Patent Description:
Assemblies exist that can be connected to fluid-transporting pipelines. Such assemblies provide a connection point to pipelines to allow a direction change, diameter change, purging or other use. Such assemblies are known as purge tees, tapping tees, electrofusion purge tees and the like. Purge tees, as one example, are typically formed from the same material as the pipe and have standard cap fittings creating a fluid tight seal. Purge tees and their respective components including standard caps need to comply with the most stringent gas and water industry specifications GIS PL2:<NUM>, BS EN <NUM>-<NUM>, BS EN12201-<NUM>, additionally requiring WRAS approval for the materials used. In use, a purge tee is a convenient way of connecting pipes and/or purging fluid from the pipe for pressure testing, for example. Typically, a tapping tee is an integral part enabling the tap to cut through the main pipe once the purge tee is connected. The tap then acts as a valve and, in the open position, permits gas from the main pipe to be channelled into the purge tee area. This offers the opportunity to measure the contents/fluid inside the purge tee. In any of the preferred uses of the purge tee it is important that there are no protrusions or components that inhibit performance or function in anyway. Examples of companies that make such assemblies include Radius Systems and Fusion Group.

Standard caps are used with the above-described assemblies as a way of sealing any open sections when not required for use and creating a fluid-tight seal so as to not impede the normal functioning of the pipe.

<CIT> discloses a nozzle cap for a fire hydrant and a method for manufacturing a nozzle cap to detect leaks in a fluid system.

<CIT> discloses an element provided in particular as a closure element or fastening element for inserting into a bore in a component, such as into a bore in an engine, a valve block, a hydraulic unit or a container.

Disclosed herein is a cap for fitting to a pipe end to detect one or more conditions within a pipe, the cap comprising: a housing comprising a first opening at a first end thereof, the opening comprising a fitting means arranged to cooperate with a corresponding fitting means of the pipe end to secure the cap to the pipe end; and a sensor, the sensor being configured to detect one or more conditions within a pipe, wherein, when the cap is fitted to a pipe end, the sensor is arranged to detect one or more conditions within a pipe comprising the pipe end.

Optionally, the pipe end is one end of a pipe tee, and optionally wherein the pipe tee is a purge tee.

The fitting means of the first opening is a screw thread located on an internal wall of the housing, and the corresponding fitting means of the pipe end is a corresponding screw thread on an external wall of the pipe end.

Optionally, the cap is arranged to create a fluid-tight seal with the pipe end.

Optionally, the sensor is located within the housing.

Optionally, the cap comprises a second opening at a second end thereof, and a sensor module including the sensor, the second opening being arranged to receive the sensor module.

Optionally, the sensor module is removable.

Optionally, the sensor module comprises a sensor module fitting means arranged to cooperate with a corresponding second opening fitting means of the second opening to secure the sensor module within the second opening.

Optionally, the sensor module fitting means comprises a screw thread located on an external wall of the sensor module, and wherein the corresponding second opening fitting means comprises a corresponding screw thread on an internal wall of the second opening.

Optionally, the sensor module is arranged to create a fluid-tight seal with the second opening.

Optionally, the sensor module comprises a first end and a second end and wherein, when the sensor module is received into the second opening, the first end is in communication with the second opening and the second end is in communication with an exterior of the cap. Optionally, the sensor is located at the first end of the sensor module.

Optionally, the first end comprises a recessed portion, the sensor being located within the recessed portion.

Optionally, the first end protrudes into an interior of the cap but does not extend beyond the cap.

Optionally, the sensor is integral with the sensor module.

The cap comprises an electrical connection point for the sensor on an external wall of the cap.

Optionally, the second end of the sensor module comprises the electrical connection point for the sensor.

Optionally, a diameter of the second opening is less than a diameter of the first opening.

Optionally, the sensor is a piezoresistive sensor.

Optionally, the cap is formed of a polymer such as pipe grade polyethylene, low density polyethylene or high density polyethylene.

Optionally, the one or more conditions comprises at least one of a force, pressure or temperature.

Also disclosed herein is a system for detecting a one or more conditions within a pipe, the system comprising: the cap including any of the above features; and a processing unit electrically connected to the sensor of the cap via the electrical connection point, wherein the processor is arranged to determine one or more conditions within the pipe.

Optionally, the processing unit further comprises a processor.

Optionally, the processing unit further comprises a power source to provide electrical power to the processing unit and the sensor.

Optionally, the processing unit further comprises a wireless communication means for transmitting a signal from the sensor.

Optionally, the cap comprises the processing unit.

Also disclosed herein is a method for detecting a change in one or more conditions within a pipe using the system having any of the above features, the method comprising: detecting, based on a first signal from the sensor, a first reading relating to a condition within the pipe at a first time; detecting, based on a second signal from the sensor, a second reading relating to the condition within the pipe at a second time; and determining, by the processing unit, a change in the condition based on a difference between the first reading and the second reading.

Examples of the technology described herein are provided with reference to the below-described figures:.

Like numerals are used to describe like components throughout.

<FIG> illustrates a cap <NUM> for fitting to a pipe end. Such a pipe end may be part of a pipe that transports fluid around a pipeline, for example liquid or gas or a mixture thereof. The fluid may be natural gas or hydrogen, for example. Such a pipe includes pipelines, pipe fittings, utility pipelines, energy and power pipelines, water pipes, gas pipes, heating pipes, district heating pipes and oil pipelines, for example.

The cap <NUM> comprises a housing having a first opening <NUM> at a first end thereof and, optionally, a second opening <NUM> at a second end thereof. As shown in <FIG>, the second end is opposite the first end. The first opening <NUM> is also shown having a fitting means <NUM>. In the example of <FIG>, the fitting means <NUM> is a screw thread located on an internal wall of the cap <NUM>. As is shown, the first opening <NUM> is substantially circular and the screw thread extends along the internal wall forming a substantially cylindrical threaded section. The fitting means <NUM> is arranged to interact and correspond with a fitting means of the pipe end (not shown) in order to secure the cap <NUM> to the pipe end and create a fluid-tight seal. In this case, the pipe end has a corresponding threaded section to interact with the fitting means <NUM>, such that the cap <NUM> may be screwed onto the pipe end. Such a fluid-tight seal may be achieved via interaction with of the two fitting means themselves, however additional components may be provided to ensure a fluid-tight seal. An example additional component is a rubber O-ring, for example, however other components may be used as would be understood.

The fitting means <NUM> of the cap <NUM> may be substantially the same as existing caps already in use for sealing pipe ends. Such a fitting means <NUM> therefore allows retrofit to existing pipe ends, which already have threaded sections, without requiring any alteration to the pipe ends themselves. As such, the cap <NUM> described herein may be easily retrofitted to existing pipelines.

The cap <NUM> includes a wall <NUM>. The wall may have a variety of thicknesses and may correspond to the wall thickness of standard caps. As an example, the wall thickness may be at least <NUM>, and may vary across the profile of the cap.

The second opening <NUM> of the cap <NUM> may also be substantially circular and, like the first opening <NUM>, may include a fitting means extending along an internal wall of the second opening <NUM> forming a substantially cylindrical threaded section. This fitting means is arranged to interact and correspond with a fitting means of a sensor module <NUM> (see <FIG>). The diameter of the second opening <NUM> may be less than the diameter of the first opening <NUM>.

To manufacture the cap <NUM>, any material and any manufacturing technique can be used. For example, the cap <NUM> may be injection moulded with polyethylene as the polymer. Particularly, pipe grade polyethylene may be used. Alternatively, low density or high density polyethylene may be used. While the cap <NUM> may be moulded as a single component, the cap <NUM> may alternatively be produced in two component parts. In the case of two component parts, the fitting means of the second opening <NUM> may be formed separately as part <NUM> shown in <FIG>. The part <NUM> may then be fitting to the second opening <NUM> using an adhesive, for example, or any other method such as a heat or sonic weld, knurl and groove, snap fit, or friction fit, with or without additional sealing. Indeed any fitting method may be used as long as at least a fluid-tight seal, and preferably a hermetic seal, in provided.

The dimensions and size of the cap <NUM> can vary. In one example, the first opening <NUM> may be shaped and sized to fit a <NUM> purge tee or tapping tee orifice. The same sized cap <NUM> may also be used for other sized orifices, such as a <NUM> tee orifice, by providing a standard reducer component to reduce the size of the tee orifice down to the dimensions of the first opening <NUM>, as would be understood. The reducer component may, for example, be fittable at one end to a <NUM> tee orifice and provide, at another end of the reducer component, a <NUM> orifice for fitting the cap <NUM>. In other examples, the shape and size of the first opening <NUM> can be determined based on the shape and size of a target pipe end. While a reduction in tee orifice size has been discussed, the opposite may also be provided, such as an increaser component to increase the size of the tee orifice up to the size of the first opening <NUM>.

Looking now at <FIG>, the sensor module <NUM> comprises a fitting means <NUM> arranged to interact and correspond with the fitting means of the second opening <NUM>. As shown in <FIG>, and particularly in cross section <NUM>, the sensor module <NUM> may be substantially cylindrical and the fitting means <NUM> may be thread extending along at least part of an external wall of the sensor module <NUM>. In this embodiment, the fitting means <NUM> of the sensor module <NUM> interacts with the threaded section of the second opening <NUM> allowing the sensor module <NUM> to be screwed into the second opening. This screw fixing of the sensor module <NUM> to the second opening <NUM> allows the sensor module <NUM> to be removably attached to the cap <NUM>. This is beneficial in that the sensor module <NUM> may be changed without requiring a new or different cap <NUM>. The fixing of the sensor module <NUM> to the cap <NUM> provides a fluid-tight seal and, as would be understood, additional compressible components may be provided to ensure that the seal is fluid-tight. For example, an O-ring, gasket or other components may be provided, as would be understood. An example location for additional sealing components is between the fitting means <NUM> and an optional module head, integral with the sensor module <NUM>, that provides a sealing shoulder <NUM> between the fitting means <NUM> and the module head. An O-ring provided around the sealing shoulder <NUM> can be formed from rubber such as Nitrile rubber, Viton or silicon.

Although a screw fitting means has been described, any fitting method may be used to secure the sensor module <NUM> into the second opening <NUM> in a removable or fixed manner. For example, an adhesive may be used instead of threaded sections.

The sensor module <NUM> includes a sensor (not shown) at a first end <NUM> thereof. The sensor may be any type of sensor that is able to detect a condition within the pipe, such as a pressure, force or temperature, and may be a pressure transducer. The sensor may be attached to the first end <NUM> in any suitable manner. For example, the first end <NUM> may include a recessed portion (see the cross section in <FIG>) within which the sensor can be located. The recessed portion may include a raised perimeter to aid placement and securement of the sensor, as shown in <FIG>.

In the case of the sensor being a pressure sensor, the sensor may comprise piezoresistive material such as the pressure-sensitive sensor provided by HP1 Technologies Ltd or Microsensor. For example, the sensor may be formed of a plurality of layers to form a pair of electrodes connected by a piezoresistive ink spot. The ink spot may be laid across the electrodes or sandwiched therebetween. As would be understood, the resistance of the ink spot changes in response to a pressure or force experienced by the ink spot, thereby allowing a resistance change across the ink spot to be measured via connection of the two electrodes to processing circuitry. The change in resistance allows a change in pressure/force to be derived therefrom.

The sensor module <NUM> also includes a second end opposite the first end <NUM>, the second end includes an electrical connection point <NUM>. Terminals of the sensor run through the interior of the sensor module <NUM> from the first end <NUM> to the second end, to provide terminal connections at the electrical connection point <NUM>. The electrical connection point therefore <NUM> provides an area for connecting the sensor to other circuitry via wires/cables. The electrical connection point <NUM> may provide one or more physical and electrical connection points for cables, or cables may simply extend out from electrical connection point <NUM> and be directly connected to the sensor through the interior of the sensor module <NUM>. Optionally, the electrical connection point <NUM> include one or more additional materials for the purposes of shielding the electrical components/contacts for compliance with the necessary safety regulations for pipelines. Shielding may also be provided over the sensor itself as is necessary.

When the sensor module <NUM> is fitted to the cap <NUM>, the first end <NUM> is in communication with and exposed to the interior of the cap <NUM>, and the second end is in communication with and exposed to the environment external to the cap <NUM>. In this manner, when the cap <NUM> is fitted to a pipe end, the sensor is in communication with and exposed to the interior of the pipe. Preferably, the first end <NUM> and sensor are sized such that the first end <NUM> and sensor remain confined within the geometry of the cap. In other words, the first end <NUM> and sensor protrude into the interior of the cap <NUM> but do not extend beyond the cap <NUM> (i.e. past the first opening <NUM>).

Although only one sensor has been described at the first end <NUM>, a plurality of sensors may be provided. Such sensors may be of the same type (e.g. pressure) or could be of different types (e.g. pressure and temperature). The capabilities of the sensor and the condition to be sensed can be determined based on the specifics of the pipe in question, and indeed a plurality of different sensors may be used to detect different conditions in the same pipe.

<FIG> shows a cross section <NUM> of cap <NUM> with sensor module <NUM>. Cap <NUM> and sensor module <NUM>, as mentioned previously, are at least fluid-tight and preferably hermetically sealed to the relevant compliant standards. This can be achieved via the corresponding fitting means themselves, or additional components could be added to work in conjunction with the fitting means, as previously mentioned.

<FIG> shows a cover <NUM> that may be placed at the base of the cap <NUM>, where the first opening <NUM> is located, to protect the exposed sensor at the first end <NUM> of the sensor module <NUM> during transit or storage. The cover <NUM> preferably has a wider diameter than either the reducer component or pipe tee orifice so that it is not possible to fit the cap <NUM> without removing the cover <NUM> first. Optionally, a second or even a third cover can be used for protecting the electrical connection point <NUM> and/or for directly protecting the sensor located at the first end <NUM>. The optional additional covers are not illustrated in <FIG>.

<FIG> shows an example pipe system <NUM> having a pipe <NUM> which transports fluid, an example pipe tee <NUM> (in this case a purge tee) and an example standard cap <NUM> as is known in the art. As shown, the cap <NUM> described herein can be attached to any point of the pipe tee where a standard cap could instead be fitted. Example companies that make purge tees and similar fitments which include standard caps are Radius Systems and Fusion.

The fluid being transported through the section of pipe <NUM> at the purge tee point fills the cavity of the purge tee <NUM>. The benefit of introducing the cap <NUM> at the purge tee or tapping tee point is that the condition of the fluid at this point has the same readings, such as pressure values, as the fluid in the pipe <NUM> in that section at any given time. Therefore, there is no requirement for a sensor to be inserted into the pipe <NUM> itself.

<FIG>shows a system <NUM> comprising the cap <NUM>, including the sensor module <NUM>, and a processing unit <NUM>. The cap <NUM> shown in <FIG> is located in situ and fixed to a pipe end of a pipe tee <NUM> (in this case, a purge tee). When fixed, the sensor of the sensor module <NUM> is exposed to the interior of the pipe tee <NUM> which is connected to a section of the pipe <NUM>. The cap <NUM> is at least fluid-sealed, and ideally hermetically sealed, to the pipe tee <NUM> by the fitting means <NUM> previously described (and optionally compression of an O-ring located at the pipe end opening).

The sensor of the sensor module <NUM> can be connected, via the electrical connection point <NUM>, to a cable connector <NUM> that connects one end of an electrical cable <NUM> between the sensor module <NUM> of the cap <NUM> and other elements of a condition detecting system. To complete the electrical circuit, the other end of the electrical cable <NUM> can be connected to the processing unit <NUM> which may include a plurality of equipment and devices such as one or more of : a power source <NUM>, a CPU, hub or port <NUM>, and a wireless communication means <NUM> to interpret signals (A/D converter) received from the sensor and to transmit signals and/or data remotely, or receive signals and/or data. Combinations of all or individually <NUM>, <NUM> and <NUM> can be housed in a surface box near the location of the cap <NUM>. This system allows the sensor module <NUM> of the cap <NUM> to detect and transmit signal data regarding the condition in the pipe.

While the elements <NUM>, <NUM> and <NUM> have been described as separate from the cap <NUM> and sensor module <NUM>, these elements could instead be part of the cap <NUM> or sensor module <NUM> and housed therein or integral therewith. This may be by virtual of a separate compartment within or joined to the cap <NUM> or sensor module <NUM> to house these elements.

The content of the pipe can vary (e.g. gas or liquid), as can the sensing capability and type of sensor, which may include multiple sensors or combinations of sensors. Preferably, the sensor includes at least one sensor being a pressure sensor and having piezoresistive material.

Installation of the cap <NUM> onto a pipe end can be performed in the same way as installation of a standard cap. If covers <NUM> are used, the cover should be removed prior to installation. Following initial installation, it will then depend upon the installing company's preferred method to connect the sensor module <NUM> of the cap <NUM> to power and third-party devices enabling data transfer. It would be recommended to have cleared a path between, for example, the purge tee assembly and the ground surface which would have been required on installation of the purge tee. The cleared pathway allows for the introduction of the cable <NUM> to be connected to the sensor module <NUM>. Optionally, protective piping, additional seals and/or surface boxes can be introduced in accordance with the company's preferred protocol and compliance criteria. Optionally, the external profile of the cap <NUM> or sensor module <NUM> may also provide means for fitment or connection to such protective piping with the introduction of extensions on the outer profile of the cap.

The other end of the cable <NUM> can then be connected to the third-party equipment enabling data transfer and use. Optionally, data can be received which may include any remedial actions that need to be conducted based on the data/signal output of the sensing elements in the sensor.

The use of the cap <NUM> and sensor module <NUM> has various benefits. One benefit is the ability to readily and easily retrofit a device to detect the current, or changes in, conditions within a pipe. Example conditions are force, pressure and temperature, and the correct sensor or sensors for detecting such a condition is chosen. Other condition changes may also be measured. One method would be to detect a first reading relating to a condition (e.g. pressure) at a first time, detect a second reading relating to the condition at a second time, and, using a processor, determine a change based on the different between the first reading and the second reading. In the example of the condition being pressure, this method determines the pressure change within the pipe over time.

Other uses are envisioned, and the cap <NUM>, sensor module <NUM> and system described herein may be used to monitor the conditions within a pipe in real-time by virtue of sending a constant or periodic transmission of sensor data to a third party, before or after analysis by a processing unit such as the processing unit <NUM>. Such signals may be monitored, recorded or measured to enable a real-time determination of conditions within a pipe. A plurality of such caps <NUM> and sensor modules <NUM> or systems may be deployed throughout a pipeline network to provide a "smart" pipeline in which the condition of all or specific pipe sections is known in real-time.

Claim 1:
A cap (<NUM>) for fitting to a pipe end to detect one or more conditions within a pipe (<NUM>) comprising the pipe end,
the cap comprising:
a housing comprising a first opening (<NUM>) at a first end thereof, the opening comprising a fitting means (<NUM>) arranged to cooperate with a corresponding fitting means of the pipe end to secure the cap to the pipe end; and
a sensor, the sensor being configured to detect one or more conditions within the pipe,
wherein, when the cap is fitted to the pipe end, the sensor is arranged to detect one or more conditions within the pipe,
wherein the fitting means of the first opening is a screw thread located on an internal wall of the housing, and wherein the corresponding fitting means of the pipe end is a corresponding screw thread on an external wall of the pipe end,
characterised in that
the cap comprises an electrical connection point for the sensor on an external wall of the cap.