13 3/8" Hydraulic two-stage collars/Double stage collar/9 5/8" L80 Mechanical two-stage collar for cementing
Use:
Hydraulic Stage Cementer features inner closing structure, opening through pressure 
difference. The closing plug drives the closing sleeve down and then shut circulation 
ports.
Features:
1. Opening pressure can be adjusted and it is not subjective to hole angle.
2. The pressure-relief design prevents fluid trapping and compression during the closing phase of the tool's operation.
3. The I.D of upper/lower sub is the same as that of casing, but smaller than that of closing sleeve, which can minimize chances of damages to the closing sleeve.
4. The inner seats are made of an easily drillable butyronitrile rubber / aluminum material. Both the opening and closing seats lock against rotation for easy drill-out.
Technical Parameters: