CN208059950U - Orifice union, rectification and flow measurement device - Google Patents
Orifice union, rectification and flow measurement device Download PDFInfo
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- CN208059950U CN208059950U CN201820263765.8U CN201820263765U CN208059950U CN 208059950 U CN208059950 U CN 208059950U CN 201820263765 U CN201820263765 U CN 201820263765U CN 208059950 U CN208059950 U CN 208059950U
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Abstract
A kind of orifice union and the rectification including the orifice union and flow measurement device.Orifice union includes center throttling element and multiple peripheral throttling elements, multiple periphery throttling elements are sheathed on the outside of center throttling element successively, and it is coaxial with center throttling element, it is respectively formed annular fluid passage between center throttling element peripheral throttling element adjacent thereto, between adjacent peripheral throttling element, along the axial direction of center throttling element, annular fluid passage includes entrance contraction section, iso-cross-section section and export expansion section successively.The utility model generates sensitive clearly differential pressure signal while stabilization of fluidized, can improve the accuracy and reliability of flow measurement.
Description
Technical field
The utility model is related to field of flow measurement, and in particular to a kind of orifice union and the rectification including the orifice union
And flow measurement device.
Background technology
If being placed in the throttling element that a circulation area is less than conduit cross-sectional area in the pipeline full of fluid, in pipeline
Fluid beam just will produce local contraction or flow separation when by the throttling element, at contraction or separation, static pressure meeting
It reduces, therefore will produce certain pressure difference (also known as differential pressure) before and after throttling element.There are one between this pressure difference and flow
Fixed functional relation, therefore the forward and backward pressure difference measurements flow of the throttling element in measurement merging pipeline can be passed through.
In existing merging pipeline using between stagnation pressure and static pressure pressure difference realize flow measurement flow sensor with
Orifice plate (see Fig. 1), calibrating nozzle, Venturi tube, various even speed tubes are the most typical.Wherein, orifice plate, calibrating nozzle, Venturi tube
Difference is caused stress etc. being the contraction that occurs when flowing through measuring piece by fluid；Even speed tube by fluid mainly to flow through measuring piece
The separation of Shi Fasheng causes stress difference.In order to overcome the dresses such as the various pumps of upstream and downstream, valve, elbow, bypass in fluid transmission pipe
The influence of the unfavorable factors such as caused whirlpool, pulsation is set, these flow sensors are required for long in use
Front and back straight pipe, to ensure that the flowing when measuring flow in pipeline is fully developed standard pipe stream.Front and back straight pipe is wanted
Ask the application scenario for significantly limiting various flow sensors, thus engineers and technicians using various fairings come as early as possible
Ground makes the flow development in pipeline to standard state.
Existing fairing is usually made of the elongated channel of a branch of or several beams, if controlling the quantity in these channels, just
Flow constriction or separation can be caused before and after channel, so as to generate differential pressure for flow measurement；Reduce the density in channel simultaneously,
And these channels are set according to certain rule, advantageously reduce interacting between channel rear portion flow separation.It is based on
This thinking, engineers and technicians have developed tool as shown in Figure 2 a and 2 b based on the normal flows sensor such as orifice plate
There is the throttling set of porous channel, is used for rectification and flow measurement.
United States Patent (USP) US5341848, US5529093 all disclose it is a kind of it is with multiple circular channels, with certain thick
The plate fairing (i.e. multi-hole orifice) of degree.And according to certain rule to the size, quantity, present position of circular channel into
Row is appropriate to be arranged, to improve flow stability, flowing is made fully to develop as early as possible.
United States Patent (USP) US7051765 and Chinese patent CN200710162844.6 further disclose a kind of balance hole plate,
It is equally have multiple through-holes disposed according to certain rules, have certain thickness plate-like devices.On this balance hole plate
The size of through-hole, quantity, position are according to making the requirement that Reynolds number is equal in each through-hole be configured, to balance fluidised form, make stream
Dynamic fully development as early as possible, improves measuring accuracy.
Chinese patent CN201110344567.7, CN201120087553.7, CN201220273926.4 etc. are also announced
The multi-hole orifices of similar structures is used for flow measurement.Chinese patent CN201220323927.5 discloses a kind of Venturi type
Multi-hole orifice, each through-hole have the intermediate gradual thicker shape in thin both sides, i.e. Venturi type.When fluid flows through this orifice plate
When, since venturi shape is close to streamlined, reduce turbulent flow, to reduce front and back straight pipe requirement, also due to reducing
Turbulent flow, keeps pressure signal more stable, to improve measurement accuracy.Chinese patent CN201410241286.2 discloses one kind
Jet rose reaches same purpose using the calibrating nozzle of one or more groups of central symmetries distribution.
Although these prior arts promote the development of differential pressure type flow meter, but can not be in stabilization of fluidized
Sensitive clearly differential pressure signal is generated simultaneously, is still extremely improved space.
Utility model content
The purpose of this utility model is to propose a kind of orifice union and the rectification including the orifice union and flow measurement dress
It sets, to generate sensitive clearly differential pressure signal while stabilization of fluidized, improves the accuracy and reliability of flow measurement.
On the one hand the utility model provides a kind of orifice union, including center throttling element and multiple peripheral throttling elements, described
Multiple periphery throttling elements are sheathed on the outside of the center throttling element, and, the center coaxial with the center throttling element successively
It is respectively formed annular fluid passage between throttling element peripheral throttling element adjacent thereto, between adjacent peripheral throttling element, along institute
The axial direction of center throttling element is stated, the annular fluid passage includes that entrance contraction section, iso-cross-section section and outlet are expanded successively
Open section.
Preferably, the axial length of the center throttling element and the multiple peripheral throttling element is equal, and axial end face phase
Mutually alignment.
Preferably, the center throttling element is hourglass shape, and has isodiametric cylindrical central part, the periphery throttling element
For cylindrical shape, and mid diameter reduces to be formed in the middle part of isodiametric cylindrical shape, the cylindrical central part of the center throttling element and institute
The axial length stated in the middle part of the cylindrical shape of peripheral throttling element is equal.
Preferably, the center throttling element is spindle, and has isodiametric cylindrical central part, the periphery throttling element
Axial cross section for cylindrical shape, side wall is spindle, and the peripheral throttling element has in the middle part of isodiametric cylindrical shape, described
The cylindrical central part of center throttling element is equal with the axial length in the middle part of the cylindrical shape of the peripheral throttling element.
Preferably, it is equipped at least one through-hole in the middle part of the cylindrical shape of the peripheral throttling element.
Preferably, the area of the cross section of the annular fluid passage meets following formula (1), wherein the cross section is hung down
Directly in the axial direction of the center throttling element：
Wherein, i=1 ... N, N are the quantity of annular fluid passage；
SiFor the area of the cross section of the iso-cross-section section of i-th of annular fluid passage；
liFor the axial length of i-th of annular fluid passage；
viFor the flow velocity of the iso-cross-section section in i-th of annular fluid passage；
riFor the center radius of circle of the iso-cross-section section of i-th of annular fluid passage.
Preferably, the center throttling element is cylindricality, and the periphery throttling element is tubular, is throttled perpendicular to the center
On each axial section of part, the cross section of the center throttling element is rectangle, and the cross section of the periphery throttling element is
Rectangular-ambulatory-plane, along the axial direction of the center throttling element, the center throttling element includes first entrance contraction section, first etc. successively
Size section and first outlet expansion segment, the periphery throttling element include second entrance contraction section, the second equidimension section and the successively
Two export expansion sections.
Preferably, the area of the cross section of the annular fluid passage meets following formula (2), wherein the cross section is hung down
Directly in the axial direction of the center throttling element：
Wherein, i=1 ... N, N are the quantity of annular fluid passage；
SiFor the area of the cross section of the iso-cross-section section of i-th of annular fluid passage；
liFor the axial length of i-th of annular fluid passage；
viFor the flow velocity of the iso-cross-section section in i-th of annular fluid passage；
ziFor the half of the catercorner length of the central rectangular of the iso-cross-section section of i-th of annular fluid passage.
Preferably, the orifice union is for being set in pipe under test, and the pipe under test is cylindrical shape, and it is described in
Heart throttling element, the multiple peripheral throttling element and pipe under test coaxial arrangement, the inner wall of the pipe under test are equipped with ring
Shape protrusion, includes entrance contraction section, iso-cross-section to also be formed between the pipe under test peripheral throttling element adjacent thereto
The annular fluid passage of section and export expansion section, the arrival end close to the orifice union on the side wall of the pipe under test are set
There is high pressure pressure port, the iso-cross-section section close to the annular fluid passage is equipped with low pressure pressure port.
Preferably, the orifice union is for being set in pipe under test, and the pipe under test is cylindrical shape, and it is described in
Heart throttling element, the multiple peripheral throttling element and pipe under test coaxial arrangement, pipe under test periphery adjacent thereto
Between throttling element also formed include entrance contraction section, iso-cross-section section and export expansion section annular fluid passage, waited for described
On the side wall in test tube road close to the orifice union arrival end be equipped with high pressure pressure port, close to the annular fluid passage etc.
Cross-section segments are equipped with low pressure pressure port.
Preferably, the orifice union is for being set in pipe under test, and the pipe under test is square tube shape, and it is described in
Heart throttling element, the multiple peripheral throttling element and pipe under test coaxial arrangement, the inner wall of the pipe under test are equipped with ring
Shape protrusion, includes entrance contraction section, iso-cross-section to also be formed between the pipe under test peripheral throttling element adjacent thereto
The annular fluid passage of section and export expansion section, the arrival end close to the orifice union on the side wall of the pipe under test are set
There is high pressure pressure port, the iso-cross-section section close to the annular fluid passage is equipped with low pressure pressure port.
On the other hand the utility model provides a kind of rectification and flow measurement device, including：
Measurement pipe；
The orifice union, the orifice union are set in the measurement pipe；
Wherein, the center throttling element, the multiple peripheral throttling element and measurement pipe coaxial arrangement, the measurement pipe
Between peripheral throttling element adjacent thereto also formed include entrance contraction section, iso-cross-section section and export expansion section annular fluid
Channel is equipped with high pressure pressure port on the side wall of the measurement pipe close to the arrival end of the orifice union, close to the annular
The iso-cross-section section of fluid channel is equipped with low pressure pressure port.
Preferably, the inner wall of the measurement pipe is equipped with annular protrusion, to measurement pipe periphery section adjacent thereto
Stream part between also formed include entrance contraction section, iso-cross-section section and export expansion section annular fluid passage.
Preferably, the measurement pipe is cylindrical shape, and the area of the cross section of the annular fluid passage meets following formula
(1), wherein the cross section perpendicular to the measurement pipe axial direction：
Wherein, i=1 ... N, N are the quantity of annular fluid passage；
SiFor the area of the cross section of the iso-cross-section section of i-th of annular fluid passage；
liFor the axial length of i-th of annular fluid passage；
viFor the flow velocity of the iso-cross-section section in i-th of annular fluid passage；
riFor the center radius of circle of the iso-cross-section section of i-th of annular fluid passage.
Preferably, the measurement pipe is square tube shape, and the area of the cross section of the annular fluid passage meets following formula
(2), wherein the cross section perpendicular to the measurement pipe axial direction：
Wherein, i=1 ... N, N are the quantity of annular fluid passage；
SiFor the area of the cross section of the iso-cross-section section of i-th of annular fluid passage；
liFor the axial length of i-th of annular fluid passage；
viFor the flow velocity of the iso-cross-section section in i-th of annular fluid passage；
ziFor the half of the catercorner length of the central rectangular of the iso-cross-section section of i-th of annular fluid passage.
Preferably, the rectification and flow measurement device further include high pressure pressure guiding pipe, low pressure pressure guiding pipe and differential pressure transmitter,
One end of the high pressure pressure guiding pipe is connected to the high pressure pressure port, and the other end is connected to the high-pressure side of the differential pressure transmitter
Mouthful, one end of the low pressure pressure guiding pipe is connected to the low pressure pressure port, and the other end is connected to the low pressure of the differential pressure transmitter
Port.
The beneficial effects of the utility model are：Due to the squeezing action of annular fluid passage, fluid enters annular fluid
Flow velocity quickening, pressure reduction, velocity flow profile are easy to be organized into the form for standard of comparison behind channel.The VELOCITY DISTRIBUTION of pipe stream
Pipe stream is further adjusted, just by the state being originally layered using coaxial annular fluid passage by different levels
(i.e. shorter distance ground) flow regime can quickly be standardized.
Since orifice union can make the fluid in pipe under test flow fast and stable, regular velocity flow profile is formed,
From without installing required front and back straight pipe when existing flow measurement device measures, the requirement to field condition is reduced.
Annular fluid passage can form pressure drop and can be used for flow measurement to generate while carrying out rectification to tube fluid state
Stabilization, high s/n ratio differential pressure signal, to improve the precision and reliability of flow measurement.
Annular fluid conduit successively include entrance contraction section, iso-cross-section section and export expansion section annular fluid passage,
When fluid stream is through orifice union, pressure reaches maximum in front of entrance contraction section, near minimum in iso-cross-section section pressure,
Export expansion section pressure is restored, and can form pressure drop to generate the differential pressure signal that can be used for flow measurement.
Description of the drawings
The utility model exemplary embodiment is described in more detail in conjunction with the accompanying drawings, the utility model it is above-mentioned
And other purposes, feature and advantage will be apparent, wherein identical in the utility model exemplary embodiment
Reference numeral typically represents same parts.
Fig. 1 shows the scheme of installation of existing orifice flowmeter；
Fig. 2 a and Fig. 2 b show the schematic diagram of the existing throttling set with porous channel respectively；
Fig. 3 shows the rectification of first embodiment according to the present utility model and the sectional view of flow measurement device；
Fig. 4 shows the rectification of first embodiment according to the present utility model and the side view of flow measurement device；
Fig. 5 shows the stereogram of the orifice union of first embodiment according to the present utility model；
Fig. 6 shows the sectional view of the orifice union of first embodiment according to the present utility model；
Fig. 7 shows the rectification of first embodiment according to the present utility model and the annular fluid passage of flow measurement device
The sectional view of iso-cross-section section；
Fig. 8 shows the stereogram of the orifice union of second embodiment according to the present utility model；
Fig. 9 shows the sectional view of the orifice union of second embodiment according to the present utility model；
Figure 10 shows the rectification of 3rd embodiment according to the present utility model and the sectional view of flow measurement device；
Figure 11 shows the stereogram of the orifice union of 3rd embodiment according to the present utility model；
Figure 12 shows the sectional view of the orifice union of 3rd embodiment according to the present utility model；
Figure 13 shows the stereogram of the orifice union of fourth embodiment according to the present utility model；
Figure 14 shows the sectional view of the orifice union of fourth embodiment according to the present utility model；
Figure 15 shows the stereogram of the orifice union of the 5th embodiment according to the present utility model；
Figure 16 shows the sectional view of the orifice union of the 5th embodiment according to the present utility model；
Figure 17 shows the rectification of the 5th embodiment according to the present utility model and the annular fluid passage of flow measurement device
Iso-cross-section section sectional view.
Reference sign：
101- orifice plates, 102- measure mouth, 103- steel pipes；
1- annular fluid passages, 1a- annular fluid passages, 1b- annular fluid passages, the centers 2- throttling element, the peripheries 3- section
Flow part, 4- high pressure pressure ports, 5- low pressure pressure ports, 6- differential pressure transmitters, 7- computers, 8- measurement pipes, 9- support elements, 10- rings
Shape protrusion, 11- through-holes.
Specific implementation mode
The utility model is more fully described below with reference to accompanying drawings.Although showing the preferred of the utility model in attached drawing
Embodiment, however, it is to be appreciated that may be realized in various forms the utility model without should be limited by embodiments set forth here
System.On the contrary, these embodiments are provided so that the utility model is more thorough and complete, and can be by the utility model
Range is completely communicated to those skilled in the art.
Orifice union according to the utility model embodiment includes center throttling element and multiple peripheral throttling elements, multiple peripheries
Throttling element is sheathed on the outside of center throttling element successively, and coaxial with center throttling element, center throttling element periphery adjacent thereto
It is respectively formed annular fluid passage between peripheral throttling element between throttling element, adjacent, along the axial direction of center throttling element, ring
Shape fluid channel includes entrance contraction section, iso-cross-section section and export expansion section successively.
In use, orifice union may be disposed in pipe under test, according to the shape of orifice union, pipe under test can be circle
Tubular or square tube shape, and center throttling element, multiple peripheral throttling elements and pipe under test coaxial arrangement, pipe under test are adjacent thereto
Between peripheral throttling element also formed include entrance contraction section, iso-cross-section section and export expansion section annular fluid passage, waiting for
It is equipped with high pressure pressure port close to the arrival end of orifice union on the side wall in test tube road, close to the iso-cross-section section of annular fluid passage
Equipped with low pressure pressure port.
When carrying out flow measurement to pipe under test, perfect condition is that the flow regime in pipeline is fully developed pipe stream.
Thus in actual industrial process control or trade settlement, there is strictly the front and back straight pipe that should be arranged when being installed to various flowmeters
It is required that ensure that pipe stream fully develops the accuracy for ensureing to measure and reliability.However in practice, by field condition
Limitation, can not usually ensure the setting of straight pipe, so various fairings come into being.In addition, in design discharge timing,
It is also contemplated that it has preferable detectability, to improve flow measurement accuracy and reliability.
When being installed in pipe under test according to the orifice union of the utility model embodiment, the pipe under test of coaxial arrangement,
Center throttling element and peripheral throttling element form multiple coaxial annular fluid passages.Due to the squeezing action of annular fluid passage,
Fluid enters flow velocity quickening, pressure reduction after annular fluid passage, and velocity flow profile is easy to be organized into the shape for standard of comparison
State.Pipe stream is further pressed difference by the state that the VELOCITY DISTRIBUTION of pipe stream is originally layered using coaxial annular fluid passage
Level be adjusted, can quickly (i.e. shorter distance ground) flow regime be standardized.Since orifice union can make to wait for
Fluid in test tube road flows fast and stable, forms regular velocity flow profile, from without installing existing flow measurement device
Required front and back straight pipe, reduces the requirement to field condition when measurement.
In addition, annular fluid passage includes entrance contraction section, iso-cross-section section and export expansion section successively, shunk in entrance
Section, (i.e. orifice union is installed in pipe under test along the axial direction of center throttling element for the cross-sectional area of annular fluid passage
Fluid flow direction later) be gradually reduced, in iso-cross-section section, the cross-sectional area of annular fluid passage keep constant it is constant,
Gradually increase along the axial direction of center throttling element in the cross-sectional area of export expansion section, annular fluid passage.Work as fluid stream
When through orifice union, pressure reaches maximum in front of entrance contraction section, is minimized in iso-cross-section section pressure, in export expansion
Section pressure is restored, and can form pressure drop to generate the differential pressure signal that can be used for flow measurement.When measurement, in pipe under test
Side wall on close to orifice union arrival end be arranged high pressure pressure port, on side wall close to annular fluid passage iso-cross-section
Section setting low pressure pressure port (low pressure pressure port is preferably provided at the axial centre face of iso-cross-section section), passes through high pressure pressure
Hole and low pressure pressure port carry out pressure, and utilize pressure sensor or differential pressure pick-up measure differences in pressure, and then can calculate logical
Cross the flow of pipe under test.Since the rectification effect of this orifice union is good, can be stablized, the differential pressure of high s/n ratio
Signal, to improve the precision and reliability of flow measurement.
In one example, the axial length of center throttling element and multiple peripheral throttling elements is equal, and axial end face is mutual
Alignment, in favor of formed include entrance contraction section, iso-cross-section section and export expansion section annular fluid passage.
In one example, center throttling element is hourglass shape, and has isodiametric cylindrical central part, and peripheral throttling element is
Cylindrical shape, and mid diameter reduces to be formed in the middle part of isodiametric cylindrical shape, cylindrical central part and the periphery of center throttling element throttle
Axial length in the middle part of the cylindrical shape of part is equal.It, being capable of shape by center throttling element and periphery throttling element with above-mentioned shape
At the annular fluid passage including entrance contraction section, iso-cross-section section and export expansion section.In this case, work as orifice union
When being set in pipe under test, annular protrusion is set on the inner wall of pipe under test in advance, to which pipe under test is adjacent thereto
Between peripheral throttling element also formed include entrance contraction section, iso-cross-section section and export expansion section annular fluid passage.The ring
The axial cross section of shape protrusion can be trapezoidal.
In one example, center throttling element is spindle, and has isodiametric cylindrical central part, and peripheral throttling element is
The axial cross section of cylindrical shape, side wall is spindle, and peripheral throttling element has in the middle part of isodiametric cylindrical shape, center throttling element
Cylindrical central part it is equal with the axial length in the middle part of the cylindrical shape of peripheral throttling element.It is throttled by the center with above-mentioned shape
Part and peripheral throttling element, can form the annular fluid passage including entrance contraction section, iso-cross-section section and export expansion section.
In one example, at least one through-hole is equipped in the middle part of the cylindrical shape of peripheral throttling element.Preferably, through-hole is more
It is a, and peripherally the circumferential direction of throttling element is uniformly arranged.Through-hole can be connected to adjacent annular fluid passage, keep each annular fluid logical
Pressure in road is of substantially equal.In this case, the iso-cross-section section by being set on side wall close to annular fluid passage
Low pressure pressure port can obtain the average pressure in each annular fluid passage, be conducive to obtain stable pressure signal.Through-hole
It can be round or oval, be preferably disposed on the axial centre face in the middle part of the cylindrical shape of peripheral throttling element.
In one example, the area of the cross section of annular fluid passage meets following formula (1), and wherein cross section is vertical
In the axial direction of center throttling element：
Wherein, i=1 ... N, N are the quantity of annular fluid passage；
SiFor the area of the cross section of the iso-cross-section section of i-th of annular fluid passage；
liFor the axial length of i-th of annular fluid passage；
viFor the flow velocity of the iso-cross-section section in i-th of annular fluid passage；
riFor the center radius of circle of the iso-cross-section section of i-th of annular fluid passage.
By the measuring of the numerical simulation and experimental fluid mechanics (EFD) of Fluid Mechanics Computation (CFD), work as annular flow
When the area of the cross section in body channel meets above-mentioned formula (1), orifice union has best rectification effect, corresponding flow measurement
Precision highest.
In one example, all annular fluid passages are (including between center throttling element peripheral throttling element adjacent thereto
Annular fluid passage, the annular fluid passage between adjacent peripheral throttling element and pipe under test periphery section adjacent thereto
Annular fluid passage between stream part) the area of cross section be satisfied by following formula (1), wherein cross section is perpendicular to waiting for test tube
The axial direction in road：
Wherein, i=1 ... N, N are the quantity of annular fluid passage；
SiFor the area of the cross section of the iso-cross-section section of i-th of annular fluid passage；
liFor the axial length of i-th of annular fluid passage；
viFor the flow velocity of the iso-cross-section section in i-th of annular fluid passage；
riFor the center radius of circle of the iso-cross-section section of i-th of annular fluid passage.
In actual use, the flow velocity in each annular fluid passage can be determined according to actual condition, for example, when being applied to
When long straight pipeline and relatively smooth inner wall of the pipe, the flow velocity in each annular fluid passage is of substantially equal；When applied to long straight tube
When road but larger inner wall of the pipe roughness, the flow velocity in the annular fluid passage for measuring tube hub is larger.
In one example, center throttling element is cylindricality, and peripheral throttling element is tubular, in the axis perpendicular to center throttling element
To each section on, the cross section of center throttling element is rectangle, and the cross section of peripheral throttling element is rectangular-ambulatory-plane, along centromere
Flow part axial direction, center throttling element successively include first entrance contraction section, the first equidimension section and first outlet expansion segment,
Peripheral throttling element includes second entrance contraction section, the second equidimension section and second outlet expansion segment successively.
Wherein, along the axial direction of center throttling element, (fluid after i.e. orifice union is installed in pipe under test flows
Direction), the size (long and wide) of the rectangular cross section of the first entrance contraction section of center throttling element is gradually reduced, the first equidimension
The size of the rectangular cross section of section keeps constant constant, and the size of the rectangular cross section of first outlet expansion segment gradually increases.It is excellent
Selection of land, the length of rectangular cross section and the wide equal proportion variation centered on the axis of center throttling element respectively.Similar, along centromere
Flow the axial direction of part, the size of the rectangular-ambulatory-plane cross section of the second entrance contraction section of peripheral throttling element (length of periphery and it is wide with
And the length and width of inner circumferential) be gradually reduced, the size of the rectangular-ambulatory-plane cross section of the second equidimension section keeps constant constant, second outlet
The size of the rectangular-ambulatory-plane cross section of expansion segment gradually increases.
Similar, the area of the cross section of annular fluid passage meets following formula (2), wherein the cross section perpendicular to
The axial direction of the center throttling element：
Wherein, i=1 ... N, N are the quantity of annular fluid passage；
SiFor the area of the cross section of the iso-cross-section section of i-th of annular fluid passage；
liFor the axial length of i-th of annular fluid passage；
viFor the flow velocity of the iso-cross-section section in i-th of annular fluid passage；
ziFor the half of the catercorner length of the central rectangular of the iso-cross-section section of i-th of annular fluid passage.
Central rectangular is the rectangle positioned at the centre position of annular fluid passage periphery and inner circumferential, the side of central rectangular with it is outer
Week is equal with the distance of inner circumferential.
In one example, support connector is equipped in annular fluid passage, support connector can be supporting rod or branch
Blade.Support peripheral throttling element that connector can be adjacent thereto to center throttling element, between adjacent peripheral throttling element and
Pipe under test peripheral throttling element adjacent thereto is supported and connects, and the relative position between these components is kept to fix.It is excellent
Selection of land, support connector are uniformly distributed in relative to the axis of pipe under test in annular fluid passage.
The utility model embodiment also provides a kind of rectification and flow measurement device, including：
Measurement pipe；
The orifice union, orifice union are set in measurement pipe；
Wherein, center throttling element, multiple peripheral throttling elements and measurement pipe coaxial arrangement, measurement pipe periphery section adjacent thereto
Stream part between also formed include entrance contraction section, iso-cross-section section and export expansion section annular fluid passage, in measurement pipe
It is equipped with high pressure pressure port close to the arrival end of orifice union on side wall, the iso-cross-section section close to annular fluid passage is equipped with low pressure
Pressure port.
The rectification and flow measurement device can be more convenient, accurately carry out rectification and flow measurement.In use, by rectification
And flow measurement device is concatenated with pipe under test, without carrying out installation of the orifice union in pipe under test, and is conducive to
The alignment for ensureing each annular fluid passage, to improve measurement accuracy.
It the measurement process and principle of the rectification and flow measurement device and was measured above with reference to described in orifice union
Journey and principle are identical, and details are not described herein.
In one example, the inner wall of measurement pipe is equipped with annular protrusion, to measurement pipe periphery throttling adjacent thereto
Between part also formed include entrance contraction section, iso-cross-section section and export expansion section annular fluid passage.
In one example, measurement pipe is cylindrical shape, and the area of the cross section of annular fluid passage meets following formula
(1), wherein axial direction of the cross section perpendicular to measurement pipe：
Wherein, i=1 ... N, N are the quantity of annular fluid passage；
SiFor the area of the cross section of the iso-cross-section section of i-th of annular fluid passage；
liFor the axial length of i-th of annular fluid passage；
viFor the flow velocity of the iso-cross-section section in i-th of annular fluid passage；
riFor the center radius of circle of the iso-cross-section section of i-th of annular fluid passage.
In one example, measurement pipe is square tube shape, and the area of the cross section of annular fluid passage meets following formula
(2), wherein axial direction of the cross section perpendicular to measurement pipe：
Wherein, i=1 ... N, N are the quantity of annular fluid passage；
SiFor the area of the cross section of the iso-cross-section section of i-th of annular fluid passage；
liFor the axial length of i-th of annular fluid passage；
viFor the flow velocity of the iso-cross-section section in i-th of annular fluid passage；
ziFor the half of the catercorner length of the central rectangular of the iso-cross-section section of i-th of annular fluid passage.
In one example, rectification and flow measurement device further include high pressure pressure guiding pipe, low pressure pressure guiding pipe and differential pressure transporting
One end of device, high pressure pressure guiding pipe is connected to high pressure pressure port, and the other end is connected to the high pressure port of differential pressure transmitter, low pressure impulse
One end of pipe is connected to low pressure pressure port, and the other end is connected to the low-pressure port of differential pressure transmitter.
According to the differential pressure between high pressure port and low-pressure port, the flow by measurement pipe, such as following formula can be calculated
(3) and shown in (4)：
Wherein：
qvFor volume flow；
qmFor mass flow；
α is discharge coefficient, is calibrated and is determined by experimental data；
ε is com-pressible factor, and when fluid is incompressible state, ε=1 passes through school when fluid is compressed state
Quasi-experiment data obtain the value of ε；
D is the equivalent diameter of standard toroidal fluid channel,
ρ is measured medium density；
Δ P is differential pressure.
In one example, the both ends of measurement pipe are respectively equipped with connecting flange, can pass through connecting flange and pipe under test
It is attached.
Embodiment 1
Fig. 3 and 4 shows the rectification of first embodiment according to the present utility model and the sectional view of flow measurement device respectively
And side view, Figures 5 and 6 show the stereogram and sectional view of the orifice union of first embodiment according to the present utility model respectively,
Fig. 7 shows the sectional view of the rectification of first embodiment according to the present utility model and the annular fluid passage of flow measurement device.
Include measurement pipe according to the rectification of the utility model first embodiment and flow measurement device as shown in the figures above
8 and the orifice union in measurement pipe 8.Wherein, orifice union includes center throttling element 2 and multiple peripheral throttling elements 3.Center
Throttling element 2 is hourglass shape, and has isodiametric cylindrical central part.Peripheral throttling element 3 is cylindrical shape, and mid diameter reduces shape
At in the middle part of isodiametric cylindrical shape, the side wall of peripheral throttling element 3 has certain thickness.Measurement pipe 8 is cylindrical shape, and inner wall is equipped with
The axial cross section of annular protrusion 10, annular protrusion is trapezoidal.Multiple periphery throttling elements 3 are sheathed on the outer of center throttling element 2 successively
Portion, center throttling element 2, multiple peripheral throttling elements 3 and measurement pipe 8 are coaxially disposed, the periphery throttling adjacent thereto of center throttling element
It is respectively formed annular flow between peripheral throttling element between part, adjacent and between peripheral throttling element that measurement pipe is adjacent thereto
Body channel 1, wherein annular fluid passage 1a are near the side wall of measurement pipe 8, axis of the annular fluid passage 1b near measurement pipe 8
Line.Along the axial direction of center throttling element 2, annular fluid passage 1 includes that entrance contraction section, iso-cross-section section and outlet are expanded successively
Open section.Support connector 9 is equipped in each annular fluid passage 1, support connector 9 is to center throttling element 2 and peripheral support
Part 3 plays fixed supporting role.
Multiple circular through-holes 11 (see Fig. 6) are equipped in the middle part of the cylindrical shape of each peripheral throttling element 3, these are circular logical
Hole 11 is uniformly distributed along the circumferential direction of peripheral throttling element 3.
It is equipped with high pressure pressure port 4 close to the arrival end of orifice union on the side wall of measurement pipe 8, in the side wall of measurement pipe 8
The centre position of the iso-cross-section section of upper annular fluid passage is equipped with low pressure pressure port 5.One end connection of high pressure pressure guiding pipe is supreme
Pressure port 4, the other end is pressed to be connected to the high pressure port of differential pressure transmitter 6, one end of low pressure pressure guiding pipe is connected to low pressure pressure port
5, the other end is connected to the low-pressure port of differential pressure transmitter 6.Difference transmitter 6 is connect with computer 7.
In the present embodiment, center throttling element 2 is equal with the axial length of multiple peripheral throttling elements 3, and center throttling element 2
It is mutually aligned with the axial end face of multiple peripheral throttling elements 3.The area of the cross section of annular fluid passage meets formula (1), public
S in formula (1)iAnd ri(i=1,2,3) mark is in Fig. 7.
In use, rectification and flow measurement device are concatenated with pipe under test, when fluid flow to the device from pipe under test, by
In the barrier effect of orifice union, higher pressure is generated in the arrival end of orifice union, by measurement pipe side wall
High pressure is transferred to the high pressure port of differential pressure transmitter by high pressure pressure port and pressure guiding pipe；Due to the barrier effect of throttling element, fluid
It can only pass through from annular fluid passage, be minimized in iso-cross-section section pressure, pass through the low pressure on measurement pipe side wall
Low pressure is transferred to the low-pressure port of differential pressure transmitter by pressure port and pressure guiding pipe；Differential pressure transmitter is by high-voltage signal and low-voltage signal
Computer is passed to, corresponding flow is calculated according to formula (3) or (4) by computer.
Embodiment 2
Fig. 8 and 9 shows the stereogram and sectional view of the orifice union of second embodiment according to the present utility model respectively.The
Difference lies in be equipped with the logical of multiple ellipses in the middle part of the cylindrical shape of each peripheral throttling element 3 for two embodiments and first embodiment
The through-hole 11 in hole 11, these ellipses is uniformly distributed along the circumferential direction of peripheral throttling element 3.
Embodiment 3
Figure 10 shows the rectification of 3rd embodiment according to the present utility model and the sectional view of flow measurement device, Tu11He
12 show the stereogram and sectional view of the orifice union of 3rd embodiment according to the present utility model respectively.
Include measurement pipe according to the rectification of the utility model 3rd embodiment and flow measurement device as shown in the figures above
8 and the orifice union in measurement pipe 8.Wherein, orifice union includes center throttling element 2 and multiple peripheral throttling elements 3.Center
Throttling element 2 is spindle, with isodiametric cylindrical central part.Peripheral throttling element 3 is cylindrical shape, the axial cross section of side wall
For spindle, and peripheral throttling element 3 has in the middle part of isodiametric cylindrical shape, and the side wall of peripheral throttling element 3 has certain thickness.It surveys
Buret 8 is cylindrical shape.Multiple periphery throttling elements 3 are sheathed on the outside of center throttling element 2, center throttling element 2, multiple peripheries successively
Throttling element 3 and measurement pipe 8 are coaxially disposed, between center throttling element peripheral throttling element adjacent thereto, adjacent peripheral throttling element
Between and measurement pipe peripheral throttling element adjacent thereto between be respectively formed annular fluid passage 1, wherein annular fluid passage
1a is near the side wall of measurement pipe 8, axis of the annular fluid passage 1b near measurement pipe 8.Along the axial direction side of center throttling element 2
To annular fluid passage 1 includes entrance contraction section, iso-cross-section section and export expansion section successively.It is with annular fluid passage 1a
Example, the head on head of the entrance contraction section by fusiform center throttling element and the peripheral throttling element with spindle axial cross section
Portion is formed, iso-cross-section section by center throttling element isodiametric cylindrical central part and peripheral throttling element isodiametric cylindrical shape
Middle part is formed, and export expansion section is formed by the tail portion of center throttling element and the tail portion of peripheral throttling element.Each annular fluid passage 1
It is inside equipped with support connector 9, support connector 9 plays fixed supporting role to center throttling element 2 and peripheral supports 3.
Multiple circular through holes (see Figure 11 and 12) are equipped in the middle part of the cylindrical shape of each peripheral throttling element 3, these circles are logical
Hole is uniformly distributed along the circumferential direction of peripheral throttling element 3.
It is equipped with high pressure pressure port 4 close to the arrival end of orifice union on the side wall of measurement pipe 8, in the side wall of measurement pipe 8
The centre position of the iso-cross-section section of upper annular fluid passage is equipped with low pressure pressure port 5.One end connection of high pressure pressure guiding pipe is supreme
Pressure port 4, the other end is pressed to be connected to the high pressure port of differential pressure transmitter 6, one end of low pressure pressure guiding pipe is connected to low pressure pressure port
5, the other end is connected to the low-pressure port of differential pressure transmitter 6.Difference transmitter 6 is connect with computer 7.
The application method and principle of rectification and flow measurement device are identical with the first embodiment according to third embodiment, herein
It repeats no more.
Embodiment 4
Figure 13 and 14 shows the stereogram and sectional view of the orifice union of fourth embodiment according to the present utility model respectively.
Fourth embodiment and 3rd embodiment are logical difference lies in multiple ellipses are equipped in the middle part of the cylindrical shape of each peripheral throttling element 3
Hole, these ellipse holes are uniformly distributed along the circumferential direction of peripheral throttling element 3.
Embodiment 5
Figure 15 and 16 shows the stereogram and sectional view of the orifice union of the 5th embodiment according to the present utility model respectively,
Figure 17 show the rectification of the 5th embodiment according to the present utility model and the annular fluid passage of flow measurement device etc. it is transversal
The sectional view of face section.
Difference lies in the shapes of measurement pipe, center throttling element and peripheral throttling element for 5th embodiment and first embodiment not
Together, and in order to ensure that fluid smooth flow, center throttling element and periphery throttling element carry out rounded corner processing respectively, to annular
The cross section of fluid channel is fillet rectangular-ambulatory-plane.
In the present embodiment, center throttling element is cylindricality, and peripheral throttling element is tubular, in the axis perpendicular to center throttling element
To each section on, the cross section of center throttling element is round rectangle, and the cross section of peripheral throttling element is fillet rectangular-ambulatory-plane,
Along the axial direction of center throttling element, center throttling element goes out including first entrance contraction section, the first equidimension section and first successively
Mouth expansion segment, peripheral throttling element include second entrance contraction section, the second equidimension section and second outlet expansion segment successively.In this reality
It applies in example, measurement pipe, peripheral throttling element, center throttling element are formed by the area satisfaction of the cross section of annular fluid passage or more
Formula (2).It in this case, can be according to determining z shown in Figure 17 at application formula (2)iValue, with improve calculate
Accuracy.
Each embodiment of the utility model is described above, above description is exemplary, and non-exclusive, and
And it is also not necessarily limited to disclosed each embodiment.Without departing from the scope and spirit of illustrated each embodiment, for
Many modifications and changes will be apparent from for those skilled in the art.
Claims (16)
1. a kind of orifice union, which is characterized in that including center throttling element and multiple peripheral throttling elements, the multiple periphery throttling
Part is sheathed on the outside of the center throttling element successively, and coaxial with the center throttling element, the center throttling element and its phase
It is respectively formed annular fluid passage between adjacent peripheral throttling element, between adjacent peripheral throttling element, along the center throttling element
Axial direction, the annular fluid passage successively include entrance contraction section, iso-cross-section section and export expansion section.
2. orifice union according to claim 1, which is characterized in that the center throttling element and the multiple periphery throttling
The axial length of part is equal, and axial end face is mutually aligned.
3. orifice union according to claim 2, which is characterized in that the center throttling element is hourglass shape, and with etc.
The cylindrical central part of diameter, the periphery throttling element is cylindrical shape, and mid diameter reduces to be formed in the middle part of isodiametric cylindrical shape,
The cylindrical central part of the center throttling element is equal with the axial length in the middle part of the cylindrical shape of the peripheral throttling element.
4. orifice union according to claim 2, which is characterized in that the center throttling element is spindle, and with etc.
The cylindrical central part of diameter, the periphery throttling element are cylindrical shape, and the axial cross section of side wall is spindle, and the periphery is saved
Flowing part has in the middle part of isodiametric cylindrical shape, the cylindrical shape of the cylindrical central part of the center throttling element and the peripheral throttling element
The axial length at middle part is equal.
5. orifice union according to claim 3 or 4, which is characterized in that in the middle part of the cylindrical shape of the peripheral throttling element
Equipped at least one through-hole.
6. orifice union according to claim 3 or 4, which is characterized in that the face of the cross section of the annular fluid passage
Product meets following formula (1), wherein axial direction of the cross section perpendicular to the center throttling element：
Wherein, i=1 ... N, N are the quantity of annular fluid passage；
SiFor the area of the cross section of the iso-cross-section section of i-th of annular fluid passage；
liFor the axial length of i-th of annular fluid passage；
viFor the flow velocity of the iso-cross-section section in i-th of annular fluid passage；
riFor the center radius of circle of the iso-cross-section section of i-th of annular fluid passage.
7. orifice union according to claim 1, which is characterized in that the center throttling element is cylindricality, the periphery section
Stream part is tubular, on each axial section perpendicular to the center throttling element, the cross section of the center throttling element
Cross section for rectangle, the periphery throttling element is rectangular-ambulatory-plane, along the axial direction of the center throttling element, the center throttling
Part includes first entrance contraction section, the first equidimension section and first outlet expansion segment successively, and the periphery throttling element includes successively
Second entrance contraction section, the second equidimension section and second outlet expansion segment.
8. orifice union according to claim 7, which is characterized in that the area of the cross section of the annular fluid passage is full
Sufficient following formula (2), wherein axial direction of the cross section perpendicular to the center throttling element：
Wherein, i=1 ... N, N are the quantity of annular fluid passage；
SiFor the area of the cross section of the iso-cross-section section of i-th of annular fluid passage；
liFor the axial length of i-th of annular fluid passage；
viFor the flow velocity of the iso-cross-section section in i-th of annular fluid passage；
ziFor the half of the catercorner length of the central rectangular of the iso-cross-section section of i-th of annular fluid passage.
9. orifice union according to claim 3, which is characterized in that the orifice union is for being set to pipe under test
Interior, the pipe under test is cylindrical shape, and the center throttling element, the multiple peripheral throttling element and the pipe under test are coaxial
Setting, the inner wall of the pipe under test are equipped with annular protrusion, to the pipe under test peripheral throttling element adjacent thereto it
Between also formed include entrance contraction section, iso-cross-section section and export expansion section annular fluid passage, in the pipe under test
It is equipped with high pressure pressure port close to the arrival end of the orifice union on side wall, close to the iso-cross-section section of the annular fluid passage
Equipped with low pressure pressure port.
10. orifice union according to claim 4, which is characterized in that the orifice union is for being set to pipe under test
Interior, the pipe under test is cylindrical shape, and the center throttling element, the multiple peripheral throttling element and the pipe under test are coaxial
It is arranged, also formation includes entrance contraction section, iso-cross-section section and goes out between the pipe under test peripheral throttling element adjacent thereto
The annular fluid passage of mouth expansion segment, high pressure is equipped on the side wall of the pipe under test close to the arrival end of the orifice union
Pressure port, the iso-cross-section section close to the annular fluid passage are equipped with low pressure pressure port.
11. orifice union according to claim 7, which is characterized in that the orifice union is for being set to pipe under test
Interior, the pipe under test is square tube shape, and the center throttling element, the multiple peripheral throttling element and the pipe under test are coaxial
Setting, the inner wall of the pipe under test are equipped with annular protrusion, to the pipe under test peripheral throttling element adjacent thereto it
Between also formed include entrance contraction section, iso-cross-section section and export expansion section annular fluid passage, in the pipe under test
It is equipped with high pressure pressure port close to the arrival end of the orifice union on side wall, close to the iso-cross-section section of the annular fluid passage
Equipped with low pressure pressure port.
12. a kind of rectification and flow measurement device, which is characterized in that including：
Measurement pipe；
According to the orifice union described in any one of claim 1-5 and 7, the orifice union is set in the measurement pipe；
Wherein, the center throttling element, the multiple peripheral throttling element and measurement pipe coaxial arrangement, the measurement pipe and its
Also formation includes that the annular fluid of entrance contraction section, iso-cross-section section and export expansion section is logical between adjacent peripheral throttling element
Road is equipped with high pressure pressure port on the side wall of the measurement pipe close to the arrival end of the orifice union, close to the annular flow
The iso-cross-section section in body channel is equipped with low pressure pressure port.
13. rectification according to claim 12 and flow measurement device, which is characterized in that set on the inner wall of the measurement pipe
Have annular protrusion, to also formed between the measurement pipe peripheral throttling element adjacent thereto include entrance contraction section, etc. it is transversal
The annular fluid passage of face section and export expansion section.
14. rectification according to claim 12 and flow measurement device, which is characterized in that the measurement pipe is cylindrical shape,
The area of the cross section of the annular fluid passage meets following formula (1), wherein the cross section is perpendicular to the measurement pipe
Axial direction：
Wherein, i=1 ... N, N are the quantity of annular fluid passage；
SiFor the area of the cross section of the iso-cross-section section of i-th of annular fluid passage；
liFor the axial length of i-th of annular fluid passage；
viFor the flow velocity of the iso-cross-section section in i-th of annular fluid passage；
riFor the center radius of circle of the iso-cross-section section of i-th of annular fluid passage.
15. rectification according to claim 12 and flow measurement device, which is characterized in that the measurement pipe is square tube shape,
The area of the cross section of the annular fluid passage meets following formula (2), wherein the cross section is perpendicular to the measurement pipe
Axial direction：
Wherein, i=1 ... N, N are the quantity of annular fluid passage；
SiFor the area of the cross section of the iso-cross-section section of i-th of annular fluid passage；
liFor the axial length of i-th of annular fluid passage；
viFor the flow velocity of the iso-cross-section section in i-th of annular fluid passage；
ziFor the half of the catercorner length of the central rectangular of the iso-cross-section section of i-th of annular fluid passage.
16. rectification according to claim 12 and flow measurement device, which is characterized in that further include high pressure pressure guiding pipe, low
Pressure pressure guiding pipe and differential pressure transmitter, one end of the high pressure pressure guiding pipe are connected to the high pressure pressure port, and the other end is connected to institute
The high pressure port of differential pressure transmitter is stated, one end of the low pressure pressure guiding pipe is connected to the low pressure pressure port, and the other end is connected to
The low-pressure port of the differential pressure transmitter.
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| CN201820263765.8U CN208059950U (en) | 2018-02-23 | 2018-02-23 | Orifice union, rectification and flow measurement device |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2019161716A1 (en) * | 2018-02-23 | 2019-08-29 | 南京亿准纳自动化控制技术有限公司 | Throttling component and rectification and flow measurement device |
| CN112546368A (en) * | 2020-11-30 | 2021-03-26 | 深圳市科曼医疗设备有限公司 | Differential pressure type flow sensor and breathing machine |
-
2018
- 2018-02-23 CN CN201820263765.8U patent/CN208059950U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2019161716A1 (en) * | 2018-02-23 | 2019-08-29 | 南京亿准纳自动化控制技术有限公司 | Throttling component and rectification and flow measurement device |
| CN112546368A (en) * | 2020-11-30 | 2021-03-26 | 深圳市科曼医疗设备有限公司 | Differential pressure type flow sensor and breathing machine |
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