The bumper sub (Drilling Subs) is usually installed in the drill string just above the fishing tool (overshot) or safety joint. Its presence in the string enables the operator to release the fishing tool in the event that it is needed in the fishing operations. It will deliver the sharp downward blow that is required …
The Releasing Overshot fishing tools (check our guide to successful fishing operations) are used to externally engage and retrieve all sizes of tubing, drill pipe, and casing. Here we will discuss its components including basket grapple, spiral grapple & controls. We shall also explain in detail its operations. Overshot: First choice tool because it does …
Overview When you are designing an overshot fishing assembly, you will need to select the: overshot size connection on the top sub grapple type grapple size pack-off type grapple controtype overshot guide type overshot extension size. Selecting the Overshot Fishing Assembly Size The OD of the fish and the ID of the hole determine which …
A cut made with a set of knives installed in a tool and run on a small diameter work string. This is referred to as an internal or inside cut. Internal mechanical drill pipe cutter MPC cuts are most common when removing sections of casing and wellhead equipment during final well abandonment operations. How Mechanical …
Chemical Cutter Wireline can be defined as an electric wireline tool and procedure that uses a propellant and a chemical, halogen fluoride, to burn a series of holes in the pipe, thereby weakening it so it is easily pulled apart (pipe recovery). This method of cutting pipe is the most recent innovation. It was patented …
Electric wireline service companies run instruments on conductor lines inside the stuck drill pipe or tubing and are able to accurately determine the stuck point (check also stuck point calculations) of the pipe. The instruments called free point indicator tools are highly sensitive electronic devices that measure both stretch and torque movement in a drill …
When a pipe becomes stuck in the wellbore for any reason, one of the first steps is to calculate to determine at what depth or point the pipe stuck has occurred. This process is called stuck pipe free point calculation. When retrieving production tubing from a well, it is often expected to find that the …
A fish is defined as any undesirable tool, piece of equipment, or other object found in the cased or uncased wellbore that stops or retards routine operational progress. Fishing in drilling oil and gas wells industry can be defined as any operation required to remove undesirable objects (the fish) from the wellbore. Fishing requires the …