Type CB

For the increased reduction of noise in circular ducts, galvanised sheet steel construction

Circular silencers made of galvanised sheet steel for the reduction of noise in circular ducts of air conditioning systems, with increased insertion loss due to sound absorbing pod

  • Absorption material is non-combustible mineral wool with RAL quality mark, biosoluble and hence hygienically safe according to the German TRGS 905 (Technical Rules for Hazardous Substances) and EU directive 97/69/EC
  • Mineral wool faced with glass fibre as protection against erosion due to airflow velocities up to 20 m/s
  • Casing, perforated inner duct and pod are galvanised sheet steel
  • Pod with domed end upstream to reduce the differential pressure
  • Variant with spigot has a groove for a lip seal, suitable for circular connecting ducts to EN 1506 or EN 13180
  • Insertion loss measured according to ISO 7235
  • Casing air leakage to EN 15727, class B


Optional equipment and accessories

  • With flanges on both ends
  • Lip seal

Circular silencer Type CB 00131781_0


  • Application
  • Description

Application

  • Circular silencers Type CB for the reduction of air-regenerated noise in the circular ducts of air conditioning systems
  • For the reduction of air-regenerated noise
  • For the reduction of fan noise

Special features

  • Insertion loss measured according to ISO 7235
  • Increased insertion loss due to sound absorbing pod
  • Pod with domed end upstream to reduce the differential pressure
  • Absorption material is non-combustible
  • Insulation thickness 50 mm or 100 mm

Nominal sizes

  • 250, 315, 400, 450, 500, 560, 630, 710, 800, 900, 1000 mm

Variants

  • 050: Circular silencer with 50 mm insulation
  • 100: Circular silencer with 100 mm insulation
  • CB ../VF1: Circular silencer with flange on one end (end with domed cap)
  • CB ../VF2: Circular silencer with flanges on both ends

Parts and characteristics

  • Casing
  • Perforated inner duct
  • Sound absorbing pod

Accessories

  • Matching flange for one end
  • Matching flanges for both ends
  • With lip seals on both ends

Construction features

  • Circular casing
  • Spigot suitable for circular ducts to EN 1506 or EN 13180
  • Spigot with groove for lip seal
  • Operating pressure up to 1000 Pa
  • Max. operating temperature 100 °C

Materials and surfaces

  • Casing, perforated inner duct and pod are galvanised sheet steel
  • Lining is mineral wool


Mineral wool

  • To EN 13501, fire rating class A1, non-combustible
  • RAL quality mark RAL-GZ 388
  • Biosoluble and hence hygienically safe according to the German TRGS 905 (Technical Rules for Hazardous Substances) and EU directive 97/69/EC
  • Faced with glass fibre as protection against erosion through airflow velocities up to 20 m/s
  • Inert to fungal and bacterial growth

Standards and guidelines

  • Insertion loss measured according to ISO 7235
  • Casing air leakage to EN 15727, at least class B

Maintenance

  • Maintenance-free as construction and materials are not subject to wear

Technical information

Technical data, Quick sizing, Specification text, Order code, Related products

  • Technical data
  • Quick sizing
  • Specification text
  • Order code

Nominal sizes

250 – 1000 mm

Operating pressure

1000 Pa max.

Operating temperature

100 °C max.


CB050 (insulation thickness 50 mm), insertion loss

Nominal size Nominal length Centre frequency fm [Hz]
Nominal size Nominal length 63 125 250 500 1000 2000 4000 8000
Nominal size Nominal length De
Nominal size mm Hz

250

500

1

3

6

11

17

20

23

23

250

1000

3

5

9

18

42

48

47

35

250

1500

5

7

10

23

50

50

50

44

315

500

1

3

5

10

15

17

18

18

315

1000

2

5

8

15

40

42

36

27

315

1500

5

6

8

19

50

50

50

34

400

500

1

2

5

8

13

15

14

13

400

1000

2

4

6

12

38

35

28

20

400

1500

5

5

7

15

50

50

39

25


CB100 (insulation thickness 100 mm), insertion loss

Nominal size Nominal length Centre frequency fm [Hz]
Nominal size Nominal length 63 125 250 500 1000 2000 4000 8000
Nominal size Nominal length De
Nominal size mm Hz

250

500

2

5

10

17

24

23

26

24

250

1000

5

10

17

30

47

50

50

36

250

1500

7

14

22

41

50

50

50

44

315

500

2

5

9

16

21

20

21

18

315

1000

4

9

15

27

44

45

39

27

315

1500

7

12

20

37

50

50

50

34

400

500

1

4

8

14

18

17

16

14

400

1000

3

7

13

25

40

38

29

21

400

1500

6

10

17

33

50

50

40

26

450

500

1

4

7

14

16

16

14

12

450

1000

3

7

12

24

39

35

26

18

450

1500

5

9

16

31

50

50

36

23

500

500

1

3

7

13

16

15

13

11

500

1000

2

6

12

23

38

33

24

17

500

1500

5

9

16

30

50

50

33

21

560

500

1

3

6

13

15

14

11

10

560

1000

2

6

11

22

36

31

21

15

560

1500

4

8

15

30

50

48

29

19

630

500

1

3

6

12

15

13

10

9

630

1000

2

5

11

21

34

29

19

13

630

1500

4

8

14

29

50

44

26

16

710

500

1

3

6

12

14

12

9

8

710

1000

2

5

10

20

33

27

17

12

710

1500

4

7

13

28

50

41

23

14

800

500

1

2

5

11

13

11

8

7

800

1000

2

5

9

19

31

25

14

10

800

1500

3

6

13

26

49

37

20

12

900

500

1

2

5

10

13

10

7

6

900

1000

2

4

9

18

30

23

13

9

900

1500

3

6

12

24

47

34

17

11

1000

500

1

2

5

10

12

10

6

5

1000

1000

2

4

8

17

29

22

12

8

1000

1500

3

6

11

23

45

33

16

10


CB, differential pressure and air-regenerated noise

Nominal size V LWA Nennlänge [mm]
Nominal size V LWA 500 1000 1500
Nominal size V LWA ∆pst
Nominal size l/s m³/h dB(A) Pa

250

190

684

34

14

18

25

250

385

1386

51

55

75

95

250

480

1728

56

85

115

150

250

575

2070

60

120

165

210

315

305

1098

35

14

18

25

315

610

2196

52

50

95

120

315

765

2754

57

80

105

130

315

915

3294

61

115

145

180

400

495

1782

36

12

16

20

400

990

3564

52

50

60

75

400

1240

4464

58

75

95

115

400

1485

5346

62

110

135

165

450

630

2268

36

12

16

20

450

1255

4518

53

50

60

70

450

1570

5652

58

75

90

110

450

1885

6786

63

107

130

155

500

775

2790

36

12

14

18

500

1550

5580

53

45

55

65

500

1940

6984

59

70

85

100

500

2330

8388

63

100

125

150

560

975

3510

37

12

14

18

560

1950

7020

53

45

55

65

560

2435

8766

59

70

85

100

560

2925

10530

63

100

120

140

630

1235

4446

37

12

14

16

630

2470

8892

54

45

55

65

630

3090

11124

59

70

80

95

630

3705

13338

64

100

115

135

710

1570

5652

37

12

14

16

710

3140

11304

54

45

50

60

710

3925

14130

59

70

80

95

710

4710

16956

64

95

115

135

800

1995

7182

37

12

12

14

800

3990

14364

54

45

50

60

800

4990

17964

60

70

75

85

800

5985

21546

64

95

110

125

900

2530

9108

38

12

12

14

900

5055

18198

54

45

50

55

900

6320

22752

60

65

75

85

900

7585

27306

64

95

105

120

1000

3125

11250

38

12

12

14

1000

6245

22482

55

45

50

55

1000

7805

28098

60

65

75

85

1000

9370

33732

64

95

105

120


Circular silencers with sound absorbing pod for better acoustic performance, rigid construction, for air conditioning systems, available in 11 nominal sizes.

Insertion loss measured according to ISO 7235.

Casing with acoustic and thermal insulation.

Optimised differential pressure due to the sound-absorbing pod with domed end upstream.

Various types of connection, suitable for circular ducts to EN 1506 or EN 13180.

Casing air leakage to EN 15727, class B.

Special features

  • Insertion loss measured according to ISO 7235
  • Increased insertion loss due to sound absorbing pod
  • Pod with domed end upstream to reduce the differential pressure
  • Absorption material is non-combustible
  • Insulation thickness 50 mm or 100 mm

Materials and surfaces

  • Casing, perforated inner duct and pod are galvanised sheet steel
  • Lining is mineral wool


Mineral wool

  • To EN 13501, fire rating class A1, non-combustible
  • RAL quality mark RAL-GZ 388
  • Biosoluble and hence hygienically safe according to the German TRGS 905 (Technical Rules for Hazardous Substances) and EU directive 97/69/EC
  • Faced with glass fibre as protection against erosion through airflow velocities up to 20 m/s
  • Inert to fungal and bacterial growth

Technical data

  • Nominal sizes: 250 to 1000 mm
  • Operating pressure: 1000 Pa max.
  • Operating temperature: 100 °C max.

Sizing data

  • D _______________________ [mm]
  • H _______________________ [mm]
  • Insulation thickness __________ [mm]
  • V _______________________ [m³/h]
  • De at 250 Hz ________________ [dB]
  • Δpst _______________________ [Pa]

00107077_0

 Type
CB        Circular silencer with pod

 Insulation thickness [mm]
050       50
100       100

Nominal size [mm]
250
315
400
450
500
560
630
710
800
900
1000

 

 Length [mm]
500
1000
1500

 Matching flange
       No entry: none
GE       on one end (only VF1)
GZ       on both ends (only VF2)

 Type of connection
       No entry: spigot
VD2       Spigot with lip seal on both ends
       (up to nominal size 800)
VF1       Flange on one end
VF2       Flanges on both ends

Order example: CB100/315×1500/GZ/VF2

Insulation thickness

100 mm

Nominal size

315 mm

Length

1500 mm

Matching flange

Both ends

Type of connection

Flanges on both ends




 

Variants, Dimensions and weight

  • Variants
  • Dimensions and weight

CB

Variant

  • Circular silencer for the reduction of noise
  • Spigot

CB/.../VF1

Variant

  • Circular silencer for the reduction of noise
  • Spigot on one end to make connections to the ducting
  • With flange on one end to make a detachable connection to the ducting

CB/.../VF2

Variant

  • Circular silencer for the reduction of noise
  • With flanges on both ends to make detachable connections to the ducting

The tables show the available nominal sizes

CB, dimensions

Nominal size
CB-050
ØD3
mm
CB-100
ØD3
mm
ØD
mm
ØD1
mm
ØD2
mm
n
T
mm
250 349 449 249 283 303 6 4
315 414 514 314 352 378 8 4
400 499 599 399 438 464 8 4
450 648 448 488 514 8 4
500 698 498 538 564 8 4
560 758 558 600 634 12 4
630 828 628 670 704 12 4
710 908 708 750 784 12 4
800 998 798 840 874 16 4
900 1098 898 940 974 16 4
1000 1198 998 1041 1075 16 4


CB, lengths

Nominal length
mm
LN
CB
L
mm
CB/.../VF1
L
mm
CB/.../VF2
L
mm
L1
mm
500 500 490 480 380
1000 1000 990 980 880
1500 1500 1490 1480 1380


CB, weights

Nominal size
CB-050
500
m
kg
CB-050
1000
m
kg
CB-050
1500
m
kg
CB-100
500
m
kg
CB-100
1000
m
kg
CB-100
1500
m
kg
250 10 17 24 12 21 31
315 12 21 30 15 26 37
400 16 27 38 19 32 46
450 21 35 50
500 22 38 56
560 26 44 62
630 30 49 69
710 33 55 77
800 37 61 86
900 40 68 95
1000 45 75 105


CB/.../VF1, weights

Nominal size
CB-050
500
m
kg
CB-050
1000
m
kg
CB-050
1500
m
kg
CB-100
500
m
kg
CB-100
1000
m
kg
CB-100
1500
m
kg
250 11 18 25 13 22 32
315 14 22 31 16 27 38
400 17 28 39 20 33 47
450 22 36 51
500 24 40 58
560 28 46 64
630 32 51 71
710 36 58 80
800 40 64 89
900 43 71 98
1000 49 79 110


CB/.../VF2, weights

Nominal size
CB-050
500
m
kg
CB-050
1000
m
kg
CB-050
1500
m
kg
CB-100
500
m
kg
CB-100
1000
m
kg
CB-100
1500
m
kg
250 11 18 25 13 22 32
315 15 23 32 17 28 39
400 19 30 41 22 35 49
450 24 38 53
500 25 41 59
560 30 48 66
630 35 54 74
710 38 60 82
800 43 67 92
900 47 75 102
1000 52 82 113


Installation details, Basic information and nomenclature

  • Installation details
  • Basic information and nomenclature

Installation and commissioning

  • Any installation orientation
  • Installation in ducts outside of closed rooms requires sufficient protection against the effects of weather

Principal dimensions

ØD [mm]

Outer diameter of the spigot

ØD₃ [mm]

Outer diameter of circular silencers

L [mm]

Length of attenuator/silencer including spigot (in airflow direction)

L₁ [mm]

Length of acoustic cladding and acoustically effective length

B [mm]

Attenuator width and duct width (upright splitters)

H [mm]

Attenuator height and duct height (upright splitters)

T [mm]

Splitter thickness

S [mm]

Airway width

n [ ]

Number of flange screw holes

m [kg]

Weight

Nomenclature

fm [Hz]

Octave band centre frequency

LWA [dB(A)]

A-weighted sound power level of air-regenerated noise

De [dB]

Insertion loss

V [m³/h] and [l/s]

Volume flow rate

Δpst [Pa]

Static differential pressure


All sound power levels are based on 1 pW.


All values were measured in a TROX lab and to EN ISO 7235. Intermediate values may be achieved by interpolation.


Lab measurements exceeding 50 dB are indicated as 50 dB, in line with common practice.

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Contact

Thank you for your message!

Visual contact Visual contact

Your message is send and will be processed shortly.
Our department for Service-Requests will contact you asap.
For general question regarding products or services you can also call:
Tel.: +44 (0)1842 754545 | Fax: +44 (0)1842 763051