Pulling Tools
PULLING TOOLS were designed primarily to retrieve subsurface locking devices and other downhole Wireline Service Equipment from the tubing bore. These downhole tools have a fishing neck, or the pulling neck, machined near the upper end for the Pulling Tool to engage and latch, hence retrieving it to the surface.
There are two types of Fishing Necks: internal and External. Hence, there are two types of Pulling Tools: those for the External Fishing Neck and those for the Internal Fishing Neck.
Both types of Pulling Tools are constructed so that they may be released from the subsurface device in the tubing bore in the event that the device becomes stuck and cannot be retrieved. This release feature is accomplished by a shearing pin installed in the Pulling Tool; once sheared, the design of the Pulling Tool releases the device.
The jarring action to shear the pin may be upward or downward, depending on the Pulling Tool used. Thus, the name SHEAR UP or SHEAR DOWN Pulling Tool.
Once the type (there are several types, depending on its function) of the PULLING TOOL is identified as being used to retrieve a sub-surface device, a REACH should be considered. REACH refers to the distance from the bottom of the core to the engaging surface of the dogs. That is, the Pulling Tool must engage or latch the Fishing Neck fully in order to be functional. This information is stated in the ENGINEERING DATA for each of the Pulling Tools, or it can be measured as shown in (see Fig 1).
