Integral type
Differential pressure flowmeter

VTW Series
OUTLINE
VH series Wafer-Cone® differential pressure flowmeterand small sized Variable Area flowmeter are integrated
into one Wafer-Cone® bypass flowmeter. As the meterrequires little straight runs and little head loss compared
to orifice plate, it offers you reduction of construction
cost and energy saving.

FEATURES● Simple installation
Wafer connection makes installation simple. Flowmeter body flanges designed to match the pipe flanges
guide to the pipe center line.
●Measuring fluid● Short straight runs
The required straight runs are less than 1/5 of thoserequired for orifice and vortex flowmeters. The narrow
installation space allows simple and flexible piping
arrangement plan. It leads to space and cost saving.
● Low pressure los
The meter requires smaller pressure loss compared tothe other type of meter at the same flow rate.
● Matching any flow direction
It can measure either horizontal, vertical, upward, or
downward flow. The orientation of the indicator can be
set in a simple way at field.

Water or liquids having equivalent viscosity to water.
Consult Tokyo Keiso about gasmeasurement.
● Fluid pressure
Max. 1.0 MPa● Fluid temperature Max. 120 °C*: It is general data, and themaximum temperature may
change by terms of use andenvironment.
● Accuracy of the reading ±3.0 % of Full Scale● Scale range
10 : 2● Flow direction
Either horizontal, vertical, upward, or downward flow
● Required straight runs
Type of joints● Easy maintenance
The simple and rugged mechanism constructed ofsmall number of parts make maintenance easy.

Upstream side Downstream side

1 piece of 90° bend0D0D2 pieces of 90° bend

0D

0D

bend T joint

0D

0D

STANDARD SPECIFICAION

Butterfly valve(Flow control valve)

3D

3D● Meter size

Butterfly valve (Fully open)

3D

0D

Gate valve (Fully open)

0D

0D

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

1D

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

1D

1D● Connection● Rating● Connection size
● Materials

25, 40, 50, 65, 80, 100 mm
1, 1-1/2, 2, 2-1/2, 3, 4 inch
Wafer type
JIS10K, 20K
ANSI Class150, 300
DIN PN16, 40
GB PN1.6, 4.0
Same as meter size
SCS14A (Detector body)
SUS316 (Cone)Heat-resistant glass (Taperedtube)
O ring (Fluorocarbon rubber)[Notes]· D shows the nominal size of Wafer-Cone flowmeter.
· The required straight runs are the distance from theflange faces of Wafer-Cone flowmeter.
· Add 1D to the above mentioned figures for the service β ratio is 0.65 or more.
TG-F1023-7E
RevisedMay 2016 K
1st edition Jun 2008 K

VTW series Integral type Wafer-Cone® Differential pressure flowmeter

MEASURING RANGE
Meter size/Connection size

Measuring range class 1
Permanent
Scale range
βpressure loss
(m3/h)
ratio(kPa)

Measuring range class 2
Permanentβ
Scale rangepressure loss
ratio
(m3/h)(kPa)

Measuring range class 3
Permanentβ
Scale rangepressure loss
ratio
(m3/h)
(kPa)

25A

1"

DN25

0.26 to 1.3

0.45

8.3

0.6 to 3

0.65

5.6

0.9 to 4.5

0.75

4.5

40A

1-1/2"

DN40

0.8 to 4

0.50

7.3

1.6 to 8

0.65

6.5

2.8 to 140.803.750A2"

DN50

1.2 to 6

0.45

10.5

2.4 to 120.655.2

5 to 250.80

4.365A2-1/2"

DN65

1.6 to 8

0.45

8.8

3.6 to 18

0.65

5.7

7 to 35

0.80

4.0

7 to 35

0.70

5.2

10 to 50

0.80

3.3

10 to 50

0.65

5.8

18 to 900.80

3.680A

3"

DN80

2.4 to 12

0.45

8.2

100A

4"

DN100

4 to 200.45

7.7

The permanent pressure loss is the one at maximum flow rate.

MODEL CODESMODEL CODES
VTW□Materials of detector

1□□□

–□□

□

CONTENTS/□□SCS14A/SUS316

325A

1"

DN25

440A

1-1/2"

DN40

Meter size

550A2"

DN50/Connection size

665A

2-1/2"

DN65

780A

3"

DN80

100A

4"

DN100

8Connection rating

J1JIS10K

J2JIS20K

A2ANSI Class 150

A5ANSI Class 300

G1GB PN1.6G4GB PN4.0

D1DIN PN16

D4DIN PN40

β ratio

– 45

0.45

– 50

0.50

– 55

0.55

– 60

0.60

– 65

0.65

–70

0.70

– 75

0.75

– 80
Measuring range

0.80
1Measuring range class 1

2

Measuring range class 2

3

Measuring range class 3See aforementioned MEASURING RANGE for the relation between measuring range and β ratio.

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

2ANSI

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

DIN

GB

Class300(inch)

PN16(mm)

PN40(mm)

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

25A

1"

DN25

M16×130

M16×140

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

65A2-1/2"

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

TOKYO KEISO CO., LTD.

TG-F1023-7E

VTW series Integral type Wafer-Cone® Differential pressure flowmeter

DIMENSIONS⑧⑨⑩⑪⑫⑬

（200）

①⑤⑥⑦
④

②③

FLOW

（A）

L

● Materials
Materials

Part No. Part name1

Detector body

SCS14A

2Cone

SUS316

34SUS316

SupportFastening screws SUS316L

5

Cock piece

SCS14

6

Cock axis

SUS316

7O-ring

Fluorocarbon rubber

8Indication part

SCS14

9

Tapered tube

Heat-resistant glass

10

Float

Titanium

11

Cover

SUS304/ABS

12

Scale plate

Polycarbonate

13

O-ringFluorocarbon rubber

Wafer-Cone® is registered trademarks of
McCROMETER, Inc.

● Dimension listMeterLsize
(mm)
(mm)

A(mm)

Weight(Approx.)
kg

2557

195

2.2

4076

204

3.2

50

86

210

3.7

65

102

225

5.780

121

240

7.7

100

152

258

12.2

Cautions on the use of glass tube variable area flowmeters

CAUTION
Avoid the use of glass tube variable area flowmeters for thefollowing services.
1. Liquid services subject to impulse pressure in the process.
2. Secondary accidents might occur due to the breakage ofglass in such services :•Toxic fluids such as poisons, stimulant and narcotics•Flammable fluids•Explosive fluids
3. Gas handling process where breakage of glass might resultin gas leakage or scattering of glass fragments.
4. The installation places of the flowmeters where breakage ofglass might be caused by the accidents from the surrounding piping or equipment.
5. On-off operation where breakage of glass might be causedby the collision of the float inside meter due to the abruptchange of flow.
6. Services where the heat shock by abrupt change of temperature is expected.
* 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 : http://www.tokyokeiso.co.jp
TG-F1023-7E

TOKYO KEISO CO., LTD.

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