毕业设计外文翻译 关于液压机期刊

关于液压机期刊

MetalScienceandHeatTreatmentVol.43,Nos.5–6,2001

UDC669.14.018.298:621.226

STEELFORCRAMPSOFHYDRAULICPRESSCRADLES

I.A.Borisov1

TranslatedfromMetallovedenieiTermicheskayaObrabotkaMetallov,No.5,pp.24–26,May,2001.

INTRODUCTION

Creationofinstallationswithahighunitpowerisac-companiedbygrowthoftheirsizesandthemassoftheprin-cipalparts.Thisraisestherequirementstothesteelsusedfortheproductionofheavy-dutypartsforsuchinstallations.

Inthepresentworkwesolvedtheproblemofthechoiceofsteelformakinglarge-sizeweldedcradlecrampsthatarehighlyloadedcomponentsofhydraulicpressesandcande-velop,forexample,aforceof650MN.

Thedesignofacradleincludestwentyweldedcramps.Thelengthofeachcrampis30m,thewidthis1.5–4m,andthethicknessis0.28–0.32m.Acrampweighs160tons.Itshouldbenotedthatthemaximumthicknessofthesheetsusedforfabricatingsuchcrampsis0.36mwiththeprocessallowance.

Basedonthedatacontainedinnativehandbooksofsteelgradesandspecialspecifications[1–3]andtheexperienceofplantsproducingrolledsheets,weanalyzed10carbonandlow-alloysteels,namely,25,30,16GS,20GS,25GS,09G2S,22K,20Kh2MA,ITs-14,and16GNMA.ItturnedoutthatonlygradesITs-14and16GNMAofthelistfullysatisfytherequirementsofthespecifications.Wedidnotknowofanyexperienceoftheirusefortheproductionofpartswithathicknessof0.36m.Steel30usedforplatesupto0.5mthickwastheonlyexception,sinceitmettherequirementsoftheTUwithrespecttothelevelofmechanicalproperties.

SteelsITs-14and16GNMAhaveaquitehighadaptabi-litytomanufactureandarewidelyusedintheindustryfor

1

theproductionofrolledsheetspossessingahighstrengthandductilityandatwice-higherimpacttoughnessthanisre-quiredbytheTU.Thesteelsaresatisfactorilyweldableinlargecrosssections.

Takingthesepropertiesintoaccountwechosesteel16GNMAusedforfabricatingboilerdrumswithhighsteamparametersasaprototypeforourstudy.METHODSOFSTUDY

Thespecifiedmechanicalpropertiesofcrampsteelsareasfollows:s0.2³225MPa,sr³450MPa,d³18%,KCU³0.4MJ/m2.

Thechemicalcompositionofsteel16GNMAwascor-rectedfortheproductionofplateswithrespecttothemainalloyingelements.Inparticular,thelowercarbonlimitwaswidenedby0.1%,thecontentofmanganesewasdiminishedby0.1%,andmodificationwithvanadiumandtitanium(0.05%Tiand0.07%V)wasundertakeninordertopreservethestrength.Thesechangesweredirectedatimprovingthefabricabilityofthesteelandobtainingasteadylevelofitsmechanicalproperties.Asaresult,thesteelhasbecomepo-pularintheproductionofpowercomponentsofheavyhy-draulicpressesunderthenameofITs-1M.

Wealsotriedsteel30Aasthesimplestandeconomicallyexpedientvariant(Table1).

Theteststeelsweremoltenin100-tonopen-hearthfur-nacesbythescrapprocessandcastinto68-and82-tonmolds.Theingotswereforgedwithandwithoutpreliminaryupsetting.Theforgedplatesweresubjectedtoasinglean-nealing(withfullrecrystallization)at860°C(steel30A)and

TsNIITMAShResearchandProductionAssociation,Moscow,Russia.

TABLE1.ChemicalCompositionoftheStudiedSteels

Contentofalloyingelements,%

Steel

C

Si

Mn

Ni

Mo

Cr

Ni

Contentofadmixtures,%

Cuatmost

S

P

30AITs-1M0.26–0.320.17–0.370.50–0.800.12–0.180.17–0.370.70–1.00–1.0–1.3–

0.45–0.55–0.300.25–0.250.300.0200.0200.0200.020

199

0026-0673/01/0506-0199$25.00©2001PlenumPublishingCorporation

第1页下一页