Abstract: A method of mounting a subsea control module (1) on a mounting plate (10) of an underwater tree of a subsea hydrocarbon well comprises lowering the module to the plate and attaching the module to the plate with an adapter (6) between it and the plate and with portions of the module being coupled with portions of the mounting plate.

Abstract: A subsea control module has a casing inside which there is at least one pair of electrodes, there being electronic means connected with the electrodes of the or each pair for monitoring at least one electrical characteristic between the electrodes as a result of a fluid to which the electrodes are exposed. This can include, for example, a change due to an ingress of seawater and/or an ingress of hydraulic fluid into the interior of the casing. The or each pair of electrodes include an array in which each electrode of the pair has finger portions interleaved with finger portions of the other electrode.

Abstract: An electronics module for a well installation configured to receive software via a wireless connection and methods of installing software on an electronics module for a well installation, are provided. An example of such electronics module comprises a short-range wireless receiver for wirelessly receiving software and/or data from an external wireless source. Modem external interface wiring can be employed as an antenna for the wireless receiver to receive the wireless transmission of the software and/or data.

Abstract: A hydraulic intensifier comprising a reciprocating differential piston arrangement and a controller configured to control the supply of low pressure hydraulic fluid to the intensifier is provided. The controller comprises at least one solenoid operated pilot valve and electronic operator configured to operate the pilot valve.

Abstract: A method of testing a fuse in apparatus for monitoring electrical insulation surrounding first and second electrical conductors in a cable, the fuse being connected to the conductors, comprises: applying an electrical signal, with respect to a reference, to the fuse from a source; obtaining a value for the resistance of the insulation with respect to the reference; determining if the resistance value is greater than a fuse test resistance threshold and, if it is, causing the application of the signal to cease; and monitoring the decay of the signal to determine if the time for it to decay below a set value exceeds a set time limit, indicative of the fuse being satisfactory, or is less than the limit indicative of the fuse being blown.

Abstract: A stabplate connection is provided by: providing a first part (1) comprising a stabplate and carried by an underwater structure; providing a second part (2) comprising a stabplate carried by tooling (4); engaging the tooling with said first part; using the tooling to bring the parts together so the stabplates mate with each other; using the tooling to lock the first and second parts together by engaging a portion (6) carried by the first part with a portion (10) carried by the second part; disengaging the tooling from the first part; and removing the tooling from the stabplate connection.

Abstract: A method for providing auxiliary electrical power to an underwater well installation, the installation being linked to a surface location via an umbilical cable, to supplement any electrical power received at the installation from the umbilical cable, comprises the steps of: providing power generation means at the installation; and providing an electrical power output line for transferring electrical power generated by the power generation means to the installation.

Abstract: A production shutdown system for an underwater hydrocarbon production facility, comprising, on the topside: a safety system, and a communications module; and, underwater; drive control means, and an underwater communications component; wherein in use safety signals are passed from the safety system to the drive control means via the topside communications module and the underwater communications component, and wherein the safety system and drive control means are rated according to a prescribed safety level but the communications module and underwater communications component are not so rated.

Abstract: A method of enabling communication between components of a hydrocarbon extraction plant, the plant having an underwater hydrocarbon extraction installation including at least one hydrocarbon extraction well with an associated tree, comprises providing a plurality of RF communication means at respective components of the installation.

Abstract: An apparatus is provided. The apparatus comprises a housing, a body defining a first chamber and an elongate actuator member mounted for reciprocal movement, at least a part of the actuator member being enclosed by the housing. The apparatus further comprises a seal compartment between the first chamber and a compartment of the housing, the actuator member extending from the housing to the first chamber through the seal compartment. The seal compartment comprises a fluid filled seal chamber enclosing at least a portion of the actuator member and located within the housing, wherein a volume comprising a volume between the fluid filled seal chamber and the actuator member remains substantially constant during movement of the actuator member.

Abstract: A method of monitoring an electrical power switching module of an underwater installation, the power switching module being operable to switch AC power in use is provided. The method includes the steps of measuring at least one operating parameter of the power switching module and producing a signal indicative of the measured parameter; if the signal is not digital, then converting the signal into a digital format; and outputting the digital signal on a bus. A power distribution unit for an underwater installation is also provided.

Abstract: A mechanism for clamping first and second stabplates together comprises a pivoted cam member and clamping means for co-operating with the cam member. The mechanism is such that the cam member is displaceable between a first position in which, in co-operation with the clamping means, it clamps the stabplates together and a second position in which it has rotated to be between the stabplates with the stabplates separate from each other.

Abstract: A method of operating an acoustic sand detector deployed at a flowline within a flow system, the detector comprising an acoustic sensor and functioning to produce electrical output signals in dependence on acoustic signals detected by the acoustic sensor, the acoustic signals being at least partially produced by the impact of sand particles within the flow on an object is provided. The method comprises estimating the location of particle impacts on the flowline; and weighting the output signals according to the distance between the estimated location and the detector location.

Abstract: A subsea control module has a casing inside which there is at least one pair of electrodes, there being electronic means connected with the electrodes of the or each pair for monitoring at least one electrical characteristic between the electrodes as a result of a fluid to which the electrodes are exposed. This can include, for example, a change due to an ingress of seawater and/or an ingress of hydraulic fluid into the interior of the casing. The or each pair of electrodes include an array in which each electrode of the pair has finger portions interleaved with finger portions of the other electrode.

Abstract: A method for monitoring the condition of apparatus located at an underwater facility that includes sensing at least one parameter associated with the apparatus, providing a model of expected behavior of said at least one parameter, comparing said sensed parameter with said model, and assessing the condition of the apparatus based upon said comparison.

Abstract: A Subsea Electronics Module for a well installation, comprising: a housing; at least two printed circuit boards having control circuitry provided thereon; and a communications component for enabling communication between the control printed circuit boards; wherein the module further comprises a communications handling board operatively connected to the printed circuit boards, the communications component being mounted on the communications handling board.

Abstract: An electronic module for use as a subsea electronic module for an underwater fluid extraction well, wherein a local area network enables communication within the module, the local area network including a plurality of interfaces with components of the network, and wherein the interfaces comprise capacitive coupling interfaces.

Abstract: A grease delivery system for delivering grease to a location is provided. The grease delivery system comprises: a first grease reservoir having a first grease output and a first output device configured to output grease from the first grease reservoir; a second grease reservoir having a second grease output and a second output device configured to output grease from the second grease reservoir; and a common grease output for delivering grease to the location, wherein the common grease output is fluidly connected to the first and second grease outputs, wherein the system is configured to simultaneously output grease from the first and second grease reservoirs to the common grease output.

Abstract: A system for transmitting alternating current power and communication signals between a first location and a second location through a communication path which includes at least one inductive load and at least one switch configured to switch power to the at least one inductive load on and off is disclosed herein. The system comprises a control configured to control the at least one switch so that, if the power is switched on during a particular phase of the power, is the power is switched off during the opposite phase of the power, and if the power is switched off during a particular phase of the power, the power is switched on during the opposite phase of the power.

Abstract: A system for transmitting electrical power and communication signals is provided. The system comprises a transmission line, a source of electrical power for supplying electrical power to the transmission line, a first communication unit configured to supply communication signals to the transmission line, a power extraction unit configured to extract and use electrical power from the transmission line, a second communication unit configured to receive communication signals from the transmission line; and a control unit configured to control operation of the system. The source supplies electrical power to the transmission line for respective periods of time which are different from respective periods of time in which the first communication unit supplies communication signals to the transmission line.