The pipe blank dimensions and the necking force were calculated. The structure of neckingdie for the flame pipe was introduced.
确定了缩口次数并计算了管坯尺寸和缩口力。
2
According the structure characteristics of oil filling pipe, combining production experience, designed expanding and neckingdie.
针对加油管的结构特点，结合企业生产经验，给出了连续扩。
3
The paper has described the neckingdie structure and the forming process for shell bodies. If the neckingdie was changed, two necking process can be finished with a set of die.