liquid gas steam

Vortex flowmeter

FIS

HE

RM

ET

ER

VT4000

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VT4000

◆ Optimum measuring process reliability enabled by Digital Signal Processing (DSP)

◆ Measurable medium: liquid, gas and steam

◆ High working pressure, 42MPa (max.)

◆

No moving parts and reliable stainless steel structure

◆

Optional double sensors design with higher stability and reliability

◆

VT4000 is fitted with HART communication

◆

±1.0% ◆ Output: 4-20mA analog signal & configurable pulse output

1

Measuring accuracy:

FISHERMETER

Technical parameter

Typical Diameter

Nominal pressure

Fluid temperature

Sensor design

Body material

Accuracy

Repeatability

Flow Range

Converter type

Wafer DN15~DN300, Flange DN15~DN600, Insertion >= DN300

(1.6, 2.0, 2.5, 4.0, 5.0, 6.4) MPa. Other special pressure classes upon request

Standard（-40～+120）℃, M-tem（-40～+250）℃, H-tem（-40～+320）℃

Single sensor double sensors

SS304, 316L, HC and other materials upon request

< 0.33%

1:10～1:20

Communication

Display

T/P compensation

Supply power

Output

Battery power

Linear rectification

Low flow cut-off

HART Protocol

Current：4 -20mA

PulseVoltage

L<1V, H ≥5V

Ex-Design

Protection Class

Applicable medium

Ambient conditions

Ex ia II CT5,Ex d II CT5

IP65

Gas, liquid, steam

Ambient temperature: （-40～+60）℃

Relative humidity: 5%～90% Atmospheric pressure: （86～106）kPa

2

or

±1.0%

Compact & Remote

LCD

In preparation

15~28 V DC

:

Optional

Available

Available

Item VT4000

FISHERMETER

Fig.1

Measuring principle

The vortex flowmeter is used for measuring the flow velocityvof gases and liquids in pipelines flowing full. The measuring

The periodic shedding of eddies occurs first from one side

The vortex shedding frequency f is proportional to flow velocity v and inversely proportional to the width of the shedder d:

f = St × v / d

St, the Strouhal Number, is a dimensionless quantity. If the geometrical shape and dimension of shedder are designed appropriately, St is a constant over the wide range of Reynolds number Re (Figure 3).

Re = v × D / υ υ: Kenematic viscosity of fluid

D: Meter body diameter Strouhal num

ber St

The vortex shedding frequency used to measure the flowrate is only a function of the flow velocity regardless of fluid density and viscosity. The pressure pulsation generating with vortex shedding will be detected by the Piezo-Sensor and converted into pulse signal corresponding to the vortex frequency in the test circuit, and the signal converter will convert this pulse signal into 4-20 mA normalized current signal and output it.

3

FISHERMETER

Fig.2

Fig.3

Principle is based on the development of a Karman vortex shedding street in the wake of a body built in the pipeline.

and then from the other side of a bluff body (vortex-shedding-body) installed perpendicular to the pipe axis. Vortex shedding generates a so-called Karman vortex street withalternating pressure conditions whose frequency isproportional to the flow velocity. (Fig.2)

ρ ρn1,013· p+

1,013-------------------------× 273

273 T+--------------------×=

QV Qnρnρ------ Qn

1,0131,013 p+------------------------- 273 T+

273--------------------×= =

QVQm

ρ----------=

ν ηρ---=

Flowmeter Size SelectionThe flowmeter size is determined from the maximum operating flowrate QVmax. To achieve the maximum flow range, this value should not be less than one half of the maximum flowrate for the meter size (RangeMax), but can be selected as low as 0.15 RangeMax. The start of the linear flow range is a function of the Reynolds Number.

If the flowrate to be measured is specified as normal flowrate, (normal conditions: 0 °C, 1013 mbar) or as mass flowrate, the values must first be converted to actual flowrate values at oper-ating conditions and then the appropriate meter size can be selected from the Flow Range Tables (Tbls. 1, 2, 3).

1. Convert normal density ( ) --> operating density ( )

2. Convert to flowrate at operating conditions (QV)a) starting with normal flowrate (Qn) -->

b) starting with Mass flowrate (Qm) -->

3. Dynamic viscosity ( ) --> kinematic viscosity ( )

= Operating density [kg/m3]

N = Normal density [kg/m3]

p = Operating pressure [bar]

T = Operating temperature [°C]

QV = Operating flowrate [m3/h]

Qn = Normal flowrate [m3/h]

Qm = Mass flowrate [kg/h]

= Dynamic viscosity [Pas]

= Kinematic viscosity [m2/s]ρn ρ

η ν

ρ

ρ

η

ν

QVm

in [m

3 /h]

[10-6m2/s = cSt]ν

0.1

1

10

100

1000

0.1 1 10

DN15

DN50DN40

DN25

DN200

DN150

DN100DN80

DN300

DN250

Fig. 4: Minimum Flowrate, Liquids as a Function of the Kinematic Viscosity

FISHERMETER

4

Flow Ranges, Liquids

Pressure Drop, LiquidsSee Fig. 5 for water (20 °C, 1013 mbar, = 998 kg/m3).For other densities ( ) the pressure drop can be calculated using the following equation:

= Pressure drop fluid [mbar]

= Pressure drop water [mbar] (from Fig. 5)

Static Overpressure, LiquidsTo avoid cavitation when metering liquids a positive static pres-sure (back pressure) is required downstream from the flowmeter. The required pressure can be calculated using the following equation:

p2 ≥ 1.3 x pvapor + 2.6 x

p2 = positive downsteam static pressure [mbar]

pvapor = vapor pressure of fluid at the operating temperature [mbar]

= pressure drop, fluid [mbar]

Example for liquids:Find the flowmeter size for metering 55 m3/h liquid with a density of 850 kg/m3 and a kinematic viscosity of 2 cSt = (2 x 10-6 m2/s).

1. QV = max. 55 m3/h --> DN50[2”] (per Tbl. 1): QVmax = 70 m3/h

2. Flow range start, linear, at 2 cSt, (from Fig. 5): QVmin = 6 m3/h

3. Press. drop (Qv = 55 m3/h) at = 850 kg/m3: = 425 mbar

MeterSize

DN Inch

DIN ANSIQVmin1) RangeMax Frequency QVmin1) RangeMax Frequency[m3/h] [m3/h] [Hz] [m3/h] [m3/h] [Hz]

Std. HT at Qvmax Std. HT at Qvmax 15 1/2“ 0.5 - 6 370 0.5 - 5.5 450 25 1“ 1.6 3.6 18 240 1.6 3.6 18 400 40 1-1/

2“2.4 9.6 48 190 2.5 9.6 48 270

50 2“ 3 14 70 140 3 13 66 176 80 3“ 10 34 170 102 10 32 160 128100 4“ 10 54 270 72 12 43 216 75150 6“ 30 126 630 50 33 106 530 50200 8“ 70 220 1100 45 70 187 935 40250 10“ 70 340 1700 29 82 289 1445 36300 12“ 135 480 2400 26 135 408 2040 23Tbl. 1: Flow Ranges, Liquids at 20 °C, 1013 mbar,

= 998 kg/m3)1) Std. 280 °C Version / HT = High temperature design (fmax = 400 °C

ρ

ρρ

∆p' ρ998---------- ∆p×=

∆p'

∆p

∆p'

∆p'

ρ ∆p'

QV [m3/h]

[mba

r]∆p

Example425 mbar

55 m3/h

DN

15

DN

25

DN

40

DN

50

DN

80

DN

100

DN

150

DN

200

DN

250

DN

300

1

10

100

1000

0.1 1 10 100 1000 10000

Fig. 5: Pressure Drop, Water (20 °C, 1013 mbar, = 998 kg/m3), DIN-Designρ

FISHERMETER

5

Flow Ranges, Gas/Steam

Example for Gases:Find the flowmeter size for metering 2540 m3/h (qn) CO2-Gas; Temp. = 85 °C, Press. = 5 bar a.For details see Page 5 “Flowmeter Size Selection”

= 1.97 kg/m3 (CO2)

1. Convert --> : =7.4 kg/m3

2. Convert m3/h (qn) --> m3/h (qv): QV = 676 m3/h (qv)--> Selection : DN 80[3”] (QVmax = 1200 m3/h) (qv)

3. Pressure drop at = 7.4 kg/m3: = 100 mbar

4. Flow range start at = 7.4 kg/m3 (from Fig. 7): QVmin = 45m3/h, Convert m3/h (qv) --> m3/h (qn): QVmin = 169 m3/h (qn)

Pressure Drop, Gas/SteamSee Fig. 8 for air (at 20 °C, 1013 mbar, = 1.2 kg/m3)For other fluid densities the pressure drop can be calculated using the following equation:

= Pressure drop fluid [mbar]

= Pressure drop air [mbar] (from Fig. 8)

Normal Densities of Various Gases:

MeterSize

DN Inch

DIN ANSIQVmin1) RangeMax Frequency QVmin1) RangeMax Frequency[m3/h] [m3/h] [Hz] [m3/h] [m3/h] [Hz]

Std. HT at Qvmax Std. HT at Qvmax 15 1/2“ 4 - 24 1520 5 - 22 1980 25 1“ 15 30 150 2040 12 16 82 1850 40 1-1/

2“30 78 390 1550 21 68 340 1370

50 2“ 40 100 500 1030 43 90 450 1180 80 3“ 100 240 1200 700 78 190 950 780100 4“ 150 380 1900 500 120 360 1800 635150 6“ 300 900 4500 360 260 810 4050 405200 8“ 430 1600 8000 285 420 1360 6800 240250 10“ 810 2800 14000 260 820 2400 12000 225300 12“ 1410 4000 20000 217 1300 3400 17000 195

Tbl. 2: Flow Ranges, Gases at = 1.2 kg/m3)

1) Std. 280 °C Version / HT = High temperature design (fmax = 400 °C

ρ

ρn

ρn ρ ρ

ρ ∆p'

ρ

Gas Normal Density [kg/m3]Acetylene 1.172Air 1.290Ammonia 0.771Argon 1.780Butane 2.700Carbon dioxide 1.970Carbon monoxide 1.250Ethan 1.350Ethylene 1.260Hydrogen 0.0899Methane 0.717Natural gas 0.828Neon 0.890Nitrogen 1.250Oxygen 1.430Propane 2.020Propylene 1.915

ρ

∆p' ρ1,2-------- ∆p×=

∆p'

∆p

QVm

in [m

3 /h]

[kg/m3]ρ

DN15

DN50DN40

DN25

DN200DN150

DN100DN80

DN300

DN250

1.0

10.0

100.0

1000.0

10000.0

0.10 1.00 10.00 100.00

Fig. 6: Minimum Flowrates, Gas/Steam as a Function of the Fluid Density, DIN-Design (280 °C)

FISHERMETER

6

QV m

in [m

3 /h]

[kg/m3]ρ

DN50DN40

DN25

DN200

DN150

DN100

DN80

DN300DN250

1.0

10.0

100.0

1000.0

10000.0

0.10 1.00 10.00 100.00

Fig. 7: Minimum Flowrates, Gas/Steam as a Function of the Fluid Density, DIN-Design (HT)

[mba

r]∆

p

QV [m3/h]

DN

150

DN

200

DN

250

DN

15

DN

25

DN

50

DN

40

DN

80D

N10

0

DN

300

0.10

1.00

10.00

100.00

1.0 10.0 100.0 1000.0 10000.0 100000.0

Fig. 8: Pressure Drop, Air (20 °C, 1013 mbar, = 1.2 kg/m3), DIN-Design

FISHERMETER

7

Flowrates Saturated Steam [kg/h] Example for Saturated Steam:Find the flow range for DN 50 [2”] at 7 bar (a).--> from Tbl. 3: DN 50[2”]: 101 - 1835 kg/hAdditional information: Sat. steam temp.= 165 °C

Sat. steam dens.= 3.67 kg/m3

Tbl. 3: Saturated Steam Flow Ranges, DIN-Design

p[bar a]1 1.5 2 3 4 5 6 7 8 9 10 12 15 25 30 35 40 45 50 Meter Size

Inch DN1/2“ 15 min

max2

143

215

277

408

529

64976

1088

11100

11112

12124

13147

14182

21300

25360

29420

33480

38544

42609

1“ 25 minmax

989

13129

17170

25248

29324

32401

35476

38551

40624

43699

45773

49920

541140

781875

942250

1092625

1253000

1413401

1583804

1-1/2“ 40 minmax

18230

26335

34441

50644

58842

641041

701236

761431

801622

851817

892009

992391

1222964

2014875

2415850

2826825

3227800

3658841

4089890

2“ 50 minmax

24295

34430

45565

66825

771080

861335

941585

1011835

1072080

1142330

1192575

1303065

1453800

2086250

2497500

2918750

33310000

37711335

42212680

3“ 80 minmax

59708

861032

1131356

1651980

1932592

2153204

2343804

2524404

2684992

2845592

2986180

3297356

4089120

67115000

80518000

93921000

107324000

121727204

136130432

4“ 100 minmax

891121

1291634

1702147

2483135

2904104

3225073

3616023

4186973

4747904

5318854

5869785

69811647

86514440

142323750

170828500

199233250

227738000

258143073

288748184

6“ 150 minmax

1772655

2583870

3395085

4957425

5809720

64412015

72214265

83616515

94718720

106120970

117323175

139627585

173034200

284656250

341567500

398478750

455490000

5162102015

5774114120

8“ 200 minmax

2544720

3706880

4869040

71013200

86317280

106721360

126725360

146729360

166333280

186337280

205841200

245049040

303860800

4996100000

5995120000

6995140000

7994160000

9061181360

10136202880

10“ 250 minmax

4788260

69712040

91515820

133723100

156530240

174037380

194944380

225651380

255758240

286565240

316672100

376885820

4672106400

7684175000

9221210000

10758245000

12295280000

13936317380

15590355040

12“ 300 minmax

83211800

121317200

159322600

232733000

272443200

309253400

330063400

355173400

378083200

400193200

4269103000

5081122600

6300152000

10361250000

12434300000

14506350000

16578400000

18791453400

21021507200

Density sat[kg/m3] 0.59 0.86 1.13 1.65 2.16 2.67 3.17 3.67 4.16 4.66 5.15 6.13 7.60 12.50 15.00 17.50 20.00 22.67 25.36

Temp. Tsat [°C] 99.6 111.4 120 133 144 152 159 165 170 175 180 188 198 224 234 242 250 258 264

ρ

FISHERMETER

8

Exia II CT5

VT

Converter type 4 Type of connection

Wafer

（DN15～DN300)

0

Flange （DN15～DN600) 1

Insertion （≥DN350）

2

Type of converter

Compact 0

Remote 1

Measuring medium Liquid 0 Gas 1 Steam 2

Materials

C

M

Meter

Size

DN15

15

DN20

20

DN25

25

DN40

40

DN50

50

DN80

80

DN100

1H

DN125

1T

DN150

1F

DN200

2H

DN250

2F

DN300

3H

...

...

8H

Probe type

Standard

(-40～+120)℃

0

High

temperature (-40～+250)℃

1

Super

temperature (-40～+320)℃

2

Sealing

Graphite

0

PTFE

1

Others

9

Explosion proof

None

A

B

C

None

0

1

9

DN800

Pressure RatingPN16PN20PN25PN40

BLC

D

Others

Ex ia II CT5Ex d II CT5

LC

600LB

PN63

150LB

EFPN100

300LBNP

K

316LSS304

HCOthers

AB

HART

Order series

G

FISHERMETER

Ordering Selection of Vortex Flowmeter

Yes

Profile and installing dimension

Flange connection (mm)

DN

15

20

25

40

50

80

100

125

150

200

250

300

PN 40

40

40

40

40

40

16/40

16/40

16/40

16/25

16/25

16/25

L 200

200

200

200

200

200

250

250

300

350

450

500

H 300

300

300

340

350

365

375

390

400

425

450

475

d 15

20

25

40

50

80

100

125

150

200

250

300

D 95

105

115

150

165

200

220/235

250/270

285/300

340/360

405/425

460/485

k 65

75

85

110

125

160

180/190

210/220

240/250

295/310

355/370

410/430

d1 14

14

14

18

18

18

18/22

18/26

22/26

22/26

26/30

26/30

N 4

4

4

4

4

8

8

8

8

12

12

12/16

b 14

16

16

18

20

24

22/24

22/26

24/28

24/30

26/32

28/34

DN PN 15 25

20 25

25 25

40 25

50 25

80 25

100 25

125 25

150 25

200 25

250 25

300 25

L 65

65

65

65

65

65

65

65

65

100

100

120

H 310

310

310

315

320

320

330

345

360

400

425

460

D 55

55

55

85

100

130

150

175

200

250

300

350

d

Wafer connection (mm)

15

20

25

40

50

80

100

125

150

200

250

300

10

FISHERMETER

Installation The installation site and fixing manner of flowmeter will have a direct impact on its application. Incorrect installation will influence the measuring accuracy and the service life of the flowmeter, and even cause permanent damage to it,so the following items shall be referred during the installation.

Inlet and outlet sections The installation of flowmeter shall satisfy the minimum requirements for the inlet and outlet straight section as shown Figure 9, or it will have a serious impact on the measuring accuracy or even on normal function of flowmeter.

Figure 9 Length of inlet and outlet straight section (D: The nominal internal diameter of the meter)

Installation for high fluid temperatures When the temperature of medium in the horizontal pipe is above 180 , it is recommended that the ℃ remote type of flowmeter or side mounting be chosen, that is to say, the head of flowmeter is not on the top of the pipe, because high temperature may damage the electronic circuit in signal converter. Correct installation manner is as shown in Fig.10

Fig.10: Installation for high fluid temperatures Fig.11: Low installation shall be avoided for steam measurement (Temperature ≥180 )℃ .

Installation for steam measurement

When the measured medium is saturated steam or humid gas, the flowmeter shall not be installed at the lowest part of pipe line (Fig.11), because the steam may condense into liquid at the lower part of pipe line, causing coexisting of water and steam, whichmay result in failure in performance of flowmeter and greater measuring errors. In addition, when the steam device is being opened, water hammer may appear at the lower part of pipe line.

11

FISHERMETER

Installation for liquid measurement

Fig.12: High installation shall be avoided for liquid measurement

Fig.13: Up-to-down flow shall be avoided for installation of vertical pipe line

Thickness of thermal insulation layer

Fig.14: Thickness of thermal insulation layer

Fig.15:

Required distance for

flowmeter maintenance

Service clearance

Installation of Remote type flowmter

12

FISHERMETER

When the measured medium is liquid, the liquid shall be full of the pipe, and it is better to make the liquid flow from a lower position to a higher or flow horizontally.

The flowmeter shall not be installed at the highest part of pipe line (Fig.12), because the air bubbles may gather there and cause a serious impact on the measuring accuracy.If the pipe is vertical, the liquid shall not flow from up to down (Fig.13), or the pipe will not be full, which may seriously influence the measuring accuracy and cause failure in performance of flowmeter.

If the pipe line needs to be kept warm, the thickness of thermal insulation layer covering the instrument shall not exceed 50 mm (Figure 14). The excessive thickness may cause a rise in temperature of signal converter which leads to a damage.

More than 200 mm clear space for mounting, dismounting and maintenance shall be allowed at the top of flowmeter during installation (Figure 15).

The installation of separate flowmeter body is identical to that of compact flowmeter. The signal converter must be firmly fixed on the wall or in the cabinet. The longest transmission distance between the signal converter and primary body is 10 meters, and the connecting cable is two-core shielded cable. The shorter the signal transmission distance is, the less the interference. So it is needed to shorten the cable length according to actual need and cut the excessive cable. The unamplified signals from the transducer to signal converter may be easily interfered during transmission, so care must be taken to connect wires and the shielding layer shall be grounded reliably at the same place where the power is grounded. After grounding, the cable shall be fixed and better in the special cable trunk (Figure 16).

Precaution

◆ Try to avoid vibration, and rubber the support or connect by the hose if necessary. ◆ If the pressure fluctuation occurs when there is no flow in a long pipe, a gate valve is needed to be installed before and after

the flowmeter.

◆ If water is contained in the steam or steam in water, a water separator shall be equipped.

◆ Installations for wafer type, flange connection and insertion type are separately as shown in Figure 17, 18 and 19.

Fig.17: Wafer type Fig.16: Remote type

13

Fig.19: Insertion type Fig.18: Flange connection

FISHERMETER

Contact us

Once a quotation inquiry is received, a regional sales representative will contact

you within 24 to 48 hours.

International Sales Department

Tel: +86-10-8483 3261

+86-10-8483 3671

Fax: +86-10-8482 9367

+86-10-8483 3673

E-mail：sales@fishermeter.com

Technical Service

Tel; +86-10-8947 8461-605 / 606

+86-10-8947 8421-605 / 606

Fax: +86-10-8947 8461-607

+86-10-8947 8421-607

E-mail：service@fishermeter.com

Office Address

Beijing Fishermeter Instrument Co., Ltd.

Post Code: 100107

Room 1204, B Block Fortune Center, Tianlang Garden,

Beiyuan Road, Chaoyang District, Beijing, China. (100107)

http://www.fishermeter.com/english

Factory Address

1st building, Mauhwa Industry Park 1st block, Caida 3rd street, Caiyuan Industry Park,

Nancaizhen Town, Shunyi District, Beijing, China.

14

FISHERMETER