Metal Carrier Replacement Via Polypropylene & EPDM Reduces ...

Productsfor yoursuccessMetal Carrier Replacement Via Polypropylene & EPDMReduces Costs in Automobile Sealing Profiles

Metal Carrier Replacement Via Polypropylene & EPDMReduces Costs in Automobile Sealing ProfilesToday, motor vehicle seals that are applied to thebodywork need to satisfy many different functions. Inaddition to their sealing effect, it is above all the dynamicproperties of the seal as well its resistance to weatheringand different temperatures that need to be taken intoaccount. Apart from the technical properties of theproduct, further factors such as recyclability, weight andmanufacturing are becoming increasingly important. Forthis reason, the substitution for metal inmany fi elds of automotive engineeringis making ever greater advances.The structure of the fabricated reinforcement with itsalternating arrangement of hard and soft segmentsis similar to that of a spine. In common with thespine, the new process allows for maximum possiblestrength at minimal weight in conjunction with excellentlongitudinal fl exibility. The U-shaped segments of thehard components provide the required high degree ofclamping force, while the soft components – similarThe use of high-grade engineeringplastics as a construction material inplace of metal has enabled the fueleconomy as well as the reliability ofmodern motor vehicles to be raisedsubstantially. That’s why TROESTERGmbH & Co. KG has recently offeredan extrusion process which allowsthe flexible metal carrier in dynamicbodywork seals to be replaced ina simple manner by an engineeringplastic. In this patented manufacturingprocess, a fl exible U-shaped reinforcement is fabricatedin the extruder head by means of sequential co-extrusionand integrated with all of the other functional componentsof the seal in a single step.to an invertebral disc – endow the reinforcement withoutstanding fl exibility. In addition to the costs of themetal carrier and its susceptibility to corrosion, the newprocess also dispenses with all of the metal strip handlingprocesses in the form of storage and bending devices.There is a choice of various material combinations for thenew reinforcement, depending on whether the customeris more focused on cost savings and cost effectiveness,or instead opts for weight reduction and a greatersuitability for recycling.

The use of highly-fi lled polypropylene in combinationwith an EPDM soft profi le compound will provide themaximum cost-effectiveness in the new process.Without any major changes to the normal course ofEPDM processing, this will already result in material costsavings of over 20 % compared to a conventional EPDMprofi le with metal reinforcement. The necessary thermalseparation of materials in the extruder head can takeplace in quite different ways and is already integratedin the sequential head. Present-day vulcanisationequipment continues to be employed in its customarymanner in the new process. The early introductionof microwave energy into the profi le serves to ensurethe dimensional stability of the profi le cross-sectionin subsequent processing steps. Even without metalreinforcement, the vulcanised proportion of rubbergives the profi le suffi cient strength to be able to passthrough all of the downstream processing steps withoutsuffering deformation. At the normal production speedof around 20 m/min, spray cooling is used to cool thefi nished profi le after it has undergone vulcanisation.During the course of this, the fi nal cross-section shape,especially the position of the U-shaped clamping foot,is determined by mechanically-controlled cooling of thepolypropylene section at the end of the line.the mechanically-controlled cooling of the profi le, as iscustomary during calibration, takes place immediatelyafter the extruder head and not, as is the case forEPDM, at the end of the line. There are howeverdisadvantages here compared to EPDM with regardto productivity, as the TPE profi le neither has tensilestrength nor dimensional stability immediately onexiting the die. Consequently, the maximum possibleline speed is restricted to approx. 12 m/min for thismaterial combination. The material costs for a TPEpolypropylenesolution are also higher than those forEPDM-polypropylene, but this can be partially offsetsince the line equipment will be simpler, as vulcanisationtechnology is no longer necessary.Working in conjunction with a well known profi lemanufacturer, complete seals will be produced asevaluation samples until the end of 2010 and then testedon vehicles from mid 2011. For further information andadvice on the subject of metal carrier replacement inautomobile sealing profi les, interested customers shouldcontact the sales department of the Engineering RubberProducts division at TROESTER GmbH & Co. KG.If, on the other hand, the focus is on recycling and areduction of weight, then a material combination ofpolypropylene and thermoplastic elastomers (TPE) ispreferable. Where TPE and polypropylene is used inplace of EPDM and metal, a weight reduction of over35 % in respect of the complete seal is easily possible.Because of their similar processing temperatures,thermal separation in the extruder head is notnecessary for this material combination. In addition,

TROESTER GmbH & Co. KGAm Brabrinke 1-430519 Hannover, GERMANYPhone +49-511-87040Fax +49-511-864028E-mail innovations@troester.dewww.troester.deTROESTER Machinery, Ltd.300 Loomis AvenueCuyahoga Falls, Ohio 44221, USAPhone +1-330-928-7790Fax +1-330-928-7239E-mail info@troester-usa.comwww.troester-usa.comMachines and complete lines built by TROESTER are known all over the worldand are synonymous with technological advancement, quality and outstandingperformance in the fi elds of rubber and cable processing.TROESTER Machinery(Shanghai) Co., Ltd.Workshop No. 1, Area CNo. 6999 Chuan’sha Road, PudongShanghai 201202, PR CHINAPhone +86-21-58598308Fax +86-21-58598310E-mail info@troester.cnwww.troester.cnTROESTER Moscow50, Zemlyanoy Val,Room No. 1102 GIAPMoscow, 109815, RUSSIAPhone & Fax +7-495-9166093E-mail lusia137@rol.ruInnovations for the Rubber IndustryFür etwaige Garantien oder Gewährleistungs verpflichtungenist ausschließlich der Vertrag zwischenKunden und TROESTER maßgebend. Die hier gemachtenAngaben stellen keinerlei Zusicherungen irgendwelcherbesonderer Eigenschaften dar, sie dienen lediglichder allgemeinen Information und können im Einzelfallabweichen. Ansprüche irgendwelcher Art können hierausnicht abgeleitet werden. Die Beachtung gewerblicherSchutzrechte ist in jedem Fall Sache des Kunden.Only the contract between the customer and TROESTERis binding for any guarantees and commitments. Theparticulars given herein do not represent promises ofany special characteristics. They serve purely for generalinformation pur poses and may differ in individual cases.No claims of any nature may be derived herefrom. Theobservation of commercial trade marks or patents shallin every instance be the responsibility of the customer.2010/10 · ERother, van Cleef. Design & Kommunikation