Edition 5.99 GB

Competence in gas

Heat treatment systems in the metalworking industry

Continuous roller hearth furnaceWorks photograph Messrs. Schmitz&Apelt LOI

Innovations which pay offSafety, lower energy consumption and ac-tive environmental protection are issues ofutmost importance for operators of industrialfurnaces.

SafetyKromschröder gas control and safety sys-tems often do more than make industrial gasinstallations safe. They provide operatingpersonnel with optimum protection to amuch higher level than is required by therelevant national and international standardsand regulations (Machinery Directive89/392/EEC, Low-Voltage Directive 73/23/EEC,EMC Directive, Industrial Thermal ProcessInstallations DIN-EN 746).

Customised systemsHigh quality in heat treatment processes isachieved with adapted systems designed byKromschröder. Modern components throughto the field bus interface control these sys-tems. Even existing systems can be mod-ernised and extended easily and at low cost.

Straightfoward start-up proceduresKromschröder systems are a key cost-cutting factor because they are easy toassemble and install. Start-up proceduresare accordingly short and straightforward.We also offer special courses of instructionfor various customer and product groups,should you require extra support. Our com-petent Service Team is also there to help.

Optimum price/performance ratioKromschröder offers technically sophisticat-ed concepts for your process engineeringapplications in the metalworking industrywith a favourable price/performance ratio.

High availability due to the very best technology availableand first-class serviceThe design and robust construction of theKromschröder firing systems ensure a long

service life. Preventive maintenance is es-sential for trouble-free operation, high avail-ability and economy. For this reason, theKromschröder Service Team can offer youtailor-made maintenance contracts.

Consumption measurementExact consumption measurements at thegas and air end are now state-of-the-art.Kromschröder offers a new generation offlow meters equipped with the most modernelectronics and optional M-Bus interface.The actual consumption can be read offdirectly.

Simple operationMulti-lingual leaflets and operating instruc-tions and our catalogue on CD-ROM makeit easy for you to operate products from ourdiversified range - from single componentsto all-in systems. You can download up-to-date Kromschröder information from theInternet at any time:

http://www.kromschroeder.de

Walking-beam furnaceWorks photograph Messrs. LOI Thermprocess

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Technical documentation

Catalogue CD-ROM

Bogie hearth annealing furnaceWorks photograph Messrs. Löcher

Furnace atmosphere and temperature distributionUsing Kromschröder impulse firing systemswith air/gas ratio control, it is possible toachieve an homogeneous temperature distri-bution throughout the furnace atmosphere.Based on the efficient counter-current prin-ciple, our burners ensure optimum mixing ofgas and air.

Hot air compensationFlue gas temperatures must be kept as lowas possible if a gas-fired installation is towork with a high level of efficiency. To doso, the heat in the flue gas can be returnedto the process by directing it through heatexchangers in order to raise the tempera-ture of the combustion air.Kromschröder can supply the necessarycontrol valves for gas and air.

Types of gasAll Kromschröder systems are suitable fortown gas, natural gas and LPG. In addition,we can supply a large assortment of reliablegas control valves for sewage gas, landfillgas, biologically produced methane, gener-ator gas and coal gas.

Modular designThe specially coordinated product rangeoffers excellent modular design options. Foryears now, we have been very successful intaking these important steps into the future

of the modular system in firing sys-tems.

Competence in gasOwing to the use of modern technol-

ogies, Kromschröder allows you an in-novative partnership in the metal-working industryWe develop individual solutions inclose cooperation with our custom-ers.

Strip galvanising plantWorks photograph Messrs. Electric-Furnace

Pipework and wiringto American Standard

Automation engineer-ing in the controlcabinet

Gas pressure control system

Burner control system

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Heat treatment systemsin the metalworking industryQualityThe production of high-grade products de-pends to a high degree on the quality of thefiring systems used.Kromschröder is certified as complying withStandard DIN EN ISO 9001 for quality sys-tems. Our organisation and technical pro-cesses and procedures are qualified to de-velop, manufacture and deliver productsand services of assured quality.

Shaft smelting furnaceWorks photograph Messrs. Striko/Westofen

Shaft smelting furnaceWorks photograph Messrs. Marconi

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Directly heated heat treatment plants

Example: Smelting in thealuminium industryStructure of a heating system with continuous control

Function:When the gas pressure control, measuringand safety system (1) is in operation, theburner control system can be placed intooperation.When the automatic burner control unit (15)is enabled, the solenoid valves for gas (3and 4) open. At the same time, the ignitiontransformer (15) is supplied with voltage sothat an ignition spark is produced at theburner nozzle in the burner (7). The motor-ised butterfly valve (12) is in ignition positionso that the ignition air flows to the burner (7).A proportional outlet pressure is producedat the air/gas ratio control (4) via the impulseline. If heat is requested, the motorised but-terfly valve (12) opens continuously. Thiscauses a higher control pressure to act viathe impulse line onto the air/gas ratio con-trol (4) which results in a higher gas outletpressure.The maximum flow rates are limited by theadjusting cock (5) and the air flow rate con-trol valve (13).The function schematic shows the entiresystem equipped in accordance with Euro-pean Standard EN 746-2 (Industrial Ther-mal Process Installations).

1. Gas pressure control, measuring and safety system2. Manual valve AKT3. Solenoid valve for gas VS4. Air/gas ratio control with solenoid valve for gas GVI5. Adjusting cock V6. Bellows unit EKO7. Gas burner BIO/ZIO8. Combustion air fan9. Orifice plate with differential pressure switch DG

10. Pressure switch DG11. Pressure gauge KFM with manual cock for pressure gauge DH12. Butterfly valve for air DKL with gear motor GT13. Air flow rate control valve DK14. Bellows unit EKO15. Ignition transformer TGI and automatic

burner control unit IFS

Smelting crucible

Heating furnaceWorks photograph Messrs. Heimsoth

Bogie hearth forging furnace Works photograph Messrs. Saarstahl

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Bogie hearth furnaceMessrs. LOI Thermprocess

Directly heated heat treatment plants

Example: Annealing orforgingStructure of a heating system with low firerate lance with continuous control

Function:When the burner control unit (13) is enabled,the bypass solenoid valve of the air/gas ratiocontrol (4) opens. At the same time, the lowfire rate lance (6) is ignited via the burnercontrol unit (13).When the low fire rate lance (6) is in opera-tion, the main burner (6) can be operated viathe burner control unit (13) on request. Forthis purpose, the butterfly valve for air (7)must be in ignition position. Only then is themain gas solenoid valve (4) activated.The capacity of the main burner (6) is con-trolled by varying the butterfly position of thebutterfly valve for air (7). If heat is requested,the butterfly valve for air (7) opens stepless-ly. The increasing air pressure at the air/gasratio control (4) via the impulse line pro-duces a higher gas outlet pressure. Thismaintains the ratio between gas and air flowrate constant at all operating points. Duringentire operation, separate flame failure con-trol of the low fire rate lance (6) and of themain burner (6) is performed by the burnercontrol unit (13). The electronic flow meterDE (2) indicates the operating flow rate andthe gas quantity consumed.

1. Manual valve AKT2. Flow meter DE3. Pressure gauge KFM with manual cock for pressure gauge DH4. Air/gas ratio control with solenoid valve for gas and

bypass solenoid valve for gas GVIB5. Bellows unit EKO6. Gas burner with integrated low fire rate lance BIC..L7. Solenoid-operated butterfly valve MK with gear motor GT8. Limiting orifice9. Bellows unit EKO

10. Air pressure governor GDJ..L11. Pressure gauge KFM with

manual cock for pressure gauge DH

12. Adjusting cock GEH13. Burner control unit BCU

Roof firing systemwith BIC burners

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Directly heated heat treatment plants

Example: DryingStructure of a heating system with supple-mentary pipe and purging air orifices withcontinuous control

Function:The solenoid valve for gas (2) opens afterthe automatic burner control unit is enabled.At the same time, the ignition transformer issupplied with voltage via the automaticburner control unit, thus producing an igni-tion spark at the burner nozzle in the burner(5). The motorised butterfly valve (6) is inignition position so that the ignition air quan-tity flows to the burner (5). A proportionaloutlet pressure is produced at the air/gasratio control (3) via the impulse line. Whenheat is requested, the motorised butterflyvalve (6) opens continuously. This causes ahigher control pressure to act on the air/gasratio control (3) via the impulse line which re-sults in a higher gas outlet pressure.The maximum air flow rate is limited by theadjusting cock (7).The supplementary pipe stabilises the flameand ensures complete combustion of gasand air in the flame. The purging air orificesensure graded combustion which can in-fluence the flame temperature. This is low-ered adequately so as to prevent thermaldestruction of the components. At the sametime the burner (5) can be operated near-stoichiometrically at this operating point.The flame conduit tube protects the flameagainst cooling as the result of the materialbeing dried flowing past.

1. Manual valve AKT2. Gas solenoid valve VG3. Air/gas ratio control GIK4. Bellows unit EKO5. Gas burner BIO with supplementary pipe and purging air orifices

incorporated in flame conduit tube6. Butterfly valve for air DKL with gear motor GT7. Air adjusting cock LEH8. Bellows unit EKO

Drying furnaceWorks photograph Messrs. Solar Impianti

Age-hardening furnaceWorks photograph Messrs. Inotherm

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Continuous pusher-type furnaceWorks photograph Messrs. Ipsen

Roller hearth furnaceWorks photograph Messrs. Andernach und Bleck

Indirectly heated heat treatmentplants with recuperator burner

Example: HardeningStructure of a heating system in the jacketradiant tube with continuous control

Function:The burner control unit (12) is enabled afteran operating request from the impulse sys-tem. The solenoid valve for gas (2) and thesolenoid valve for air (8) open and the burn-er (6) is ignited by the burner control unit(12). A differential pressure is produced bythe combustion air flowing through the ori-fice plate (10). This pressure serves as thecommand variable for the variable air/gasratio control (2) which establishes a differen-tial pressure of equal magnitude betweenthe internal pulse tapping of the unit and theexternal pulse tapping. The required flowrate can be set with the flow rate adjustingcocks (3 and 9). The flue gas flow flowingback via the burner’s recuperator heats thecombustion air. The increasing temperatureof the combustion air causes an increase inpressure losses in the burner. Consequent-ly, the combustion air flow rate is reduced.The differential pressure through the air-endorifice plate (10) is reduced and the variableair/gas ratio control (2) regulates the gasflow rate proportionally to the decreasingcombustion air flow rate. This means thatthe same ratio between gas and combus-tion air is guaranteed in all operating states.

1. Manual valve AKT2. Variable air/gas ratio control with solenoid valve for gas GVRH3. Flow rate adjusting cock V4. Orifice plate5. Bellows unit EKO6. Recuperator burner ECOMAX®7. Jacket radiant tube with ceramic segmental flame tube SICAFLEX®8. Solenoid valve for air VL9. Flow rate adjusting cock V

10. Orifice plate11. Bellows unit EKO12. Burner control unit BCU 460

U-radiant tube with recuperator

Tank furnace for aluminiumWorks photograph Messrs. Inotherm

Bell-type annealing furnaceWorks photograph Messrs. LOI Thermprocess

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Important products foryour processBurners BIO, ZIO and BICBurners BIO and ZIO feature a steel tube forquarls or feature a burner supplementary pipe.Burners BIC are prepared for attachment of aceramic tube set TSC made of silicon carbide.Capacity range 1.5 to 1.000 kW, modularstructure, directly ignited and monitored, low-pollutant-emission thanks to optimised com-bustion and customised variants for variousapplications and types of gas are the out-standing features of this Series.

Ecomax®The ECOMAX® recuperator burner for directand indirect heating of industrial furnaces andthermal process installations.Maintenance-friendly design, economicaloperation, directly ignited and monitored.Capacity range 15-250 kW. Flame outlet ve-locity 120-150 m/s.Environment-friendly, low-pollutant-emissioncombustion is the characteristic feature of theECOMAX® burner. Combined in the jacket ra-diant tube with the time-proven, ceramic seg-mental flame tube SICAFLEX®. Customisedvariants and adaptation to various types of gasand mounting situations are possible.

Air/gas ratio controls GIK, GIThe air/gas ratio controls serve to maintain aconstant gas/air ratio for continuous andstepped burner control.European Standard EN 746 demands that aburner always be ignited with a stable gas/airmixture. This requirement is met with the aid ofthe air/gas ratio control.

Air/gas ratio controls and variable air/gasratio controls with solenoid valve, Modu-line systemAir/gas ratio controls GVI and GVIB for main-taining a constant gas/air ratio.Variable air/gas ratio control GVRH for main-taining a constant gas/air flow rate ratio.The modular design principle of the flow bod-ies allows compact, space-saving control sys-tems to be implemented.

Automatic burner control units IFS 258These automatic burner control units igniteand monitor gas burners in intermittent opera-tion. The fields of application relate to directlyignited gas burners of unlimited capacity (igni-tion rating ≤ 350 kW). Typical fields of applica-tion include industrial thermal process installa-tions to EN 746. Moreover, the IFS 258 unitscan also be used on atmospheric burners.Functions: Flame failure control with ionisationsensor or with UV sensor, ignition and moni-toring possible with one electrode, steplessswitch-off sensitivity adjustable for the flamecurrent, test socket for no-break flame currentcheck, switchable from restart to immediatefault lock-out following flame failure, and withsignalling contacts for operation and fault.

Burner control units BCUAutomatic burner control unit and ignitiontransformer in a compact metal casing takethe place of the local control cabinet, for di-rectly ignited burner or pilot and main burner.For continuous operation with ionisation con-trol, for intermittent operation with UV controland manual operation for burner adjustmentand for diagnosis. BCU..L with air valve con-trol, including pre-purging.The program status, the unit parameters orthe flame signal can be tracked on a 7-seg-ment display. Moreover, the BCU can beconnected via an optical interface to a PC inorder, for instance, to record the flame signalover a long period or in order to modify para-meters of the BCU.

Kromschröder iscommitted to

producing highquality and to

being a supplier ofleading-edge

technology.

We atKromschröder

understand that thequality of our

products mustconform with the

properties andfeatures of marketstandards and our

customers’expectations.

Aims:Kromschröder

wishes to consolidateits good market

position in the metal-working industry.

Competence in gasGas is considered to be one of the most im-portant energy resources in today’s - andparticularly tomorrow’s - world.Kromschröder is a leading manufacturer oftop products and systems for measurementand control of gases, for automation ofindustrial furnaces and for control of heattreatment processes.Through innovative research and develop-ment of trendsetting design, Kromschröderis a regular source of new impetus for this in-teresting market.Modern production methods and staff-orien-tated production have made Kromschrödera competent partner.

QualityKromschröder’s quality policy is based on aglobally acclaimed system for ensuringproducts and services of consistently highquality.Certification in compliance with StandardDIN EN ISO 9001 confirms the efficiency ofour system.We are well aware, however, that a qualitysystem is not enough on its own. It is onlywith the active support of our staff that we areable to keep our ears close to the ground inthe market to enable us to respond quicklyto our customers’ needs. With the strategy ofsteady, continuous improvement of all theprocesses involved in the creation and dis-tribution of our products, wewant to actively implement therequirements and expecta-tions raised by the marketbecause customer satis-faction is the standardwe strive to achieve.

Environmental protectionProtection of the environment is a de-clared company aim at Kromschröder: Ahealthy company with a healthy workingclimate in a healthy environment. And withthis, we also associate high product qual-ity expected by today’s customers.The experience and successes of thepast ten years have shown that the pathleading to this objective needs to be re-formulated time and time again. We havelearnt a great deal and also achieved agreat deal, as shown by our annual, up-dated environment report.Not least, pursuing great aims also ne-cessitates having reliable partners to ac-company us: Reliable staff, time-provenproduction and distribution partners and,above all, convinced customers. For ourcustomers, natural gas is the economicaland environment-friendly energy source.

Inspection and certification worldwideApproval or certification in accordancewith applicable national or internationalstandards and specifications is a matter ofcourse with safety equipment and sys-tems.By participating in relevant internationalbodies and standards committees, we atKromschröder ensure that our customers’interests are represented in internationalstandardisation activities.

We want to use themost moderntechnologies andtreat our environ-ment with all duerespect

Our customers aresatisfied if we meettheir requirementsand satisfy theirexpectations of our products.

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R

-DVGW-Reg

Administration and production in Lotte (Büren) Group workstation