WO2000073618A1

WO2000073618A1 - System and method for actuating a remote device

Info

Publication number: WO2000073618A1
Application number: PCT/US2000/015003
Authority: WO
Inventors: Thomas Michael Deaton
Original assignee: Halliburton Energy Services, Inc.
Priority date: 1999-06-01
Filing date: 2000-06-01
Publication date: 2000-12-07
Also published as: AU5591400A

Abstract

According to an embodiment of the invention, a system is provided which includes a source of infra-red or ultra-violet energy (12). A slave unit (14) is connected to a device, where the device can be a safety valve (20) or a flapper valve assembly (38) in a wellbore, at a remote location from the energy source (12), and a transmission line (10) transmits the energy from the source (12) to the slave unit (14). The salve unit (14) responds to the energy received from the transmission line (10) and adapted to convert energy to a mechanical output for actuating the device. The slave unit (14) can be in the form of a member (30) or bellows (34) that expands, where fluid within the bellows (34) expands, in response to being exposed to the energy from the transmission line (10). The expansion of the member (30) and the bellows (34) produce a mechanical output in the form of linear motion.

Description

SYSTEM AND METHOD FOR ACTUATING A REMOTE DEVICE

Cross-Reference to Related Application

This application relates to, and claims the priority of, provisional application S.N. 60/136,750 filed on June 1, 1999. Background of the Invention

This invention relates to a system and method for actuating a remote device, and, more particularly, to such a system and method that in which a transmission line is used to transmit radiated energy to operate a slave unit to actuate the device.

There are many potential applications for systems for actuating a remote device. For example, in the operation of subsurface equipment in an oil well environment, it is often necessary to operate a subsurface safety valve from the surface. Most existing systems designed for this purpose utilize hydraulic and electric control lines connected between the actuator and the subsurface safety valve. However, these systems are less than optimum since they are cumbersome, difficult to operate, and take up a great deal of space. Also, they create resistance, current leakage, noise and hazzards.

Therefore, what is needed is an actuating system of the above type that eliminates hydraulic and electrical lines. Summary of the Invention

According to an embodiment of the invention, a system is provided which includes a source of radiated energy. A slave unit is connected to a device to be actuated at a remote location from the energy source, and a transmission line transmits the energy from the source to the slave unit. The slave unit responds to the energy received from the transmission line and is adapted to convert the energy to a mechanical output for actuating the device.

The slave unit can be in the form of a member that expands in response to being exposed to the energy from the transmission line, or a bellows containing fluid that is also exposed to the energy from the transmission line for expanding and causing a corresponding expansion of the bellows. The expansion of the member and the bellows produces a mechanical output in the form of linear motion.

The device can be in the form of a safety valve located downhole in a well, or a flapper valve assembly. A significant advantage is thus obtained by the system since it eliminates the need for electrical and/or hydraulic control lines, and their attendant disadvantages, for connecting the energy source to the remote device. Brief Description of the Drawings

Fig. 1 is a schematic view illustrating the basic concept of an embodiment of the present invention.

Fig. 2 is a schematic view illustrating the system according to an embodiment of the present invention.

Figs. 3 and 4 are schematic views depicting alternate embodiments of the slave unit of the system of Fig. 2. Fig. 5 is a schematic view of an alternative embodiment of the system of Fig. 2.

Description of the Preferred Embodiments

Referring to Fig. 1 of the drawings, the reference numeral 10 refers to a transmission line 10 that connects a radiated energy source 12 with a slave unit 14. The slave unit 14 is adapted to convert the energy received from the source to a mechanical output which is used to actuate a device 16 located at a remote location from the energy source.

The transmission line 10 is preferably in the form of a conventional fibre optic cable, or waveguide. The radiated energy source 12 can be a laser, a diode laser, or other similar device, all of which are capable of outputting infra-red or ultra-violet energy. An example of this type of energy source 12 is a thirty watt diode laser, such as model OPC-BO30-FCTS manufactured and distributed by the Opto Power Corporation. This unit outputs radiated energy in the form of infra red energy and includes selectable output power and pulse duration. The slave unit 14 can be one of many known devices that converts the energy from the energy source to a mechanical output, and two examples of such a slave unit will be described. Thus, infra-red or ultra-violet energy, or power, from the source 12 can be focused into the transmission line for transmission to the slave unit 14 to actuate it. It is understood that a control signal is also transmitted which could be the same as, or different from, the transmitted power.

An example of an application of the concept of Fig. 1 is shown in Fig. 2 in a sub- surface oil well environment in which the device to be actuated is a safety valve 20 extending in a well 22. The safety valve 20 is connected to a tubing string 24 which extends from above ground to the valve. In this example, the energy source 12 is located above ground and receives a control signal from a conductor 26. The slave unit 14 is mounted adjacent the safety valve 20, and the transmission line 10 extends from the radiated energy source 12 into the well and is connected to the slave unit which, in turn, actuates the valve 20. Details of how the slave unit 14 actuates the valve 20 will be described.

In accordance with the embodiment of Fig. 3, the slave unit 14 is in the form of a member 30 fabricated from metal, or another material, having a relatively high coefficient of expansion. The member 30 is machined to form a recess, or groove, 30a to increase its surface area to permit increased heat transfer. The member 30 is positioned proximate to the end of the transmission line 10 opposite the end that is connected to the energy source 12. The spacing between the member 30 and the latter end of the transmission line 10 is such that the member is exposed to sufficient radiated energy from the line 10 to cause the member to expand a predetermined amount and produce a mechanical output in the form of linear motion. The increased surface area provided by the machined member 30 permits a more effective transfer of the heat energy from the energy source 12 to the member 30 and thus causes increased expansion and linear motion of the member. If the member 30 is used as the slave unit 14 of Fig. 2, the member would be directly connected to the safety valve 20 which is designed to be actuated in respond to an input corresponding to linear motion. Thus, upon activation of the energy source 12, and the transmission of the energy through the transmission line 10 to the member 30, the resultant linear motion output of the member actuates the safety valve 20. The amount of power transmitted from the energy source 12, via the transmission line 10, as well as the position of the member 30 relative to the corresponding end of the transmission line, are adjusted so that the member 30 expands a predetermined amount so that the linear motion is sufficient to actuate the safety valve 20.

In accordance with the embodiment of Fig. 3, a bellows 34 functions as the slave unit and contains a fluid which expands in response to the presence of the energy transmitted by the transmission line 10. The bellows 34 is positioned relative to the end of the transmission line 10 opposite the end that is connected to the radiated energy source such that the bellows is exposed to sufficient energy from the line 10 to cause the fluid in the bellows to expand a predetermined amount. This causes corresponding expansion of the bellows 34 which produces a mechanical output in the form of linear motion.

If the bellows 34 is used as the slave unit 14 of Fig. 2, the bellows would be directly connected to the safety valve 20, which is designed to be actuated in respond to an input corresponding to linear motion. Thus, upon actuation of the radiated energy source 12, and the transmission of the energy through the transmission line 10, this energy heats the fluid in the bellows 34 causing expansion of it and the bellows. The amount of power transmitted from the energy source 12, via the transmission line 10, as well as the position of the bellows 34 relative to the corresponding end of the transmission line, are adjusted so that the bellows expands a predetermined amount to provide a mechanical output in the form of linear motion sufficient to actuate the safety valve 20.

Fig. 5 depicts an alternate embodiment of the device to be actuated which, in this case is a flapper valve 38. The flapper valve 38 includes a housing 40 in which a link member 42 is pivotally mounted. The slave unit 14 is connected between the link member 42 and the transmission line 10, which, in turn, is connected to the energy source 12 as discussed above. It is understood that the slave unit 14 can be in the member 30 or the bellows 334 according to the embodiments of Figs. 3 and 4, respectively.

The link member 42 is pivotally connected to a rod 44 which is mounted for axial movement in the housing 40. The rod 44 is connected at one end to a disc-shaped valve 46 which is pivotally mounted in the housing 40.

A valve seat 48 is provided in the housing 40 and is engaged by the valve 46 in its closed position as shown by the solid lines in Fig. 5. One end of a spring 50 is mounted to a mounting member 52 in the housing 40, and the other end of the spring is connected to the valve 46 to normally urge it towards the seat 48. In operation of the embodiment of Fig. 5, activation of the radiated energy source 12 supplies energy that is transmitted through the transmission line 10 to the slave unit 14 resulting in a mechanical output, in the form of linear motion, from the slave unit, in the manner described above. This motion pivots the link member 42 in a direction to the left, as viewed in Fig. 5, and therefore pivots the valve 46 in the same direction and to its open position, as shown by the phantom lines, against the force of the spring 50. When the energy source 12 is deactivated, the linear motion from the slave unit 14 will terminate, causing the spring 50 to force the valve 46 back to its closed position in engagement with the valve seat 48. This movement of the valve 46 to its closed position causes corresponding movement of the rod 44 and the link member back to their positions shown in Fig. 5. It can be appreciated that the flapper valve 38 can thus be used as control device for controlling the flow of fluid through the housing 40 and in fact could be used as the safety valve 20 in the embodiment of Fig. 2.

It is understood that variations can be made in the foregoing without departing from the scope of the invention. For example, the slave unit 14 can take other forms, such as a bimetallic device, a photovoltaic device, a fibre-based device, or the like. Also, the radiated energy from the source 12 could be utilized in other manners such as, for example, ablating animal tissue for various medical purposes. Further, the energy source could be in the form of microwave energy, acoustic energy, or the like.

Since other modifications, changes, and substitutions are intended in the foregoing disclosure, it is appropriate that the appended claims be construed broadly and in a manner consistent with the scope of the invention.

Claims

What is claimed is:

1. A system for actuating a valve downhole in a well, the system comprising a source of radiated energy, a slave unit connected to the valve at a remote location from the energy source, and a transmission line for transmitting the energy from the source to the slave unit, the slave unit responding to the energy received from the transmission line and adapted to convert the energy to a mechanical output for actuating the valve.

2. The system of claim 1 wherein the energy source is a source of radiated energy.

3. The system of claim 1 wherein the energy source is a source of infra-red or ultra-violet energy.

4. The system of claim 1 wherein the transmission line is fibre optic cable.

5. The system of claim 1 wherein the transmission line is a waveguide.

6. The system of claim 1 wherein the slave unit is adapted to expand in response to the transmission of the energy thereto to produce the mechanical output.

7. The system of claim 1 wherein the slave unit comprises a member adapted to expand in response to the transmission of the energy thereto to produce a mechanical output in the form of linear motion.

8. The system of claim 7 wherein the member is machined to provide increased heat transfer surfaces to receive the energy.

9. The system of claim 1 wherein the slave unit comprises a bellows containing fluid that expands in response to the transmission of the energy thereto.

10. The system of claim 9 wherein the expansion of the fluid causes linear motion of the bellows to produce the mechanical output.

11. A valve assembly comprising a housing having an inlet for receiving a fluid and an outlet for discharging the fluid, a valve member movable in the housing between an open position in which it permits fluid flow through the housing and a closed position in which it prevents fluid flow through the housing, means for urging the valve to one of the positions, a source of radiated energy located externally of the housing, a slave unit disposed in the housing, a transmission line for transmitting the energy from the source to the slave unit, the slave unit responding to the energy received from the transmission line and adapted to convert the energy to a mechanical output, and a link system operatively connected between the slave unit and the valve and adapted to respond to the mechanical output for moving the valve to the other position.

12. The assembly of claim 11 wherein the energy source is a source of radiated energy.

13. The assembly of claim 11 wherein the energy source is a source of infra-red or ultra-violet energy.

14. The assembly of claim 11 wherein the transmission line is fibre optic cable.

15. The assembly of claim 11 wherein the transmission line is a waveguide.

16. The assembly of claim 11 wherein the slave unit is adapted to expand in response to the transmission of the energy thereto to produce the mechanical output.

17. The assembly of claim 11 wherein the slave unit comprises a member adapted to expand in response to the transmission of the energy thereto to produce a mechanical output in the form of linear motion.

18. The assembly of claim 17 wherein the member is machined to provide increased heat transfer surfaces to receive the energy.

19. The assembly of claim 1 wherein the slave unit comprises a bellows containing fluid that expands in response to the transmission of the energy thereto.

20. The assembly of claim 19 wherein the expansion of the fluid causes linear motion of the bellows to produce the mechanical output.

21. The assembly of claim 11 wherein the one position is the closed position of the valve and wherein the other position is the open position of the valve.

22. A method of actuating an electrical device, comprising the steps of transmitting a source of radiated energy over a waveguide to a slave unit, and connecting the slave unit to the device at a remote location from the energy source, and actuating the device by converting the energy to a mechanical output at the slave device.