GB2450621A

GB2450621A - Camera with inflatable support

Info

Publication number: GB2450621A
Application number: GB0811669A
Authority: GB
Inventors: Andrew Harrison; Nicholas Stephen Robinson
Original assignee: STEVE VICK INTERNAT Ltd
Current assignee: STEVE VICK INTERNAT Ltd
Priority date: 2007-06-25
Filing date: 2008-06-25
Publication date: 2008-12-31
Also published as: GB0712322D0; GB0811669D0

Abstract

A camera unit 12 attached to a line 22 has an inflatable support structure, preferably a collar 20, inflation of which tends to raise the camera. When this is deflated, the unit can be passed through a small opening, e.g. an angled guide tube 34, into a pipe 30 such as a gas main. It can be manoeuvred along the pipe 30 by means of the line 22, which preferably incorporates an inflation line (24, figure 2) and an optical data line (26, figure 2). Visual data from the camera may be passed to the exterior via the optical data line (26, figure 2).

Description

CAMERA ASSEMBLY AND USE THEREOF

The present invention relates to a camera assembly and the use thereof, particularly for the visual monitoring of remote and/or difficulty accessible locations such as the interiors of cavities. It is particularly concerned with monitoring within pipes, especially gas pipes.

It is known to use a camera to monitor a gas main prior to work being carried out on it. Cameras can be used for purposes such as to locate a blockage, highlight damage, confirm or detect the ingress of water, and locate structural features such as off-takes and back feeds. For example, when an old steel main is to be refurbished by the insertion of a polyethylene(PE) pipe, the old pipe may first be checked by means of a camera, to see if there are any potential hazards that might cause the PE pipe to become stuck or damaged.

For all such purposes, it is important that the camera should obtain a reliable view of the interior of the main.

It is desirable to achieve this with the minimum disruption of the main. It is often possible to insert a small camera through a small gland that is attached to the top of the main. This is quite easy to achieve, and involves relatively little disruption or digging. This is satisfactory for a relatively small main. However, if a small camera is passed into a large main, it will generally end up on or near the bottom of the main. Its view then tends to be unclear, particularly as regards the upper reaches of the main. Furthermore, as the camera is pushed along the main, its orientation and position are likely to vary uncontrollably.

The current solution to this problem is to use a IS large camera that can run along a "track" inserted into the main. However, this requires major excavation of the main, with a section of the main being cut out, to allow a special end cap to be fitted. Clearly, this becomes a major operation, with much inconvenience and expense.

According to the present invention in a first aspect, there is provided a camera assembly comprising a camera unit and a support structure for it, wherein the support structure comprises an inflatable member whose inflation tends to raise the camera. The inflatable member may be an inflatable collar that surrounds the camera unit. Usually the inflation of the inflatable member is controllable remotely, e.g. by means of an inflation line. The output of the camera may be viewable remotely, e.g. via a camera data line (fibre-optic or cable for a signal from an electronic camera unit).

Conveniently, the camera data line and inflation line are integrated into a single line. This may have sufficient rigidity for it to be used to push the camera assembly into and along a cavity such as a gas main.

In another aspect the invention relates to the use of such a camera assembly for monitoring within a pipe, comprising providing an opening in the wall of the pipe (preferably with a gland seal), passing the camera assembly into the pipe through the opening, with the inflatable member in a non-inflated (or partially inflated) state; and subsequently increasing the degree of inflation of the inflatable member. The assembly may be moved along the main, before or after inflation, by pushing or pulling on a line attached to it.

An embodiment will now be described in greater detail with reference to the accompanying drawings in which: Fig 1 is a schematic view of a gas main into which a camera assembly according to a first embodiment of the invent ion has been inserted, and Fig 2 is a more detailed view of the camera assembly within the pipe.

A camera assembly 10 includes a camera unit 12.

This has an elongate cylindrical body 14 coupled at its front end, to a camera head 16. The cylindrical body 14 is surrounded by an inflatable collar or membrane 20. In the figures, this is shown in an inflated state. The cylindrical body is coupled at its rear end to a control line 22. As can be seen more clearly in Fig 2 this contains an inflation line 24 and an optical date line 26. The inflation line communicates with the interior of the inflatable collar 20. The optical data line 26 is coupled to the camera head 16.

The camera assembly 10 is shown located within a gas main 30. The main 30 has a "standard drilling equipment" 32 at an upper region. The "standard drilling equipment" 32 has a base 33a which is fast with the main 30 and has an integral valve, and a removable cap 33b. An angled guide tube 34 has an internal rubber gland. The control line 22 is passed through the tube 34, the gland forming a gas-tight seal, and connected to the camera assembly.

The tube 34 is attached to the base 33a, the integral valve is opened, and the camera assembly is passed into the main.

Outside the main 30, the control line 22 extends to a control area 36. Here there are (schematically shown) a driving unit 38 for urging the control line 22 further into or out of the gas main, an inflation unit (ItJ) 40 for controlling the inflation of the inflatable sleeve 20 via the inflation line 24; and a viewing unit (VU) 42, coupled to the optical data line 26 for viewing the output from the camera unit 12.

When the camera assembly is to be passed into (or removed from) the gas main 30, the inflatable collar is in its fully deflated state. The assembly can then pass easily through the drilling equipment 32. Once the assembly 10 is within the gas main 30, the sleeve can be inflated, using the inflation unit 40.

If the gas main is "live", containing inflammable gas, then clearly it is desirable that the inflation should use a "safe" gas such as nitrogen, in case any of the inflation gas leaks into the gas main. As shown, the degree of inflation is chosen so that the camera unit 12 is raised to a central region of the main, so that it can provide reliable visual data. The illustrated assembly may be suitable for use in low and medium pressure gas mains, with internal diameters in the range 6 to 48 inches (15 to 120 cm).

The illustrated collar is ellipsoidal when inflated.

The weight of the control line 22, and tension therein, acting at the rear counteract the weight of the camera unit 12 projecting from the front. The control line can be manoeuvred to adjust the attitude of the assembly.

Claims

Claims 1. A camera assembly comprising a camera unit and a support

structure for it, wherein the support structure comprises an inflatable member whose inflation tends to raise the camera.
2. A camera assembly according to claim 1 wherein the inflatable member is an inflatable collar that surrounds the camera unit.
3. A camera assembly according to claim 1 or claim 2 including an inflation line by means of which the inflation of the inflatable member is controllable remotely.
4. A camera assembly according to any preceding claim including a camera data line whereby the output of the camera is viewable remotely.
5. A camera assembly according to claim 3 or claim 4 wherein the camera data line and/or inflation line has sufficient rigidity for it to be used to push the camera assembly into and along a cavity.
6. A camera assembly substantially as herein described with reference to and as illustrated in the accompanying drawings.
7. A method of monitoring within a pipe, comprising providing an opening in the wall of the pipe, passing a camera assembly according to any preceding claim into the pipe through the opening, with the inflatable member in a non-inflated (or partially inflated) state; and subsequently increasing the degree of inflation of the

inflatable member.
8. A method according to claim 7 wherein the assembly is moved along the pipe, before or after inflation, by pushing or pulling on a line attached to it.
9. A method according to claim 7 or claim 8 wherein the pipe contains inflammable gas, and the inflatable member is inflated with a gas that does not support combustion.
10. A method of monitoring within a pipe substantially as herein described with reference to the accompanying drawings.