1. Features
■ Flow direction is from the bottom to the top of the sand control screen.
■ Flow regime becomes a single phase laminar flow after the gravel solids enter the annular between the tubing and casing..
■ There is no gravel settling at front edge and tail of gravel slurry, so that the gravel slurry easily pass the perforation .
■ Gravels move from the bottom to the top and gravel slurry can be fully dehydrated in the screen section, which results in solid pack...
■ Replacement of slurry and packing are performed in the same trip.

2. Technical principle
Utilizing cementing principle, the gravel slurry enters from the bottom of the sand control screen to the external annular, to realize squeezed gravel packing and ceaselessly circulated gravel slurry to the annular between the screen and casing (or screen and formation).

3. Solutions to
■ Sand bridge due to multi-layer packing and highly-deviated well
■ Gravels sand crack due to squeeze packing
■ Continuity and integrity of formation, perforation and gravel packing in the annular between the screen and casing.

4. Application.
It has been used in over 20 wells with great success.