General Description
The Taper Tap is an internal catch tool. It is made up of one piece and looks very much like a tap used to tap threads in a nut. It differs by having a long taper to accommodate different I.D. sizes of the fish. A Taper Tap may be one inch O.D. on the end and taper to 6 ¼ inches at the top. Some have flutes and some do not. The ones without flutes are used when you want to form a seal so you can pump through the fish. The fluted ones will usually screw deeper into a fish.
Use
The Taper Tap is used to engage and retrieve tubing, drill pipe, casing, and other similar tubular items having bores, from any bore well. They are particularly valuable in cases where the area between the fish and the well bore is too narrow to permit engaging the outside diameter of the fish by external catch tools.
Construction
Standard Taper Taps are not threaded for Guides. Threads will be provided on special orders at extra cost for attachment of a Guide or Skirt and Guide (or Oversize Guides).
Operation
The Taper Tap cannot be released. In some cases, you might back one out of a fish by applying left-hand torque, but extreme caution should be used when applying left-hand torque to avoid backing the string off elsewhere.
The Taper Tap is very easy to run. Run it in the hole to the top of the fish. When you think you have it in the top of the fish, rotate to the right with a neutral weight until it torques up whatever amount you need. It is a good idea to let the torque out and make it up again several times before pulling or jarring on the fish. If you pull or jar any length of time, it is a good idea to torque the Taper Tap periodically while doing this to keep it tight in the fish.
The Taper Tap will pull or jar out of the fish fairly easily because of the taper and shallow threads it cuts.
Some thought should be used before running a Taper Tap. If you have a piece of thin pipe or split pipe looking up, you would not run a Taper Tap, because it would only split the fish further as you screwed the Taper down in the fish. The Taper Tap works well on drill collars, in the top of the tubing collar, or upset and in a drill pipe tool joint. Like all other fishing tools, there is a place for the Taper Tap. This should be well thought out before running it or any other tool in the hole.
The Pip Tap is the same as the Taper Tap, except it is very short and used mostly to screw into the box of a tool joint.