什么是斜刃口冲裁?
参考答案:
斜刃口冲裁是降低冲裁力的一种方法。就是将模刃口制成相对坯料成一定角度的倾斜,这样冲裁时模具刃口与坯料的接触是渐进的,使得载荷均匀且平稳。
读短文,选择答案。
Li Ming, Jenny and Danny are good friends. They all like to draw. They are drawing now. Li Ming draws
three red apples. Jenny draws four yellow oranges. Danny draws one blue pencil.
1. Li Ming draws three __________ apples.[ ]
A. blue
B. green
C. red
2. Danny draws __________ blue pencil.[ ]
A. one
B. two
C. three
3. Li Ming, Jenny and Danny are good __________.[ ]
A. boys
B. girls
C. friends
4. They are ____________ now.[ ]
A. singing
B. playing
C. drawing
手摇压缩机齿轮油泵打不上压,对压缩机运行无影响,作开机处理。