

Abstract: A production control system for an underwater well, comprises: first electrically operated means for supplying first hydraulic fluid, for opening a first control valve of the well; second electrically operated means, for supplying second hydraulic fluid at a higher pressure than said first fluid, for opening a further control valve of the well; electronic circuitry (SEM1) for providing electrical power for operating said first and second means; and means for controlling the sequence of closing said control valves as a result of a loss of electrical power from said electronic circuitry. The controlling means comprises: electrical power storage means; detection means responsive to said loss of power from said electronic circuitry; and means coupled with said detection means for using electrical power from said storage means to keep said further control valve open for a period after closure of said first control valve and close it after said period.