Containment device and containment system for permeability

Abstract

A containment device for permeability measurements of a thermoplastic pipe wall is proposed. The containment device comprises a chamber wall (20) that can be mounted to a pipe wall and forms a closed containment chamber (25) when mounted to the pipe wall, wherein the chamber wall (20) is fluid-tight, at least one fastening element (38) for fixing the chamber wall hermetically to a pipe, and either at least one outlet (34) in the chamber wall (20) allowing the passage of air / gas from the containment chamber to the outside, having a connection that can be closed to at least one of a sensor, a sampling container, or a sensor fastening element on the chamber wall for attaching a sensor inside the containment chamber. Figure 1

Description

Title of the invention: Containment device and containment system for permeability technical field

[0001] The present invention relates to the field of pipes, in particular thermoplastic pipes, and the characterization of pipe permeability under operating conditions. More specifically, the present invention relates to a containment device and a containment system. STATE OF THE ART

[0002] In recent years, pipes or conduits made of thermoplastic materials have been installed to replace pipes. Thermoplastic materials include, but are not limited to, PE, PB, PEX, PERT, PER... or composite materials (pipe structure made of several materials) with different layers of functional materials (PEX, PERT, PVDF, Aluminium...).

[0003] Aging is a potential weakness of these thermoplastic materials compared to the stainless steel traditionally used in industrial installations. In particular, small gas molecules can diffuse or permeate through the structure of a porous plastic material by diffusion, even in the absence of mechanical failure. This diffusion can occur either at the pipe walls or through the joints between them.

[0004] PVC pipes are generally less prone to diffusion than PE (polyethylene) and PB (polybutylene) pipes. Since PVC is an amorphous polymer, this diffusion is lower than that associated with the semi-crystalline networks of PE and PB.

[0005] UV radiation and light exposure are a common cause of aging. In addition, certain fluids can also accelerate pipe aging. For example, chlorine used in water disinfection can cause PVC to swell, thereby accelerating its aging.

[0006] It would be useful to be able to know the mechanical condition of a pipe and / or fitting in a fluid network, in particular to be able to monitor the aging of thermoplastic-based installations transporting fluids such as hydrogen, CO2 with traces of hydrocarbons and ammonia, methanol, water, and more generally, all fluids. In particular, industrial applications often require that the condition of the networks be monitored for safety reasons.

[0007] One object of this disclosure is to provide a system and a method for determining the porosity and / or permeability of a pipe and / or fitting, particularly in relation to the aging of a thermoplastic pipe. Summary of the invention

[0008] To this end, the present invention provides a containment device for measuring the porosity and / or permeability of a thermoplastic pipe wall, comprising a chamber wall that can be mounted to a pipe wall and forms a closed containment chamber when mounted to a pipe wall, and at least one fastening element for fixing the chamber wall in a hermetic manner to a pipe. It provides either at least one outlet in the chamber wall allowing the passage of air / gas from the containment chamber to the outside, having a connection that can be closed to at least one sensor and / or a sampling container, or a sensor mounting element on the chamber wall for fixing a sensor inside the containment chamber. The chamber wall is fluid-tight.

[0009] The present invention proposes to characterize the porosity and / or permeability of a thermoplastic pipe wall, in particular for chemical components flowing through the pipe having the thermoplastic pipe wall.

[0010] The containment device has a containment wall that can be placed on a pipe wall to form a containment chamber. The containment chamber retains chemical components that have migrated out of the pipe wall. The chemical components can originate from the fluid flowing in the pipe or from the pipe wall itself.

[0011] The containment chamber is a closed containment chamber, allowing the measurement of porosity / permeability. Indeed, the density of the gas is so low that the relevant parameters cannot be detected in open air.

[0012] Porosity / permeability can be measured in different ways, for example, by chemical relaxation, etc.

[0013] In one aspect, the chamber wall is made of thermoplastic material, and at least one fastening element includes an electrofusion wire for welding the chamber wall to the thermoplastic pipe wall.

[0014] The containment device can be permanently placed on the pipe, for example by welding. This can be done during the installation of the pipe.

[0015] In another aspect, at least one fixing element is removable to allow the removable fixing of the chamber wall.

[0016] The containment device can be placed after the pipe installation, with the advantage that the chamber wall which is placed afterwards will not have undergone aging.

[0017] Whether the containment device is removable or not may also depend on the aging agent. For example, with UV radiation, the containment device can be placed after degradation.

[0018] The chamber wall can be made of a multilayer material with at least one layer being a fluid-tight layer or the chamber wall is made of a fluid-tight layer, the fluid-tight layer being a metallic layer.

[0019] The fluid-tight layer can be removable, to allow replacement of the layer if necessary.

[0020] At least one power supply wire may be provided for powering the electrofusion wire.

[0021] The present invention also proposes a detection system for porosity and / or permeability having at least one such containment device. The at least one containment device can be hermetically mounted on / to a pipe wall, the containment chamber being closed by the chamber wall and the pipe wall, and either a sensor is connected to the outlet or to the sensor mounting element in the containment chamber for detecting chemical elements, which, in operation, can detect chemical elements originating from the containment chamber, or a sample container for detecting chemical elements originating from the containment chamber.

[0022] In one aspect, the detection system may include a monitoring device to receive the detected data and deduce a porosity / permeability of the pipe wall, and deduce the aging of the pipe wall based on the porosity.

[0023] A calibration device can also be used, in particular to take into account the properties of the chamber wall.

[0024] A method for monitoring / diagnosing / characterizing / maintaining a pipe wall is also proposed. The method includes attaching such a containment device to a pipe wall, connecting at least one sensor and / or a sampling container to the outlet of the containment chamber.

[0025] The process may include electrofusion of the containment device to the pipe.

[0026] The method may include injecting material into the pipe wall.

[0027] The containment device can be used on any pipe such as an underground pipe (infrastructure), a pipe suspended in the air (industry), or a buried pipe.

[0028] The containment device does not rely on a leak from a seal. A key difference compared to prior art leak detection lies in the size of what is measured; it is not a major rupture but a small change in permeability. Indeed, with the containment chamber closed, it is It is possible to measure small changes over time, such as a change in density over time (flow / rate, not a fixed data point).

[0029] The difference with a leak is that a leak is localized, whereas permeability is generally a degradation throughout the pipe, although a degradation of permeability can present a risk of local failure that must be addressed. It should be noted that a porous material is generally more permeable. However, a material can be permeable without any porosity. Permeability and / or porosity can both present a localized risk of failure.

[0030] The chamber wall can be made of a different material or the same material as the pipe. If the containment device is permanently fixed to the pipe, an additional airtight wall is provided so that the potential aging of the chamber wall does not affect the measurements relating to the aged pipe material.

[0031] The containment device operates at both low and high pressures inside the pipe, although high pressure is more favorable to permeation. In terms of transported fluids, applications other than hydrogen could be used, for example ammonia, CO2, methanol, methane, heavy hydrocarbons, and water. DESCRIPTION OF THE DRAWINGS

[0032] Other features and advantages of the invention will become more apparent upon reading the description of several currently preferred embodiments, given solely by way of example, with reference to the accompanying drawings, in which:

[0033] [Fig. 1] shows a containment device mounted on a pipe and with a monitoring system according to one aspect of this disclosure,

[0034] [Fig.2] shows details of the containment device of the [Fig.1],

[0035] [Fig.3] shows details of the containment device of the [Fig.1],

[0036] [Fig.4] shows a containment device according to one aspect of the present disclosure,

[0037] [Fig. 5] shows a containment device with a sensor according to one aspect of the present disclosure,

[0038] [Fig.6] shows aging data based on permeability according to a another aspect of this disclosure. DETAILED DESCRIPTION

[0039] In the figures, identical parts are identified using the same reference numbers.

[0040] Fig. 1 shows a containment device 1 mounted on a pipe 2, and Fig. 2 shows details of the containment device. The pipe may, for example, be a pipe for / in a piping system for industrial installations, for example of a fluid gas.

[0041] The pipe or tube can be made of a single material and made of thermoplastic materials including, but not limited to, PE, PB, PEX, PERT, PER... or composite materials (pipe structure in several materials) with different layers of functional materials (PEX, PERT, PVDF,...).

[0042] The containment device 1 comprises a chamber wall 20, which is hermetically fixed to the pipe wall 10. The chamber wall 20 and the pipe wall 10 form a closed containment chamber 25.

[0043] An outlet 34 is provided in the chamber wall 20, to allow air to pass through the containment chamber, from the containment chamber to the outside.

[0044] In particular, a sensor 52 or a sampling container 55 can be connected to the output 34 via a sensor connector 50. A sampling or measurement system as described in [Fig. 5] can be connected. It is possible to connect more than one sensor and / or more than one sampling container.

[0045] If necessary, in particular for a containment device permanently attached to a pipe, a cap 39 can close the outlet, to avoid leaving a sensor in place and / or to adapt the sensor to the fluid flowing through the pipe ( [Fig.2]).

[0046] The sensor 52 is designed to detect chemical elements exiting the containment chamber. Different sensors can be used. For example, the sensor can measure the concentration of only certain specific chemical elements present in the fluid flowing through the pipe. Alternatively, the sensor can also characterize the chemical elements, for example, using a portable chromatography device.

[0047] Porosity / permeability can be measured in different ways, for example, by chemical relaxation, etc.

[0048] The chemical elements may originate from the fluid transported in the pipe, or from the thermoplastic materials of the pipe wall 10 itself, having migrated through the pipe wall 10. As the containment chamber 25 is closed, the chemical elements are confined in the chamber and can only exit through the outlet 34.

[0049] In the example of [Fig. 1], the chamber wall 20 is made of thermoplastic material. The chamber wall 20 has free ends 28 provided with electrofusion wires 38 integrated inside, for welding the free ends 28 of the chamber wall 20 to the pipe wall 10 by electrofusion.

[0050] A power supply wire 90 is provided for supplying power to the electrofusion wire. The power supply wire 90 connects the electrofusion wire to the electrical system that supplies power for electrofusion and can also be seen in [Fig. 3].

[0051] The electrofusion wire 38 can be a helical spring which, during the welding operation, heats and melts the material surrounding the electrofusion wire 38.

[0052] It should be noted that the containment device 1 can be positioned on a sector of the circumference of the pipe wall 10. In this configuration, the chamber wall 20 is then only part of a cylinder, and the electrofusion wire 38 preferably extends over the entire contact surface between the chamber wall 20 and the pipe 2.

[0053] The chamber wall is provided with a fluid-air-gas impermeable layer 48. This layer 48 can be chosen according to the chemical components under study.

[0054] In [Fig. 1], the chamber wall 20 is welded to the pipe. However, it is possible to mount the containment device removably on the pipe. This is illustrated in [Fig. 4]. In this example, instead of electrofusion welding, a pipe clamp is provided as a fastening element, together with a standard O-ring 139. The chamber wall 20 is held firmly onto the pipe 2 by means of the pipe clamp 138. The fastening element has a sealing gasket at the free ends 28 of the wall for a tight seal of the containment device. Advantageously, this allows measurement campaigns to be carried out on a regular basis and at a chosen location on the pipe, for example, to check the condition of the pipe or according to a schedule defined by preventive maintenance tools.

[0055] In the illustrated examples, the sealing layer 48 is provided in the chamber wall 20, somewhere between the inner surface and the outer surface of the chamber wall 20. This is not limiting and the sealing layer 48 can be positioned anywhere, from the inner surface to the outer surface of the chamber wall 20.

[0056] In the example of [Fig. 1], the sealing layer 48 is integrated into the thermoplastic material of the wall. It is also possible to position the sealing layer 48 in a removable manner. Advantageously, this allows the sealing layer 48 to be changed or adapted according to the chemical substances flowing through the pipe that could potentially migrate through the pipe wall 10.

[0057] In this example, the sensor 52 is fixed to the outside of the containment device. It is possible to position the sensor 52 inside the containment device, via a sensor mounting element attached to the chamber wall 20.

[0058] Fig. 5 shows an example in which the outlet 34 is connected to a vacuum pump 57, to draw air or fluid from the containment chamber 25 to the sensor 52.

[0059] It is also possible to connect to a sampling bottle 55, which will be sent to a characterization laboratory for further analysis or reference. This is shown in [Fig. 4], but this is only one option; there is no obligation to connect both a sensor 52 and a sampling bottle, and there could be other connections to sampling containers or sensors 52, with or without the vacuum pump 57.

[0060] A monitoring system 80 can be provided to monitor the pipe and optionally operate the sensor 50 to acquire permeability data.

[0061] A microcontroller 60 can be positioned on the containment device 1 or remotely. The microcontroller 60 can include a data acquisition module, memory, and a communication module with connection capabilities for sending data to a monitoring module 70 of a monitoring system 80. The microcontroller can also control the sensor 50 or any device such as a pump, if necessary.

[0062] The monitoring system 80, as illustrated in [Fig.1], includes the monitoring module 70 in communication with the microcontroller 60. The microcontroller 60 can be connected to the monitoring module 70 by known means of communication such as an Ethernet or PoE (Power Over Ethernet) cable, a coaxial cable, a fiber optic cable, an Internet modem, Wi-Fi, a 3G / 4G / 5G connection, Bluetooth, LiFi, infrared, an SPI link, a DSL cable or a USB cable.

[0063] The monitoring system 80 can activate at least one display mode to produce at least one display indicating information on the current permeability values ​​and / or the network status, and an alert mode to produce an alert on the current values ​​and / or the network status. The monitoring system 80 can also activate a control mode to send control signals to the microcontroller 60 to operate the sensor 50.

[0064] A fluid distribution network can therefore include a plurality of containment devices 1, with a plurality of microcontrollers 60, connected to the monitoring system 80, for example via Bluetooth managed by a communication module.

[0065] An interface module can be provided to manage physical interactions with a user. The interface module can also manage a monitor system screen 80, control indicator lights and wake up the microcontroller 60 when display buttons on the screen are pressed.

[0066] In a non-limiting example, the plurality of microcontrollers 60 is connected to at least one aggregator in order to collect the data acquired by the microcontrollers 60. One or more aggregators may collect data from a part of the fluid distribution network. The data collected by one or more aggregators is transmitted to a monitoring module 70.

[0067] More specifically, the monitoring system 80 is adapted to receive data on chemical elements from one or more sensors 50 connected to a respective plurality of containment devices, and to characterize, at least in part, the permeability of the mechanical states of the pipes. Subsequently, it is possible to deduce potential limits to pipe rupture or aging.

[0068] This allows us to assess the current condition of the pipe and / or fitting.

[0069] Examples of aging / porosity / permeability data are shown in [Fig. 6]. The graph shows the evolution of permeability (expressed in cm³ / m².d) with age. Temperature is shown since it affects permeability. The more advanced the aging, the higher the permeability. The evolution of permeability can be evaluated, particularly when a pipe supplier provides the permeability value as a function of temperature and pressure for the new pipe as a reference or by taking a baseline measurement. Over time, the permeability evolution can be derived and extrapolated, thus providing useful data for predictive maintenance models.

[0070] In addition, the absolute flow rate must be compared to the operator's standards or specifications to assess acceptability.

[0071] It should be noted that permeability / porosity depends on the material, the age of the material, the thickness of the material, and even the manufacturing process of the pipe. Therefore, what is important is to estimate the gas or air flow over a given period of time and to deduce a total loss rate over the entire length of the pipe. This value is considered acceptable with reference to specific standards or requirements.

[0072] The containment device can be placed after the pipe installation, with the advantage that the chamber wall placed afterwards will not have undergone aging.

[0073] Calibration can be performed when the containment device is fixed to the pipe wall and the containment chamber is formed.

[0074] In addition, the monitoring system 80 can give an indication for predictive maintenance, based on historical records of collected data.

[0075] The containment device can therefore be placed anywhere on a pipe installation, i.e. on a pipe wall only or on a fitting.

[0076] For example, it is also possible to measure the presence or absence of a microcrack, if desired, at a location where the microcrack is expected (with the additional possibility of using the sleeve to repair the crack, for example by injecting a repair agent - how). In the case of using the If a chamber is placed on a surface where cracking is suspected, it can indeed be used as a containment device into which a resin or any suitable product can be injected.

[0077] The preceding description of preferred embodiments of the disclosure has been provided for illustrative and descriptive purposes only. It is not intended to be exhaustive or to limit the invention to the precise form disclosed, and modifications and variations are possible in light of the above teachings or may be acquired from the practice of the invention. The embodiment has been chosen and described to explain the principles of the invention and its practical application to enable a person skilled in the art to use the invention in various embodiments suitable for the particular intended use. It is anticipated that the scope of the invention will be defined by the accompanying claims and their equivalents.

Claims

Demands

1. Containment device (1) for permeability measurements of a thermoplastic pipe wall, comprising a chamber wall (20) that can be mounted to a pipe wall and forms a closed containment chamber (25) when mounted to a pipe wall, wherein the chamber wall (20) is a fluid-tight wall, at least one fastening element (38; 138) for fixing the chamber wall hermetically to a pipe, and either A: at least one outlet (34) in the chamber wall (20) allowing the passage of air / gas from the containment chamber to the outside, having a connection that can be closed (50) to at least one of a sensor and / or a sampling container, or B: a sensor fastening element on the chamber wall for attaching a sensor inside the containment chamber.

2. Containment device according to claim 1, wherein the chamber wall (20) is made of thermoplastic material, and at least one fastening element comprises an electrofusion wire (38) for welding the chamber wall to the thermoplastic pipe wall.

3. Containment device according to claim 1, wherein at least one fixing element is removable to allow removable fixing of the chamber wall.

4. Containment device according to claims 1 to 3, wherein the chamber wall (20) is made of a multilayer material with at least one layer (48) being a fluid-tight layer or wherein the chamber wall is made of a fluid-tight layer, the fluid-tight layer being a metallic layer.

5. Containment device according to claim 3, wherein the fluid-tight layer (48) is removable.

6. A permeability detection system having at least one containment device (1) according to any one of the preceding claims, wherein the at least one containment device can be mounted on / to a pipe wall, with the containment chamber (25) being closed by the chamber wall and the pipe wall, and either a sensor (52) connected to the outlet or to the sensor attachment element in the containment chamber for detecting chemical elements, which, in operation, can detect chemical elements from the containment chamber, or a sampling container (55) for the detection of chemical elements from the containment chamber.

7. A detection system according to claim 6, comprising a monitoring device for receiving detected data and inferring porosity / permeability of the pipe wall, and inferring aging of the pipe wall based on porosity.

8. Detection system according to claim 6, comprising a calibration device.

Images