Integral type
Differential pressure flowmeter

VDT Series
OUTLINE
VH series Wafer-Cone® differential pressure flowmeter and DT series
multi digital differential indicator are integrated into one flowmeter. As
the meter requires little straight runs and little head loss compared toorifice plate, it offers you reduction of construction cost and energysaving.

FEATURES❑ Simple installation
Wafer connection makes installation simple. Flowmeter bodyflanges designed to match the pipe flanges guides to the pipe center line.
❑ Short straight runs
The required straight runs are less than 1/5 of those required for
orifice and vortex flowmeters. The narrow installation space allows
simple and flexible piping arrangement plan. It leads to space andcost saving.
❑ Low pressure loss
A proper selection of β ratio allows lower pressure loss than orificeplate with the same flow rate. It improves energy efficiency of theplant.
❑ Wide rangeability❑ Matching any flow direction

Since the differential pressure created by the meter is stable at low

It can measure either horizontal, vertical, upward, or downward flow.

flow rate, it can measure the flow rate in the range of the turn down

The orientation of the indicator can be set in a simple way at field.

ratio 14:1 to cover the wide flow range with one flowmeter.
❑ Various functions of indicator❑ Wear and adhesion resistantBattery type or current output type can be chosen. Indicator part is

V shape cone has durable structure against wear or adhesion. It caninterchangeable. The differential pressure range can be changed bymeasures challenging slurry or flue-gas process lines that ordinarychanging indicator.

orifice could not deal with.
❑ Easy-to-read big LED display❑ No impulse piping work required

The instantaneous flow rate is indicated with the 18mm high char-

Direct mounting of digital differential transmitter/indicator requires

acters on the LCD display. Optionally, the integrated flow quantity

no impulse piping to save installation cost.

is also indicated with the 5mm high characters at the same time.

TG-F1022-E02
3rd edition Mar 2020 K
2nd edition Jun 2008 K

VDT series Integral type Wafer-Cone® Differential pressure flowmeter

MEASUREMENT PRINCIPLE

STANDARD SPECIFICAION

The principle of V-Cone flowmeter is the same as that of a common● Meter size

25, 40, 50, 65, 80, 100 mm

theorem of the conservation of a fluid energy.

● Connection

Wafer type

As shown in Fig.1, the pressure P1 at the approaching point to V-● Rating

JIS10K,20K

differential pressure type flowmeter, and it is based on the Bernoulli’s

1, 1-1/2, 2, 2-1/2, 3, 4 inch

Cone decreases to P2 at the edge point with increasing fluid velocity

ANSI Class150, 300

by throttling the flow path along the contoured shape of V-Cone.

DIN PN16, 40

P1 and P2 are measured from the pressure taps and the difference ofthe two pressures is given as:

ΔP=P1-P2

GB PN1.6, 4.0● Connection size

Same as meter size

● Materials

See Dimensions and Materials as● Measuring fluid

Liquids and Gases (Steam can not● Fluid pressure

Maximum 0.5MPa

described later.

ΔP is differential pressure output.
Energy loss

P1

Velocity energy

Total energyof a fluid
Pressure energy

be measured)● Fluid temperature

Maximum 70°C

● Ambient temperature–20°C to 60°C

● Humidity

35% to 85% RH (No condensate,● Measuring range*

Liquids : 0 to 10 m/s

No freezing)

P2

Gases : 0 to 80 m/s
ΔP* Where low cut is set as 0%. As standard the low cut is set as 7%.
● Guaranteed accuracy range

Max. Rangeability 14:1
Depends on differential pressure
range.

● Accuracy of the reading
P2

P1±1.5 to 2.5% of Full Scale
Depends on differential pressure

FLOWrange.
CONE● Flow direction

Either horizontal, vertical, upward,
or downward flow

INDICATOR SPECIFICATION
Refer to the DT series TECHNICAL GUIDANCE TG-EM125E for the[Fig. 1]

2

TOKYO KEISO CO., LTD.

details of digital indicator.

TG-F1022-E02

VDT series Integral type Wafer-Cone® Differential pressure flowmeter● Required straight runs

● Specification and function of indicator type

[Measuring fluid : Liquids general and Gases with Reynolds
No. < 200,000]
Type of joints

Upstream side

Downstream side

1 piece of 90° bend

0D

0D

2 pieces of 90° bend

0D

0D

T joint

0D

0D

Butterfly valve(Flow control valve)

3D

3D

Butterfly valve (Fully open)
Gate valve (Fully open)

3D

0D

0D

0D

Expander(Diameter 0.67D expands
to 1D, length 2.5D)

1D

1DReducer(Diameter 3D reduces
to 1D, length 3.5D)

1D1D1) Battery type
Battery: AA alkali dry battery (LR6) × 2 pieces

Battery life

: Approximately 2 year’s continuous service at23°C
Auto power off mode selectable
Low battery monitor attached as standard2) Current output type
Power supply: 24V DC±10%Output signal: 4-20mA DC (2 wire system)

Maximum load

: 600 ΩOutput accuracy: ±0.5% F.S. at 23°CResponse: Less than 2 seconds with filter set as 0Wiring connection: Water-proof cable gland
Applicable cable outer diameter 3 mm ∅to 8 mm ∅Connection diagram :OUT 2[Measuring fluid : Gases with Reynolds No. >200,000]

OUT 1Downstream side—

1 piece of 90° bend

1D

1D+/ANA OUT

2 pieces of 90° bend

1D

1D

T joint

1D

1D

Butterfly valve(Flow control valve)

10D

5D

ACCESSARIES

Butterfly valve (Fully open)

5D

3D● Indicator protection coverGate valve (Fully open)

1D

1D

Expander(Diameter 0.67D expands
to 1D, length 2.5D)

2D

2D

Reducer(Diameter 3D reduces
to 1D, length 3.5D)

1D

1D

4-20mA ++– –Receiving
instruments

Upstream side

Type of joints

DC24V

Provide the indicator protection cover to avoid direct sunshine andwater splash if required.
The protection cover might make the reading difficult.

OPTION (provided at the factory)● Totalizer indication
If the totalized flow quantity indication is required, add the Code TLZ.

[Notes]· D shows the nominal size of Wafer-Cone flowmeter.
· The required straight runs are the distance from the flange facesof Wafer-Cone flowmeter.
· Add 1D to the above mentioned figures for the service β ratio is0.65 or more.
● Indicator type and its function All indicator types have local indicators.

TypeFunction

Battery type

Battery driven, Local indication only

Current output type

4 to 20 mA two wire system● Indicator function
Flow rate indication: 3-1/2 digits LCD (Character height 18mm)
Indicated as “0 to 1999”.
11 segment bar graph indication

Totalizer indication: 7-1/2 digits LCD (Character height 5mm)

Indication cycle: 1 sec.(Sampling ;0.5sec.)

Filter: Selectable from 0, 2, 4, 8, 16, 32s

LCD Back light: Light on during 10 seconds at key operation

Indicated as “0 to 19999999”(Moving average method)
excluding current output type.

TG-F1022-E02

TOKYO KEISO CO., LTD.

3

VDT series Integral type Wafer-Cone® Differential pressure flowmeter

SIZING
Based on a selected Wafer-Cone β ratio, the differential pressure atmaximum flow range is determined by the meter size and fluid properties. The maximum differential pressure corresponds to the maximum
flow range of indicator. The maximum differential pressure can beselected as required by designating a Wafer-Cone β ratio and a flow
range if meter size and fluid properties are given.
The Wafer-Cone® sizing program presents a solution to meet yourrequirements such as low pressure loss measurement or more precise
flow measurement.
Please contact TOKYO KEISO for further information of the WaferCone® sizing program.

MAXIMUM FLOW RANGE● Maximum flow range when measuring 20°C water· The accuracy is guaranteed up to the maximum flow rate in the list atMeter size/connection size25A1"

the accuracy is guaranteed is 1/14 or 1/10 of the maximum flow rate.
DN2540A

1-1/2"

DN4050A

2"

DN5065A

2-1/2"

the written size and fluid pressure. The minimum flow rate at which

Maximum flow rate [m3/h]

DN65

80A

3"

DN80

100A

4"

DN100

Min.

(5.51)The maximum flow rate in parenthesis in the list guarantees the ac-Max.

(7.50)

curacy within 1:10 of the maximum flow rate.

Min.

(8.62)

Max.

19.03

· You can find following calculation results by using the Wafer-Cone®

Min.

(11.24)sizing program: Fluids other than ones in the list, Flow range at op-Max.

31.10

erating conditions, Maximum differential pressure, Permanent pres-Min.

(13.42)sure loss

Max.

42.64

Min.

(16.71)

Max.

68.79

Min.

(22.15)

Max.

119.73· When pressure and temperature compensation is required for gas
measurement, calculate maximum flow rate using the Wafer-Cone®
sizing program.

● Maximum flow range when measuring 0°C air with gage pressure
Maximum flow rate [m3/h(nor)]

Meter size/connection size
25A

41"

DN2540A

1-1/2"

DN4050A

2"

DN50

65A

2-1/2"

DN6580A3"

DN80

100A

4"

DN100

Fluid
pressure
[MPa]

0.0

0.1

0.2

0.3

0.4

0.5

Min.

(77)

108

108

108

108

108

Max.

(99)

198

296

381

430

475

Min.

(120)

168

168

168

181

169

Max.

252

502

753

969

1094

1206

Min.

(155)

217

217

217

230

252

Max.

412

821

1231

1585

1788

1971

Min.

(186)

261

260

301

337

369

Max.

565

1126

1688

2173

2452

2703

Min.

(232)

328

403

466

522

572

Max.

912

1818

2724

3505

3956

4361

Min.

(308)

570

701

811

908

996

Max.

1587

3164

4742

6102

6886

7591

TOKYO KEISO CO., LTD.

TG-F1022-E02

VDT series Integral type Wafer-Cone® Differential pressure flowmeter

MODEL CODESMODEL CODESVDT□Materials of detector1□□□–□□ –□□□□CONTENTS/□□□SCS14A/SUS316
325A

1"

DN25

440A

1-1/2"

DN40

Meter size

550A

2"

DN50/Connection size

665A

2-1/2"

DN65

780A

3"

DN80

8100A

4"

DN100

Connection rating

J1

JIS10K

J2

JIS20K

A2

ANSI Class 150

A5ANSI Class 300

G1

GB PN1.6

G4

GB PN4.0

D1DIN PN16

D4DIN PN40

V-Cone β ratio–450.45–500.50–550.55–60

0.60

–65

0.65

–70

0.70

–75

0.75–80

Differential pressure range of indicator

0.80– 022kPa

– 05

5kPa

– 1010kPa– 2020kPa
4Indicator type

Battery type

5Current output typeL

Measuring fluids

Liquids

GGases

Option/TLZ

Totalizer indication

STUD BOLT SIZE
Following size of stud bolts for the mounting are recommended.

JISConnection rating
Meter size

ANSI

10K(mm)20K(mm)Class150(inch)

DIN

GB

Class300(inch)

PN16(mm)

PN40(mm)

PN1.6(mm)PN4.0(mm)

25A

1"

DN25

M16×130M16×140

1/2×5

5/8×5-1/4

M12×130

M12×130

M12×130

M12×13040A

1-1/2"

DN40

M16×160

M16×160

1/2×6

3/4×6-3/4

M16×160

M16×160

M16×160

M16×160

50A

2"

DN50

M16×170

M16×170

1/2×6-1/2

5/8×6-3/4

M16×170

M16×170

M16×170

M16×170

65A

2-1/2"

DN65

M16×190

M16×190

5/8×7-1/2

3/4×8

M16×190

M16×190

M16×190

M16×190

80A

3"

DN80

M16×210

M20×220

5/8×8-1/4

3/4×9

M16×210

M16×220

M16×210

M16×220

100A

4"

DN100

M16×240

M20×260

5/8×9-1/2 3/4×10-1/2 M16×240

M20×260

M16×240

M20×260

TG-F1022-E02

TOKYO KEISO CO., LTD.

5VDT series Integral type Wafer-Cone® Differential pressure flowmeter

DIMENSIONS● For gases⑪⑩⑨⑧①OUT1OUT2100⑤⑥⑦⑫UNIT②③④m3/h
cm3/h

500

LRZ

SETADJ.
Aoff

k Pa

CMODE

FLOW

L(A)

● For liquids

OUT1FLOW

OUT2100

UNIT
m3/h
cm3/h

500

LRZ

SETADJ.
Aoff

k Pa

C

MODEL(A)● Materials
Part No.

● Dimension list

123Body

SCS14A

Metersize(mm)Cone

SUS31625572192.7

SUS3164076

2283.75086234

4.2

65

102

249

6.2

80

121

264

8.2

100

152282

12.7

Part name

Detector

4Materials

SupportFastening bolts

SUS316L

Body

SCS14

Cock axis

SUS316

7O-ring

Fluorocarbon rubber

8Diaphragm

SUS316L

9

Body

SUS316O-ringFluorocarbon rubber

Drain hole

Alumina

SealCeramics

56101112

Cock piece

Indication
part

Indicator housing

L(mm)

A(mm)

Weight(kg)ADC12Wafer-Cone® is registered trademarks of McCROMETER, Inc.

* Specification is subject to change without notice.

Head Office : Shiba Toho Building, 1 – 7 – 24 Shibakoen, Minato-ku, Tokyo 105 – 8558
Tel : +81-3 – 3431 – 1625 (KEY) ; Fax : +81-3 – 3433 – 4922
e-mail : overseas.sales@tokyokeiso.co.jp ; URL : https://www.tokyokeiso.co.jp
6TG-F1022-E02