This relates to a containment integrity sensor device, which may be referred to as a gasket sensor, a wear sensor or a combination thereof herein. In particular, the wear sensor may be a compressible elastic displacement sensor or wear sensor, to be attached to a component of equipment or a structure for determining status and sensing one or more changes occurring at that component, such as alignment, gap, unloading, creep, wear, disintegration and failure. The sensor is sealed so that it may be operated in either hazardous or non-hazardous environments and is compatible with liquids, temperature, vibration and other environmental conditions.
Sensors are used to determine and monitor status and conditions of equipment and the environment at that equipment. For example, a sensor may be used to monitor temperature, humidity, atmosphere at an environment or other ambient conditions. Other sensors are used to monitor physical parameters of equipment, and the status of the equipment itself, including determining strain, vibration, and development of cracking.
Sensors also may be used to log data. Powers et al. in U.S. Pat. No. 5,381,136 (1995) describe a remote logger unit for monitoring a variety of operating parameters along a fluids distribution or transmission system. An RF link is activated by which a logger unit alerts a central controller when predetermined operating limits are exceeded. Farther logger units transmit data via closer logger units in daisy chain fashion.
Arms in U.S. Pat. No. 6,588,282 (2003) describes peak strain linear displacement sensor for monitoring strain in structures. The device records data and can report strain history for the structure to which it is attached. A displacement sensor is constrained so that it shows maximum movement in one direction resulting in deformation of the structure to which it is attached.
Hamel et al. in U.S. Pat. No. 7,081,693 (2006) and U.S. Pat. No. 7,170,201 (2007) describe devices for powering a load by harvesting energy as electrical energy from an ambient source, storing said electrical energy, and switching the storage device to provide electrical energy when required to a load such as a sensor. The example is provided of powering a sensor for monitoring tire pressure and transmitting that data.
Arms et al. in U.S. Pat. No. 7,696,621 (2010) and in a conference presentation, “Wireless Strain Sensing Networks,” 2nd European Workshop on Structural Health Monitoring, Munich, Germany, Jul. 7-9, 2004, describe a RFID tag packaging system for an electronic device located within a cavity in an adjacent flexible material. The dimensions of the flexible material are chosen so as to provide protection of the electronic device from loading applied to the device.
Bennett in U.S. Pat. No. 8,061,211 describes a seal with integrated sensor. This approach provides a seal member having both sealing and sensing functionality that is capable of sealing and determining if the seal is under proper compression or torque load. Moreover, the sealing material is preferably two concentric O-rings made of a dielectric material of low conductivity with electrically conducted or chemically reactive particulates within. Since liquid or gas seals are made of a variety of materials and have a multitude of design configurations that include, but are not limited to, (i) a circular conformable elastomer O-ring seated in a channel (gland) of a metallic or plastic fitting, (ii) circular washer made of soft conformable metallic or plastic material, (iii) flat gasket of various flat patterns made with conformable fibrous, cellulous, particulate, or polymeric material, (iv) circular compression fittings with offset tapered mating surfaces, (v) circular flared fittings with conformable flared tubings, and (vi) circular threaded pipe fittings with offset tapers, etc., an O-ring being only one of a multitude of design configurations, it is desirable to have a sensor configuration that is independent of the gasket configuration and material.
Another aspect of Bennett involves errors in the measurement of the compression or torque load that arise due to a non-uniform sealing material. A non-uniform material can arise due to non-uniform density of conductive particles within the seal material and due to a non-uniform thickness of the seal material. The magnitude of these errors is compounded and proportional to the area of the seal and so is of particular concern where the area of the seal is large as can be found in large diameter hydrocarbon transport pipelines that can be 12″, 18″, 24″, 30″, 36″, 48″ or larger in diameter.
U.S. Pat Application No. 2012/0043980 to Davis discloses a wear sensor comprises an electric circuit supported on a substrate. The circuit is electrically connected with a measuring device. As the sensor wears, the elements are sequentially decoupled from the circuit thereby changing the characteristic measured by the device. In another embodiment, as wear progresses, the conductors are progressively worn away thereby electrically decoupling the elements from the circuit although the elements themselves are never subjected to wear. Davis also discloses the communication lead could be connected to a wireless communication device.
European Pat No. EP0616144A1 to Klaus-Dieter et al. discloses a multi-stage wear sensor, in particular for brake pads.
U.S. Pat. No. 7,677,079 to Radziszewski et al. discloses a sensor for detecting erosion of a wear surface of a component, particularly a liner attached to the mill shell of a rotating grinding mill.
U.S. Pat. No. 7,270,890 to Sabol et al., discloses a system for monitoring the wear of a component. The component can include a base material which can be any of a number of materials including, for example, metals, ceramics, ceramic matrix composites, plastics, composites. The wear conductors may or may not be insulated from the surrounding environment. For instance, when the base material or the coating is an electrically insulating material and the wear conductors 20 are embedded therein.
A preferred approach to maintenance is “Condition-Based Maintenance” (“CBM”) or “Reliability Centered Maintenance” (“RCM”). Equipment downtime, both scheduled and unscheduled, is an important factor of production loss. In addition, according to a study by Optimal Maintenance Decisions Inc. (OMDEC), a leader in RCM management solutions, failures in the field are three times more costly to repair (considering overtime, rescue, and expedited shipping of parts) than scheduled (or preventive) maintenance operations.
Hence, CBM is replacing preventive maintenance in many industrial operations as a result of gains in productivity. CBM is a maintenance system prevalent in civil infrastructure, industrial mining and energy operations. CBM monitors industrial equipment, civil structures and their constituent components (collectively referred herein as “assets”) to establish an optimal maintenance cycle (based on the predictions of when a machine will fail using strain and vibration measurements, for example).
While preventive maintenance repairs machinery, civil structures and their constituent components every given time period, even if the asset is still operational, CBM can extend that time period. The optimal maintenance cycle determines the best time to shut down an asset for preventive repair. Finding the balance between repairing often and continuing to produce is often difficult.
As an example, strain and fatigue measurements reveal risks of yield failures and cracking, changes in material properties, and remaining equipment life, making them incredibly useful for CBM if monitored.
In the infrastructure, mining and energy industries, strain and vibration are not generally monitored by built-in systems, mainly due to the complexity of sensor installation and computational intensity of the data processing. CBM relies heavily on regular or continuous measurements of parameters that allow operators to determine when the asset will fail (i.e. strain and vibration).
Electronic sensors measure physical quantities (such as strain, temperature, acceleration, crack propagation, pressure, displacement, force, etc.) and convert them into signals read by an instrument (the reader varies depending on the type of sensor).
For example, strain gauges consist of a foil pattern (often in a tight zigzag) insulated in a flexible material and attached to an object under strain. As the object deforms, the resistance of the foil wires changes, allowing a Wheatstone bridge circuit (a measuring instrument used to measure an unknown electrical resistance) to record the variations.
In the energy, manufacturing and civil infrastructure industries flanges are commonly used to connect two separate components, such as spools of pipe, where a seal needs to be maintained between the components to contain a liquid or gas within the components. Such connections typically use a gasket that is compressed between the two flanges to provide a seal and prevent LOC. Thermal cycles, vibration, shock, fatigue, normal force and other mechanical influences cause the gaskets to loose their seal resulting in LOC.
It is known that sealing using conformable materials is achieved when such material is placed between relatively rigid mating surfaces and that sealing occurs when the material is put under pressure and displaces to conform to and fill the space between the mating surfaces.
It is also known that sealing of relatively rigid mating surfaces is achieved when such surfaces are in full or partial and often tight contact. Examples of such sealing are compression fittings and threaded pipe fittings that often have tapered mating surfaces that are offset to create tight contact during rotational tightening.
Unfortunately, existing CBM solutions have been historically inaccurate, are expensive or non-viable, and/or produce poor signal transmission and short battery life.
CBM's reliance on high data volume dictates a need to monitor continuously (or at least often) strain and loading. To understand fully an assets state requires monitoring of stress, accumulated stress, fatigue cycles, cracks and crack growth. However, monitoring the hundreds of assets used every day in a civil and industrial operations requires many sensors and many more wires, which are difficult and expensive to install and maintain. Moreover, the data requirements for continuous monitoring are large leading to large storage requirements and power consumption which negatively effects size and lifetime of the systems used to collect the data.
Many solutions have not reliably predicted when a machine or component will fail. This parameter is probably the most important when it comes to CBM, since CBM relies on accurate predictions of failure. The inability to predict correctly when an asset will fail can have grave consequences on unplanned downtime as well as operator safety.
Some solutions offer accurate predictions, but at high costs, whether in the stages of installation and setup, longevity and data collection, or analysis and data post-processing.
Yet other solutions offer poor signal transmission due to low range or lack of direct line of sight. Power supplies dictate operating conditions and longevity of the solution. Most solutions require too much power to operate for long periods of time, or are too delicate to operate in the harsh conditions of mining operations. Conditions can include extreme temperatures, constant vibration, and quick acceleration.
Accordingly, what is needed is a discrete sensor, separate from the seal or gasket, may be compatible with a multitude of seal configurations, may be constructed of different materials than those used to form the seal, and the performance of which is not affected by the size of the seal, that is capable of determining if the seal is under proper compression or torque load, and that is also capable of sensing contained fluid pressure and pressure variation indicating leakage across the sealing member. Further, what is needed is a sensor to detect when the compression of a gasket becomes compromised and a method to continuously monitor the integrity of the gasket and communicate this information so as to notify maintenance or other appropriate personnel to the condition of the seal. Moreover, a sensor that can provide an accurate indication of the gap between or displacement of a flange, provide for a gasket with its thickness minimally increased due to the sensor, provide an ability to route the sensor wiring about passages extending outside the flange, have separately replaceable components in service, and be provided in an economical fashion, both in manufacture and in use.
Moreover, it would be advantageous to be able to determine the pressure that the seal is under, and in particular, to determine any pressure variance around the course of the seal. This could be used to determine if the seal member is unseated, seated properly and evenly, and tightened under the appropriate compression or torque. In addition, it would be advantageous to be able to sense the contained fluid pressure being exerted onto the seal to ascertain if a leak path has been initiated there through.
Other seal sensors function by measuring pressure. Moreover, most pressure sensors, however, function by converting mechanical movement of a diaphragm to an electrical change in resistance or capacitance. This is achieved through the use of active materials like piezo film. However, such sensors are fairly costly, and in addition, it would be difficult to use such sensors to determine if a seal is under uniform pressure and seated properly.
Furthermore, other sensors function by measuring a relative difference in pressure between more than one sensor arranged circularly around the sealing surface and are not calibrated to measure the pressure or force accurately and do not measure displacement. Thus it would be difficult to use such sensors to quantitatively determine pressure or to measure the displacement between the sealing surfaces.
Other sensors are limited to a thickness that is the same as the sealing material. It would be difficult to use such sensors to align the sealing surfaces before assembly and compression or torque load due to there being compression on the seal during alignment procedures.
Accordingly, it would be advantageous to have a sensor that can measure the force and displacement at a location and is calibrated to provide a quantitative measurement of pressure, force or displacement or any combination thereof. Moreover, it would be advantageous to measure alignment of the sealing surfaces before the seal is compressed.
Loss of containment can also be the result of wear in the material providing the seal. Accordingly, it would be advantageous to have a sensor that can measure the wear of the material providing the containment.
According to an aspect, there is provided a discrete gasket sensor device, comprising a force sensor integrally formed within an elastic compressible material, the elastic compressible material translates displacement a first surface relative to a second surface into a force where the force sensor generates an electrical signal that is proportional to the displacement of the elastic compressible material. The sensor may be constructed of the same or similar material as the seal or gasket. Alternatively, the sensor may be constructed of a different material as the seal or gasket to alter or improve the sensitivity and other characteristics of the sensor. Preferably such sensor is separate and distinct from the seal or gasket and is compatible with a multitude of seal configurations and materials. Preferably, at least one or more of the sensors may be positioned along a circular path inside and parallel to the outer perimeter of the flange surface. Preferably, the performance of the sensor is not affected by the size of the seal or gasket and is capable of determining if the seal is under proper compression or torque load.
Another embodiment of the sensor involves sensing contained fluid pressure and pressure variation indicating leakage across the sealing member. Moreover, the sensor can provide an accurate indication of the gap or displacement between two opposing surfaces of a flange.
Preferably, the sensor is provided so that a seal or gasket thickness is not increased due to the size of the sensor. Alternatively, the seal or gasket is minimally increased due to the size of the sensor.
Preferably there is provided an ability to route the sensor wiring about passages extending outside the flange, have separately replaceable components in service, and be provided in an economical fashion, both in manufacture and in use.
There is provided a method to continuously monitor the integrity of the gasket involves measuring the signal from the sensor, calculating the compression or torque load or displacement and recording this data. The data may be communicated to another location in the immediate vicinity or to a remote location using wireless techniques described herein so as to notify maintenance or other appropriate personnel to the condition of the seal or gasket or the condition of the alignment of the flange before or during compression of the seal or gasket.
The sensor may include a force sensor and temperature sensor to provide temperature compensation to the force sensor. In another aspect, the sensor may include an integrated displacement sensor or an integrated displacement sensor and temperature sensor in combination, as well as any other suitable sensor desired for use in monitoring the movement of the faces of a flange or gasket. One or more sensors, of the same or different types, may be incorporated into each flange gap.
According to another aspect, the sensor may include a magnet to provide attachment of the sensor to the surface of the flange. Alternatively, the sensor may include an adhesive to provide attachment of the sensor to the surface. In yet another aspect, the sensor may include a threaded fastener to provide attachment of the sensor to the surface.
According to another aspect, there is provided a wireless gasket sensor device, comprising a processor connected to a wireless transmitter and at least one gasket sensor, and a power source connected to power the processor, the wireless transmitter and the gasket sensor. The processor has two or more states. There is at least one internal control element for sensing one or more predetermined conditions, the internal control element switching the processor between states based on the occurrence of at least one predetermined condition. A molded body encloses at least the processor, the wireless transmitter, and the internal control sensor such that the internal control sensor is physically isolated within the molded body.
According to another aspect, the molded body may also enclose at least one of the power source and one or more sensors connected to the processor.
According to another aspect, the processor may be connected wirelessly to a sensor that is external to the molded body or to an external sensor by conductors where a portion of the conductors is enclosed in the molded body, or both.
According to another aspect, at least one internal control element may be an accelerometer, and at least one predetermined condition may be the detection of one or more predetermined accelerations. At least one internal control element may be an RF transponder, and at least one predetermined condition may be the introduction or removal of an RF interrogator from its detection radius. At least one internal control element is a magnetic sensor, and at least one predetermined condition may be the introduction or removal of a magnetic element on an outer surface of the molded body. At least one internal control element may be a electromechanical switch, and at least one predetermined condition may be the actuation of the switch. At least one internal control element may be a temperature sensor or a non contact temperature sensor, and at least one predetermined condition may be a temperature cycle. At least one internal control element may be a gyro, and at least one predetermined condition may be the movement of the molded body.
According to another aspect, the molded body may enrobe at least the processor, the wireless transmitter, and the internal control sensor in a single piece construction.
According to another aspect, the at least one sensor may measure at least one of flange alignment, flange unloading, stud or bolt failure, gasket unloading, gasket creep, gasket disintegration and gasket failure.
According to another aspect, the at least one sensor may measure at least one of strain, cracks, crack propagation, motion, shock, acceleration, tilt, inclination, pressure, light, radiation, sound and chemical compounds.
According to another aspect, the processor may be programmed to process sensor data from the sensing element according to an algorithm and transmit the processed data by the wireless transmitter.
According to another aspect, the wireless transmitter may be a wireless transceiver.
According to another aspect, the gasket sensor device may comprise an attachment for attaching the gasket sensor to an object. The attachment may be at least one of a magnet, at least one welding flange, strapping, or an adhesive compound.
According to another aspect, the processor may be configured to operate as a node in a sensor network.
According to another aspect, there is provided a method of operating a wireless gasket sensor device, comprising the steps of: providing a wireless gasket sensor device as described above; configuring the internal control element to switch the processor between states upon the occurrence of at least one predetermined condition; and applying at least one predetermined condition to the internal control element.
According to another aspect there is provided a method to determine the pressure that the seal is under, and in particular, to determine any pressure variance around the course of the seal. This could be used to determine if the seal member is unseated, seated properly and evenly, and tightened under the appropriate compression or torque. In addition, it would be advantageous to be able to sense the contained fluid pressure being exerted onto the seal to ascertain if a leak path has been initiated there through.
According to another aspect, there is provided method to calibrate the sensor to provide a quantitative measure of the force, pressure or displacement, or any combination thereof, at the location of the sensor.
According to another aspect, there is provided a method to measure alignment of the sealing surfaces before the seal is compressed.
According to an aspect, there is provided a seal integrity sensor device, comprising a force sensor integrally formed within an elastic compressible material, the elastic compressible material having a first surface and a second surface opposite the first surface, the force sensor generating a signal in response to a compressive force applied to the first and second surfaces, the signal being indicative of the compressive force.
According to another aspect, the signal may be proportional to the displacement.
According to another aspect, the force sensor may measure at least one of flange alignment, flange unloading, stud or bolt failure, gasket unloading, gasket creep, gasket disintegration and gasket failure.
According to another aspect, the seal integrity sensor may further comprise a data collection device connected to receive data from the force sensor, the data collection device having a wireless communication module for communicating with a data network. The data collection device may comprises an attachment for attaching to an object.
According to another aspect, the force sensor may be sized to fit between flanges of a pipe connection.
According to an aspect, there is provided a wireless seal integrity sensor device, comprising a processor connected to a wireless transmitter; at least one seal integrity sensor connected to provide signals to the processor, each seal integrity sensor comprising a force sensor integrally formed within an elastic compressible material, the elastic compressible material having a first surface and a second surface opposite the first surface, the force sensor generating a signal in response to a compressive force applied to the first and second surfaces, the signal being indicative of the compressive force; a power source connected to power the processor and the wireless transmitter; and wherein the processor has two or more states and comprises at least one internal control element for sensing one or more predetermined conditions, the internal control element switching the processor between states based on the occurrence of at least one predetermined condition.
According to another aspect, the sensor device may further comprise a molded body that encloses at least the processor, the wireless transmitter, and the internal control sensor such that the internal control sensor is physically isolated within the molded body. The molded body may further enclose at least one of the power source and one or more sensors connected to the processor. At least one sensor may be external to the molded body and the processor is connected wirelessly to the at least one external sensor. At least one sensor may be external to the molded body and the processor is connected by a wired connection, where a portion of the wired connection is enclosed in the molded body. The molded body may enrobe at least the processor, the wireless transmitter, and the internal control sensor in a single piece construction.
According to another aspect, at least one internal control element may comprise one or more of: an accelerometer, and at least one predetermined condition comprises detecting one or more predetermined accelerations; an RF transponder, and at least one predetermined condition comprises introducing or removing an RF interrogator from its detection radius; a magnetic sensor, and at least one predetermined condition comprises the introduction or removal of a magnetic element on an outer surface of the molded body; a temperature sensor, and at least one predetermined condition comprises detecting a predetermined temperature; and a gyro, and at least one predetermined condition comprises detecting a predetermined movement.
According to another aspect, the at least one sensor may measure at least one of flange alignment, flange unloading, stud or bolt failure, gasket unloading, gasket creep, gasket disintegration and gasket failure.
According to another aspect, the processor may comprise instructions to process sensor data from the sensing element according to an algorithm and transmit the processed data by the wireless transmitter.
According to another aspect, the wireless transmitter may comprise a wireless transceiver.
According to another aspect, the processor may be configured to operate as a node in a sensor network.
According to an aspect, there is provided a method of operating a wireless seal integrity sensor device, the method comprising the steps of:
According to another aspect, the force sensor may be installed between pipes ends in a pipe connection.
According to an aspect, the force sensor may be installed by inserting the force sensor between two components in a connection.
These and other features will become more apparent from the following description in which reference is made to the appended drawings, the drawings are for the purpose of illustration only and are not intended to be in any way limiting, wherein:
There are many devices known to those skilled in the art for sensing various properties of matter, physical environment, and status of equipment. Typically, the data acquired by the sensor are stored and compared to predetermined values. In some cases, each reading is transmitted electronically to a central processor for evaluation. Alternatively, data may be transmitted electronically to a controller at intervals or when the data acquired fall outside predetermined limits.
Data may be transmitted using RF. In one example, this may be done as described by Powers et al. in U.S. Pat. No. 5,381,136.
Sensors may be isolated from harmful environments, such as corrosive atmospheres, or hazardous conditions, such as combustible gases, by containment of the sensor within a housing.
In other sensing devices, there are requirements including available power, reliability, and protection of and from the ambient environment that limit their applicability and which reduce their utility.
In particular, sensors attached to moving components of equipment, rotating components, components subject to wear may be themselves subjected to severe stresses, vibrations, or wear. It is desirable that sensors be small and have minimal mass to minimize imbalance that could lead to wear to failure. Additionally, components at interior points of equipment can have limited visibility or “line of sight” to the other sensors and data collection points and can be “blind”. It is desirable that sensors have the capability to operate independently of all other devices, and capability to transmit data wirelessly. Further, it is desirable that such systems be capable of operating in hazardous, harsh as well as laboratory or environmentally controlled environments.
The present discussion relates to wireless sensor devices, or sensors, that are intrinsically safe and easy to install by direct attachment to a component of equipment, and easy to use as it includes a sensor device and a wireless mote. Generally speaking, the sensor device provides readings to the wireless mote, and the wireless mote is used for control and communication. however, it will be understood from the discussion herein that these functions may be divided differently. For example, the sensor device may be formed within the wireless mote, or certain functions may be externalized from the wireless mote. Accordingly, the terms “mote” and “sensor” may be used interchangeably herein to refer to either the communication and control module, or the sensor device, or both the communication module and sensor device together. The communication module of the mote preferably contains within a protective body all components necessary for its intended purpose, such as additional components for sensing, communications, a tap sensitive user interface, a durable power source and ultra-low power operation. Advantages accrue from inclusion of a sensor interface and data acquisition components, memory, wireless transceiver, long life battery, a magnetic sensor, and capability for software over radio updates, data logging, and power management.
This device may be used to sense the status of a component of equipment, and may be designed to provide some or all of the following advantages:
The mote, or sensor, contains a source of power that may be batteries or, alternatively, a mote may be capable of being recharged so as to extend its operating life. Alternatively, the mote may scavenge or harvest power from its environment.
Further, to minimize power consumption, the mote may be capable of conserving power through power management functions such as operating one or more functions only when required and selectively controlling power to one or more components.
The position of a mote that is attached to moving equipment at any time can be determined using methods such as those described by El-Sheimy et al. in Report on Kinematic and Integrated Positioning Systems, FIX XXII International Congress, Washington, D.C., Apr. 19-26, 2002.
To these ends, a wireless mote 10 now will be described with reference to
Referring to
Referring to
Referring to
Sensor elements may be embedded within body 20, or, referring to
Referring to
Other power management options include harvesting energy from the environment, such as thermal energy, solar energy, kinetic energy, cathodic protection energy, or energy from radio waves.
Referring again to
Alternatively, referring to
Power management is implemented to reduce power consumption to improve lifetime of power source 208. Multiple level power saving techniques may be used by programming wireless mote 10 to perform one or more of the following means:
Referring to
A user normally would perceive that sleeping motes do not appear to exist because they are not in communication with other devices. However, user's computer can communicate with the database which has historical and forward projecting information. In this case, the user's view would merge the live mote data with the database data and show the real number of motes at any location. The database would also give information gathered during an earlier interaction to provide current status data, for example that a particular mote presently is “asleep” and that it will “wake up” at a particular time. In this manner, persistent forward and backward synthesis and correlation of the data will improve immensely a user's interaction with the wireless motes 10 when compared to prior art systems.
Additionally, magnetic sensor 212 can be activated remotely so as to “wake up” one or more specific wireless motes 10.
Referring to
Referring to
Internal Control Elements
Internal control elements are included in body 20 to allow a user to change the function of the embedded firmware between states. As body 20 is preferably a molded body solid with all the components embedded within the material, the one or more internal control elements will be physically isolated from an exterior surface of body 20. This allows internal control elements to change the state of the mote without compromising the inherently safe characteristics of body 20. Internal control elements may, for example, change the state to communicate in a different manner, or change between a wake/sleep state to help conserve power or otherwise. Referring to
In the case of an acceleration sensor, referring to
Referring to
What also is required is management of data received from a plurality of wireless motes 10, for which one option is illustrated in
Referring to
Referring to
Referring to
Applications
Gap Measurement—
Most pipelines experience strain, either tensile or compressive or sheer, on their critical parts such as flanges. Invariably, this leads to misalignment of the flanges, non uniform compression of the gasket, degradation of the gasket, fatigue of the gasket material, and eventual failure of the critical component. Typical methods to measure gasket integrity include visual inspection. The sensor describe herein may be used to measure the gap (or displacement) between opposing surfaces of a flange. Generally speaking, a gasket sensor is designed to elastically compress or otherwise deform when a compressive force is placed upon it. As it deforms its electrical conductivity changes. This, coupled with the geometry of the device, as well as the number of devices being read, will give the inspector a precise reading of the amount and direction of compressive force. Moreover, alignment of the opposing flange surface may be determined by comparing the relative compression of at least two gasket sensors placed along the perimeter of the flange surfaces within the gap between the flange surfaces and using geometry to calculate the relative position the opposing surfaces.
An experiment was set up to measure conductance as a function of the compression of the sensor. The sensor was positioned between two opposing surfaces of a flange. The distance between the two surfaces was measured and the corresponding conductance was recorded. The distance was adjusted and measured and the conductance value was recorded. This process was repeated until the distance was approximately 0.5 the starting distance. The results are illustrated in
Wear Measurement—
Referring to
Alternatively, inductive coupling may be used couple signals to the WSD circuit board 306 or to couple signals and power to the WSD circuit board 306.
The installation in a pipe will now be described, although it will be understood that the procedure may be generalized to other materials as well. Referring to
Referring to
In the example depicted in FIGS. 24 and 29-33, the WSD gauge circuit board 306 has two connection points 322 for connecting signal wires. There could be additional connection points for power wires or digital communication wires as well. A conductive trace 326 connects the attachment points 322 in
The circuit board 306 or other sensing means may be formed inside the shaft 302 of the WSD, or, referring to
Referring to
Referring to
Alternatively, a connector may be fixed to the top. Alternatively, a wire may extend from the top or side of the device.
A data collection and/or transmission device may be a Wireless Sensor Device as described in PCT patent publication no. WO2012/058770.
A pipeline integrity sensor was designed for monitoring the structural integrity of oil and slurry pipelines. In this example, the pipe wall thickness was monitored at critical locations. A Slurry Flow Loop (SFL) test facility was used for testing the pipeline integrity sensors.
Wear sensors were used for the pipe thickness measurement. The sensors were installed to critical locations on an 8″ diameter carbon steel test spool at the SFL. The data was collected using wireless sensing devices provided by Scanimetrics Inc. For assessment of the specific sensors results were compared using standard methods, such as ultrasonic thickness measurement and calipers to measure parameters for validation of the wireless sensor outputs.
An initial site survey was performed to verify cellular connectivity at the SFL. The installation of the pipeline integrity sensors included 6 wear sensors for the pipe thickness measurement, 8 stud tension sensors and 8 flange gap sensors for pipe flange integrity measurement. The wear sensors were installed with the NPT threaded outlets and proper sealing epoxy. Stud tension sensors were installed with proper torque wrench following standard tightening sequence up to the desired tension load, 120 ft lb. The pipe flange gap sensors were installed after the installation of the flanges with minimum initial stress in the sensors. The pipe flange sensors were attached t rength epoxy.
Below is the summary of installation of the pipeline integrity sensors:
Installed six wear sensors at the middle section of an A105 carbon steel test spool with 0.5″ wall thickness. Six sensors were installed at every 60 degrees of the pipe section, i.e. 0, 2, 4, 6, 8, 10 o'clock for pipeline thickness measurement at these locations as shown below.
Pipeline integrity sensors were designed for monitoring the structural integrity of oil and slurry pipelines. In this example the flange integrity was monitored at critical locations. A Pilot-Scale Slurry Flow Loop (SFL) facility was used for testing the pipeline integrity sensors.
Wear sensors were used for the pipe thickness measurement. The sensors were installed at critical locations on an 8″ diameter carbon steel test spool at the SFL facility. The data was collected using wireless sensing devices from Scanimetrics Inc. For assessment of the specific sensors, the results were compared using standard methods, such as digital torque gages and calipers, and ultrasonic tension measurement were used to manually measure parameters for validation of the wireless sensor outputs.
Pipeline integrity sensors were used for monitoring the structural integrity of oil and slurry pipelines. In this example, pipe wall thickness of a multi layer pipe was monitored, such as a Chromium Carbide Overlay pipe, Urethane Lined pipe, Rubber pipe and Rubber Lined pipe. In each case the sensor probe length was designed such that the distal end of the probe aligned with the wear surface at the time the sensor was installed.
Alternatively, the length of the probe could have been designed such that the distal end of the probe extended beyond the wear surface providing an way to calibrate the sensor for relative position due to insertion position errors, thread errors, etc. In another embodiment, the length of the probe could have been designed such that the distal end of the probe remained below the wear surface by 0.5 mm, 1.0 mm, 1.5 mm, 2.0 mm or more. Such a configuration would not actuate until the wear reached the distal end of the probe as described earlier.
The probe was designed to measure discrete wear steps of 0.25 mm, 0.5 mm, 0.75 mm, 1.0 mm, 1.5 mm, 2.0 mm. Other discrete wear steps could be used and they could be used in combination.
In this patent document, the word “comprising” is used in its non-limiting sense to mean that items following the word are included, but items not specifically mentioned are not excluded. A reference to an element by the indefinite article “a” does not exclude the possibility that more than one of the element is present, unless the context clearly requires that there be one and only one of the elements.
The following claims are to be understood to include what is specifically illustrated and described above, what is conceptually equivalent, and what can be obviously substituted. Those skilled in the art will appreciate that various adaptations and modifications of the described embodiments can be configured without departing from the scope of the claims. The illustrated embodiments have been set forth only as examples and should not be taken as limiting the invention. It is to be understood that, within the scope of the following claims, the invention may be practiced other than as specifically illustrated and described.
Number | Date | Country | |
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61992077 | May 2014 | US |