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A LEADER IN DAMPER TECHNOLOGIES

PERFECT DAMPER TECHNOLOGIES FOR INDUSTRIAL PLANTS

Louvre dampersDouble louvre dampersTandem louvre dampersfor power stations,FDG and DeNOx plants


Technology leadthrough patented innovations

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The illustration below shows the shut-off damper for DeNOxreactor at the Theiss 2000 power station in Austria with anominal size of 10,000 x 9,000 mm. The damper has beenexecuted using the new LATTICE SUPPORTED BLADES.

The illustration above shows a shut-off damper for theDeNOx reactor at the STEAG power station Herne 4.With a nominal size of 16,000 x 17,000mm, it is to date theworld's largest shut-off damper.

RAUMAG-JANICH can call on over 40 years ofexperience in the field of industrial valve construc-tion. Special consideration has been given to dri-ving the development of louvre dampers and tan-dem dampers in collaboration with our custo-mers. At the beginning of the 80's, the first everso-called free-floating shell blade was developedwhich also excelled itself at high gas tempera-tures due to its low warp characteristic. Bladelengths of 5000 mm and correspondingly largewidths could thus be achieved. This enabled, inthe case of large nominal sizes, considerable sim-plification of the construction and substantialimprovement in reliability.

In 1995, RAUMAG-JANICH developed theLATTICE SUPPORTED blade with which theproblem of warping was entirely solved. Theblade now consisted of two parts with differentfunctions. The supporting function and the trans-mission of the positioning forces are performedby the LATTICE SUPPORT with stub shafts oneach side. The blade plate (the actual blade itself)performs the regulation and shut-off functions. Inso doing, the blade plate is free-floating and gim-bal-mounted on the LATTICE SUPPORT so thateven at high temperatures and long blade lengthsno warping occurs. Blade lengths of 17,000 mmhave already been executed for operating temper-atures upwards of 700°C. Cross-sectional losshas been reduced to 7%.

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Louvre dampers, double louvredampers and tandem louvredampersare deployed for shutting off andregulating flue gas flows. These aredesigned in circular or rectangularform according to the installedsituation. A defined number of damperblades determined by the duct cross-section and damper function arearranged in a robust flanged frame.With shut-off dampers, the number ofblades should in principle be kept toa minimum to keep the sealing lengthas short as possible. In the case ofregulating dampers and specialinstallation situations the number ofblades is determined in line withrequirements.

The schematic illustrations on theright show the most conventionaldamper executions:Louvre dampers, co-rotatingAll blades rotate in the same direction.Deployed as a regulating or shut-offdamper.Double louvre dampersDeployed as shut-off dampers withpurge air for 100% closure, also usedas safety or regulation dampers.Louvre dampers, contra-rotatingUse as regulating dampers with verygood control characteristics. Alsodeployed to homogenise flow and asshut-off valves.

For utilisation in flue gas desulphur-isation plants or in other chemicallyaggressive media, the dampers canbe produced in stainless steel or withchemical resistant coatings.There are also proven deigns availablefor use with unscrubbed flue gas inDeNOx plants. The damper bladedrive can take the form of electric,pneumatic or hydraulic actuators. Inthe case of special drives, all damperscan be designed as fast-opening orfast-closing safety dampers.

Tandem louvre dampersAs with the double louvre damper,tandem dampers are deployed for100% shut-off. Only one blade planeis necessary, however, thus halving thenumber of bearings, packing glands,shafts and rods required.Tandem dampers can also be contra-rotating to achieve optimum regulationcharacteristics.Louvre dampers in conjunction withthe new NICROFLEX HIPERFORMsealing system achieve a high degreeof permanent leak-tightness even withthe largest dimensions of blade. Thesurface area equivalent sealing is99.98%.Double louvre dampers and tandemdampers with purge air enable a100% shut-off in accordance with UVV(periodic accident prevention inspec-tion).


Louvre dampers

Double louvre dampers

Louvre dampers,contra-rotating

Tandem louvre dampers

Resistance coefficient for louvredampers

Flow curve for louvre damperswithout allowance for pipelineresistances

Technical data: T = 350°CDeltaP = 30mbarW =18m/s

Damper shaft bearingsand sealing

Damper shaft bearingsLong years of experience in the most diverse areas ofdeployment have led in particular to the followingdesigns being utilised depending on application.

Ring bearing, outerand maintenance-free, suitable for high temperaturesand unscrubbed flue gas.

Swivel bearingin special, dust-tight encapsulated housings, virtuallymaintenance-free. Neither the medium nor environmentalinfluences can damage these bearings. Even strongvibration cannot lead to bearing damage.

Ball bearingouter, economical solution. Where the damper shafts aresubject to vibration and longer idle periods, the bearingsurfaces can be destroyed.

Centre bearingsfor the damper shafts within the duct. These bearingsare unsusceptible to dust, are maintenance-free and canbe utilised at high temperatures.

Cap bearingfor the damper shafts opposite the drive side. All otherbearings can be utilised optionally for this.

Shaft entry sealsThe damper shafts are sealed off at the housing entriesby means of packing glands. The packing glands canalso be executed with spring-loaded adjustment.

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Ring bearing, outer

Swivel bearing

Ball bearing Centre bearings Cap bearing


Drives and arrangementApart from manual drives, any desiredform of drive can be supplied.All drives equipped with limit switches,torque switches, potentiometers and/orswing angle measurement transducersas required.

Safety drivesAll shut-off and regulation dampers arefitted with fast closing or fast-openingdrives if required.The drive can be designed so that thedamper opens or closes in the case ofpower loss or when a specific operatingparameter is reached.In such cases the opening and closingis effected by springs, drop-weights orpneumatic pressure accumulator.

Drives for louvre dampers

Rod arrangementThe rod arrangement effects a specificdirection of blade rotation and thereforea specific regulation characteristic.However, due to flow engineering con-siderations, different rod arrangementsare executed.The connection to the damper leversis by means of maintenance-free balljoints to enable free movement to bemaintained even during temperaturefluctuations. The rods can also beequipped with expansion compensationfor strong temperature differentialsbetween the housing and rods (page 11).

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Rod arrangement for louvre dampers

Electric drive, open, close and regulation drive

Electric drive

Electric shaft-mounted drive, open, close and regulationdrive,

hydraulic and pneumatic drives also as rotary drives andfor regulation.

Duplex rods for co-rotating movement

Rods for contra-rotating movement

Rods for co-rotating movement


The standard sealing system

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RAUMAG-JANICH has developed proven sealingsystems for the most diverse applications. Figs. 1 – 6show standard seals which are applied according to theleak-tightness required and deployment conditions.

Sweeping blade (Fig. 1)for regulating dampers with no or with low demand onleak-tightness.

Straight abutting blade (Fig. 2).for abrasive media, low leak-tightness

Inclined abutting blade (Fig. 3)for strongly dust-laden media, low leak-tightness.

Adjustable butting strip (Fig. 4)for strongly abrasive media and media with a caking ten-dency, for increased leak-tightness.

NICROFLEX Type MLS (Fig. 5)(metal leaf seal)Leaf seal from stainless spring steel lamellae for high-levelleak-tightness.Not suitable for high flow velocities or regulating operation.The blades can be destroyed by self-oscillation.

NICROFLEX Type MLO (Fig. 6)(metal loop seal)This proven special seal has been deployed in powerstations and cement works in flue gas flows since 1971.The sealing elements consist of elastic stainless steelloops.Even after longer periods of stress these resume their orig-inal form. Caking and encrustations loosened themselvesdue to the shape alteration when closing. A high level ofleak-tightness is achieved.

Fig. 1 Fig. 2 Fig. 3

Fig. 4 Fig. 5 Fig. 6

The worldwide patented NICRO-FLEX HIPERFORM sealing system

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RAUMAG-JANICH developed their new NICROFLEXHIPERFORM Type NHI sealing system specifically for shut-offdampers and gas diverters in gas turbine plants and forlarge-scale flue gas valves.This sealing system originated from the further developmentof the NICROFLEX Type MLO sealing system, proven since1971 (Fig. 6 on the previous page).The geometric form of the circular metal loop permits highpermanent elasticity of over 30mm and even more in thecase of larger loop diameters. By this means, even largerunevennesses and thermal expansion of large-format damperblades are well compensated for.In the unstressed state (when the valve is open), the internalV-shaped clamping strip gives the loop additional lateralsupport (opposite, top). This prevents it from being destroyedby self-oscillation even at high flow velocities or strongturbulence.

In the closed state (opposite, centre), there is a broad contactzone between the seal and counter-flange. This facilitates aparticularly high degree of leak-tightness. The lateral free-standing areas of the sealing loop are thus circularly convexand therefore do not yield even at high pressures.The inner V-shaped rail also limits the spring travel and thusprevents any undesirable overstressing of the seal. By simplyfitting one or more spring plates inside the interior of the sea-ling loop, the spring force can be well matched to require-ments. Even in the case of point deformation due to foreignbodies, the seal regains contact with the mating surfacewithin a short distance. The shape alteration on closingcauses any caked dust or encrustation to loosen itself.

Double seal seating and purge air – with one sealingsystem 100% gas-tight

The illustration on the left shows the new seal system in con-tact with a double seal seating which is in the form of a purgeair duct with a longitudinal slot. This is facilitated by the widecontact surface which is created in the closed state.


No thermal distortion plus energysavings due to the lattice supportedblade DBP

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Lattice supported blades

Shell blades

The illustrations below show an example of adouble louvre damper comparing the flowcharacteristics of shell blades and latticesupported blades. In the open position, theshell blades form a displacement body andtake up close to 1/3 of the duct cross-section.By contrast, the flow passes through the lat-tice supported blades causing only a slightcross-sectional loss of approx. 7%.Particularly in the case of dampers which arepermanently open during plant operation,this facilitates enormous energy savings dueto the lower pressure loss.

Due to its design, the lattice supported blade preventsthermal distortion such as occurs with conventionallybuilt blades. On this point, see page 2 andthe illustrations below and centre right.

Low transportation costs due tocontainer orientated modularconstruction (Patent applied for)

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Louvre dampers and tandem dampersin large-scale nominal sizes involve hightransport costs. With cross-country HGVtransport, this is down to the extra wideload. With maritime transport, the uneco-nomical ratio of weight to required loadingsurface leads to high costs.On top of that, the costs of special cratingfor transport by sea are very high.

RAUMAG-JANICH has, for these rea-sons, developed a modular constructionfor louvre dampers and tandem damperswhich facilitates simple dismantling andreassembly of the individual modules afterthe trial runs in the factory. The individualmodules can thus be fitted in with eachother to save space for transportation.To this end, the damper consists of fourframe elements and the damper blades.The connections between the blades andthe shafts are easily detachable “plug in”connections. The shafts remain connectedto their respective frame elements so thatonly the plug connections have to be madeduring reassembly on site.The drive side frame element carries thedrive shafts, the levers, the connectingrods and the drive, by which means, evenafter dismantling, the functionality andsettings of the limit switches remain intact.The corner connections of the damperframe are first bolted together on site thenwelded gas-tight with a short sealingseam.

The lattice support design of the damperblade, in conjunction with the highly elasticnew sealing system NICROFLEX-HIPER-FORM DBP, permits large-scale bladespans. For this reason, the louvre dampersand tandem louvre dampers can beexecuted without centre bearings in theduct. They are therefore less fault-proneand simpler in their construction thanconventional designs. The individualmodules, damper blades and frameelements, can be fitted together into unitsfor container transport as shown in theillustration on the right. The sub-assembliesare secured with simple transportfastenings. This leads to a considerablereduction of packaging and transportcosts.



Louvre dampers

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Illustration above:Two louvre dampers NS 6200 x 6200 mm undergoingleak-tightness testing at the Rauenstein works. Suppliedfor the flue gas desulphurising plant at the Boxbergpower station. The dampers are operated by a hydrau-lic drive with an emergency operation feature.

Illustration left:Louvre damper NS 6400 x 6400 mm.Material: inconel 625The opening time is adjustable between 0.5 and 10secs.Each blade is driven separately and opens withoutexternal power. Supplied for the bypass in the FGDat the Badenwerk power station.

Illustration top left:Louvre damper NS 8220 x 5300 mmsupplied for the FGD at theJänschwalde power station.

Illustration top, right:Louvre damper DN 5600 mm withNICROFLEX sealing system.Rating: t = 400 °C, p diff. 90 mbarMaterial: 15 Mo 3.Supplied for the DeNOx plant in theSTEAG power station Herne.

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Illustration above:Louvre damper NS 9000 x 10000 mm, supplied for theDeNOx plant at the THEISS 2000 power station inAustria. It serves to close off the reactor. Due to the highflue gas temperature and the large nominal size, thedamper blades have been executed in the lattice supportdesign.A considerable advantage also arises from the low flowresistance (approx. 7%) in normal operation with the valveopen.

Illustration below:In the case of louvre dampers, the individual forcetransferring levers are connected with adjustableball-jointed rods. This facilitates the precise settingand guiding of the damper blades.For high flue gas temperatures, these rods are fittedwith expansion compensation (spring pots) asotherwise the damper blades would move in anuncontrolled manner in the end position due to thedifference in thermal expansion between the dam-per housing and the cold rods.This can lead to an untight closure


Louvre dampers


Double louvre dampers

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Illustration left:Double louvre damper NS 4400 x 4000 mmwith chemically resistant coating.Supplied for the FGD VEW power station,Gersteinwerk.

Double louvre damper NS 6780 x 5390 withNICROFLEX-HIPERFORM DBP sealing systemand purge air, 100% leak-tight closure inaccordance with UVV (periodic accident pre-vention inspection).Supplied for the RWE STEAG power stationVoerde within the scope of a plant renovationand modernisation project.

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Tandem louvre dampers DBP


RAUMAG-JANICH on behalf of ABB-Umwelttechnik in Butzbach, suppliedall shut-off and regulating valves for thenew FGD and DeNOx plant at theTheiss 2000 power station in Austria.This also included the tandem louvredampers NS 4700 x 4700 mm as illu-strated on the left for 100% leak-tightshut-off in accordance with UVV (peri-odic accident prevention inspection).The dampers are fitted with the metal-elastic sealing NICROFLEX Type MLOand MLS sealing system. In the openposition, the flue gas flows through thedamper blades in such a way that thecross-sectional loss and consequentlythe pressure loss is low.

RAUMAG-JANICH supplied, on behalf of LURGI-SMSDenmark, all the necessary shut-off and regulation dampers forthe FDG at the Dolna Odra power station.This supply included one tandem louvre damper NS 6000 x8000 mm, one tandem louvre damper NS 8000 x 5000 mm andeight tandem louvre dampers NS 3070 x 2790 mm as illustratedon the left. While the tandem louvre damper 8000 x 5000 mmwas manufactured entirely from 1.4562 material, the eight tan-dem louvre dampers 3070 x 2790 mm were of a single-sidedexecution in 2.4605 material.

RAUMAG-JANICH supplied four tandem louvre dampersNS 9,000 x 5,000 mm for the FDG at the Jiangyou powerstation in China. The illustration below shows two of the dam-pers during factory assembly at the Rauenstein works.



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Tandem louvre damperNominal size 1980 x 1980 mm for aflue gas desulphurisation plant.Actuation is by means of a safetydrive.The electric drive closes the damperthereby tensioning the springs in thedrive “tree”. A solenoid connects thesprings with the electric drive spindle.In the case of a power failure or safetyincident, the solenoid becomes deadand the springs draw the damperblades into the opened position. In thisposition, the flue gas flows through theblades thus causing only marginalcross-sectional loss. The NICROFLEX-MLO sealing system in conjunctionwith purge air enables a 100% shut-off in accordance with UVV (peri-odic accident prevention inspection).

Illustration above:The electric drive has closed the damperblades and the springs are tensioned inpreparation for a safety incident.

Illustration below:The blades are in the opened position. Thesprings are released. The solenoid hasalready engaged the spindle so that thedamper can be closed by means of theelectric drive.

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RAUMAG-JANICH supplied, for the FDG at theNinghai power station in China, 8 tandem louvre dam-pers NS 11,600 x 5,200 mm. The dampers are moved bypneumatic drives and have a safety function. The aboveillustration shows two dampers during test runs at theRauenstein works.

RAUMAG-JANICH supplied a total of 57 such large-format tandem louvre dampers up to June 2009 forthe FDG plants in power stations in the People'sRepublic of China.

RAUMAG-JANICH supplied the new tandem louvredampers NS 4500 x 4500 mm within the scope ofrelining and renovation of the flue gas desulphurisationplant at the Buschhaus power station. RAUMAG-JANICH's newly developed construction with the gasthrough-flow lattice supported blades DBP wasdeployed in conjunction with the new sealing systemNICROFLEX-HIPERFORM DBP.



Special purpose dampers for

� Power stations� Gasturbine plants� Offshore-Installations� Flue gas desulphurisationplants

� Flue gas denitrificationplants

� Cement plants� Steel smelters� Waste heat recovery plants� Garbage incinerating plants� Chemical processindustries

� Other industrial plants

RAUMAG-JANICH – Perfect technique, Quality and Security

RAUMAG JANICH-SystemtechnikGmbHIm Grund 696528 Rauenstein/ ThüringenTelefon: 0049 36766 881-0Fax: 0049 36766 81032Mail: [email protected]: www.raumag-janich.de

RAUMAG JANICH-SystemtechnikGmbHZweigniederlassung BeckumKirchstrasse 959269 BeckumTelefon: 0049 2525 4141Fax: 0049 2525 6332Mail: [email protected]

Shut-off and modulationdampers

� Shut-off dampers, of roundor rectangular configuration

� Shut-off dampers of hightightness, 99,98% minimum

� Double-shut off dampers,with seal air 100% gastightto UVV

� Tandem dampers, costeconomic alternative to doubleshut-off damper, with seal air100% gastight to UVV

� High efficiency louverdampers, for modulation orshut-off.

� Double louver dampers, withseal air 100% gastight to UVV

� Tandem louver dampers,cost economic and spacesaving alternative to Doublelouver dampers, with seal air100% gastight to UVV

� Lever flap dampers, alsowith double sealing and sealair, 100% gastight to UVV

� Diverter dampers, with doublesealing and seal air, 100%gastight to UVV

� Emergency dampers, fastopening or closing, also on lossof energy

� Stack dampers, also withemergency features

� RK10 sandwich dampers,for fitting between existingflanges

� Dopex shut-off valves� Toggle disc valves, DVGW

approved, as shut-off oremergency dampers

� Hot gas valves, also air orwater cooled

Isolators

� Guillotine dampers for FGDplants. 100% gastight to UVV

� High efficiency guillotinedampers

� Guillotine dampers, withdouble sealing and seal air100% gastight to UVV

� Sickle isolator, 100% gastightto UVV

� Goggle valves, DVGWapproved, 100% gastight toUVV

� High temperature isolators,with or without internal laggingor refractory lining

� High temperature isolators,with air or water cooling

Service and maintenance

� Professional maintenanceof flue gas modulation andshut-off-dampers

� Conversion and moderni-sing of existing flue gasmodu-lation and shut-off dampers

� Upgrading of obsoletesealing systems andoperating systems

Fabrication for industrialmachinery and processindustries� Cooler for dusty bulk materials� Fabricated, welded compo-

nents made of steel andstainless steel, also machinedif required

� Boltless wear liners for cyclo-nes and air separators etc.

Large, tailor designed dam-pers for Gasturbine plants

� Diverter for the isolation, rerou-ting and modulation of the turbi-ne exhaust gas. With doubleseals and seal air 100% gastightin terms of UVV regulations.

� Diverter for gasturbine-off-shoreplants, designed to meet thespecific service requirements.

� Flap dampers, also for modu-lating operations, with seal air,100% gastight in terms of UVVregulations.

� Louver and� double louver dampers for

modulating service and shut-off.� Stack caps, also as� emergency dampers.� Blanking plate Guillotines for

combined cycle plants, also withdouble seals and seal air for100% gastight shut-off in termsof UVV regulations.

� Flexible joints for combinedcycle plants.

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