ibau hamburg flow control gate -...

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I BAU HAMBURGFlow Control Gate

Standard type and variationsfor all applications

I BAU HAMBURG

A member of the HAVER & BOECKER Technology Group

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The I BAU HAMBURG Flow control gate

Flow control gateFlow control gates areused for shutting off thedischarge spouts of silosand for the controlled dis-charge of pulverized bulkgoods such as cement,lime, gypsum and fly ash.IBAU Flow control gatesensure an unrestrict ed flow-through. Thanks to the

design without step, thereis no danger of smalllumps being stopped, thuscausing the through-put todecrease. The pictureshows a standard dis-charge spout containing ahand actuated cut-off gate,a motor actuated IBAUFlow control gate, aflexible compensator anda fluidslide.

Handactuated gateIn general, manual flowcontrol gates equippedwith coupling and leverare used for power actuat -ed gates. This allows toadd a gear motor or pneu-matic piston later on ifrequired. All types of flowcontrol gates are equipped

with a switch box contain-ing three limit switches forthe positions ‘open’,‘intermediate’ and closed’.Furthermore, there is apotentiometer for remotecontrol indication.

Silo discharge with flow control gate

Small lumps passthe flow control gatewithout being stoppedby a step.

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Motoractuated gateMotor actuated flowcontrol gates are equippedwith a gear motoror with a torque motor.Gear motors can bepositioned in four differentways, i.e. ‘top right’,‘top left’, ‘bottom right’and ‘bottom left’.

The standard type is topright. The class of protec-tion for all gear motors isIP 54 according toDIN 40050. The actuat ingvelocities for a full wayof 90 degrees are 8, 25, 45or 60 sec. depend ingon the requirements.

Pneumatic piston-actuated gatePneumatic piston-actuat edflow control gates areequipped with a double-acting pneumatic pistoncontrolled by a special5/3 way valve whichmakes it possible to stopthe gate in any positionrequired.

In case of power failurethe gate will automaticallymove into the ‘closed’position.

Silo discharge with pneumatic piston- and motor-actuated flow control gate

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Schematic illustration of a flow control gate

Flow control gateThe flow control gate isan element to be placedbetween fluidslides (pictu-re on the right). It consistsof an upper box (A) whichforms the conveyingchamber and a lower box(B) which is supplied withcompressed air. Upperand lower box are separa-ted from each other bya fabric perme able to air.

A roller-shaped gate isplac ed with in the upperbox. The roller is sealed byan exchange able gasketand features an adjustableaperture for the flow-through of the bulk goodsto be slowed down.The function of the flowcontrol gate is firstly thedust-tight shut-off of asilo discharge opening andsecondly the infinitely con-trolled dis charge of pul-verized bulk goods froma silo into a conveyingelement (e.g. fluidslide).

This is possible in a sim-ple way. When the rollerrotate s into one direction,the silo discharge open ingis closed, when the rollerrotates into the otherdirection, the adjustableaperture is opened, so thatthe fluidiz ed bulk goodcan flow through.

It is possible to vary thecross-section or size of theaperture which is openedby the rota tion of theroller into one directionor the other. The flow ofbulk material pass ing theroller in creases withincreasing size of the opencross-section; in otherwords the quantity of flui-dized bulk goods leav ingthe silo is controlled.

The opening angle of theflow control gate can beseen from a pointer atta-ched to the shaft coupling.

AperturesDifferent operating con-ditions requirespecially shap ed apertures.

Triangular apertureThis type of cross-section isthe most common andmost appropriate shape fornearly all metering require-ments of average accuracy.

Trapezoid aperturewith drip gapThis type with an extend -ed triangular cross-sectionfor a large flow-throughcapacity is particularlysuited for bulk loading.

For balancing the car loadthe roller is turn ed intoa position which sets freeonly the drip gap.

Aperture for lineardosingA special aperture for lineardosing is available for spe -cial applications, e.g. feed -ing a belt weigher or flowmeter. This specially shapedaperture allow s lineardos ing; i.e. an openingangle of 30° results in athroughput of 30 %.

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Roller of the flow control gate in closed position

Possibilities of attaching the actuator

The flow control gatecan be actuatedeither by a gear motoror by an electricallycontrolledpneumatic piston.

Each standard typehas a disengageablecoupling with handlever for moving theroller in case of a power failure.

Roller of the flow control gate in open position

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The drawing shows an original I BAU Silo with discharge

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Information

sections controlled by I BAU Flow control gates

Flow control gatesfor silo discharge

This is a typical applica -tion of flow control gatesinstalled forcontrolled silo dischargein an IBAU Silo.

The ring-shaped bottomof IBAU Silos can be divi-ded into 4 – 12 sections.

Each section consists offluidizing pads, a cut-offgate and a flow controlgate with flexiblecon nection and a fluid-slide which conveys thedis charged material tothe collecting bin.

The flow control gatesare opened one after theother, the sequence beingcontrolled by a timingsystem. General lyonly one section at a timeis activated for discharge.

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Controlled feeding system with flow metering equipment

Controlledweigher feedingRaw meal metering equipmentplays an important role in thecement production. Prior tofeeding the preheater of thekiln, raw meal extracted froma blending or storage silois continuously weighed bymeans of flow meters.

Often, a weighing bin installedon load cells is used. Thisprebin allow s the control of theweighing system and makes itpossible to keep a constantlevel which in turn ensures apermanent height of raw mealabove the aerated bottom.

Flow control gates control theflow of raw meal between theprebin and the weighing equip-ment. For this type of applica-tion pneumatic operated flowcontrol gates with electropneumatic control device areused. The material flow is con-trolled by a signal exchangewith the flowmeter.

The pneumatic actuators oper-ate according to the principleof rotary paddle pneumaticswithout the use of lever arms,toothed racks and gears. Thisallows the pure torque to betransferred, with no interferingside forces on the square drive.The actuators, which are char-acterised by a compact andweight-saving design, requirelittle or no maintenance.

The actuator device also comesequipped with ventilationoptions, enabling it to be alsomoved manually (hand lever).The flow control gates of thestand-by equipment can be setvia remote control exactly tothe current operating positionof the main line. The figure onthe left illustrate s the arrange- ment of a weighing stationwith flow metering equipment.

Cone silooutlet

Weighingprebin

The I BAUFlow controlgate withpneumaticcontroldevice

Stand-byequipment

The IBAU Screw pumpfor preheather feeding

Flowmeteringequipment

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Flow metering equipmentFlow control gate with pneumatic actuator and control device

Silo outlet with flow control gates, feeding the weighing bin

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Motor actuated flow control gates

Standard typeflow control gatesThe picture showsflow control gates ofsize 800 and size 200,both motor-actuated,with a capacity ofapprox. 1000 t/h resp.150 t/h cement.

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Flow control gatewith pneumaticallycontrolled driveThe pneumatic actuator,is de sign ed for the linearcontrol of the materialthrough put quantity.

A further im portantfeature is the emergencyshut down, i.e. theflow control gate isclosed pneumatic ally incase of a power fail ure.

The setpoint as well asposition feedback arecarrie d out by means ofa 4 –20 mA signa l.

The combination of anydesired type of I BAURoller with a pneumaticactuator, connected to anelectro pneumatic controldevice, is eminentlysuitable forbulk handling, e.g. on thedis charge spouts of silosor bins where a linearlycontrolled dis charge isrequir ed and where,for safety reasons, thedischarge process mustbe stopp ed in case ofpower failure.

Flow control gate with pneumatic actuator

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Flow control gate with motor-controlled drive

Flow control gatewith motor-controlled driveThis type of flow controlgate, also serves for thelinear control of materialsto be discharged fromsilos or bins.

In order to achievea high control accuracy,a slip-on gear motorpositioned di rect ly on theshaft of the roller is usedinstead of con ventionalgear motors with drivingrod and clevis.

Among its advantages arethe space-saving design,an infinite control notrestricted to a certainnumber of positions andan ultimately high controlaccuracy.

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Flow control gate with standard pneumatic actuator

Flow control gatewith controlledpneumatic piston

This flow control gatewith pneumatic piston isactuat ed by a double-acting pneumatic piston

con troll ed by a special5/3-way-valve. The threepositions are ‘open’,‘closed’ and ‘stop’.The ‘closed’-posi tion isthe emergency shutdownposition in case of powerfailure which means thatthe control gate will then

be brought into the ‘shut’-position. The actuat ingvelocity can be adjust edindependently by meansof a throttle muffler. Thelowest possible actuatingvelocity is about 10 sec.for a 90° move.

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Flow control gateType IBN

The I BAU FLOW CON-TROL GATE TYPE IBNshows all advantages andfeatures of the worldwiderenowned I BAU FLOWCONTROL GATE, whichhas been installed morethan 500,000 times.

The variations of the basictype with different actuatorshave in common theextreme ly high accuracyof a controlled flow ofpulverised bulk goodswith reproducible results.

They require practically nomaintenance. However,even good things aresubject to wear after manyyears of good service undersevere conditions.

Different designs of otherflow control gates maymake it necessary to disas-semble the complete unit.However, thanks to thedesign of the I BAU Flowcontrol gate, a completedisassembly becomesunnecessary.

Maintenance can be carriedout without dismantling thecomplete unit. After havingtaken off one of the sideplate s the roller can beremoved. The gasket is thenaccessible and can be repla-c ed if required. Reassemblyis carried out in reverseorder.

I BAU FLOW CONTROL GATETYPE IBN

installed at the silodis charge outlet

I BAU FLOW CONTROL GATETYPE IBN

roller being taken out

Diagrammatic view of a flow control gate

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Information

The I BAU Flow control gate type IBN

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Assembley of flow control gates at the


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I BAU HAMBURG fabrication and assembley shop

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Placing of actuators on a flow control gate

Quality control check at the workshop


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Spare rollers for flow control gates at the I BAU HAMBURG assembley shop

Flow control gates with pneumatic actuators

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I BAU HAMBURG · Rödingsmarkt 35 · D-20459 Hamburg · PHONE +49 (0) 40 36 13 090FAX +49 (0) 40 36 39 83 · Email: [email protected] · Internet: www.ibauhamburg.de

I BAU HAMBURG – THE STATE OF THE ARTWe have designed and built worldwide about 7.000 large capacity silos, 250 multi-compartment silo plants,2.000 pumps for bulk mate rial transport, 250 power plant equipment, 60 terminals for bulk material mixing,100 marine terminals for cement, 30 shipunloaders for cement, and 20 self-unloading cement carriers

Cement silo installation with bulk loadingin Samalayuca / Mexico

High capacity mixing plantHOLCIM, Antwerp / Belgium

Shipunloader on rubber tyres for ContinentalFlorida Materials, Port Canaveral / USA

Raw meal blending silo,Dyckerhoff Zement / Germany

Coal-fired power plantMehrum / Germany

Cement carrierM.V. GLEN VINE

ibau hamburg flow control gate -...

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