During the course of production, conditions may change, either due to the reservoir pressure being reduced to a point that it cannot flow naturally or the souring of production fluid in the field. Christmas trees may not be suitable for the well’s current condition. A new Christmas tree could be installed on a sour field or removed due to artificial lifting requirements.
Example 1: For wells that no longer produce naturally and require artificial lift, Cameron could remove the production tree and install the artificial lift equipment in its place. The original Christmas tree would be returned to Cameron, and a service fee would be applied to get the returned equipment back to working condition. The equipment then would be stored, ready for installation on a new well that flows naturally.
Example 2: The Christmas tree could be changed out from the production choke to the top of the tubing spool. Another option might be to change out the equipment from the Christmas tree and production choke and leave the tubing hanger and spool in place, as they may have been rated to meet more aggressive service conditions. For a 20- to 30-well large-bore completion, Cameron and the operator might agree to manufacture and produce 10 Christmas trees to the new specifications for purchase. Cameron could then remanufacture or upgrade the returned equipment from the first 10 wells to enable the operator to replace all of the Christmas trees on a predetermined workover schedule.
This could result in minimizing lost production and intervention, and reducing hazard exposure and lead time. It also could mean a possible reduction of total equipment cost based on refurbished equipment versus new. The remaining 10 trees that were removed from the well could be remanufactured to new specs and held as customer property for the next project. Stringent acceptance criteria then would be set for the used equipment.
Various options for refurbishment exist, some taking into consideration whether certain individual components are rated for more aggressive service conditions. The operator and Cameron professionals would determine the advantages of these options. Implementation of exchange options could:
- Decrease lost production
- Minimize intervention
- Reduce hazard exposure
- Cut lead time
- Lower total equipment cost based on refurbished versus new equipment
- Manage assets from one location to the next
- Reduce the amount of customer property