连(Lian)铸(Zhu)生(Sheng)产(Chan)中(Zhong),(?)用(Yong)来(Lai)钢(Gang)包(Bao)滑(Hua)动(Dong)机(Ji)构(Gou)滑(Hua)动(Dong)的(De)耐(Nai)火(Huo)材(Cai)料(Liao)部(Bu)分(Fen)。(?)成(Cheng)分(Fen)一(Yi)般(Ban)为(Wei)镁(Mei)碳(Tan)结(Jie)构(Gou),(?)表(Biao)面(Mian)涂(Tu)有(You)铅(Qian)粉(Fen),(?)以(Yi)保(Bao)持(Chi)滑(Hua)动(Dong)的(De)流(Liu)畅(Chang)性(Xing)。(?)中(Zhong)间(Jian)有(You)开(Kai)口(Kou),(?)并(Bing)根(Gen)据(Ju)开(Kai)口(Kou)直(Zhi)径(Jing)大(Da)小(Xiao)和(He)机(Ji)构(Gou)样(Yang)式(Shi)命(Ming)名(Ming),(?)如(Ru)C10,C30,B40,B60.