Instead, we bond a hard silicon rubber to the face of the transducer which acts as the ultrasound couplant. A mounting block secured by such a band may also be used, in which case the block may further include various screws for tightening down and aligning the transducer. Configure your matching product using our online configurator Configure It! The ultrasonic system of claim 1, wherein the transducer assembly couples a signal at a frequency between about 50 kHz and 1 MHz at a steep angle to skip in the conduit wall. We guarantee reliable operation up to our standard 4 meters cable length, even if a few users have experienced successful measurement with 20 meters extensions. By way of overview, the present invention addresses these limitations by arranging system components to provide counterpropagating signal paths across the gas of enhanced signal level and low noise by, on one hand providing a polarization- enhanced transmission signal launched so that a region of the wall acts as a coherent transmitter into the gas and, on the other hand, repolarizing the received signal to effectively discriminate against spurious received noise. We may use the information to improve our products and services. Composite transducers as described above were attached top a standard intervalometer. You acknowledge that such information and materials may contain inaccuracies or errors and we expressly exclude liability for any such inaccuracies or errors to the fullest extent permitted by law. CLAMP-ON ULTRASONIC FLOW METER FOR LOW DENSITY FLUIDS. With ultrasonic working transducer for measuring the flow rate of a fluid in a tube. While the block 55 is separated from the conduit by the damping layer 59, a window is provided in that layer through which the transducer assembly contacts the pipe wall directly. It would therefore be desirable to develop an external ultrasonic system for measuring the flow of low density liquids and fluids such as steam or gas in a conduit. The transmitter and receiver are preferably identical assemblies, and act, together with their mounting, as polarizers so that as transmitters they effectively enhance the signal of interest and, as receivers, reject other components of the pulse burst. This precisely orients the transducer and is shaped so the block thermally contacts the transducer assembly. The resulting ultrasonic wave is coupled into the test conduit (Figures 2A, 2B). As illustrated by the oblique mounting of the crystals, each transducer assembly may include includes a mounting block, wedge, guided wave buffer rod or similar arrangement for coupling energy between the crystal and the pipe, and configured to either carry a shear wave signal or produce such a signal by mode conversion and couple it to the wall at a defined angle. Additional layers or pads of damping material or fabric 59d may be provided, with further gel or grease 59c between successive layers to enhance transducer cooling on hot conduits, or reduce transducer cooling on cold or cryo conduits. attainable signal quality will be required before an effective external measurement system can be devised for these fluids, for flowing steam at low pressures, or for flare gas at atmospheric pressure. Neither we nor any third parties provide any warranty or guarantee as to the accuracy, timeliness, performance, completeness or suitability of the information and materials found or offered on this website for any particular purpose. Our Cypress Ultrasonic Flowmeter, designed for permanent, long term flow monitoring applications, always ships with a silicone grease. By way of example, in a steel pipe having a wall thickness of eight millimeters, a 500 kHz signal with a shear wavelength of six millimeters may be used, resulting in a skip length L. A suitable construction for a transducer for the practice of the present invention, includes a PZT crystal with both sides electroded by metal plating and mounted to a clamping wedge or mounting block to launch its signal s into or receive a signal from, the conduit. spaced small paths, possibly on small conduits, or using special measurement cells, or transducers extending into the free stream. Figures 3A and 3B show the received signal for transducers separations of three inches (Figure 3A) and six inches (Figure 3B) along the axis of the six-inch diameter pipe. The ultrasonic system of claim 1, wherein the conduit includes a carbon table spool piece and at least one of the transducer assemblies mounts on a carbon table. Further contributing to the difficulty of measurements, the gas or steam has a very low density and low sound speed so that very little signal can be coupled into and transmitted through it, or be detected above the level of background noise. As shown in those Figures, a six inch diameter pipe was cut through along a central axial plane, and the two hemicylindroid shells were reconnected using wooden strips which sealed the interior while blocking short circuit noise from passing between the two transducers. The transducers may be coupled to the conduit via a plastic wedge to launch a mode-converted shear wave signal into the wall as a skip or zigzag signal reflecting at a steep angle, or may couple via a stainless steel wedge of appropriate geometry to determine its launch angle into the conduit. This material includes, but is not limited to, the design, layout, look, appearance and graphics. The block 55 preferably has a surface 57, which is prefeably curved to a contour to match the conduit 2, and is mounted on the conduit over a layer of damping material 59 as described above. Today, we would like to talk briefly about coupling gels and why we use them at SoundWater. We provide high quality shielded RG316 coaxial cable extensions, with low line losses and a high resistance sheath.

It is also useful to apply damping material to the conduit along the length of conduit wall outside of the length on which the transducers reside, to reduce the amplitude of system noise entering the measurement segment. The present invention achieves one or more of the foregoing objects by providing first and second clamp-on ultrasonic signal transducers externally coupled or attached to a steam or gas conduit, and positioned to launch and receive contrapropagation signals along a path across the flowing fluid. We may change this policy from time to time by updating this page. if you have previously agreed to us using your personal information for direct marketing purposes, you may change your mind at any time by writing to or emailing us. We require this information to understand your needs and provide you with a better service, and in particular for the following reasons: We are committed to ensuring that your information is secure. 250ml - Supplied in a bottle with flip top for easy single use application. transducer with a disk-shaped emitter face that was actuated with substantially uniform power across its area by the multitude of individual cells 61. to ensure a solid transmission of the ultrasonic sound wave pulse and echo. Coupling gel is the goop/gel/grease that is added between the ultrasonic transducers on your flowmeter, and your pipe. The element 60 was fitted in a mounting to form a These links are provided for your convenience to provide further information. The transducers may couple to the conduit via a low sound speed mounting wedge, which is precisely aligned so that the vertically polarized shear wave component skips coherently, and the receiving transducer repolarizes the received signal, so that its coupling sensitivity to the fluid-borne signal effectively discriminates against crosstalk and noise going around the side of the conduit. We may use your personal information to send you promotional information about third parties which we think you may find interesting if you tell us that you wish this to happen. Pipes have a curved surface and bend away from the ultrasonic transducer creating a small gap. The transducer assembly may employ a damped crystal of dimensions effective to provide an output that converts to the desired waves in the pipe wall, i.e., to a vertically polarized shear wave signal, typically at a frequency between about 50 kHz and 1 MHz, depending on the acoustic properties of the fluid and the thickness of the pipe wall. Als je doorgaat met het gebruiken van deze site, gaan we er vanuit dat je ermee instemt. When thus accurately aligned along the axis, with this arrangement, the vertically polarized shear wave coupled into the pipe follows a skipping path as shown in Figure 1 which remains coherent for a distance of several skip lengths along the wall, energizing the wall to launch a narrow signal beam in a diametral plane across to the opposing transducer. Oscillator" IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency control. From time to time, this website may also include links to other websites. The lack of the lateral mode further prevented generation of unwanted crosstalk noise emanating from the transmitter.

This website contains material which is owned by or licensed to us. Unauthorised use of this website may give rise to a claim for damages and/or be a criminal offence. A cookie in no way gives us access to your computer or any information about you, other than the data you choose to share with us. The ultrasonic system of claim 1, wherein the first and second transducer assemblies repolarize signal energy received through the fluid and the conduit wall. The transducers employ a single mode crystal or preferably a high sensitivity broad single band transducer such as one formed as an array of cells constructed of a composite electroactive material, to produce, in the simplest case, a clean longitudinal pulse of relatively homogeneous power distribution across its face, and this is coupled by the wedge into an axially extending region of the conduit wall to launch the fluid-borne signal. For such situations the addition of solid acoustic reflectors is necessary. Advantageously, the mounting to thermally isolate a transducer holding block or plate adds further advantages for high temperature systems where noise has heretofor prevented effective clamp-on measurement. Your use of this website and any dispute arising out of such use of the website is subject to the laws of Australia.