AU695016B2 - Device for remote control of components such as hydraulically actuated valves in the undersea environment - Google Patents

Description

AUSTRALIA

PATENTS ACT 1990 COMPLETE SPECIFICATION NAME OF APPLICANT(S): Societe ECA ADDRESS FOR SERVICE: o DAVIES COLLISON CAVE Patent Attorneys 1 Little Collins Street, Melbourne, 3000.

INVENTION TITLE: Device for remote control of components, such as hydraulically actuated valves, in the undersea environment The following statement is a full description of this invention, including the best method of performing it known to me/us:- C *0 C C 0 0CC C

C

C

CC

la The present invention relates to a device f or remote control of components, such as hydraulically actuated valves, in the undersea environment, particularly of valves of a wellhead of an undersea oilfield.

A wellhead of an undersea oilf ield is equipped with a structure situated on the sea bed, called a "Christmas tree" and including a large number of hydraulically actuated valves.

In conventional systems, the operation of the valves is performed from a central unit linked by flexible pipes to hydraulic actuators each associated with one valve.

These systems exhibit the drawback of being cumbersome and expensive and it has already been proposed to replace the central unit by a plurality of independent modules, called remote valve operators, which are cona trolled individually with respect to one another.

These independent remote valve operators appear to be the solution which is most closely matched to the ::..'problems of maintenance of wellheads, to the extent that the malfunctioning of an isolated remote operator does not entail the whole of the wellhead being put out of 25 service, as occurs in the event of failure of the central unit.

However, with each remote valve operator having to be connected individually to a control centre, such a device requires a large number of connections.

There has already been a suggestion to construct a network to which all the remote valve operators of the same wellhead would be connected, which would make it possible, for example, to reduce the number of connections necessary.

This solution, which is satisfactory a priori as f ar as the reduction in the number of connections is concerned, poses the problem, however, of the reliability of such a network in operation, the ever-present concern being to be forearmed against the risks of paralysis of i o)4-p 1 135795 Y N 6! -2the whole of the wellhead.

In fact, networking of remote valve operators does not boil down to simply connecting them to the same electrical circuit, particularly given the multiplicity of tasks which the various remote valve operators have to accomplish.

Thus, on a single wellhead, there are remote valve operators which operate in a radically different way from one another, some, furthermore, collecting sundry information received from sensors placed on the wellhead.

Consequently, it is necessary for the remote valve operators to be able, on the one hand, to all be linked to the same network and, on the other hand, to fulfil different roles on the wellhead, depending on the valve which they control.

The means making it possible to achieve such an object should furthermore be *i compatible with the conditions in which they are called on to operate, that is to say in the i ^undersea environment, possibly at great depth.

Embodiments of the invention provide a remote-control device specially adapted to static undersea installations, particularly valves of a wellhead, which meets these requirements, particularly as regards reliability.

The subject of the present invention is a device for remote control of hydraulically actuated components in the undersea environment, particularly of hydraulically actuated valves of a wellhead of an undersea oil field, including a plurality of modules linked in a network, each module being associated with one of the said hydraulically actuated components, characterized in that each module includes a microprocessor, an interface for connecting it to the network, a first electrically erasable and programmable non-volatile 7 memory, a second random-access memory for the operation of the microprocessor and output ports able to be connected to an actuator controlling the hydraulically actuated component, a start-up and loading programme being written into the first non-volatile memory and being setup to be automatically executed by the microprocessor when voltage is applied to the respective module, and to carry out the loading of specific software received by the interface into the first non-volatile memory.

Embodiments of the remote-control device according to the invention have the A advantage that each module can be adapted precisely to the specific tasks which it is desired 1 1 I&I. fht KA57 0.5 Yt4 14 A -3to entrust to it, without it being necessary to interfere with its hardware structure, hence under good reliability conditions.

In other words, the remote-control device according to these embodiments of the invention simultaneously exhibit the advantages of a device made-to-measure, perfectly adapted to the use which is made thereof, and those of a mass-produced device.

Embodiments of the invention are adapted to specific use in a purely logical way, so that each module of the remote-control device may, upon leaving the factory, be enclosed in a sealed box, only the interface and the output port being accessible from outside this box.

This advantage is significant in the field of the invention, namely the equipping of undersea installations, as the level of reliability required in this field is very high, particularly due to the cost of maintenance operations.

I Thus, whether at shallow depth, where a diver can operate, or at great depth, where a robot is necessary, it may be possible to dispense with maintenance attention for the ten to fifteen years which follow the equipping of the installation.

S 15 Moreover, the fact of being able to enclose each module in a sealed box makes the device according to embodiments of the invention fairly compact and relatively simple to repair when, despite everything, it proves to be necessary. The means employed for this repair may therefore be fairly lightweight.

1 In a preferred embodiment of the invention, the module further includes entry ports, i. 20 able to be connected j :1

T/

RiA.

v'

L

-4 to sensors, for example pressure or temperature sensors, which take measurements which can be processed in the microprocessor of the circuit and/or sent over the network towards a control centre.

According to the invention, each module of the device may be configured, that is to say that its first non-volatile memory may record software before it is put in place and installed on the network or thereafter, over the network.

In fact, the first software to be loaded automatically into the first non-volatile memory of the module by the microprocessor running the start-up and U: ':loading programme may make provision for the module to be able to be reconfigured over the network, while the a a~ 15 device is in use.

To a lesser extent, the software may also make a provision for some of its parameters to be able to be updated over the network.

With the aim of making the invention easier to understand, an embodiment thereof will now be described, given by way of non-limiting example, by reference to the attached drawing, in which: -Figure 1 diagrammatically represents an undersea '~:oil wellhead equipped with valves controlled by a device according to the invention, -Figure 2 functionally represents various modules of the device of Figure 1, which are linked in a network, Figure 3 diagrammatically represents the hybrid circuit of one of the modules of Figure 2.

Figure 1 represents a wellhead 1 equipped with a Christmas tree which includes several hydraulically actuated valves 2.

A hydraulic actuator 3 is associated with each valve 2.

An independent module 4, or remote valve operator, is connected to each hydraulic actuator 3 via a connecting box The various modules are linked over a network 6 and connected to an umbilical head 7.

6:- 5 Three of the modules 4 of Figure i, which are each enclosed in a sealed box able to maintain a pressure equal to the surrounding external pressure, have been represented diagrammatically in Figure 2.

These modules 4 are linked in a network by a link 6 which is shown symbolically in dots and dashes in Figure 2.

Each module 4 particularly comprises a solenoid valve 8 and an electronic circuit 9.

The solenoid valve 8 is fed with pressurized fluid via a duct 10 to which each module is connected, and sends this fluid to the actuator 3 of the corresponding valve 2.

Each module 4 is supplied electrically by means 15 of a current supply circuit 11.4 0Two of the modules 4 represented at the top of Figure 2 are furthermore linked to a sensor 12 which takes measurements on the wellhead.

The electronic circuit 9 of a module 4 has been 20 represented in Figure 3.

In such a circuit, the links are reduced as far as possible, which increases the reliability and the compactness of the module.

This circuit includes a microprocessor 13, for example the one sold under reference 68302 by the Motorola company, linked by a databus 14 and an address bus 15 to a first electrically erasable and programmable non-volatile memory 17 and to a second random-access memory 16.

A programmable logic array 18 is also linked to the microprocessor 13 by the databus 14 and address bus and by a control bus 19 which allows the said programmable logic array 18 to be configured by the microprocessor 13.

The programmable logic array 18 is linked to four analogue acquisition stages 20 and to eight input/output ports 21.

A first interface 22, of the RS 232 type, is linked to the microprocessor 13, and a second interface -6- 23, of Manchester 422 type, is linked to the programmable logic array 18.

o .094 .9 *0 4 C The microprocessor 13 is also linked to two power transistors 24 which control the current supplied to the solenoid valve 8 of the corresponding actuator 3.

With the solenoid valve 8 preferably being bistable, two solenoids are necessary for controlling it.

Moreover, for safety reasons, these solenoids are duplicated, which makes it possible, in the event of failure of one solenoid, to fall back on the other solenoid.

The current flowing in the solenoids is measured and its value is returned to the microprocessor 13, which can thus check the correct operation of the solenoids.

15 Two 20a, 20b of the four analogue acquisition stages 20 can be used to collect the measurements taken by sensors, not represented, placed for example on the Christmas tree, and a third 20c to receive the output pressure of the module 4 so as to verify that the sole- 20 noid valve 8 goes into action when it is selected, which translates into a rise in pressure in the valve actuation component.

The fourth analogue acquisition stage 20d, as well as the eight input/output ports 21, are available 25 for various uses which will not be described here.

The programmable logic array 18 is configured so as, on the one hand, to carry out the biphase coding necessary for communication over the network via the Manchester interface 23, and, on the other hand, to convert the signals originating from the analogue acquisition stages 20 into digital information which can be interpreted by the microprocessor 13.

In accordance with the invention, the first nonvolatile memory 17 initially contains a start-up and loading programme which is automatically run by the microprocessor 13 when voltage is first applied to the module 4.

This start-up and loading programme is identical for all the modules.

4 05 4

SOSC

SC.

S. S S 7 When it is run, this programme makes it possible to write into the first non-volatile memory 17, which is electrically programmable, specific software received by the RS 232 interface 22, software which the microprocessor 13 will run when the module is put in place on the wellhead.

The RS 232 interface 22 is therefore intended to be used only once, when the electronic circuit is first configured.

The signals are then sent to the circuit over a service network 25 connected to the interface 22.

In particular, in one variant, the electronic circuit includes only a single interface 23 which serves both for the first downloading of specific software and S" 15 for connection to the network 6.

Advantageously, the software thus downloaded includes parameters which can be updated over the network 6 which is linked to the Manchester interface 23.

In one variant, the whole of the specific soft- 20 ware can be erased, new specific software being again downloaded over this network.

The advantage of a circuit such as the one which has just been described lies in the fact that it can be mass-produced, the specific nature of each example being T .h 25 introduced subsequently by downloading software specific to each module.

This logic adaptation of the circuit further exhibits the advantage of allowing the module to be I isolated within a sealed box resistant to the immersion pressure, by virtue, for example, of an inert dielectric fluid which occupies the whole of the internal volume of the box.

Moreover, the fact that access to the interior of the module is impossible contributes to enhancing the reliability of the latter by preventing any untoward interference with the elements of which it consits.

It is obvious that the embodiment which has just been described exhibits no limiting nature and that it can accommodate any desirable modification without -8- Ihe reference numerals in the following claims do not in any way limit the scope of the respective claims.

i:.

a *1 ft t

Claims (3)

1. 2. D evice according to Ch'fiml 1 characterized inl that each modul kicrther includes entry 15 ports able to be connected to sensors, for example pressure Or tell )Crattilre senlsor.
2. 3. D evice according to either of C lainis I and( 2, characterized inl that thie interfaice may fu r-ther receive niew specific software, over thle network, to be written into the fi rst nlonl volatile memiory inl p lace of previously downfoaded speciftic soitxvare.
3. 4. A device For renlot control of' hydraulically actuated components inl the undersea environment substantially as hecreinbef'ore described with ref crence to the drawings. DATED this 18thi day of June, 1998 SOCIETE I3CA Byv its patent attorneys Davies Collison Cave ABSTRACT Device for remote control of components, such as hydraulically actuated valves, including a plurality of .modules linked in a network, each module being associated with one of the said hydraulically actuated components. S0 Each module includes a microprocessor (13), 4" an interface (23) for connecting it to the network first electrically erasable and programmable non- volatile memory a second random-access memory (16) for the operation of the microprocessor (13) and output ports (24) able to be connected to an actuator control- ling the hydraulically actuated component, a start-up and loading programme being written into the first non- e 1 volatile memory (17) and being set up to be automatically executed by the microprocessor (13) when voltage is applied to the module and to carry out the loading of specific software received by the interface (23) into the first non-volatile memory (17).