RB2 Standing Valve
To retain a column of fluid in tubing string.
The BT RB2 Standing Valve consists of nine components:
1. Fishneck2. Equalizing Sleeve3. Ball Seat4. Bypass Mandrel5. Packing Mandrel6. Packing Nut7. Ball8. Male Back Up Ring9. Female Back Up Ring
The BT RB2 is generally placed in the tubing string when there is a need to retain fluid from being reabsorbed back into the wellbore formation.
A good example if this would be above a submersible pump.