有关机械的英语论文.ppt

有关机械的英语论文Rises

冒口Risesaredesignedandplacedsoastoensurefillingthecavityduringsolidification.冒口的设计及放置等，以确保加油站腔凝固过程。Theyalsoarttorelievegaspressureinthemoldandtoreducepressureontheliftingsurfacesofthemold.他们还采取行动，以纾缓气体压力，在模具，并减少压力解除表面的霉菌。Thevolumeofmetalintherisershouldbesufficienttoretainheatlongenoughtofeedtheshrinkagecavityandequalizethetemperatureinthemold,avoidingcastingstrains.体积的金属在冒口应足以保持热量，只要够养活缩口和平衡温度的模具，避免铸造株。Theriserrequirementsvarywiththetypeofmetalbeingpoured.该冒口要求都会有所不同，同类型的金属被浇。Graycaseiron,forexample,needslessfeedingthansomealloysbecauseaperiodofgraphieizationoccuresduringthefinalstagesofsolidificationwhichcausesanexpansionthattendstocounteractthemetalshrinlege.灰铸铁，例如，需求不足喂养比一些合金的，因为一个时期的石墨化过程中发生的最后阶段的凝固，引起群众的扩展趋于抵消金属的收缩Manynonferrousmetalsrequireselaboratefeedingthattendstocounteractthecasting.许多有色金属的要求阐述喂养趋于抗衡铸造。TworiserdesignsforthesamecastingareshowninFig.7--4两个冒口设计，同时铸造示于图7--4。Risesareplacedneartheheavysectionsofthecasting.冒口放在附近重型路段铸件。Thefeedmetalmustbelocatedabovethehighestpointofthecasting.饲料中的金属必须设以上的最高点，该点的铸件。ChillBlocks

冷块Chillblocksaremetalblocksplacedinthemoldforlocaalizedheatdissipation.冷块金属块放置在模具局部散热。Theymaybeplacedataninterscationorjointwherethereisacomparativelylargevolumeofmetaltocool,thusrelievingahotspotormaintainingamoreuniformcoolingrateandbettermicrost