CN105181044A - Ultrasonic flowmeter - Google Patents

Abstract

The invention discloses an ultrasonic flowmeter, which belongs to the technical field of fluid flow measurement equipment. The flowmeter includes an outer casing, a meter head is arranged outside the outer casing, an inner casing is coaxially arranged inside the outer casing, and the outer casing and the outer casing are arranged coaxially. There is a circulation gap between the inner casings, and the two ends of the circulation gap are respectively provided with a first reflection sheet and a second reflection sheet, and the first reflection sheet and the second reflection sheet are provided with the same number of circulation channels extending in the axial direction. The flow channels on the opposite first reflection sheet and the flow passages on the second reflection sheet are all coaxially arranged, the end of the first reflection sheet is provided with a first reflective slope that is conically arranged, and the end of the second reflection sheet is provided with a cone. The second reflective slope is arranged in a shape, and the first probe and the second probe are arranged at intervals on the outer shell, and the first probe and the second probe are connected to the meter head. The flowmeter of the invention solves the technical problems of low measurement accuracy and wide measurement range of the transit-time ultrasonic flowmeter, and can be widely used in the measurement of fluid flow velocity.

Description

An ultrasonic flow meter

technical field

The invention relates to a flowmeter, more particularly to an ultrasonic flowmeter for a closed pipeline, which belongs to the technical field of fluid flow measurement equipment.

Background technique

Due to airtightness and opacity, the flow rate of the fluid in the closed pipeline cannot be known to the outside world. As the simplest measurement method, the flow rate of the fluid can usually be measured, and then the flow rate of the fluid can be calculated according to the diameter of the pipe. In this method, the common method is to use non-contact measurement, and the most common tool is ultrasonic flow meter.

The basic working principle of the ultrasonic flowmeter is as follows: when the ultrasonic wave propagates in the flowing fluid, it carries the information of the fluid flow velocity. Therefore, the flow velocity of the fluid can be detected by the received ultrasonic wave, and then converted into a flow rate. In this method, an ultrasonic pulse travels through the pipe from one sensor to the other. When the fluid is not flowing, the sound pulse propagates in both directions with the same speed (sonic speed, C), if the fluid in the pipe has a certain flow velocity V (the flow velocity is not equal to zero), the sound pulse along the flow direction will be transmitted faster, while the sound pulse against the flow direction will be transmitted slowly. In this way, the downstream travel time will be slightly shorter, while the upstream travel time will be slightly longer. Of course, the long or short mentioned here is compared with the transmission time when the fluid is not flowing.

According to different detection methods, ultrasonic flowmeters can be divided into different types of ultrasonic flowmeters such as propagation velocity difference method, Doppler method, beam shift method, noise method and correlation method. Among all these ultrasonic flowmeters, the principle and structure of the noise method are the simplest, easy to measure and carry, cheap but less accurate, especially suitable for use in occasions where the accuracy of flow measurement is not high.

In reality, the ultrasonic flowmeter based on the time difference principle is the most commonly used, which uses the relationship between the difference in propagation time and the measured flow velocity to obtain the flow velocity, and then obtain the flow rate. This type of flowmeter has many advantages, such as long life, low pressure loss, long-term stable operation, high reliability, etc., and it is because of these advantages that it has been widely used in urban water supply and drainage, petroleum, chemical, pharmaceutical, metallurgy and electric power In the field of liquid metering in other industries. However, this type of flowmeter also has certain defects, such as low measurement accuracy and low measurement range, which have always been technical problems that need to be solved at present.

Based on the above reasons, various ultrasonic flowmeters in the prior art still have some defects more or less, and there is also a demand for new ultrasonic flowmeters in practical applications. Therefore, for developing a new type of ultrasonic flowmeter, to change the traditional structure, not only has urgent research value, but also has good economic benefits and industrial application potential. lean on.

Contents of the invention

In order to overcome the defects of the existing ultrasonic flowmeters pointed out above, the present inventor has conducted in-depth research on this, and completed the present invention after paying a lot of creative work.

Specifically, the technical problem to be solved by the present invention is to provide an ultrasonic flowmeter to solve the technical problems of the time-of-flight ultrasonic flowmeter, such as low measurement accuracy and limited measurement range.

In order to solve the above-mentioned technical problems, the technical solution of the present invention is to provide an ultrasonic flowmeter, the ultrasonic flowmeter includes a cylindrical outer casing, the outer casing is provided with a meter head, and the inner casing of the outer casing An inner casing is arranged coaxially, a circulation gap is provided between the outer casing and the inner casing, and a first reflection sheet and a second reflection sheet are respectively provided at both ends of the flow gap, and the first reflection sheet and the second reflection sheet The second reflectors are cylindrical and fixed between the outer shell and the inner shell. The first reflector and the second reflector are provided with the same number of circulation channels extending axially. The circulation passages on the first reflection sheet and the circulation passages on the second reflection sheet are coaxially arranged, and the end of the first reflection sheet is provided with a conical first reflection slope, and the first reflection slope of the second reflection sheet The end is provided with a tapered second reflective slope, the first reflective slope is opposite to the second reflective slope, two measuring channels are arranged at intervals on the outer shell, and first a probe and a second probe, the first probe is close to the first reflection sheet and faces the first reflection slope, the second probe is close to the second reflection sheet and faces the second reflection slope, the Both the first probe and the second probe are connected to the meter head.

In the ultrasonic flowmeter of the present invention, as a preferred technical solution, the inner casing is provided with an axially extending adjustment passage, and a valve for adjusting the flow area of the adjustment passage is provided in the adjustment passage. The valve core is connected to the valve stem, and the valve stem passes through the inner shell and is rotatably mounted on the outer shell. moving mechanism.

In the ultrasonic flowmeter of the present invention, as a preferred technical solution, the stop mechanism includes a plurality of blind holes arranged in an annular array at the end of the valve stem, and the outer casing is provided with A mounting hole corresponding to the position of the blind hole. A steel ball matching the blind hole is provided in the mounting hole. The steel ball is connected to a compression spring. The compression spring is arranged in the mounting hole and leans against an adjustment The adjustment screw is threadedly connected to the outer casing.

In the ultrasonic flowmeter of the present invention, as a preferred technical solution, the end of the valve rod away from the blind hole is provided with a position sensor for recording the inclination position of the valve core, and the position sensor is connected to the statement header.

In the ultrasonic flowmeter of the present invention, as a preferred technical solution, a handle is provided on the end of the valve stem close to the blind hole, and the handle extends out of the outer shell, and A cover body is provided for covering the handle, the cover body is installed on the outer shell through fasteners, and a lead seal is provided between the cover body and the outer shell.

In the ultrasonic flowmeter of the present invention, as a preferred technical solution, the ends of the first probe and the second probe are respectively equipped with impurity removal devices for removing impurities attached to the probes.

In the ultrasonic flowmeter of the present invention, as a preferred technical solution, the impurity removal device includes a sleeve arranged in the flow gap, one end of the sleeve is open, and the other end is fixedly installed on the On the inner casing, the sleeve is slidably installed with a magnetic piston along the inside, and a number of through holes are provided on the end of the sleeve close to the inner casing; the valve core is provided with a permanent magnet.

In the ultrasonic flowmeter of the present invention, as a preferred technical solution, the permanent magnet is integrated with the valve core.

In the ultrasonic flowmeter of the present invention, as a preferred technical solution, a third probe and a fourth probe are installed at intervals on the outer casing, and the third probe and the fourth probe are arranged on the same busbar And the phase is staggered with the bus bar where the first probe is located, the third probe is close to the first reflective sheet and faces the first reflective slope, and the fourth probe is close to the second reflective sheet and faces the first Two reflective slopes, the third probe and the fourth probe are both connected to the meter head.

In the ultrasonic flowmeter of the present invention, as a preferred technical solution, the ends of the third probe and the fourth probe are respectively provided with the impurity removal device.

After adopting the above technical solution, the ultrasonic flowmeter of the present invention has achieved multiple beneficial effects, such as:

(1) Since the flow passages on the opposite first reflection sheet and the flow passages on the second reflection sheet are arranged coaxially, they have a good rectification effect, thereby improving the measurement accuracy of the ultrasonic flowmeter.

(2) Since the inner casing is provided with an axially extending adjustment channel, the adjustment channel is provided with a spool for adjusting the flow area of the adjustment channel. By changing the flow area of the fluid, the flow rate of the fluid can be changed, which also changes accordingly. The flow rate of the fluid flowing through the flow gap is changed, and the measurement range is changed accordingly.

(3) Since the stop mechanism adopts the compression spring and the adjustment screw connected by the steel ball, it plays an overload protection role for the ultrasonic flowmeter. When the pressure of the fluid in the pipeline is too high and the flow rate is high, the force of the compression spring is exceeded, and the steel ball will be When the compression spring is compressed, the valve core will lose its balance, which will drive the valve stem to rotate, increasing the flow area and reducing the flow rate.

(4) Since the magnetic piston is slid inside the sleeve and the valve core is provided with a permanent magnet, when the permanent magnet rotates with the valve core, a magnetic force can be applied to one end face of the magnetic piston, which can drive the magnetic piston to reciprocate Slide, spray the liquid in the sleeve, and spray it to the first probe or the second probe, so that the impurities attached to the first probe and the second probe can be removed, and this structure can clean the first probe and the second probe online , without stopping the machine or disassembling the ultrasonic flowmeter, it is simple and practical.

(5) Since the third probe and the fourth probe both connected to the meter head are also provided, a two-channel measurement mode is realized, the flow measurement error caused by the flow velocity disturbance is overcome, and the measurement accuracy is further improved.

As mentioned above, the present invention provides an ultrasonic flowmeter, which has achieved multiple excellent effects through the adoption of multiple unique technical features and structural design, and can solve the technical defects in the prior art, thus making it more popular in the industry It has good application potential and actual production prospect, as well as good market prospect.

Description of drawings

Fig. 1 is the structural representation of the ultrasonic flowmeter of the embodiment of the present invention;

Fig. 2 is a schematic top view of the ultrasonic flowmeter in Fig. 1;

Fig. 3 is a schematic structural view of A-A in the ultrasonic flowmeter of Fig. 1;

Fig. 4 is the structural representation of B-B in Fig. 3;

Fig. 5 is the enlarged schematic diagram of the structure of C in Fig. 3;

Fig. 6 is the enlarged schematic diagram of the structure of D in Fig. 3;

Fig. 7 is the enlarged schematic diagram of the section of E-E in Fig. 6;

Wherein, in FIG. 1 to FIG. 7 , each numeral signifies the following specific meanings, elements and/or components respectively.

In the figure: 1. Outer shell, 2. Meter head, 3. Inner shell, 4. Flow gap, 5. Second reflector, 6. Flow channel, 7. Valve core, 8. First probe, 9. Second Two probes, 10, third probe, 11, fourth probe, 12, position sensor, 13, valve stem, 14, first reflection sheet, 15, first reflection slope, 16, second reflection slope, 17, adjustment screw , 18, compression spring, 19, steel ball, 20, blind hole, 21, handle, 22, cover body, 23, lead seal, 24, sleeve, 25, magnetic piston.

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings and embodiments. However, the uses and purposes of these exemplary embodiments are only used to illustrate the present invention, and do not constitute any form of limitation to the actual protection scope of the present invention, nor limit the protection scope of the present invention thereto.

Example 1

As shown in Fig. 1 to Fig. 7 together, the present invention discloses an ultrasonic flowmeter, which includes a cylindrical outer shell 1, a meter 2 is arranged outside the outer shell 1, and a control and conversion meter is arranged inside the meter 2. Chips, these are consistent with the traditional principles, and will not be repeated here. The inner housing 3 is coaxially provided with the inner housing 3, and the inner housing 3 is also arranged as a linearly extending rotary structure. The outer housing 1 and the inner housing 3 is provided with a circulation gap 4, and the circulation gap 4 is equidistantly arranged, and the two ends of the circulation gap 4 are respectively provided with a first reflection sheet 14 and a second reflection sheet 5, and the first reflection sheet 14 and the second reflection sheet 5 are both Cylindrical structure and fixed between the outer shell 1 and the inner shell 3, the outer surfaces of the first reflective sheet 14 and the second reflective sheet 5 are fixed on the inner wall of the outer shell 1, the first reflective sheet 14 and the second reflective sheet The inner surfaces of the sheets 5 are all fixed on the outer wall of the inner casing 3, the first reflective sheet 14 and the second reflective sheet 5 are provided with the same number of circulation passages 6 extending axially, and the opposite first reflective sheet 14 The circulation channel 6 on the second reflection sheet 5 and the circulation channel 6 on the second reflection sheet 5 are all arranged coaxially, which has played a good rectification effect. The end of the sheet 5 is provided with a tapered second reflective slope 16, the first reflective slope 15 is opposite to the second reflective slope 16, and the outer casing 1 is provided with two measuring channels at intervals, and the measuring channels are respectively equipped with a second reflective slope 16. A probe 8 and a second probe 9, the first probe 8 is close to the first reflection sheet 14 and towards the first reflection slope 15, the second probe 9 is close to the second reflection sheet 5 and towards the second reflection slope 16, the first probe 8 and The second probes 9 are all connected to the meter head 2 . In order to prevent the liquid in the measuring channel from freezing at low temperature, when the first probe 8 and the second probe 9 are installed, the ends of the first probe 8 and the second probe 9 are at least flush with the inner wall of the outer shell 1, so that It is possible to make the first probe 8 and the second probe 9 flush with fluid all the time without freezing, or slightly protrude into the flow gap 4. Of course, the flushing effect is better, because once the If the distance is too large, eddy currents will be generated, which will affect the measurement results.

The inner casing 3 is provided with an axially extending adjustment channel, and the adjustment channel is provided with a spool 7 for adjusting the flow area of the adjustment channel. The spool 7 has a disc-shaped structure, and the swing of the spool 7 can change the flow area of the adjustment channel , the valve core 7 is connected to the valve stem 13, the valve stem 13 passes through the inner shell 3 and is rotatably mounted on the outer shell 1, a stop mechanism is provided between the valve stem 13 and the outer shell 1 to limit the rotation of the valve stem 13, through the stop The actuator can fix the valve stem 13 at a certain position, so that the flow area between the valve core 7 and the adjustment channel is constant, which changes the flow area of the fluid, thereby changing the flow rate of the fluid, increasing the flow area, and increasing the flow rate of the fluid. On the contrary, the flow area decreases and the flow velocity of the fluid increases, which correspondingly changes the flow rate of the fluid flowing through the flow gap 4, and the measurement range also changes accordingly.

The stop mechanism includes a number of blind holes 20 arranged in an annular array at the end of the valve stem 13. The outer casing 1 is provided with mounting holes corresponding to the positions of the blind holes 20, and steel balls matching the blind holes 20 are provided in the mounting holes. 19 , the steel ball 19 is connected with a compression spring 18 , the compression spring 18 is arranged in the installation hole and leans against an adjustment screw 17 , and the adjustment screw 17 is threadedly connected to the outer casing 1 .

The end of the valve stem 13 away from the blind hole 20 is provided with a position sensor 12 for recording the inclination position of the valve core 7. The position sensor 12 is connected to the meter head 2. When adjusting the position of the valve core 7, the flow area can be intuitively displayed through the position sensor 12. , easy to adjust.

The end of the stem 13 close to the blind hole 20 is provided with a handle 21, the handle 21 extends out of the outer shell 1, and the outer shell 1 is provided with a cover 22 for covering the handle 21, and the cover 22 is installed on the outer shell 1 through fasteners Above, a lead seal 23 is provided between the cover body 22 and the outer casing 1 . It is necessary to open the lead seal 23 to adjust the valve stem 13. The purpose of the lead seal 23 is to prevent the user from making random adjustments. The valve stem 13 is generally adjusted infrequently and only adjusted when the flow rate needs to be changed.

Example 2

As shown in Figures 1 to 7, the present invention discloses an ultrasonic flowmeter whose structure is basically the same as that of Embodiment 1, the difference being that the ends of the first probe 8 and the second probe 9 are equipped with corresponding The impurity removal device for removing the impurities attached to the probe, the impurity removal device includes a sleeve 24 arranged in the flow gap 4, the cross-sectional shape of the sleeve 24 is shuttle-shaped, and the sleeve 24 is in the fluid flow direction of the flow gap 4 The straight-line distance is greater than the straight-line distance in the flow gap 4 perpendicular to the flow direction, which avoids the impact of the fluid and affects the measurement effect. One end of the sleeve 24 is open, and the other end is fixedly installed on the inner shell 3. The sleeve 24 A magnetic piston 25 is slidably installed inside, and the end of the sleeve 24 near the inner casing 3 is provided with several through holes (not shown in the figure) to prevent back pressure from being generated when the magnetic piston 25 slides toward the inner casing 3, so that the magnetic The piston 25 can smoothly move to the inner casing 3; the valve core 7 is provided with a permanent magnet, and the permanent magnet and the valve core 7 are integrated, that is to say, the valve core 7 is made of a permanent magnet material. When the permanent magnet rotates with the spool 7, a magnetic force can be applied to one end face of the magnetic piston 25, which can drive the magnetic piston 25 to slide back and forth, eject the liquid in the sleeve 24, and spray it to the first probe 8 or The second probe 9, so that the impurities attached to the first probe 8 and the second probe 9 can be removed. This structure can clean the first probe 8 and the second probe 9 online without stopping the machine or disassembling the ultrasonic flowmeter, which is simple and convenient. And practical. After the cleaning is completed, the position of the spool 7 is adjusted, and the position of the permanent magnet is fixed. At this time, the magnetic piston 25 also finds a balance point, and the position is also fixed.

Example 3

As shown in Fig. 1 to Fig. 7 together, the present invention discloses an ultrasonic flowmeter, the structure of which is basically the same as that of Embodiment 2, the difference is that a third probe 10 and a fourth probe are installed at intervals on the outer shell 1 11. The third probe 10 and the fourth probe 11 are set on the same busbar and are out of phase with the busbar where the first probe 8 is located. As for the phase stagger angle, it is related to the diameter of the outer shell 1 and the measurement range. Those skilled in the art can use professional knowledge It is set that the third probe 10 is close to the first reflection sheet 14 and faces the first reflection slope 15, the fourth probe 11 is close to the second reflection sheet 5 and faces the second reflection slope 16, and the third probe 10 and the fourth probe 11 are connected Header 2. The ends of the third probe 10 and the fourth probe 11 are respectively equipped with impurity removal devices. The impurity removal devices have been introduced in detail in Embodiment 2 and will not be repeated here. This two-channel measurement method further improves the measurement accuracy.

Of course, based on the above idea, according to the change of the diameter of the outer casing 1, multi-channel four-channel or more channels can also be used to overcome the flow measurement error caused by the flow velocity disturbance. The installation method can refer to the above structure, here Do not give examples one by one.

The working principle of the present invention has not changed, it is the same as the traditional time-difference method ultrasonic flowmeter, but through the change of the technical scheme of the present invention, the measurement accuracy of the ultrasonic flowmeter is greatly improved, and the flow area of the adjustment channel can be changed to change Velocity and flow have expanded the measurement range of the ultrasonic flowmeter, making the ultrasonic flowmeter more widely used.

It should be understood that these examples are only used to illustrate the present invention and are not intended to limit the protection scope of the present invention. In addition, it should also be understood that after reading the technical content of the present invention, those skilled in the art can make various changes, modifications and/or variations to the present invention, and all these equivalent forms also fall within the appended claims of the present application. within the defined scope of protection.

Claims (10)

1. a ultrasonic flow meter, comprise the shell body that tubular is arranged, the outer setting of described shell body has gauge outfit, it is characterized in that: the inside of described shell body is coaxially arranged with inner housing, passage gaps is provided with between described shell body and inner housing, the two ends of described passage gaps are respectively equipped with the first reflector plate and the second reflector plate, described first reflector plate and the second reflector plate are tubular and are fixed between described shell body and inner housing, described first reflector plate and axially extended circulation passage identical with the second reflector plate being equipped with quantity, circulation passage on relative described first reflector plate and the circulation passage on described second reflector plate are all coaxially arranged, the end of described first reflector plate is provided with the first reflecting slant of taper setting, the end of described second reflector plate is provided with the second reflecting slant of taper setting, described first reflecting slant and the second reflecting slant are oppositely arranged, described shell body is interval with two Measurement channel, the first probe and the second probe is separately installed with in described Measurement channel, described first probe is near described first reflector plate and towards described first reflecting slant, described second probe is near described second reflector plate and towards described second reflecting slant, described first probe is all connected described gauge outfit with the second probe.

2. ultrasonic flow meter as claimed in claim 1, it is characterized in that: described inner housing is provided with axially extended adjustment passage, the spool adjusting described adjustment channel cross-sectional flow area is provided with in described adjustment passage, described spool connects valve rod, described valve rod passes described inner housing and rotates and is installed on described shell body, is provided with the stop mechanism limiting described valve rod and rotate between described valve rod and shell body.

3. ultrasonic flow meter as claimed in claim 1 or 2, it is characterized in that: described stop mechanism comprises some blind holes that annular array is arranged at described valve stem end, described shell body is provided with the mounting hole corresponding with described blind hole position, the steel ball suitable with described blind hole is provided with in described mounting hole, described steel ball connects a Compress Spring, described Compress Spring to be arranged in described mounting hole and to rely on an adjustment screw, and described adjustment screw thread is connected on described shell body.

4. as claimed in claim 2 or claim 3 ultrasonic flow meter, is characterized in that: described valve rod is provided with the position transducer for recording described spool incident angle away from one end of described blind hole, and described position transducer connects described gauge outfit.

5. the ultrasonic flow meter as described in any one of claim 2-4, it is characterized in that: the one end near described blind hole on described valve rod is provided with handle, described handle stretches out described shell body, described shell body is provided with the cover body for covering described handle, described cover body is installed on described shell body by securing member, is provided with lead sealing between described cover body and shell body.

6. the ultrasonic flow meter as described in any one of claim 2-5 as described in claim, is characterized in that: the equal correspondence in end of described first probe and the second probe is provided with the knot screen for removing the impurity be attached on probe.

7. ultrasonic flow meter as claimed in claim 6, it is characterized in that: described knot screen comprises the sleeve be arranged in described passage gaps, described sleeve open at one end, the other end is fixedly installed on described inner housing, be slidably fitted with magnetic piston in described sleeve edge, described sleeve is provided with some through holes near one end of described inner housing; Described spool is provided with permanent magnet.

8. ultrasonic flow meter as claimed in claim 7, is characterized in that: described permanent magnet and described spool are set to one.

9. the ultrasonic flow meter as described in any one of claim 1-8 as described in claim, it is characterized in that: on described shell body, also interval is provided with the 3rd probe and the 4th probe, described 3rd probe and the 4th is popped one's head in and to be arranged on same bus and to stagger phase place with the described first place bus of popping one's head in, described 3rd probe is near described first reflector plate and towards described first reflecting slant, described 4th probe is near described second reflector plate and towards described second reflecting slant, and described 3rd probe is all connected described gauge outfit with the 4th probe.

10. ultrasonic flow meter as claimed in claim 9, is characterized in that: the equal correspondence in end of described 3rd probe and the 4th probe is provided with described knot screen.