文档介绍：有关机械的英语论文 Rises 冒口? Rises are designed and placed so as to ensure filling the cavity during solidification. ?冒口的设计及放置等,以确保加油站腔凝固过程。? They also art to relieve gas pressure in the mold and to reduce pressure on the lifting surfaces of the mold . ?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。?? The volume of metal in the riser should be sufficient to retain heat long enough to feed the shrinkage ? cavity and equalize the temperature in the mold ,avoiding ? casting strains . ?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。? The riser requirements vary with the type of metal being poured. ?该冒口要求都会有所不同,同类型的金属被浇。? Gray case iron , for example, needs less feeding than some alloys because a period of graphieization occures during the final stages of solidification which ? causes an expansion that tends to counteract the metal ? shrinlege. ?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? Many nonferrous metals requires elaborate feeding that tends to counteract the casting . ?许多有色金属的要求阐述喂养趋于抗衡铸造。? Two riser designs for the same casting are shown in --4 ?两个冒口设计,同时铸造示于图 7--4 。? Rises are placed near th