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FlatFlangeWafer Balance Flowmeter

Integrated Balance Flowmeter

WeldedFlangeWafer Balance Flowmeter

2.MeasurementPrinciples

The traditional throttling device has been greatly improved by the multi-hole balance orifice,and the throttling principle has been changed from edge throttling to multi-hole balanced throttling.The sensor isa multi-hole disc throttle rectifier,which is installed on the cross section of the pipe.The size and distribution of each hole are customized based on the unique formula and test data,which is called function hole.When the fluid passes through the disc function hole,the fluid will be balanced and adjusted,and the vortex will be minimized to form an approximate ideal fluid.The stable differential pressure signal will be obtained by taking the device,and the volume flow and mass flow will be calculated according to Bernoulli equation.

The calculation formulaisas follows:

{ \bf q } _ { { m } } - mass flow ( { {kg / s } ) } （20号
（204号 \mathsf { q } _ { { v } } - volume flow under working conditions ( { m } ^ { 3 } / { s } ) 门
\triangle \mathfrak { p } - differential pressure (Pa)
ε-expandability coefficient, \scriptstyle { \varepsilon = 1 } for liquid; \varepsilon { < } 1 for
compressible fluids such as gasand steam
β - equivalent diameter ratio
C -discharge coefficient
D- pipe inner diameter(m)

3.ProductFeatures

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1.High measurement accuracy

With the multi-hole symmetrical structure,it can be used for balanced rectification of the flow field, thus reducing the vortex,vibration and signal noise, improving stability of the flow field greatly,and increasing the linearity by 5\~10 times compared with traditional throttling devices.

2.Short straight pipe section

The sensor can stabilize the flow field and restore the pressure twice as fast as the traditional throtling device,which reduces the requirements for straight pipe section significantly.Generally, the straight pipe section shall be 2D in the front part and 2D in the rear part.

3.Wide range ratio

It is 4:1 under normal circumstances,and can reach 10:1 if appropriate parameters are selected.

4.Low permanent pressure loss

The balanced design reduces the formation of vortex and turbulent friction,and reduces the kinetic energy loss.

The permanent pressure loss is about 1/3 of that of conventional throttling devices when the differential pressure value is the same.

5.Resistance to dirt and low risk of blockage

The multi-hole and symmetrical design reduces the formation of vortex and the turbulent friction, reduces the dead zone of flow field,and ensures that the dirty medium passes through the function hole smoothly.Therefore,it can be used to measure various dirty media,such as coke oven gas,blast furnace gas, residual oil,recycled oil,coal water slurry,etc.

6.Wide applicable scope

It has a wide measuring range,which covers various gases,liquids and steam.The fluid conditions can range from deep low temperature to supercritical state,with the process temperature up to 8 5 0 ^ { \circ } { C } and the maximum working pressure up to 4 2 { M P a } ：

7.Low signal-to-noise ratio

It is generally less than 1 % .The semi-annular voltage-sharing structure of the multi-hole orifice reduces fluctuation of the output signal,thus reducing the signal-to-noise ratio and eliminating the measurement error caused by signal fluctuation.

4.Main technicalparameters

5.Installationrequirements M

5.2Installation of horizontal pipeline (as shown in the following figure):

When liquid medium is adopted,the pressure port and transmiter shall be installed within a range of 4 5 ^ { \circ } { C } below the pipeline.When gas medium is adopted,the pressure port and transmitter shall be installed within arange of 4 5 ^ { \circ } { C } above the pipeline.When steam medium is adopted,the pressure port shall be horizontal and a condensing device shall be installed.

a When the measured fluid is liquid

b When the measured fluid is gas

5.3Installation of vertical pipeline (as shown in the following figure):

When liquid medium is adopted,the transmittr shall be installed below the pressure pipe.When gas medium is adopted,the transmitershall beinstalledabove the pressurepipe.Whensteammediumisadopted,the pressureport shall be horizontal and a condensing device shall be installed.

When the measured fluid is gas

When the measured fluid is liquid

When the measured fluid is steam

6.InstallationDimension Diagram

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6.1.Flange clamped multi-hole orifice (balanced orifice)

Note:The above dimensions are for reference only.

SIC New Generation DFX-type Wedge Flowmeter

Application

·Measure the flow of gas,steam and liquid ·It is suitable for polluted environment and medium where fluid is easy to be blocked.Especially, it has its unique advantages in the flow measurement of fluids containing solid suspensions such as mud,sandy crude oil,ore pulp,residual oil and heavy oil.

Advantages

Effective measurement of any clean or dirty fluid Rough,high viscosity fluid Liquid,gas,steam,multi-phase flow High and low temperature fluids ·For low Reynolds number measurement,the square root relationship between flow and differential pressure can still be maintained when ReD \scriptstyle = 3 0 0

·Bi-directional flow measurement ·Extremely short upstream and downstream pipelines,which shall be at least 5D in the front section and 3D in the rear section

·High accuracy,which is within ± 1 % of indication

·State-of-the-art non-cutting pipe wedge welding technology

·Provide calcium carbide wear-resistant wedge type

·Provide multi-pressure tap wedge type

1.ProductIntroduction

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Wedge flowmeter is a sidewall contracting throttling device.The detection element of the wedge flowmeter is a wedge,which is a V-shaped throttling element,with its smooth top angle facing downwards. This is conducive to the smooth passage of liquid containing suspended particles or viscous liquid without retention on the upstream side of the throtling element.

2.Working principle

Wedge flowmeter is a flowmeter based on the principle of differential pressure.Differential pressure \boldsymbol { \triangle } \mathfrak { p } will be generated upstream and downstream of the wedge throttling element when the measured fluid passes through the element.The flow is proportional to the square root of the differential pressure.Therefore, the flow can be calculated by measuring the pressure difference ahead of and behind the wedge throttling element.

Flow calculation equation:

（204号 { \bf q } _ { { m } } -mass flow ( { {kg / s } ) } （20 { \mathfrak { q } } _ { { v } } - volume flow ( { m } ^ { 3 } / { s } ) C- efflux coefficient ε-expandability coefficient （ β \mathbf { S } _ { \imath } - diameter ratio, - brotligarea { β } = { { d } } / { { D } } ( \mathbf { m } ^ { 2 } ) ， { \bf \partial } \mathsf { \Pi } ^ { \mathsf { D } ; } = / { { \bf S } _ { 1 } } { π * { \bf \Pi } \left( { \bf D } / 2 \right) ^ { 2 } } = { \bf β } ^ { 2 } （2 \rho - density of the measured medium under working condition ( {kg / m } ^ { 3 } ) 1 \triangle _ { \mathfrak { p } } - differential pressure (Pa) D-pipe inner diameter (mm) Calculation of S1: S=[rl-x(r-h)] x=2√h(2r-h) l=0.01745ra a=2arcos(1-) S1 1

3.ProductFeatures

It is suitable fora wide range of media,especially for the measurement of mud,coal tar pitch,suspended coal-water and other high viscosity fluids.

It can be used to measure corrosive media,and is equipped with the diaphragm-type double-flange differential pressure transmitter. Corrosive media cannot enter impulse pipe or differential pressure transmitter. The instrument can be used to measure corrosive media if the wedge throttling element is processed with corrosion-resistant materials.

It is characterized by simple structure and convenient installation,use and maintenance.For the separated wedge flowmeter,its measuring range can be expanded or changed by replacing the wedge.

·The flow rate increases when the fluid approaches the wedge,and the high-speed fluid can clean the wedge and the inner wall of pipe,and will not adhere to or precipitate on the throttling element.

·The wedge sensoris ofV-shaped design,and the top of the V-shaped sensor is an arc ofR3-R10,so that its wear resistance can be increased greatly,and the size and throttling area of the throttling element can remain unchanged fora long time.There is no movable part or vulnerable part,so that the measurement accuracy,stability and reliability of instrument can be maintained for a long time.

·The pressure loss is low,which is only 1/2-1/3 of that of the orifice.

·The integrated structure design makes it possible to display temperature,pressure and differential pressure on the LCD screen at the same time.So that it is unnecessary to use the impulse pipe, blockage and leakage caused by the pipe can be avoided,and the installation is convenient.

·Wedge sensors can be configured by any transmitter designated by the user to output (4-20) mA, differential pressure,or flow signals.

4.Maintechnicalparameters

5.Structure type

It can be divided into the integrated type and separated type according to the connection form of wedge flow sensor and differential pressure transmitter.

5.1 Integrated type

The wedge flow sensor is integrated with the differential pressure transmitter,which can be easily disassembled,replaced in use,changed in termsof the range,and connected with the pipe through thread or flange.

5.2 Separated type

The separated pressure tap is T-shaped,and the positive and negative pressure taps are arranged upstream and downstream the throttling element respectively.The distance to the upstream and downstream pressure taps is equal. The measuring tube equipped with the throttling element can be replaced to change the range.The diaphragm-sealed differential pressure transmitter is adopted to separate the measured medium from the impulse pipeline and transmitter,so it can be used for the measurement of dirty medium.

T-shaped interface T-shaped interface TiHI Wedge

5.3 Pressure tapping mode

The pressure tapping modes include nozzle pressure tapping and flange pressure tapping according to the actual service conditions.

As shown in the figure:

Flange pressure tapping

Conduit Pressure Tapping (Nozzle Pressure Tapping)

5.4Jacketed wedge flowmeter

Jacketed pipes are added outside the main measuringpipes,which are generallyused for steam tracing to ensure the stability of medium temperature.

Jacketed WedgeFlowmeter

6.StrongWear-resistant Structure

It is specially designed for the measurement and control of black water and grey water in the coal chemical gasification section.Due to the great abrasion and high temperature of black water and grey water,our wedge flowmeter adopts the integral hotcast tungsten carbide technology to improve the abrasion resistance greatly.The wedge flowmeter is preferred in the black water and grey water measurement control section because its structure is particularly suitable for measuring liquids with high particle concentrations.

6.1 Integral sintered wedge shall be adopted fordiameter≤DN150

6.3Flange pressure tapping is adopted for wedge flowmeter under special working conditions,and the three pressure tapping methodscanbe combined

6.2 Sintered tungsten carbide plates are used for the wedge throttling element withadiameter≥DN200

Length L may be greater than the size in the table if the pressure rating is greater than the value in the table or the pressure tap is greater than or equal to DN80.H will be increased 2 0 ~ { { \mm } } if the pressure tapping flange is greater than or equal to

8.1Selectionof sensordiameter

The nominal diameter of the selected sensoris the same as that of the connected process pipe.This option is convenient for installation.

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Itisrecommendedthattheusershouldtryto selectthewedgeratioand flowrange intheabove tableinorderto ensure the measurementaccuracyand timely deliveryof the product.

8.2 Selection of flanges

The wedge flow sensor shall be connected with the process pipeline by flanges,including flanges complying with national standards and standards of the Machinery Department.The US ANSI standards, Germany DIN standards and relevant domestic industry standards can also be adopted according to the requirements of different industries.If companion mounting flangesare required,please specify them at the time of ordering.

8.3Workingenvironment

Requirements of flowmeter for external

environment:

There must be sufficient installation space around the flowmeter in order to facilitate installation and maintenance.

8.4Precautions

(1）The wedge flow sensor is generally not equipped with an external flange or root valve when leaving the factory,which shall be explained during selection if necessary.

(2）Special requirements shall be explained at the time of ordering.

9.Installation requirements

(1)Flow direction

The flow direction arrow on the sensor housing is the forward flow direction specified by the manufacturer.When installinga flowmeter,the user shall ensure the flow directionmark onitisconsistent with the field process flow direction.

(2)Installation direction

·The sensor can be installed on horizontal and vertical pipes for use.

·Fluid shall flow from bottom to top when the sensor is installed ona vertical pipe.The measurement error caused by the height of positive and negative pressure taps not on the same horizontal plane shall be corrected as necessary.

·During installation,the inner wall of the pipe shallbe smooth,cleanand freeofadhesive substances. ·The sealing gasket shall not protrude into the flowmeter pipeline during the installation of flange.

·The flow regulating valve is installed downstream of the flowmeter sensor.

·The installation of differential pressure signal pipeline shall meet the on-site pipeline installation requirements according to the nature of the measured medium,and relative position of the wedge sensor and the differential pressure transmitter.

·For the wedge flowmeter installed on horizontal or inclined process pipeline,the drain hole (if any) shall be directly above the pipeline if liquid medium is adopted,and shall be directly below the pipeline of gas or steam is used.

(3）Requirements for straight pipe section

When the differential pressure instrument is used for flow measurement, the fluid is required to reach a fully turbulent condition when flowing through the differential pressure meter,so as to ensure the measurement accuracy.Therefore,a long enough straight pipe section shall be provided ahead of the differential pressure instrument.Therequirements for the shortest straight pipe section upstream of the wedge flowmeter are shown in the following table:

SICNew GenerationDFJ-typeRectangularFlowmeter

Application:

·Measurement of gas,steam and liquid. ·High viscosity fluid,high friction (containing solid particles) fluid,corrosive fluid and other media under harsh working conditions,such as oil slurry, black water,residual oil,heavy oil,ore pulp and sewage,are widely used in coal chemical industry, polysilicon,and power industry, etc. ·Measurement under micro-pressure and lowpressure loss conditions,such as air supply from electronic factory and heating furnace.

Advantages

·Many media can be measured ·High accuracy ·The rectangular flowmeter is not calibrated to
an accuracy of 1 % ，while the measured value can be
calibrated to an accuracy of 0 . 2 5 % if necessary. ·Wide range ·Long service life ·Small pressure loss ·Small installation space,and short front and rear
straight pipe sections required ·Integrated and simplified installation

Comparison with wedge flowmeter

·Long service life,which is 3\~4 times that of wedgeflowmeter ·Small pressure loss,which is 1/2\~1/3 of that of wedge flowmeter ·Small installation space,requiring a front straight section shorter than thatofwedge flowmeter ·High precision,which can be calibrated to Grade 0.25 ·Wide range ratio,which is 2\~3 times that of wedge flowmeter

Disadvantages

·High cost and long manufacturing cycle ·Real flow calibration required

1.ProductOverview

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2.Workingprinciple

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Rectangular flowmeterisathrottling element that generates differential pressure signal.The flow of fluid can be measured accurately by the relationship between differential pressure signal and flow according to the hydrodynamic equation.The throttling blockof a rectangular flowmeter has some characteristics of the throttling wedge of a wedge flowmeter and most characteristics of a venturi flowmeter.

The rectangular flowmeter has the same flow section as the wedge flowmeter,and adopts calculation formula of the wedge flowmeter:

qm-mass flow { (kg / s ) } （2号 （20 { \sf q } _ { { v } } - volume flow ( { m } ^ { 3 } / { s } ) 1 C -discharge coefficient ε-expandability coefficient （204号 β m - diameter ratio, -trotliaa { β } = { { d } } / { { D } } 。。 m = / { { S } _ { 1 } } { π * { \Omega } \left( { D } / 2 \right) ^ { 2 } } = { β } ^ { 2 } { S } _ { { \ell _ { 1 } } } ( \mathbf { m } ^ { 2 } ) p-density of the measured medium under working condition ( {kg / m } ^ { 3 } ) 0 \triangle \mathfrak { p } - differential pressure (Pa) D- pipe inner diameter (mm) Calculation of S1;

3.ProductFeatures

Generally,the measuring elements of flowmeters are not resistant to high-pressure wear. The current wedge flowmeter can be used to measure fluids with low flow rate,low Reynolds number and high viscosity,and is far superior to other measuring elements when being used in highly abrasive fluids, butitswearresistance islimited.The throttling block of rectangular flowmeter is obtuse-angled or circular arc,without wedge-shaped edges.The fluid flows from contraction section to the throat smoothly,which can reduce wear greatly.At the same time,the rectangular flowmeter adopts a streamlined throttling channel and a throat ofappropriate length.The throat plays a role of rectification and controls the fluctuation of fluid effectively. In addition,the rear pressure recovery section extends this streamlined flow channel,so that no vortex and vibration will be generated inside the whole flowmeter,thus avoiding wear caused by vortex. The rectangular flowmeter can be used for 3 consecutive years without changing the measurement accuracy,and its service life is more than 4 times that of the wedge flowmeter.

At the same time,the throttling block of rectangular flowmetermaybe solid and hardened,and calcium carbide or stellite alloy can be welded on the surface.The inside of pipeline may also be hardened and preservative treated,and the flowmeter can be designed as a corrosion-resistant structure (lined with PTFE,ceramic or rubber).

·Small pressure loss and great differential pressure

General throttling devices,such as wedge flowmeters,are used to measure flow by throttling and generating differential pressure with throttling blocks, and the pressure of throttling elementis freelyrestored based on the principle of hydromechanics,in which case the pressure loss is often great.The higher the measurement accuracy, the greater the range ratio,and the greater the pressure loss,which is generally 3 0 % { ~ } 6 0 % of the measured differential pressure.The structure of rectangular flowmeter is similar to the head recovery section of the venturi flowmeter,which can restore the pressure to the maximum extent,and the pressure loss is 1 5 % { ~ } 2 5 % of the measured differential pressure.

The rectangular flowmeter is widely used in the measurement of micro-pressure and low-pressure loss conditions,such as air supply and suction of power plants and air supply of heating furnaces,because the throat center is used for pressure tapping,and a differential pressure much higher than that of other flowmeters can be obtained according to Bernouli equation due to the maximum flow rate in the center.

·High accuracy

The rectangular flowmeter is not calibrated to an accuracy of 1 % ，while the measured value can be calibrated to an accuracy of 0 . 5 % { - 0 . 2 5 % } if necessary.

RectangularBlock

4.Maintechnicalparameters

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5.Structure type

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·There are three types of rectangular flowmeters: split type, integrated type and the type with temperature compensation sensor.

·There are two connection modes for pipelines: flange connection and direct butt welding.
·Pressure tapping mode: flange pressure tapping mode and impulse pipe pressure tapping mode.

Structure DiagramofRectangularFlowmeter

Users are recommended to select the conventional dimensions in the above table,and refer to the quotation forother dimensions.

7.Installationrequirements

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(1）Flow direction

The flow direction arrow on the sensor housing is the forward flow direction specified by the manufacturer. When installing a flowmeter, the user shall ensure the flowdirectionmark onitis consistent with the field process flow direction.

(2)Installation direction

·The sensor can be installed on horizontal and vertical pipes for use.

·Fluid shall flow from bottom to top when the sensor is installed ona vertical pipe.The measurement error caused by the height of positive and negative pressure taps not on the same horizontal plane shall be corrected as necessary.

·During installation,the inner wall of the pipe shall be smooth,cleanand free ofadhesive substances.

·The flow regulating valve is installed downstream of the flowmeter sensor.

·The installation of differential pressure signal pipeline shall meet the on-site pipeline installation requirements according to the nature of the measured medium,and relative position of the rectangular sensor and the differential pressure transmitter.

·For the wedge flowmeter installed on horizontal or inclined process pipeline,the drain hole (if any) shall be directly above the pipeline if liquid medium is adopted,and shall be directly below the pipeline of gas or steam is used.

(3）Requirements for straight pipe section

To make sure that the flow coefficient is a linear constant within the specified Reynolds number range, a large number of experimental studies and investigations have been performed on the impact of installation in the process of development,proving that the downstream straight pipe section is unnecessary for the rectangular flowmeter,and the minimum upstream straight pipe section depends on the disturbance to the fluid flow state caused by the specific design of upstream process pipeline.

Note:

1.The length of the shortest straight pipe section is expressed as a multiple of the diameter Dof the process pipe. 2.The roughness of the upstream straight pipe section measured from the plane of the upstream pressure tap shall not exceed accuracy of the smooth pipe commercially available (about { K } / { D } \le 1 0 ） 3.Values without parentheses are "zero additional uncertainty".Values within parentheses are" 0 . 5 % （204号 additional uncertainty". 4.The bending radius of elbow is equal to or greater than the pipe diameter. 5.Pipe fitings or other chokes located at least4 times the throat diameter downstreamofthe throat pressure tap shall not affect the measurement uncertainty.

SICNew Generation DFV-type V-cone Flowmeter

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1.ProductOverview

V-cone flowmeter is a differential pressure flowmeter and has the same working principle as the standard throttling device,which is based on fluid continuity equation and Bernoulli equation.When the fluid flows through the V cone installed coaxially with the pipe,the local contraction of the flow accelerates the fluid rate,which reaches its maximum value at the maximum diameter of the V cone,so that the static pressure drops,forming a low pressure end at downstream end of theV cone.So that a differential pressure \triangle \mathbf { P } is generated ahead of and behind the V cone.The positive differential pressure is the static pressure PH measured before the upstream fluid contracts.The negative differential pressure is the static pressure PL measured at the center of downstream end face of the { ~ v ~ } cone.Therefore,the flow of fluid can be measured by measuring the differential pressure \triangle \mathbf { P } generated ahead of and behind the cone according to the relationship between the square root of differential pressure and the flow of fluid.

1.1 Application

·Measure the flow of gas,steam and liquid

·The flowmeter is designed as a fluid sweep structure,which is impossible to intercept any entrained gas,liquid or solid pollutants in the fluid.It isvery suitable for flowmeasurement ofdirty fluids, such as coke oven gas and wet gas,especially blast furnace gas.It has a self-cleaning effect and the impulse pipe is not easy to be blocked.

1.2 Advantages

It can be used for effective measurement of any clean or dirty fluid,such as liquid,gas,steam,and high temperature and low temperature fluid

·Wide range ratio of 4:1 to 10:1 ·Self-rectification function,requiring only extremely short straight pipe section ((l\~3)D in the front part and 2D in the rear part)

·Self-cleaning function,so it is capable of measuring dirtyand easily scaled fluids,and is suitable for blast furnace gas and other media with many impurities

·High accuracy,which is within ± 1 % of indication

·Self-protection function,so that key parts of throttling elements will not wear,and long-term stable operation can be ensured

2. Working principle

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3.InstrumentCharacteristics

The flow formulais as follows:

qm-mass flow \left( { {kg / s } } \right) （204号
qv-volume flow under working conditions ( { m } ^ { 3 } / { s } ) \triangle \mathfrak { p } - differential pressure (Pa)
ε-expandability coefficient, \scriptstyle { \varepsilon = 1 } for liquid;
\scriptstyle { \varepsilon < 1 } for compressible fluids such as gas and steam β - equivalent diameter ratio
C-discharge coefficient
D- pipe inner diameter (m)

·High accuracy

The accuracy of primary element of V-cone flowmeter reaches 0 . 5 %

·High repeatability

The repeatability of primary element of the Vcone flowmeter reaches 0 . 2 5 % （20

·Low requirements for installation of straight pipe section

The special structure of V-shaped cone can weaken the convex shape in the velocity distribution and achieve the characteristic of rectification.Itis this self-rectification characteristic that greatly reduces the requirements for the front and rear straight pipe sections. The section is generally (2\~3)D long upstream and (O\~1)D downstream.

·Low pressure loss,which is only 60 % of the orifice pressure loss.

·Signal stability

The β value can remain unchanged for a long time and long-term accurate measurement can be ensured.

Only high-frequency and low-amplitude small Vortices will be generated downstream of the V-cone due to its special shape.In this way,on the one hand, the differential pressure signal generated is relatively stable,and on the other hand,the sensitivity to small signals is higher than that of the central contracting throttling device (such as orifice),so that high measurement accuracy and stability can still be ensured atlow flow and low differential pressure.

·Long-term stability

Due to structural characteristics of the V-cone itself,the flow rate in the center reduces and that near pipe wall increases gradually when the fluid approaches the V-cone,which will lead to the following results:

a.No impurity entrained in the fluid can be intercepted,thus achieving the effect of self-cleaning.

b.Aboundary layer forms around theV-cone,and the fluid will be led away from the edge of the cone tail as the fluid flows through the V-cone.This selfprotection function reduces the wear caused by dirty medium,decreases the geometric deformation of Vcone greatly,ensures the stability of discharge coefficient ina long time,and increases the service life of flowmeter.

Rectification EffectofV-shaped Inner Cone

·The integrated structure design makes it possible to display temperature,pressure and differential pressure on the LCD screen at the same time.So that it is unnecessary to use the impulse pipe,blockage and leakage caused by the pipe can be avoided,and the installation is convenient.

·V-cone sensors can be configured by any transmitter designated by the user to output (4-20) mA, differential pressure,or flow signals.

·The V-cone has the function of self-mixing.The non-homogeneous phase fluid will mix automatically and become an average-velocity fluid when flowing through the V-cone,thus achieving effective flow measurement.The instrument is calibrated and delivered one by one on the standard device to ensure the measurement accuracy.

RectificationEffectofInnerCone

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4.Maintechnicalparameters

5.Structure type

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The connection forms between the V-cone flow sensor and the process pipeline are mainly as follows:

(1)Flange connection type

(2) Direct welding type

(3)Flange clamping type

6.InstallationDimensionof M V-coneFlow Sensor

(1)Flange connection type

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7.Installation requirements

Flowdirection

The flow direction arrow on the sensor housing is the forward flow direction specified by the manufacturer.When installing a flowmeter, the user shall ensure the flow direction mark on it is consistent with the field process flow direction.

Installationdirection

Sensors can be installed horizontally or vertically.

When the sensor is installed on a vertical pipe, the measurement error caused by the height of positive and negative pressure taps not on the same horizontal plane shall be corrected as necessary.

Requirements for straight pipe section

Generally,the front straight pipe section is (5\~10)D,and the rear straight pipe section is (2\~3)D.

Selection of installation position

\bigstar represents the installation position recommended

☆represents the installation position not recommended

Liquid InstallationPosition

Gas and Steam Installation Positions

8.PrecautionsforUse

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(1）Before using a new V-cone flowmeter or restarting a V-cone flowmeter which has been out of service for a period of time,check the pressure tapping pipeline for blockage and leakage.When liquid medium is adopted,fill the pressure tapping pipeline with clean water or other impulse liquids,and discharge the gas mixed in the pipeline.When gas mediumis adopted,discharge the accumulated liquid in the pipeline.

(2）It is recommended to provide a settler or isolator during the measurement of fluids containing suspended solids or dirt.The pressure tapping pipeline and sewage outlet shall be located properly to achieve the purpose of sewage discharge.

Promptforhighproductoperationrisks

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Duetothespecial structure the /-coneflowmeter maybesubj fallingoffdueto externa temperature，high pressu ammereffectand fatigue O maintain 1 regularl operationrisk

9.FluidsSuitable for Measurement:

M (1) Gas

Gas: coke oven gas,blast furnace gas,city gas

Natural gas: including natural gas with a moisture content of greater than 5 % （204号

Various hydrocarbon gases:alkane gases,olefin gases,etc.

Various pure gases:hydrogen,nitrogen, oxygen, etc.

Corrosive gas:wet chloride gas,etc.

Air: including air containing water and dust, compressed air, etc.

Flue gas: flue gas discharged from various boilers and heating furnaces

(2）Steam: saturated and superheated steam

(3)Liquid oil:crude oil,fuel oil,aqueous emulsified oil,diesel oil,hydraulic oil,etc.

Water: raw water,drinking water,production water,sewage,etc.

Various aqueous solutions:acid,alkali,saline solution, etc.

Organic chemicals:methanol,ethylene glycol, xylene,etc.

(4）Special fluids
Oil + HC gas ^ + sand
Aerated water; { H } 2 { O } + { N } 2 + air; _ { { H } 2 { O } + { C O } 2 } ,etc. \* Refer to Page PO2 for the type spectrum

SIC New Generation DFB-type SDB Averaging Pilot-tube Flowmeter

1. Introduction

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The averaging pitot-tube probe is the measuring element of sic-de-ba (SDB） averaging pitot-tube flowmeter,which is a new differential pressure flow measuring element developed based on the early pitottube velocity measuring principle.SDB flow sensors combined with differential pressure transmitters are used to measure gas,liquid,and steam flows in circular and rectangular pipes.Compared with other flow instruments,this flowmeter has a series of outstanding advantages such as long-term stability，good repeatability,simple installation and maintenance, small permanent pressure loss,low operation costs, significant energy saving，simple and reliable structure,etc.It is especially widely used in energy, environmental protection and other metrological testing.Therefore,SDB averaging pitot-tube flowmeter is widely used in electric power,metallurgy, petroleum,chemical industry,light industry,coal and urban public utilities.

Application

·Measure the flow of gas and liquid ·Be mainly used in power industry,metallurgical industry,water treatment and chemical industry ·Be applicable to the measurement of hightemperature and high-pressure liquid,air volume of large and medium-diameter pipes,and flue gas pipes ·Be applicable to the measurement of largediameter gases such as blast furnace gas,coke oven gas,converter gas and cold air of blast furnace hot stove in the metallurgical industry

Advantages

It can be used for effective measurement of any clean or slightly dusty fluid,such as liquid,gas,and high temperature and low temperature fluid

·Stable and good measurement signals ·Intrinsic anti-blocking design of probe ·Upstream and downstream pipelines,which
shall be atleast 7D in the front section and 3D in the
rear section ·High accuracy,which is within ± 1 % of

indication ·Wide measuring range up to 3:1 to 10:1 ·High-strength monolithic dual-cavity structure
ofprobe ·Being able to be inserted and pulled out online,
which is convenient for maintenance ·Integrated structure,which is easy to use,check
and troubleshoot

2.Working principle

The SDB flow sensor is inserted into the pipe,a high-pressure distribution area is generated in front of the probe according to the fluid continuity equation and Bernoulli's principle when the fluid flows through it,and the pressure in the high-pressure distribution area is slightly higher than the static pressure of pipe. When the fluid flows through the probe,it is split into two streams to flow through the averaging pitot-tube probe.In this case,the fluid speeds up,and a lowpressure distribution area is generated behind the probe,with a pressure slightly lower than the static pressure of pipe.The fluid flow is accurately measured bymeasuring the pressure difference \triangle \mathbf { P } between the average positive pressure PH in the high-pressure area and the average negative pressure PL in the lowpressure area.

Flow calculation equation:

qm-mass flow M(kg/s) qv- volume flow ( { m } ^ { 3 } / { s } ) （204号 K-flow coefficient ε-expandability coefficient ρ -density of the measured medium under working condition ( {kg / m } ^ { 3 } ) \triangle _ { \mathfrak { p } } - differential pressure (Pa) D-pipe inner diameter(mm)

3.Features

·Unique profile shape,which can realize high flow range ratio ·Double-averaging function,which improves the accuracy ·Integral monolithic dual-cavity structure,which provides the best strength ·Suitable pipe diameter: 2 0 0 {mm } to 6 0 0 0 {mm } ·Being suitable for the pipe with square or rectangular section ·Being provided as a hot tap,which can be inserted into the pressure pipe ·Optional direct-mounting transmitter layout ·Zero coefficient drift,which ensures long-term stability · Small permanent pressure loss,which is only 5 % of that of the orifice

4.Main technicalparameters

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5.1Structuralcharacteristics of bullet-shape SDB

·The streamlined probe design minimizes the traction force and fixes the separation point between the fluid and the probe to ensure the most stable differential pressure signal.

·The high-strength probe has an integrated dualcavity structure to avoid intermittent leakage,ensure long-term accuracy and improve upper range limit of the probe.

·Multiple groups of pressure tapping holes truly reflect the average flow rate of fluid,and make the signal more accurate.

·The unique position of low-pressure tapping hole not only prevents the hole from being blocked effectively,but also prevents the hole from being affected by vortex,making the low-pressure signal more stable and accurate.

·The probe surface is roughened,and the boundary layer of fluid on the probe surface is in a turbulent state,so that the probe can still obtain stable and accurate signalsat low flow rates.

5.2Structuralcharacteristics of diamond-shape SDB

(1）Enlarged sensor.The differential pressure value generatedat the same flowrateisslightlyhigher than that of bullet-shape sensor,and it is suitable for the flow measurement of low static pressure and low differential pressure fluids.

(2)Static pressure holes are located on both sides of the backflow surface to avoid the direct influence of vortex.The number of static pressure hole isincreased from1 to 6\~8 on each side,and the hole diameteris increased from \scriptstyle \Phi 3 ~ 4 to \boldsymbol { \Phi } ^ { 1 0 } ,which reduces the probability ofblockage greatly.

It can be widely used in the measurement of gases with high dust content (such as blast furnace gas,coke oven gas,converter gas,sintering flue gas,dust removal gas and flue gas).

(3）High-temperature averaging pitot-tube flow sensor.

It is suitable for measuring the flow of high temperature liquid,gas,water steam and other media.

(4）High-strength averaging pitot-tube sensor.

Compared with the traditional averaging pitottube sensor,the high-strength averaging pitot-tube flow sensor is characterized bya larger detection rod whose diameter is increased from \boldsymbol { \Phi } 2 8 to 60,larger pressure tapping hole whose diameter is increased from\varphi 4to\boldsymbol { \Phi } ^ { 1 0 }，greater number of 8~16,greater differential pressure (increased by3 0 \% { \sim } 4 0 \%$ ，more stable measurement, higher accuracy(up to Grade 0.5), wider range ratio (usually 1:12,and up to 1:15),and longer period ofblockage in dirty gas.

Fluid direction ↑

6.Producttype

6.1 The bullet-shape SDB averaging pitot-tube flowmeteris divided into the following four types according to the connection mode:

6.2 Product type

7.OverallDimensionsof Bullet-shape Sensor

Ferrule type/ferrule type with double-sided supporting(SDB-R/SDB-RS)

Threaded connection and spring-locked type (SDB-SS)

Threaded connection and online type (SDB-HS)

Flange connection type/flange connection type with double-sided supporting(SDB-F/SDH-FS)

Note:D refers to pipe inner diameter

9.Installationrequirements

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9.1Installation environment

The installtion environment is divided into shutdown installtionand online installation according to the structure of SDB products.

9.2Requirements for straight pipe section

SDB averaging pitot-tube flowmeter is a plug-in flowmeter.The flow in the tube shall be ina nearly fully developed turbulent state in order to make sure that the total pressure measured in several inspection holes in diameter direction of averaging pitot-tube can fully reflect the velocity distribution in the tube.

Therefore,when there is no rectifier,the length of front and rear straight pipe sections shall not be less than 7D and shall be 3D respectively.Such requirements are proposed mainly to ensure a higher measurement accuracy. If the requirements are not met,the accuracy of the averaging pitot-tube will be reduced and the tube should not be used for direct measurement and trade accounting.

However,the measurement accuracy of SDB averaging pitot-tube is ± 5 % when the current straight pipe section is 2D long.Satisfactory results can still be achieved when it is used for industrial control systems.

9.3 Installation position

The interference of pipe layout to flow can affect the measurement accuracy,so it is important to install the SDB averaging pitot-tube flowmeter properly. Please carefully read the following standard operations before selecting the installation position.

The flow direction arrow marked on the sensor is the forward flow direction specified by the manufacturer.When installing an instrument,the user shall make sure that the flow direction arrow on the sensor is consistent with the field process flow direction.

9.3.1 Influence of installation position on accuracy

The interference of the pipe layout to the flow can affect the accuracy of the measurement,so it is important to properly install the averaging pitot-tube flowmeter. Please carefully read the following standard operations before selecting the installation position.

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TheflowdirectionarrowmarkedontheSDB averaging_pitot-tubeflowmeter sensorisa forward flowdirectionspecifiedbythe manufacturer,whichshallbeconsistentwiththe fluiddirectioninthe field pipelineduringthe installationofinstrument.Theincludedangleof theaxisdirectionofthe pipeiswithin ± 3 ^ { \circ }

Installation of horizontal pipe

Installation for gas

Installation for liquid/steam

Installation of vertical pipe (1）Horizontal pipe

Installation for liquid/steam

Installation for gas

·For measurement of the gas medium,it is recommended that the SDB flow sensor be installed above the pipe,so that the condensate in the impulse pipe can flow back into the pipe.If the SDB flow sensor is installed below the pipe,a blowdown valve shall be installed.

·For measurement of the liquid medium,it is recommended that the SDB flow sensor be installed below the pipe,so that bubbles can flow back into the pipe.

If the SDB flow sensor is installed above the pipe, avent valve shallbe installed.

·For measurement of the steam medium,it is recommended that the SDB flow sensor be installed below the pipe.

(2）Vertical pipe

·For vertical pipe,the SDB averaging pitot-tube maybe installed in any orientation within 3 6 0 ^ { \circ } around the vertical pipe.

9.3.2Position of differential pressure transmitter

The position of differential pressure transmitter shall be considered for selecting the installation position of SDB averaging pitot-tube flow sensor.

■For liquid and steam,the transmitter is recommended to be installed lower than the root valve.

■For gas,the transmitter is recommended to be installed higher than the root valve.

Please read the transmitter manufacturer's instructions carefully to install the transmitter.

Installation for gas (transmitter above the root valve)

Installation for liquid (transmitter below the root valve)

Installation for steam (transmitterbelow the rootvalve)

10.Impulse Pipe

The requirements for the impulse pipe between SDB averaging pitot-tube flow sensor and differential pressure transmitter are the same as those for differential pressure flow instruments (orifice,nozzle, etc.),which are briefly described here.

10.1 Installation requirements for impulse pipe

The impulse pipe shall be so installed that the differential pressure signal transmitted by it will not causeadditional errorsdueto thedifferential pressure impulse pipeline,and can ensure the safe operation of the throttling device.For this reason,attention shall be paid to the followings during installation of impulse pipes:

(1）The impulse pipe shall be laid at the shortest distance,and its length shall preferably be within 1 6 m generally not more than 5 0 { m } .Its inner diameter shall be greater than 6 {mm } .Generally,the longer the signal pipeline,the larger its innerdiameter.Thisisrelated to the nature of the medium used.The relationship between the inner diameter and length of the impulse pipe is shown in the table below:

(2）The impulse pipe shall be installed vertically or obliquely with an inclination of not less than 1:12, so that the gas (for measuring the liquid medium) or condensate (for measuring the gas medium） can be exhaustedintime.Forviscousfluids,theinclination must be increased.

When the differential pressure signal is transmitted for more than 3 0 { m } ,the impulse pipe shall be inclined in sections,and gas collectors (or exhaust valves）and settlers(blowdown valves）shall be installed at the highest and lowest points respectively.

(3）In order to avoid transmission distortion of differential pressure signal,positive- and negativepressure impulse pipes shall be laid as close as possible,and anti-freezing measures shall be taken for impulse pipes in severe cold areas.

10.2Installation of impulse pipe

The impulse pipe shallbe installed in accordance with the specifications in the standards.

Horizontally installed pipe

Vertically installed pipe

(1）Horizontally installed pipe

a.Liquid as the measured medium:The pipe is
installed horizontally,and the pressure hole can be
installed in parallel or within the range of downward
inclination of 4 5 ^ { \circ } ： b.Gas as the measured medium:The pipe is
installed horizontally,and the pressure hole shall be
installed vertically and upward until it is parallel and
then signal is output. c.Steam as the measured medium:The pipe is
installed horizontally,and the pressure hole can be
installed in parallel or within the range of downward
inclination of 4 5 ^ { \circ } ： (2)Vertically installed pipe a.Liquid as the measured medium:The pipe is
installed vertically.When the fluid flows frombottom

to top,the high-pressure impulse pipe is connected to the differential pressure transmitter after it is led upward and parallel to the low-pressure impulse pipe. When the fluid flows from top to bottom,the lowpressure impulse pipe is connected to the differential pressure transmitter after it is led upward and parallel to the high-pressure impulse pipe.

b.Gas as the measured medium:The pipe is installed vertically. The high- and low-pressure impulse pipes shall be connected to the differential pressure transmitters after they are led upward and parallel.

c.Steam as the measured medium:The pipe is installed vertically.The high- or low-pressure impulse pipes shall be connected to the differential pressure transmitters after they are led upward and parallel.

11.Model SelectionofSDB AveragingPitot-tube Flowmeter

DFFAirVolumeMeasuringDevice

The combustion conditions of a power plant, power station and boiler highly affect the economy and safety of boiler and overall power plant operation. Proper adjustment of combustion conditions,i.e. sufficient fuel combustion,uniform distribution of furnace temperature field and heat load,is necessary condition for ensuring safe,stable and economical operation of boiler.While the accuracy of air volume measurement of boiler directly affects normal operation of boiler operating conditions by operators. With higher automation degree of power plants and power stations,engineers have higher requirements for the stability of air volume measurement.

The existing air volume measuring devices for boilers of power plants and power stations in the market mainly include the flow meters with two principles:1.thermal mass type,2.differential pressure type.Differential pressure type has the most mature and popular application,and the air volume measuring device produced by us is also based on differential pressure principle.However,its revolutionary design makes application principle completely different from the existing differentialpressure flow meters,our air volume measuring device can fundamentally settle the existing bottleneck of the existing measuring devices,and replace the existing air volume measuring devices to become the first choice for air volume measurement of power plants.

MeasurementPrinciples M

DFF air volume measuring device is based on the pitot tube measurement principle: The measuring device is installed ona pipe,with probe inserted into the pipe; in case of air flow in the pipe,the windward side will be impacted by the air flow to convert kinetic energy of the air flow into pressure energy,thus the pipe at windward side has higher pressure which is called "full pressure";the leeward side is free of air flow impact,and its pressure in the pipe is static pressure in the air pipe,which is called "static pressure";the difference between full pressure and static pressure is differential pressurewhich is in direct proportion to the air flow rate(volume) in the pipe; thus the air volume in the pipe can be measured correctly by measuring differential pressure and find out the correspondence of differential pressure and air flow rate (volume).

Due to the large cross section of the air duct of primary and secondary air volume and pulverizing ventilation volume,only one measuring point is insufficient to measure the air volume of the large air duct.In order to measure the accurate primary and secondary air volume and pulverizing ventilation volume of the boiler,we adopt the method of multipoint measurement with uniform cross section on the cross section of the large air duct.We determine the number of measuring points according to the above measurement principle,as well as factors such as the size of each measuring section and the length of straight pipe section; assemble many measuring points with the same cross section,connect one positive pressure side with another and one negative pressure side with another; lead one main pressure pipe from the positive pressure side and negative pressure side respectively and connect them with positive and negative ends of the differential pressure transmitter respectively;obtain average velocity of the section, and calculate the air volume.It has been proved by practice that the device can be put inlong-term reliable service as a maintenance-free product.

▲Schematic Diagram of Single-pointMeasuringDevice

▲Uniform-section Multi-point Diagram of Measuring Device

Q=K\*A\*f(△P,T) ( { m } ^ { 3 } / { h } )

K- total coefficient of arithmetical operation model forairvolumecalculation

A-the area of installation place of air volume measuring device

T- the air temperature corresponding to air flow rate(volume),in { { } ^ { \circ } C }

\triangle \mathbf { P } - output differential pressure of air volume measuring device,in Pa

PerformanceCharacteristics of DFF Air Volume Measuring Device

·DFF air volume measuring device completely settles the problem of signal jamming of air volume measuring devices for dusty air flow;the air volume measuring device has the function of automatic dust removal and anti-blocking by using fluid kinetic energy without any additional compressed air for purging,thus realizing completely long-term maintenance-free operation regardless of dust concentration in the air.

·DFF air volume measuring device has stable performance and good adjustment linearity.

·DFF air volume measuring device has very low requirements for the straight pipe section,and only requiresaposition for installingthrottlingparts,thus the device applies to the installation on complicated pipes.

·Due to the high measurement accuracy,DFF air volume measuring device can ensure long-term measurement accuracy ofwithin ± 1 % ：

Anti-blockingmeasure analysis

Firstly,an automatic dust removal rod is hung in each pressure tapping pipe,which swings irregularly for automatic dust removal under the impact ofair flow in the pipe.The dead weight and thickness of the rod are determined by experiments before leaving the factory according to the range experiment of the design air speed (quantity) in the primary and secondary air pipes or the pulverizing ventilation pipe on the test bench,and underweight rods or rods which are too thick or too thin are disqualified.Secondly,the air volume measuring device has the function of selfcleaning and anti-blocking by using fluid kinetic energy,and it isabsolutely unnecessary to add any compressed gas for purging.Long-term maintenancefree operation can be achieved regardless of the dust concentration in gas.

Feasibilityanalysis

1.Since the installation conditions of straight section of primary and secondary main air pipes of station boiler are not met in many occasions,and because of large air duct section and uneven flow rate distribution on the section,we can lay out the air volume measuring probes at multiple points with the same section,connect positive pressure/negative pressure ends of measuring devices with positive/negative pressure ends respectively,and finally lead a signal group to transmitter,so as to ensure the measurement accuracy,in addition,such combined air volume measuring devices do not have too many requirements for straight section of the air duct.

2.The device completely settles the problem of signal jamming of air volume measuring devices for dusty air flow; the air volume measuring device has the function of automatic dust removal and anti-blocking by using fluid kinetic energy without any additional compressed air for purging,thus realizing completely long-term maintenance-free operation regardless of dust concentration in the air.

3.The air volume measuring device has stable performance and good adjustment linearity.

4.Inserted layout is adopted.For the entire large air duct,screen area of combined air volume measuring device can be ignored,indicating that the pressure loss of the entire air duct fluid is almost zero, the energy conservation effect is significant,and it is

convenient to be installed.

Economic benefit analysis

With the automatic dust removal and antiblocking function,DFF multi-point primary and secondary air volume measuring device ensures longterm measurement accuracy,improves automatic input rateofboiler greatly,and reflects theairvolume inair pipes in time to adjust boiler operation at any time,and keep boiler in operation in economical conditions; to be specific,the device has the functions as below:

1.The device realizes reasonable air distribution of boiler and stable combustion,reduces smoke exhaust temperature,carbon content in fly ash and heat loss of pulverized coal caused by imcomplete mechanical and chemical combustion effectively,and improves the boiler efficiency.

2.The device ensures long-term measurement accuracy,and improvesautomatic input rate of boiler significantly. Boiler operators can make correct judgment according to the change in air volume to facilitate safe and economical operation of boiler.

3.The device can control combustion flame center of boiler effectively to prevent local coking of boiler and prevent flame deviation,and mitigate the deviation of smoke temperature at both sides of furnace outlet.It also prevents pipe burst ofwater wall and superheater.

4.The device can adjust air-coal proportion of coal mill in a reasonable way.The intake air volume of coal mill indirectly reflects coal volume.

5.Inserted layout is adopted.For the entire large air duct,screen area of combined air speed measuring device can be ignored,indicating that the pressure loss of the entire air duct fluid is almost zero,the energy conservation effect is significant,and itis convenient to be installed.

Selection plan

DFF multi-point cross-section measuring device isadopted.Special working conditions such as short straight pipe section and close distance from fan cone on site lead to instable flow field in the pipe,and the possibility of backflow or vortex flow.Measurement accuracy and stability cannot be ensured.In regard of the above complicated working conditions,DFF multipoint cross-section measuring device is adopted,and 16 measuring points are set to ensure accurate detection of pipe flow signal.

Operation result

Many years' operation test shows that DFF multipoint cross-section measuring device has stable performance,good adjustment linearity and stable signal,and realizes long-term maintenance-free operation.

AnnularOrificePlate

1.ProductOverview

1.1 Product introduction

Annular orifice plate isa typical and effective non-standard throttling device.It was introduced in the 1960s and used on site.It has been nearly 1O years since the annular orifice plate wasused in China.An annular orifice plate is constructed so that a circular plate is fixed in the center of the pipe and the fluid flows through the annular channel at the edge of the pipe.In this way,it not only does not destroy the symmetrical structure of the fluid,but also makes the substances with different specific gravity in the pipe pass through their own channels.The substances with larger specific gravity are discharged from the bottom ofthe annular channel,and the substances with lower specific gravity,such as gas and steam,pass through the upper part of the annular channel.The annular orifice plate is not only suitable for the flow measurement of general fluid,but also for the flow measurement of fluid containing various impurities (such as dust,suspension,sediments,etc.).In recent years,it has been successfully applied in the flow measurement of blast furnace gas,coke oven gas, mixed gas,converter gas,water gas,semi-water gas, natural gas,circulating cooling water,industrial wastewater,superheated steam,hot air, flue gas and other media,and has outstanding characteristics in anti-blockage,anti-accumulation,high temperature resistance,deformation resistance and corrosion resistance.

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1.2 Working principle

The annular orifice plate has the same working principle as the standard orifice plate,which is based on the Bernoulli equation and fluid continuity equation.Acircular orifice is installed coaxially in the center of the pipe.When the fluid flows in the pipe and through the annular gap formed by outer edge of the annular orifice plate and inner wall of the pipe,the fluid is accelerated and depressurized due to the sudden contraction of the flow area,thus generating a differential pressure \triangle { P } on both sides of the annular orifice plate.According to the relationship between differential pressure and flow, the fluid flow can be accurately measured.

Basic flowformula:

Where:

qm-mass flow ( { {kg / s } ) } 2
qv-volume flow under working conditions ( { m } ^ { 3 } / { s } ) 0
\triangle \mathfrak { p } - differential pressure (Pa)
pl-working condition density { (kg / m ^ { 3 } ) }
ε-expandability coefficient
C-discharge coefficient
D-pipe inner diameter(m)

1.3 Product features

The special structure of this product determines its many characteristics in application,which are not only well-founded theoretically,but also have been proved by field application.What is more prominent is:

(1）The measurement range is wide.It is not only suitable for the flow measurement of general fluid medium,but also for the measurement of fluid flow containing various impurities (such as dust,suspended solid,sedimentation,etc.),includingvarious gases,hot air,flue gas, natural gas,cooling circulating water, etc.

(2)It has firm structure,stable performance and reliable operation. (3）The equipment is provided with a measuring pipe with a straight section.During installation on site, the installation error (such as eccentricity and sealing washer extending into the pipe) has little impact on the instrument measurement. Therefore,the accuracy of this instrument is higher than that of the standard orifice.

(4)When measuring saturated steam and superheated steam,it can avoid the accumulation of condensate caused by steam failure,and can start accurate metering in a short time when steam is supplied again.

(5) The "grading ring"structure is adopted,and accurate measurement is ensured when the straight pipe section is not long enough.For example: the straight pipe section ahead of the flowmeter downstream of a 9 0 ^ { \circ } elbow is 2D;the straight pipe section ahead of the flowmeter downstream of an elbowis 0 . 5 { D }

(6）The "welding method"is adopted for connection,which is suitable for high-temperature and high-pressure fluids (such as superheated steam),with low cost,reliable operation and stable performance.

1.4 Product structure

The product is divided into the following types according to the connection mode between the annular orifice plate flow sensor and the process pipeline:

(1）Flange connection type (2）Direct welding connection type

Direct welding connection type

2.Maintechnicalparameters

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3.Sensor Connection Size

The dimensions of connection between the annular orifice plate sensor and the process pipe are showninthetablebelow:

4.Sensor Selection

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5.PrecautionsforUse

4.1 Selection of sensor diameter

The nominal diameter of the selected sensor is the same as that of the connected process pipe.This option is convenient for installation.

4.2Selection of diameter code

The diameter code of annular orifice plate flow sensor is expressed in three digits,i.e.the first and second digits of DN and the number of zeros following the first two digits (unit: mm).

Forexample,code 5oo indicates a diameter of 50mm; code 5O1 indicates a diameter of 5 0 0 {mm } 手

4.3Selection of flanges

In addition to the standards of Machinery Department,national standards or standards of the Power Department and Petroleum Department,foreign standards of the United States,Japan and Germany can also be followed to design and manufacture flanges and to meet the needs of various users.

If companion mounting flanges are required, please specify them at the time of ordering.

4.4 Working environment

Requirements of flowmeter for external environment:

There must be sufficient installation space around the flowmeter in order to facilitate installation and maintenance.

\* Refer to Page PO3 for the type spectrum

(1）For a new flowmeter or a throttling device thatis reactivated aftera period of time,check whether the impulse pipeline is blocked or leaked before use.For the liquid medium,fill the impulse pipeline with clean water or other impulse liquid. Pay attention to the exhaust of gas mixed in the pipeline.For the gas medium,pay attention to discharging the accumulated liquid in the pipeline.

(2） Install the settlers or isolators when measuring the flow of fluids containing suspended solids or dust.Pay attention to reasonably selecting the inlet,outlet and drain outlet of the impulse fluid for drainage.It is recommended to select "dirty fluid type" sensor and "differential pressure transmitter with remote diaphragmbox"to measure dirty fluid.