FABUSHIJIAN：2018-12-12 16:44:00 FANGWEN：2120
一、阀门毛坯的选择原则
JIXIEJIAGONGCHANGYONGDEMAOPIYOUZHUJIAN、DUANJIAN、XINGCAIJIHANJIEJIAN。BUTONGDEMAOPIZHONGLEIYIJIMAOPIDEJINGDU、CUCAODUHEYINGDUDENGDUIJIXIEJIAGONGGONGYIGUOCHENGYOUZHEZHIJIEDEYINGXIANG。
XUANZEFAMENMAOPISHIYINGKAOLVRUXIADEYIXIEYINSU。
①LINGJIANDECAILIAOJIDUICAILIAODEZUZHIHEXINGNENGYAOQIU。SHEJITUSHANGGUIDINGDELINGJIANCAILIAO，DATISHANGJIUJUEDINGMAOPIDEZHONGLEI。LIRU，LINGJIANCAILIAOWEIZHUTIEJIUBIXUYONGZHUZAOFANGFALAIZHIZAOMAOPI。DUIYUGANGZHILINGJIAN，ZAIXUANZEMAOPISHIYINGKAOLVDUICAILIAODELIXUEXINGNENGYAOQIU。LIRU，ZHIZAOGAOYAFAMENDELINGJIANYIBANYINGJINLIANGXUANYONGDUANJIANHUOHANJIEJIAN，YIBAOZHENGCAILIAOJUYOULIANGHAODELIXUEXINGNENG。
②LINGJIANDEJIEGOUXINGZHUANGHEWAIXINGCHICUN。LINGJIANDEJIEGOUXINGZHUANGSHIYINGXIANGMAOPIXUANZEDEZHONGYAOYINSU，LIRU，JIEGOUXINGZHUANGFUZADEFATIKEXUANYONGZHUJIAN。CHICUNDADEFATIKEXUANYONGSHAXINGZHUZAO;CHICUNXIAODEZECAIYONGRONGMOZHUZAO。
③SHENGCHANGANGLINGDEDAXIAO。LINGJIANDESHENGCHANGANGLINGYUDA，CAIYONGGAOJINGDUHEGAOXIAOLVDEMAOPIZHIZAOFANGFAJINGJIXIAOGUOYUHAO。
④MAOPIZHIZAODETIAOJIAN。YINGGENJUXIANCHANGDESHEBEIZHUANGKUANGHEGONGYISHUIPINGLAIXUANZEMAOPI，BINGKAOLVDAOFAZHANQIANJING，ERZHUBUCAIYONGXIANJINDEMAOPIZHIZAOFANGFA。
毛坯及机械加工余量
一、加工余量及其确定方法
(YI)JIBENGAINIAN
1.JIAGONGZONGYULIANGHEGONGXUYULIANG
（1)JIAGONGZONGYULIANGMAOPICHICUNYULINGJIANTUDESHEJICHICUNZHICHA。
（2)GONGXUYULIANGXIANGLINLIANGGONGXUDECHICUNZHICHA·
（3)JIBENYULIANGMAOPIJIBENCHICUNYULINGJIANTUSHANGXIANGYINGDEJIBENCHICUNZHICHA，XIANGLINLIANGGONGXUDEJIBENCHICUNZHICHA，FENBIECHENGWEIJIBENJIAGONGZONGYULIANG(}boj)YUJIBENGONGXUYULIANG(Zbj}a
（4)JIAGONGZONGYULIANGYUGONGXUYULIANGDEGUANXI
SHIZHONGn——GONGXUHUOGONGBUSHUMU。
2.DANMIANYULIANGYUSHUANGMIANYULIANG
（1)DUIYUHUIZHUANBIAOMIANJIAGONGDANMIANYULIANGXIZHIXIANGLINLIANGGONGXUDEBANJINGCHA，SHUANGMIANYULIANGXIZHIXIANGLINLIANGGONGXUDEZHIJINGCHA，YI:zb.2zb。BIAOSHI。YIBANDUOCAIYONGSHUANGMIAN(ZHIJING)YULIANG。HUIZHUANBIAOMIANJIAGONGYULIANGRUTU8YI2YI1SUOSHI。
DUIYUWAIYUANBIAOMIAN
对于内孔表面
SHIZHONGda . Da_SHANGGONGXUZHIJINGCHICUN;
db . Db—BENGONGXUZHIJINGCHICUN。
(2}DUIYUPINGMIANJIAGONGDANMIANYULIANGXIZHIYIYIGEBIAOMIANWEIJIZHUNJIAGONGLINGYIGEBIAOMIANSHIXIANGLINLIANGGONGXUDECHICUNCHA。SHUANGMIANYULIANGXIZHIYIJIAGONGBIAOMIANDEDUICHENGPINGMIANWEIJIZHUNTONGSHIJIAGONGLIANGBIAOMIANSHIXIANGLINLIANGGONGXUDECHICUNCHA
DUIYUWAIBIAOMIANDANMIANYULIANG:zb=a-b
SHUANGMIANYULIANG2Zb=aYIb
