Pipeline ancillaries

Disc, split disc and wafer check valves

Dimensions/weights (approximate) in mm and kg

Size

DN15

DN20

DN25

DN32

DN40

DN50

DN65

DN80

DN100 184.0 154

A

B

C

D

E

F

Weight

60.0

43

69.5

53

80.5

63

90.5

75

38 16.0

29.0

15

0.13

45 19.0

35.7

20

0.19

55 22.0

44.0

25

0.32

68 28.0

54.5

32

0.55

101.0

85

115.0

95

142.0 115

154.0 133

0.74

93 40.0

77.0

50

1.25

113 46.0

97.5

65

1.87

128 50.0 111.5

80

2.42

148 60.0 130.0 100

3.81

79 31.5

65.5

40

A

Kv values

DN

15

20

25

32

40

50

65

80 100

Kv

4.4

6.8 10.8 17

26

43

60

80

113

For conversion: Cv (UK) = Kv x 0.963 Cv (US) = Kv x 1.156

Opening pressures in mbar

Differential pressures with zero flow for standard and high

temperature springs.

Flow direction

DN

15

20

25

32

40

50

65 80 100

25

25

25

27

28

29

30 31 33

22.5 22.5 22.5 23.5 24.5 24.5 25 25.5 26.5

20

20

20

20

20

20

20 20 20

Where lowest opening pressures are required, valves without

springs can be installed in vertical pipes with bottom-to-top flow.

B

E

F

C

D

Without spring

2.5

2.5 2.5 3.5 4.0 4.5

5

Heavy duty springs approximately 700 mbar

5.5

6.5

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Pressure loss diagram

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Safety information, installation and maintenance

Pressure loss in bar

Various options are denoted by a marking on the valve body:-

Pressure loss diagram with open valve at 20°C. The values

indicated are applicable to spring loaded valves with horizontal

flow. With vertical flow, insignificant deviations occur only within

the range of partial opening.

'N'

– High temperature spring

'W'

– Without spring

'H'

– Heavy duty spring

'V'

– Standard spring

The curves given in the chart are valid for water at 20°C. To

determine the pressure for other fluids the equivalent water volume

flowrate must be calculated and used in the graph.

Vw =

1000

x V

– Standard metal disc

– Standardmetaldisc

– Standard metal disc

– Viton soft faced disc

– EPDM soft faced disc

– Viton soft faced disc

– EPDM soft faced disc

– Viton soft faced disc

– EPDM soft faced disc

If a product which contains a Viton component has been subjected

to a temperature approaching 315°C or higher, then it may have

decomposed and formed hydrofluoric acid. Avoid skin contact and

inhalation of any fumes as the acid will cause deep skin burns and

damage to the respiratory system. Viton must be disposed of in a

recognised manner as stated in the Installation and Maintenance

Instructions (IM-P134-08). No other ecological hazard is anticipated

with the disposal of this product providing due care is taken.

For full details see the Installation and

Maintenance Instructions (IM-P134-08)

supplied with the product.

DCV disc check valves must be fitted

in accordance with the direction of flow

arrow indicating correct fluid flow

direction. When fitted with a spring they

can be installed in any plane. When

supplied without a spring they must be

fitted in a vertical flow line with the flow

from bottom-to-top.

The 'cam' design of the body allows

the various flange types to be

accommodated. The body is rotated to

touch the flange joint bolts ensuring

that the valve is centred in the pipeline.

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*Note:

Flanges, bolts (or studs), nuts and joint gaskets are to be

provided by the installer. Disc check valves are non-maintainable

(no spares are available). Disc check valves are not suitable for use

where heavily pulsating flow exists, such as close to a compressor.

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Where: Vw

V = Volume of fluid l/s or m3/h

'E'

– Standard spring

'WV' – Without spring

'WE' – Without spring

'HV' – Heavy duty spring

'HE' – Heavy duty spring

'T'

– Valves tested to EN 12266 rate D

No identification indicates a standard spring with a metal disc.

= Equivalent water volume flow in l/s or m3/h

= Density of fluid kg/m3

Disposal

Pressure loss information for steam, compressed air and gases is

available from Spirax Sarco.

How to order

Example: 1 off Spirax Sarco DN50, DCV3 austenitic stainless steel

disc check valve for fitting between EN 1092 PN25 flanges.

DCV3 and DCV3LT Disc Check Valves

TI-P134-50 ST Issue 7

7.6.4

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