Testing and Optimization

Into the future with the right climate.As professionals in the sector of controls,the EGELHOF group has developed andproduced expansion valves and controlelements for refrigeration and heat tech-nology according to the highest technicalquality requirements since 1938.

All famous producers worldwide withinthe automotive and heat industry useEGELHOF products.

All EGELHOF activities are based on avision of the future, a tradition of compe-tence and a high degree of willingness toinvest.

The EGELHOF Group

At the company’s core - the production -modern production lines, their own toolshop and machine building make forgreat flexibility mean meeting clients’needs in a timely manner.

About 500 competent and experiencedEGELHOF staff members from Develop-ment, Design, QA, Production and Salesguarantee optimum production flowsand a consistently high series-produc-tion quality.

Modern production plants in Europe,the USA and Asia not only assure theirown competitiveness, but that of allEGELHOF clients.

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Manufacturing in the Sixties

Company

individual components have a growingimpact on each other; hence optimizati-on of a single component does notalways result in a system enhancement.

EGELHOF has therefore decided tomerge its experience as a controlvalves producer with the experienceof EGELHOF clients.

Systematic Testing

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Increasing Standards withregard to the EnvironmentIncreasing requirements so as to reducedirect CO2 emissions from vehicles canbe directly fulfilled by optimizing drivesystems. Increasing the efficiency of auxiliaryequipment means other indirect decisiveenhancements as well.

A vehicle’s A/C system offers a widefield for optimization, however for theuser’s comfort, refrigeration capacityought to be at least maintained, and asfor circuits with two evaporators it oughtto even be increased.

In addition to the discussion regardingdirect CO2 emissions, we are faced withthe legal requirement to replace therefrigerant and greenhouse gas R134awith alternative refrigerants. This basi-cally requires an adaptation or even thedesign of a completely new refrigerationcircuit for the A/C system. While doingso, our target is to increase efficiencyand to reduce the weight of the systemand of charge quantity. The functions of

EGELHOF A/C System Test Bench

As a special service, EGELHOF offersclients and partners the calibration ofA/C systems with one or two evapora-tors at its own A/C system test bench.

In cooperation with clients and partners,a complete A/C system design can becarried out.Refrigeration circuit components andtubes are installed as close as possibleto their original assembly position, i.e. inthe same way they are installed in thevehicle.

adapt and validate the selection in respect of thermostaticexpansion valves (TXV) within system development for andin cooperation with clients

metrological support with regard to further developmentof A/C systems with one or two evaporators operatedwith R134a

metrological support with regard to new developments ofA/C systems operated with R744 (CO2) or alternative refrig-erants

metrological support with regard to the development andoptimization of systems with an internal heat exchanger

analysis so as to find weak points within refrigeration circuits

benchmarking of various circuit components

simulate or reproduce errors occurring in the fieldand development of corrective actions

examine heat exchangers within the systemin respect of air diffusion and oil transport

examine condensation and condensation discharge

evaluate capacity / performance of an A/C systemrelated to refrigeration circuit

Main focus of tests carried out on the system test bench:

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Climate ChoiceLarge-scale operating ranges allow forthe simulation of nearly all applicableclimate conditions.

Climate, Performance and Data

Climate Simulation

Utilizable inside dimensions of test bench: (l x w x h) 7.75 m x 2.75 m x 2.75 mThe internal space is divided by a movable dividing wall into two zonesthus enabling adaptation to different versions of test circuits.

Maximum refrigeration capacity (test object): 18 kW, including up to 8 kW in case of a rear A/C system

Maximum condenser capacity (test object): 27 kW

Total temperature range of front -5°C to 60°Cand rear system:

Controlled humidity range: 10% to 90 % of rel. humidity

Uncontrolled humidity range: up to -10 °C dew point (dry)

Total temperature range 5°C to 65°Cof condenser:

Compressor rpm, 500 to 10,000 rpm drive via electrical motor:

Torque on compressor (0-3,000 rpm) min. 40 Nm

Oil concentration in R134a test circuits is continuously measured.Refrigerant mass flow is measured according to Coriolis principle, 2 sensors are applied.

Capacity/Performance key figures of EGELHOF A/C system test bench:

Standard range

Extreme range 3

Extreme range 1Extreme range 2

Everything is consideredControl functions are realized by graphicuser interfaces of the InTouch®-Software.Priority has been given to simple opera-tion and clarity.Instrumentation data are transferred viaSimatic Control made by Siemens andProfibus with a measurement range ofup to 1Hz of the Kohlenberg MSR32software.Approximately 150 measuring channelsand up to 200 computational channelsincluding relative formula are currentlyapplied.The computation base for data aroundthe refrigeration circuit is the chemicalmedia data software REFLIB linked tothe MSR32 of ILK Dresden.During a test run, a log p,h-diagramcan be displayed online to follow up thecircuit process.

Total Control

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Instrumentation and Control

Testing circuit channel assignmentEverything done automatically

Safe and sure resultsComplete program-controlled measuringruns are carried out; if required, an opti-mum utilization of test bench runningperiods is possible.

Each measuring task is handled in theform of a project. By doing so, settingsof measuring and computational chan-nels, channel groups, program controldata, and protocol data are saved. Theymay therefore be loaded again at a laterdate.

Measuring data are saved in MSR32format and can be converted into ASCIItext, in EXCEL® - or in DasyLab® for-mat.For further evaluation, EGELHOF canmake all of the project and measuringdata on a data carrier (CD-ROM) availa-ble to the customer.

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Instrumentation and Control

We are ready to meet your demandsEGELHOF offers its A/C system testbench as well as other test equipmentfor carrying out external tests, i.e.the helium leakage test system forcarrying out leakage tests and the saltspray fog chamber according to DIN ENISO 9227.

Testing is our Business

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Helium leakage test system for carryingout leakage tests:Stricter environmental requirementswith regard to emissions levels andlonger maintenance intervals require thatsystems are no longer leaky.In particular, new A/C systems forvehicles applying CO2 as a refrigerantmake leak tightness a prerequisitesince high internal pressures up to 130bar are reached.

Test pressures up to 200 bar can be setin the automated EGELHOF heliumleakage test system. Parts charged withinternal pressure as well as parts pre-charged with helium can be tested byapplying integral or sniffer probe mode.

Other EGELHOF Test Equipment

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EGELHOF Test Equipment

Corrosion test in salt spray fog:The EC guideline concerning oldvehicles which requires the use ofchrom-6+-free corrosion protectivecoatings has resulted in new coatingmaterials and coating processes. Inmany products a variety of differentmaterials are combined. Consequently,the coaction of different metallic materi-als can result in a saliferous, humid envi-ronment causing considerable corrosion.In order to guarantee the longevity ofcomponents, EGELHOF carries outextensive tests for each new materialcombination and in connection withcustomer validations in their own saltspray fog chamber according to DIN ENISO 9227.

In addition to test equipment (also offeredas an external service), during productdesign, all EGELHOF products are sub-mitted to additional high-quality simula-tions and test benches in their ownTesting Department:

Environmental simulation of heatand cold with and without influenceof humidity:Even the most extreme external tempe-rature influences on EGELHOF productsmust not change guaranteed features.To assure this, several computer control-led climate chambers and temperatureovens, as well as a temperature shockchamber, are available to the TestingDepartment.

Temperature range from -70°C to +250°C

Humidity range from 10% to 98% ofrelative humidity

Simulation of endurance:Operation reliability of EGELHOF pro-ducts during their long life is ensured byapplying load alternation tests.In pressure test benches, life up to wearis found in time lapse.

Components test benches:Valves´ dynamic behavior can only beanalyzed in a real refrigeration circuit.Precisely defined operating conditionsallow for the testing and optimization ofopening characteristics, oscillationbehavior and performance.

Due to the fact that passengercompartments are becoming moreand more quiet, the development oflow noise A/C systems is becomingincreasingly important.

By applying an acoustical measuringsystem, EGELHOF can detect flownoises and structure-borne noises onprototypes. This kind of informationenables EGELHOF designers to continu-ously minimize the existence of distur-bing noise emissions.

EGELHOF products: put to the acid test

The competent EGELHOF team will be happy to assist youin carrying out your measuring tasks.

Please send your inquiries to the following address:

OTTO EGELHOF GmbH & Co. KGStuttgarter Strasse 60

D - 70736 Fellbach+49 (0)711/575 47 0

e-mail: testing@egelhof.comInternet: www.egelhof.com

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