Overshot Seal Pup
In some cases, wells may require repairs to existing packers or hangers that have lost their sealing capabilities. Other wells may require casing to be chemically or mechanically cut to remove existing equipment and require installation of new equipment. Core design’s Carrot Patch tool can be used when loss of internal diameter is not a concern. When internal diameters is required to go unchanged, the Overshot Seal Pup (OSP) can be used.
The OSP contains a mule shoe nose at the bottom and an upper connection to crossover to other equipment. This nose is designed to pickup the cut off casings when laying on horizontal cased wells. When the casing is picked up further downward movement of the work string moves the cut off casing inside the OSP. The cut casing top moves through a set of hardened scrappers that clean the cut end of the casing OD before moving through an elastomer seal assembly. The cut top of the casing will come in contact with a “no-go” face and will stop downward movement of the work string (1m total movement). At this point, the upper equipment attached to the OSP, such as a new seal assembly can be set and released from the work string.
The OSP is designed to the existing casing’s size, weight, and grade and will retain the inside diameter of the existing casing. All other tooling attached to the OSP will also retain the minimum inside diameter of the existing casing. The OSP can also be removed from the existing casing by reattaching to the top of the OSP and applying a tensile load and an upward movement of 2m to completely disengage.
- To tieback to existing casings downhole.
- To create a seal on the tieback tool.
- scrapers to prepare the casing for the seal.
- Contains cold or thermal elastomer materials for sealing.
- Is mechanically set to casing or removed from casing if required.
- Can attach to down hole casings that are not centralized.
- Attaches to the outside diameter of the casing down hole, retaining the inside diameter of the casing on all tooling.