The Series 150
Releasing and Circulating Overshot is an external fishing tool used to engage,
pack off, and recover tubular fish from the wellbore. It is especially
effective for retrieving drill pipe, drill collars, and other tubular
components during downhole fishing operations.
The overshot consists of three primary external components:
- Top Sub
- Bowl
- Standard
Guide
Depending on the fish size, the overshot can be equipped with different
internal grapple systems:
- Spiral
Grapple assembly for fish sizes near the maximum catch range
- Basket
Grapple assembly for smaller fish sizes
This flexible
configuration allows a single overshot body to handle multiple fish diameters
efficiently by changing the grapple components.
The tool can
also be equipped with several optional accessories to improve engagement and
recovery performance in complex fishing environments, including:
- Extension
Sub
- Wall Hook
Guide
- Oversize
Guide
- Mill
Extension
- Mill
Guide
These
accessories improve fish alignment, centralization, milling capability, and
engagement efficiency during difficult retrieval operations.
Key Features
- External
fishing tool for tubular recovery
- Releasing
and circulating capability
- Interchangeable
Spiral Grapple and Basket Grapple systems
- Available
in Full Strength (FS) and Slim Hole (SH) configurations
- High-strength
bowl and grapple construction
- Compatible
with multiple fishing accessories
- Efficient
circulation during fishing operations
- Designed
for complex downhole fishing environments
Optional
Accessories
Extension Sub
Used when the upper portion of the fish is damaged and difficult to engage.
Allows the overshot to pass further over the fish for secure engagement and
pack-off.
Wall Hook
Guide
Designed to capture and centralize fish located in washed-out hole
sections, guiding the fish properly into the bowl.
Oversize Guide
Ensures proper fish alignment when the hole size is significantly larger
than the fish diameter.
Mill Extension
Features Incoloy-faced interiors to mill away flared or jagged fish
sections for easier engagement.
Mill Guide
Used to trim badly damaged or flared fish tops to facilitate overshot
entry.
Applications
- Drill
Pipe Fishing Operations
- Drill
Collar Recovery
- Tubular
Fish Retrieval
- Washover
Fishing Operations
- Circulating
Fishing Applications
- Slim Hole
Fishing Operations
- Deep Well
Fishing Operations
- Milling
& Fishing Combination Operations
Advantages
- High
retrieval success rate
- Flexible
grapple system for multiple fish sizes
- Efficient
debris circulation during operations
- Reduced
non-productive time (NPT)
- Improved
fish alignment and engagement
- Reliable
performance in damaged or washed-out holes
- Strong
structural integrity for high-load fishing operations
- Easy configuration adjustment for different fishing conditions
