Total Solutions in Flue Systems

M e t a l o t e r m ® S i l e n c e r sLightweight silencers for flue systems

Product description

Light weight, easy to install!

NL 2:3 1:1,5

GB 1:2

BE 13:15 1:1,15

FR 2:3 1:1,5

DE 3:5 1:1,7

CH 1:1

IT 2:3 1:1,5

FI 11:18 1:1,64

NO 8:11 1:1,375

LV 1:2

PL 5:8 1:1,6

CZ 2:3 1:1,5

GR 2:3 1:1,5

CY 3:5 1:1,7

SE 10:16 1:1,6

Vlaggen

Land Verhouding vlag vlag+outline kleurcodes

2011

C - M - Y - K :0-84-77-32

C - M - Y - K :0-0-0-0

C - M - Y - K :76-50-0-46

C - M - Y - K :100-72-0-18.5

C - M - Y - K :0-0-0-0

C - M - Y - K :0-91-76-6

C - M - Y - K :0-0-0-100

C - M - Y - K :0-15-95-0

C - M - Y - K :0-90-80-5

C - M - Y - K :100-70-0-5

C - M - Y - K :0-0-0-0

C - M - Y - K :0-90-86-0

C - M - Y - K :0-0-0-100

C - M - Y - K :0-100-100-0

C - M - Y - K :0-12-100-5

Pantone 144-C

Pantone 336-C

C - M - Y - K :0-0-0-0

C - M - Y - K :0-100-100-0

C - M - Y - K :0-0-0-0

C - M - Y - K :100-0-100-45

C - M - Y - K :0-0-0-0

C - M - Y - K :0-100-100-0

C - M - Y - K :100-56-0-18.5

C - M - Y - K :0-0-0-0

Pantone Red 032 U

C - M - Y - K :0-0-0-0

Pantone Red 281 U

C - M - Y - K :25-96-84-19

C - M - Y - K :0-0-0-0

#: D4 21 3Dca.10-96-71-1

#: E9 E8 E7

NCS 0580-Y10R

NCS 4055-R95B

Pantone 281 U

Pantone Red 032 U

C - M - Y - K :0-0-0-0

C - M - Y - K :ca.98-99-22-14

C - M - Y - K :0-0-0-0

Ontop has been designing, manufacturing and distributing prefab modular flue systems for over 45 years now. Ontop’s head office is based in Middelburg, the Netherlands and disposes of a very modern ISO 9001 certified production environment as well as testing and designing facilities. With subsidiaries in Germany, France, Poland and Switzerland and importers all over Europe Ontop has a large international network.

With the brand Metaloterm® we bring you a very extensive range of stainless steel single walled, twin walled (insulated) and concentric flue systems. These systems can be used for all kind of applications; as chimney system for fireplaces, wood stoves, open and closed gas fired stoves, as flue system for boilers (condensing/not condensing, negative/positive pressure, cascade formations etc.) or as exhaust system on industrial ovens, bakeries, gas and Diesel engines, turbines etc.

As total solution provider in flue systems we do not only provide flue systems, we also offer our customers an extensive service. This service includes expert technical advice, calculations, 2D and 3D CAD-drawings, testing, knowledge of building standards and legislation and project management. If desired Ontop can take care of the design and delivery on site up to the installation itself.

With the increasing demand for noise attenuation Ontop has developed its own silencer programme. After extensive research and development by Ontop’s own acoustic engineers we now present a unique variety of stainless steel, light weight silencers, all fitting seamless into the existing product range for exhaust gas- and flue systems maintaining the top quality customers are used when purchasing Ontop’s Metaloterm® products.

Table of contentIntroduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3Advantages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4Technical characteristics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5Absorption silencers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6Resonance silencers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8Quarter Lambda silencers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9Combinations of different silencer types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10Pressure loss . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12Questionnaire . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

About Ontop B.V.

3

Insertion loss spectrum of different silencer types

32 63 125 250 500 1000 2000 4000 8000Frequency in Hz

16000

Type - A

Type - R

*depending on requested insertion loss in certain sound spectrum

Type - Q*

IntroductionWhy noise reduction?Typically, the Metaloterm® flues are used in combination with appliances that produce noise. Noice, usually defined as unwanted sounds, is perceived by most people as annoying. Also, the regulations concerning allowed noise levels are becoming stricter throughout Europe. This is why noise reduction is a growing item in many markets. As a total solution supplier in flues and chimneys, Ontop has developed a full range of innovative silencers to meet this demand.

Noise is perceived as annoying, however this is a highly subjective matter. Noise that is irritating to one person, can be perfectly acceptable for another. To overcome this subjective element, noise and noise reduction are measured and described in decibels (dB), corrected for the sensivity of the human ear this is written as dB(A).The dB range starts at 0 (silence) up till 180 dB; the sound at a rocket launching platform during take off. Note: the dB scale is logaritmic; if the dB value increases with 10, the noise power level increases 10-fold!

If the noise level of a source and also the maximum allowed level are known, the necessary noise reduction (and thus the required silencer) can easily be calculated. Alternatively, when the noise level of the source and the reduction of the silencer are known, it is easy to determine the remaining noise level.

Noise comes in different frequencies, noted in Hertz (Hz), that is periods per second. The human ear can distinguish frequencies from

20 Hz up to 10.000/20.000 Hz, depending on age. The frequencies of engines, generators and ventilators vary from approximately 50 to 3000 Hz. The USA standard ASTM E413 describes frequencies 125 to 4000 Hz. The international standard ISO 717 refers to frequencies 100 to 3150 Hz. Ideally, noise reduction is defined in dB, at a defined frequency range.

Important is that different frequencies demand different types of silencers. Higher frequencies can be reduced by absorption of the sound. For this, an absorping material is applied, usually a type of mineral wool. Lower frequencies can be reduced by resonance silencers. For this, the silencer is divided in connected rooms of various dimensions, to reflect and thus reduce the noise. In situations where the velocity of the flue gases exceeds 20 m/s, flow noise will occur. This will influence the sound spectrum. In many installations, the different types are combined to achieve the best results.

Ontop offers a range of absorption (A) as well as resonance (R) silencers.For very low frequencies Ontop offers a special type of reflection silencers, quarter lambda (Q), built to order.In the diagram the performance of the several types of Metaloterm® silencers are shown.

4

AdvantagesWhy Metaloterm® silencers?The obvious advantages of the Metaloterm® flue and exhaust systems are now incorporated in a new silencer programme. Metaloterm® silencers are unique compared to traditional ones which are currently available on the market. The advantages given by the use of Metaloterm® silencers are numerous:• Completelytwinwallandpre-insulated• Allsilencersareequippedwith“click-fix”connectionsatthe

in- and outlet to suit the modular character of the various Metaloterm® systems

• Extremelylightweightproperties,ensuringaweightreductionof up to 50%, compared to traditional heavy mild steel welded silencers

• Duetotheselightweightpropertiesvibrationsarebarelytransferred to surrounding structures

• Allsilencersareconstructedusinghighqualitystainlesssteelmaterials only

• Duetothefactthatanythermalexpansioniscompensatedinside the silencer construction expensive compensators and flexible mounting kits are not necessary

• Metaloterm®’s own standard supports and brackets can be used for installation

• AllMetaloterm® silencers are developed and tested in our own testing facilities according to international standards

It’s obvious that with the above advantages Ontop offers a very time saving, cost effective and high quality solution for any acoustic demand. Especially suited for flue and exhaust systems in buildings and ships.

The Metaloterm® silencer range ensures that over the full frequency range excellent attenuation can be achieved to meet with the applicable standards, whether this is for buildings situated in urban, commercial or industrial areas, or for passenger vessels, commercial ships or even mega yachts.

5

Specification Absorption silencers Resonance silencersInner pipe 1.4404 (316L) 1.4404 (316L)Outer pipe 1.4404 (316L) 1.4301 (304)Thickness (min) 0,5 - 1 mm 0,5 mm - 1 mmInsulation - mineral fibresAcoustical insulation basalt mineral fibres -Thickness 62,5 mm - 137,5 mm 25 mm - 37,5 mm Inner diameter 80, 100, 130, 150, 180, 200, 250, 300, 350, 400, 450, 500, 600(Other or larger diameters on request)

Designations and configuration

Operation mode Wet / Dry

Pressure 5000 Pa

Operating temperature Max. 600 °C

Fuel type Oil/natural gas/calor gas/propane gas/Diesel

Applications Atmospheric gas-fired boilers Condensing heaters and boilers Industrial ovens Industrial ventilation systems Oil-fired appliances Diesel/gas engines (Emergency) power gensets Uninterrupted Power Supply (UPS) Industrial processes

Condensate drain Standard

Orientation Horizontal/vertical

Technical characteristics

6

Metaloterm Absorption Silencers®

0

10

20

30

40

50

60

Noise

redu

ctio

n in

dB

32 63 125 250 500 1000 2000 4000 8000Frequency in Hz

1600025dB 35dB

Minimum guaranteed noise reduction (insertion loss)

at 500 Hz

Insert from diameter 350 mm and up

The tolerance on the measured value is +/- 3 dBThe insertion loss is measured according to ISO 7235: 2003The insertion loss can deviate due to temperature, flue velocity or special installation situations

Type AA typical absorptive type silencer which performs over a broad frequency range in the middle and higher frequencies with excellent performance. As the human ear is sensitive to this less energetic range of frequencies the A type is commonly installed close to the point of termination, this to prevent the sound waves restoring themselves again after the silencer, before entering the atmosphere.

Especially in combination with the R type the noise intensity can be drastically reduced over the full frequency range.

Metaloterm® absorption silencers are divided into two noise reduction levels: 25 and 35 dB. See also the graph below.

Absorption silencers

If more noise reduction is required or larger diameters are requested please contact Ontop. The mentioned dimensions are indicative and may vary in practice.

7

80 205 - 3100 225 - 4130 255 - 7150 275 - 12180 325 - 16200 325 - 20250 375 - 25300 425 - 40350 475 100 55400 525 100 60450 575 175 70500 625 175 93600 725 175 115

80 205 - 5100 225 - 7130 255 - 13150 275 - 17180 325 - 19200 325 - 30250 375 - 35300 425 - 55350 475 100 80400 525 100 130450 575 175 150500 625 175 180600

--

750750

100012501250175017501750200020002000

--

10001000125015001500250025002500300030003000

-600750750

100012501250175017501750200020002000

-100010001000125015001500250025002500300030003000

580580730730980

12301230173017301730197019701970

980980980980

123014801480248024802480297029702970725 175 200

Noise

redu

ctio

n le

vel

Nom

inal

dia

met

er

Diam

eter

out

er p

ipe

Diam

eter

inse

rt

MESI A1ADSI A1 MFSI A1

MESI A2ADSI A2 MFSI A2

Weig

ht

(DN)

Inst

alle

d le

ngth

(IL)

Inst

alle

d le

ngth

(IL)

Inst

alle

d le

ngth

(IL)

(kg)

(DOP

)

(DI)

25 d

B @

500

Hz

35 d

B @

500

Hz

IL

IL

DOP

DOP

DNDN DN

DNDI

Metaloterm® Resonance Silencer

Metaloterm® Absorption Silencer

If more noise reduction is required or larger diameters are requested please contact Ontop. The mentioned dimensions are indicative and may vary in practice.

8

Metaloterm® Resonance Silencers

0

5

10

15

20

25

30

Noise

redu

ctio

n in

dB

32 63 125 250 500 1000 2000 4000 8000Frequency in Hz

16000R silencer min R silencer max

IL

IL

DOP

DOP

DNDN DN

DNDI

Metaloterm® Resonance Silencer

Metaloterm® Absorption Silencer

Ø IL DOP Weight 80 2000 225 25 100 2000 275 30 130 2000 325 40 150 2000 350 45 180 2000 400 50 200 2000 450 55 250 2000 525 60 300 2000 625 65 350 2100 725 160 400 2100 825 190 450 2100 925 205 500 2400 1025 220 600 2400 1225 250

IL = Installed Length, DOP = Diameter Outer Pipe

The tolerance on the measured value is +/- 3 dBThe insertion loss is measured according to ISO 7235: 2003The insertion loss can deviate due to temperature, flue velocity or special installation situations

Minimum guaranteed

noise reduction (insertion loss) on frequency 125 Hz

Resonance silencersType RA typical resonance silencer to neutralize the low frequency noise generated by diesel engines, boilers, CHP units etc. Commonly installed close to the sound generating source preventing the energetic low frequency noise propagating through the full length of the exhaust system.

The guaranteed noise reduction (insertion loss) at 125 Hz is more than 15 dB.

If more noise reduction is required or larger diameters are requested please contact Ontop. The mentioned dimensions are indicative and may vary in practice.

9

Metaloterm® Quarter Lambda Silencers

0

5

10

15

20

25

30

Noise

redu

ctio

n in

dB

32 63 125 250 500 1000 2000 4000 8000Frequency in Hz

16000Q silencer min Q silencer max

The tolerance on the measured value is +/- 3 dBThe insertion loss is measured according to ISO 7235: 2003The insertion loss can deviate due to temperature, flue velocity or special installation situations

Quarter Lambda silencersType QThis special type of silencer (Quarter Lambda) is typically constructed to reduce specific dominant frequencies in a given sound spectrum. Constructed with multiple chambers and baffles

this type of silencer gives excellent results in attenuation in the low frequency spectrum. The Q silencer can be longer and more slender than the R type and therefore offers excellent possibilities for installation in the more tight spaces such as inside ships and shafts.

Dimensions of the Q silencer depend on the given sound spectrum and the requested noise reduction. An example of the possible noise reduction of a quarter lambda silencer is shown in the graph below.

10

Metaloterm® Absorption & Quarter Lambda Silencers

Noise

redu

ctio

n in

dB

32 63 125 250 500 1000 2000 4000 8000Frequency in Hz

16000Type - A + QType - QType - A

60

50

40

30

20

10

0

Metaloterm® Absorption & Resonance Silencers

32 63 125 250 500 1000 2000 4000 8000Frequency in Hz

16000Type - A + RType - RType - A

60

50

40

30

20

10

0

Noise

redu

ctio

n in

dB

The tolerance on the measured value is +/- 3 dBThe insertion loss is measured according to ISO 7235: 2003The insertion loss can deviate due to temperature, flue velocity or special installation situations

Combinations of different silencer typesCombinationsDue to the modular character of the Metaloterm® systems, the various types of silencers can be implemented in one exhaust system resulting in excellent acoustic performance of the total exhaust system. The graphs below show examples of combinations of absorption silencers and resonance or quarter lambda silencers.

Ontop has developed its own acoustic calculations software by which it is possible to calculate either the final noise level by input of the sound spectrum and the silencer type or the needed silencer by input of the sound spectrum and the requested final noise level. All necessary input for these calculations can be given by filling in the questionnaire on page 14.

11

Pressure loss - Metaloterm® Resonance Silencer Pressure loss - Metaloterm® Absorption Silencers

Velocity in m/s

Pres

sure

loss

in P

a

Pres

sure

loss

in P

a

Velocity in m/s

Silencer type R Silencer type A - 25 dB Silencer type A - 35 dB

0

500

1000

1500

2000

2500

3000

5 10 15 20 30 40 50

500

450

400

350

300

250

200

150

100

50

05 10 15 20 30 40 50

Pressure loss - Metaloterm® Resonance Silencer Pressure loss - Metaloterm® Absorption Silencers

Velocity in m/s

Pres

sure

loss

in P

a

Pres

sure

loss

in P

a

Velocity in m/s

Silencer type R Silencer type A - 25 dB Silencer type A - 35 dB

0

500

1000

1500

2000

2500

3000

5 10 15 20 30 40 50

500

450

400

350

300

250

200

150

100

50

05 10 15 20 30 40 50

Pressure loss

Pressure is often a discussion when different units are used. The following comparison may be useful:

Conversion tablePressure N/m² = Pa bar mbar = hPa mm Wk kp/cm² = at Torr atm

1 N/m² = Pa 1 0,00001 0,01 0,102 0,0000102 0,0075 0,00000987

1 bar 100000 1 1000 10200 1,02 750 0,987

1 mbar = hPa 100 0,001 1 10,20 0,00102 0,750 0,000987

1 mm Wk 9,81 0,0000981 0,0981 1 0,0001 0,0735 0,0000968

1 kp/cm² = atm 98100 0,981 981 10000 1 735,5 0,968

1 Torr 133,3 0,001333 1,333 13,6 0,00136 1 0,00132

1 atm 101325 1,013 1013 10330 1,033 760 1

The pressure loss depends mostly on the type of silencer that is used, the diameter of the exhaust system and the amount of volume flowing through.The following table gives an indication of the pressure loss in common situations:

When a silencer is installed in an exhaust system, there will always be a loss of pressure. In other words, the silencer has a resistance which causes additional back pressure to the engine. In most situations, this is not a problem since the maximum allowed backpressure of many engines is much higher, so the engine will easily overcome this resistance.

However, in some installations this may be a point of concern, notably where the engine allows low backpressure, or where the installed exhaust is very long or to small in diameter, which causes

high additional resistance. Certainly, the Metaloterm® elements with smooth inner surface will help to minimalize the resistance of the total system, therefor the pressure loss will seldom be a topic.

But if required, Ontop can provide pressure–loss calculations for any specific situation where our silencers and flues are installed. Obviously, this will only be valid for installations equipped with Metaloterm® products; other products will have unknown effects on the pressure loss.

For Q silencers or silencer combinations pressure loss can be calculated on request.

12

horizontal ceiling

horizontal wall

horizontal floor

vertical ceiling

vertical wall

vertical floor

Installation

The suspension of a silencer can be done in several ways. There are six different configurations (see above). Within these different configurations there are several possibilities. One can work with standard Metaloterm® supports or one can use supports of a different brand or type.

In the latter case Ontop can provide the silencers with universal support brackets.See the next page for the different possibilities. Details of these possibilities or solutions made to order can be obtained at Ontop.Also see our website www.metaloterm.com for all standard solutions.

13

Standard Ontop or other solution Other solution

Above figures show examples of possible solutions. Depending on the weight and the dimensions of a silencer, the fixation can also be done differently. For silencers in a smaller diameter, weighing not more than 3 times the weight of a meter length, (or in case of a single wall system, not more than 6 times), standard mounting materials can be used. Is this case the distance between the supports, as well as the load bearing, has to be adjusted taking into account the extra weight of the silencer. For more information please contact Ontop.

1. Vertical ceiling installation 2. Vertical ceiling installation 3. Horizontal ceiling installation

4. Vertical wall installation 5. Horizontal wall installation 6. Horizontal ceiling installation

7. Vertical wall installation 8. Horizontal wall installation 9. Horizontal floor installation

10. Vertical floor installation 11. Vertical floor installation

14

Company

Contact

E-mail

Mobile

Project ref.

Application

Fuel type

Manufacturer

Type

Date

Contact person at Ontop

Country

Name

Requested quotation date

Applications general data

Volume flow

Mass flow

Temperature

RPM

Maximum allowed backpressure

m³/h

kg/h

°C

rev/min

Pa

m

°

Urban Industrial

Attenuation requirements (please make your choice)Applications acoustic data

Required insertion loss

Required soundlevel directly at the terminal

Required soundlevel directly at the terminal

At distance from the terminal

Angle of measurement

Local surroundings

Nominal inlet Ø

Nominal outlet Ø

Metaloterm® system type

Installation

Position

dB

dB

dB(A)

dB(A)

Marine

Choose between power or pressure

Soundpower spectrum of the source in

Soundpressure spectrum of the source in

Distance and angle to point of emmision

Choose between dB or dB(A)

dB dB(A)

dB dB(A)

m °

Frequency in Hz

Silencer(s)

mm

mm

Inside building Outside building

Horizontal Vertical

Situation sketch

⅓ Octave Single octave Sound level

25

31,5 31,5

40

50

63 63

80

100

125 125

160

200

250 250

315

400

500 500

630

800

1000 1000

1250

1600

2000 2000

2500

3150

4000 4000

5000

6300

8000 8000

10000

Remarks

Questionnaire silencersQuestionnaire silencers

15

References

Project Boxtel, The Netherlands

Project Dassault, Paris, France

Project Lemwerder 2, Tangermünde, Germany

Project Feadship, NB680, The Netherlands

This leaflet has been compiled with great care. No rights can be derived from the content of this document.

www.metaloterm.com

Ontop B.V.Postbus 135, 4330 AC Middelburg Oude Veerseweg 23, 4332 SH MiddelburgNederlandT : +31 (0)118 68 99 00F : +31 (0)118 68 99 99E : info.nl@metaloterm.com

Ontop Abgastechnik GmbHPostfach 1340, 51657 WiehlAlbert-Einstein-Straße 8, 51674 WiehlDeutschlandT : +49 (0)2261 708-0F : +49 (0)2261 708 90 / 708 95E : info.de@metaloterm.com

Metaloterm France S.A.R.L.18, rue des Campanules77185 LognesFranceT : +33 (0)1 64 62 12 30F : +33 (0)1 64 62 11 08E : info.fr@metaloterm.com

Ontop Polska Sp. z o.o.ul. Hallera 7598 - 100 WiewiórczynPolskaT : +48 (0)43 676 33 66F : +48 (0)42 209 10 57E : info.pl@metaloterm.com