其中为了保证坐封球可以在“check valve”中移动。“上打捞头”

其中为了保证坐封球可以在“check valve”中移动。“上打捞头”中放坐封球的腔体的直径应比坐封球稍大一些，从而可以保证坐封球在其中可以正常移动。由于本次设计中坐封球的尺寸为44.5mm，最终确定的“上打捞头”和坐封球配合的尺寸为44.6mm。其中由于球座设计的结构如图1.3所示：

In order to ensure that the setting ball can move in "check valve". The diameter of the cavity where the setting ball is placed in the "upper fishing head" shall be slightly larger than that of the setting ball, so as to ensure that the setting ball can move normally. Since the size of the setting ball in this design is 44.5mm, the final matching size of the "upper fishing head" and the setting ball is 44.6mm. The structure of ball socket design is shown in Figure 1.3:

In order to ensure that the setting ball can move in "check valve". The diameter of the cavity where the setting ball is placed in the "upper fishing head" should be slightly larger than that of the setting ball, so as to ensure that the setting ball can move normally in it. As the size of the setting ball in this design is 44.5mm, the finally determined size of the "upper fishing head" and the setting ball is 44.6 mm. Among them, as the structure of the tee design is shown in Figure 1.3: