retrievable packer造句怎么写

4、It is attached to the bottom end of a retrievable packer, and opens and closes automatically with the change of the pressure of the hot fluid column in the tubing-casing annulus.

2、cup type retrievable packer

1、single string retrievable packer

3、In the design of the hydraulic dual-anchor retrievable packer, the following should be taken into consideration: (1)selection of anchoring mode;