PProducts

 

Overview

      LUDC Series  Vortex Shedding Flow meter is used in the
flow measurement of the fluid in the industrial pipe line, such
as  gas ,  liquid ,  steam ,  etc . . lts  characteristics  are  less
pressure  loss,  no  movable  mechanism  in  the meter. This
flow  meter  adopts  piezoelectric  sensor,  has high reliability,
works with in -20℃ to + 250℃. There are standard analogue
signal (4-2OmA) or pulse signal outputs, it is easy to be used
together with digital systems, such as computer, etc.

Measure Principle

    If insert a columnar object vertically in flow, it will generate vortex turn and turn about at both side,

move to lower reaches of thevortex turn and turn about at both side ,move to lower reaches of the flow,

and form a series of vortexes, it was called as CARLMANvortex, see figura1. The object that generate

vortex is called as vortex generate. This experiment certifies that frequency of vortex is indirect proportion

to flow speed it can be shown as follow formulae:

  

The experiment certifies: the non-symmetrical vortex series can keep steady condition if the dimension

between two line "h" and thedimension between two vertex" L" at same line are satisfied with the formula

L/H=0.281. If the "Re" of flow is changed from 5000 to150000, the "Sr" almost won't be changed. So when

the width of the vortex generated "d" and the "Sr" are definite value, thefrequency of vortex generated "f"

is in direct proportion to average flow speed, this is to say that is in direct proportion to outflow, buthave

no link to pressure, temperature, density etc. parameters.

When vortexes are generated at both side of the columnar object, transducer affected by alternate 

ascending force at the direction ofvertical with flow, and induced signal. The alternating frequency of the

ascending force is vortex frequency. After the transducertransmits the signal go converter and amplify

and shape is, it gains impulse signal in line proportion to flow speed, and then turn itdirectly or concert it

into 4~20mAstandard signal output. The relationship between outflow " Q" and frequency "f" ad follow

formulae:

 

 

 

Technique parameter             

                                                                                                                                             Table   1                                                                                                                                                

Medium

LUDC

Medium

Air, liquid, steam

Diameter

Wafer type

15, (20), 25, 32, 40, 50, 65, 80, 100, 125, 150

Flange connection type

200

Flow rate

Normal flow velocity range

Gas 5-50m/s Liquid 0.5-7m/s

Normal flow rate range

Liquid, gas, steam type flow range refer to table 2,3 as follows

Accuracy

Liquid ±1% ,  or gas (steam) ±1.5%

Medium temperature

Normal temperature   -25℃~80℃,  Heat temperature -25℃~250℃

Working pressure

1.6MPa; 2.5MPa；4.0MPa(Supply as order's requirement)

Output signal
(signal cable
connection is
M20x1.5)

 

Pulse voltage
Output signal

 

 

High level 8-10V  Low level 0.7-1.3V 
(Ex-proof version: High level 4-5V  Low level 0.7-1.3V)

 

Duty ratio of pulse is about 50%, transmission distance 100 meters.

 

Standard
current output signal

 

Allowable external load resistance less the 600 Ω(24VDC)                           Transmission distance is 3000 meters

Working environmental condition

temperature   :  -25℃~+55℃     humidity  :  5-90%  RH50℃

Material

Meter body :  1Cr18Ni9Ti  Converter  housing :  AL-allog

Power supply

24V  DC±10% ;   Or dual lithium battery 3.6 V 7.5 Ah

Protection grade

IP65
Requirement of straight connecting
pipe on both sides of the meter

Upstream ≥15-35 DN ; Downstream ≥ 10 DN

 

Liquid and air flow-range                                                                                                    Table  2                    

caliber
mm

 DN mm

15

20

25

32

40

50

65

80

100

125

150

200

250

300

liquid

 m3/h

0.3~3

0.5~5

1.2~12

1.5~15

2.2~22

4~40

6~60

9~90

14~140

22~220

35~350

65~650

120~1200

180~1800

air

 m3/h

5~30

5.5~56

10.2~80

15~150

22~220

35~350

60~600

90~900

140~1400

220~2200

300~3000

550~5500

1100~11000

1500~15000

 

 

 

Saturation steam flow-range

                                                                                                                                                     Table   3           

Path  25mm 32mm 40mm 50mm 65mm 80mm 100mm 125mm 150mm 200mm

temperature
℃

Density

kg/m3
  Minimum Maximum Minimum Maximum Minimum Maximum Minimum Maximum Minimum Maximum Minimum Maximum Minimum Maximum Minimum Maximum Minimum Maximum Minimum Maximum
0.1 20 101 22.5 150 36 229 59 358 93 600 129 917 220 1.43 348 2.25 479 3.22 840 5.73 120.1 1.126
0.2 21 136 29.5 210 47 333 77 520 124 880 168 1.33 288 2.08 463 3.30 628 4.68 1.10 8.34 133.3 1.638
0.3 24 151 36 280 56 436 92 680 152 1.15 201 1.74 345 2.78 567 4.30 750 6.13 1.32 11.0 143.2 2.140
0.4 27 186 42 340 65 536 105 836 171 1.40 231 2.14 396 3.39 640 5.24 862 7.54 1.51 13.6 151.4 2.635
0.5 30 248 46 410 72 636 118 994 188 1.69 259 2.55 444 3.98 691 6.23 966 8.95 1.70 15.9 158.3 3.127
0.6 34 256 50 470 80 733 130 1.15 206 1.95 285 2.94 489 4.66 766 7.20 1.07 10.3 1.87 18.6 164.4 3.615
0.7 37 325 54 530 87 833 142 1.30 225 2.20 310 3.34 531 5.22 832 8.15 1.16 11.7 2.03 20.9 169.8 4.099
0.8 39 325 58 600 93 931 152 1.45 243 2.47 334 3.73 572 5.91 888 9.10 1.25 13.1 2.19 23.6 174.7 4.581
0.9 42 394 62 650 100 1.03 163 1.61 253 2.73 357 4.12 612 6.44 936 10.0 1.34 14.5 2.34 25.8 179.2 5.064
1.0 45 441 66 720 106 1.13 173 1.76 272 3.00 379 4.51 650 7.16 1.00 11.0 1.42 15.8 2.49 28.6 183.3 5.553
1.1 47 479 70 780 112 1.23 183 1.92 289 3.26 401 4.91 687 7.67 1.07 12.0 1.50 17.3 2.63 30.7 187.2 6.033
1.2 50 463 73 850 118 1.32 193 2.05 306 3.50 422 5.29 723 8.40 1.12 13.0 1.58 18.5 2.76 33.6 190.8 6.509
1.3 52 555 77 910 123 1.42 202 2.22 314 3.77 422 5.68 757 8.88 1.17 13.9 1.65 20.0 2.89 35.5 194.2 6.980
1.4 54 593 79 970 129 1.51 211 2.37 328 4.00 461 6.07 792 9.49 1.22 14.8 1.73 21.3 3.02 37.6 197.5 7.456
1.5 57 630 82 1.00 135 1.60 219 2.52 341 4.30 481 6.47 825 10.3 1.26 15.8 1.80 22.6 3.15 41.4 200.5 7.934
1.6 59 669 86 1.10 140 1.71 229 2.68 353 4.55 501 6.86 858 10.7 1.31 16.8 1.87 24.1 3.28 42.9 203.5 8.419
1.7 61 707 89 1.15 146 1.81 237 2.83 365 4.80 519 7.24 890 11.3 1.36 17.7 1.94 25.9 3.40 45.3 206.2 8.897
1.8 63 746 93 1.22 151 1.91 246 2.98 385 5.07 538 7.64 922 11.9 1.41 18.7 2.01 26.9 3.53 47.8 208.9 9.388
1.9 66 784 96 1.28 155 2.01 254 3.14 395 5.33 556 8.03 954 12.6 1.46 19.6 2.08 28.3 3.65 50.0 211.5 9.868
2.0 68 822 98 1.35 161 2.10 262 3.27 404 5.60 574 8.43 985 13.2 1.50 20.6 2.15 29.6 3.76 53.5 213.9 10.35
3.0 87 1.21 128 1.98 207 3.10 338 4.84 532 8.21 743 12.4 1.27 19.3 1.95 30.3 2.78 43.5 4.86 77.4 234.6 15.21
4.0 106 1.61 158 2.60 251 4.11 409 6.43 647 11.0 898 16.5 1.53 25.7 2.40 40.2 2.35 57.8 5.87 102.8 250.7 20.21
4.3 111 1.73 161 2.80 264 4.43 429 6.91 666 11.6 942 17.7 1.61 27.7 2.47 43.0 3.52 62.2 6.17 110.6 254.9 21.74

Note: Unit in red frame data is t/h Rest is kg/h. Unit of pressure: Mpa

 

Liquid and air flow-range of insert type                                                                         Table   4       

caliber mm
DN

Liquid(m3/h)

Air(m3/h)

caliber mm
DN

Liquid(m3/h)

Air(m3/h)

Minimum

Maximum

Minimum

Maximum

Minimum

Maximum

Minimum

Maximum

200

55

570

560

4530

900

1145

11450

11450

91605

250

88

885

880

7070

1000

1410

14140

14135

113095

300

125

1275

1270

10180

1100

1710

17110

17100

136840

350

170

1735

1730

13860

1200

2035

20360

20230

162850

400

225

2265

2260

18100

1300

2385

23895

23890

191125

450

286

2870

2860

22905

1400

2770

27710

27705

221660

500

350

3540

3530

28275

1500

3170

31800

31700

254455

600

505

5090

5085

40715

1600

3610

36200

36105

289510

700

690

6930

6925

55420

1800

4580

45850

45750

366410

800

900

9050

9045

72380

2000

5650

56550

56545

452365

 

 

 

Construction and size

This serise have three kinds of connection ways and
external dimension
 
◎    Wafer connection type
        Use  for  Vortex  Shedding  flow-meter  in   DN15~150  See  Fig.3  and  table  5
◎    Flange connection type
      Use  for  Vortex  Shedding  flow-meter  in  DN125~300  See  Fig.3  and  table  5
◎     Insert type
      Use for big caliber piping in DN200~2000 See fig 4
      (The ball valve is used in flowing constantly and loaded and unload mainly, benefit
      washing regularly and maintenance while running in the dirty corrupt medium. ready
      as users' requirement)      

 

                                     

 

Dimensions

Form
Nominal
Caliber

 

Pressure
Grade

L

mm

G

D

mm

d1

mm

N-d2

d

mm

b

mm

 

 Weight 
Kg

 

Normal
  temperature 

 

Heat
  temperature 

Wafer

 

Type

15(20)

 4.0

66

280

500

65

－

－

15

－

7.5

25

 4.0

66

280

500

65

－

－

25

－

7

32

 4.0

66

285

505

72

－

－

32

－

10

40

 4.0

70

290

510

80

－

－

40

－

11

50

 4.0

85

295

515

90

－

－

50

－

12.5

65

2.5

98

310

530

105

－

－

65

－

17

80

2.5

110

320

540

120

－

－

80

－

20

100

2.5

110

330

550

150

－

－

100

－

27

125

1.6

115

340

560

164

－

－

125

－

30

150

1.6

130

350

570

188

－

－

150

－

35

Flange

type

125

1.6

250

323

545

245

210

8－φ18

125

26

22

150

1.6

300

335

555

280

240

8－φ23

150

28

24

200

1.6

320

370

590

335

295

12－φ23

200

30

31

250

1.6

320

400

620

405

355

12－φ25

250

32

40

300

1.6

320

420

640

460

410

12－φ25

300

32

48    

 

Modeling Code

Mode Basic code Note
LUDC     Basic model of stress vortex transmitters
connection -1     Flange connection type
-2     Wafer connection type
      medium 2     Liquid
3     Gas
4 or 4G     Saturated steam (4G at overheating steam)      
5     hot water
            Cutput signal - x x x     See bottom table ( mm )
                        Output signal - 0     No signal output
- 3     There wire pulse
- 4     Two wire 4-20 mA
                                            lndicator of
                                           instrument
 N     No indicator
B     Dual row LCD,(instantaneous and tolaieing flowrates)   
                                                                  Power
                                                                  supply
 x     12V   DC (Only used in three wire system pulsed output) 
y     24V   DC
z     Power supplied by battery ( Only used inB indicator )
                                                                       material of  
                                                                        instrument   
 - C     OCr18Ni12Mo2Ti  (316)
- D     1Cr18Ni9Ti  (304)
                                                                                        Pressure 1     1.6MPa   (DN65-200)
2     2.5MPa   (DN15-50)
3     4.0MPa   (DN15-50)
                                                                                      performance of
                                                                                      explosion-protechion
     - N   No
    - Bi   Intrinsically safe class
    - Bd   Explosion proof

 

Nominal Caliber                                                                                              Table 6

caliber mm

15

20

25

32

40

50

65

80

100

125

150

200

250

300

350

400

450

500

Marking

001

0012

002

003

004

005

006

008

010

012

015

020

025

030

035

040

045

050

 

caliber mm

600

700

800

900

1000

1100

1200

1300

1400

1500

1600

…

2000

Marking

060

070

080

090

100

110

120

130

140

150

160

…

200

 

 

 

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