Editing Wireline (cabling) (section)

===Head catcher===
A head catcher (also called tool catcher) is a device placed at the top of the lubricator section.  Should the wireline tools be forced into the top of the lubricator section, the head catcher, which looks like a small 'claw,' will clamp down on the fishing neck of the tool.  This action prevents the tools from falling downhole should the line pull out of the rope socket.  Pressure is applied to the head catcher to release the tools.