校对环规

校对环规
    校对环规是机械制造业中内孔尺寸传递的基准环规，可用于气动内径侧头，机械量表的基准件。
相关参数：
    公称直径                    制造偏差                       圆 度                      素线平行
＞φ3～10                         ±1.0                              0.5                            1.0
＞φ10～30                       ±1.5                              0.5                            1.0
＞φ30～80                       ±2.0                              0.8                            1.5
＞φ80～120                     ±2.0                              1.0                             2.0
＞φ120～180                   ±2.5                              1.0                             2.0
＞φ180～250                   ±3.5                              1.2                             2.5