Editing Wireline (cabling) (section)

==Additional equipment==

===Cable head===
The cable head is the uppermost portion of the toolstring on any given type of wireline.  The cable head is where the conductor wire is made into an electrical connection that can be connected to the rest of the toolstring.  Cable heads are typically custom built by the wireline operator for every job and depend greatly on depth, pressure and the type of wellbore fluid.

Electric line weakpoints are also located in the cable head.  If the tool is to become stuck in the well, the weak point is where the tool would first separate from the wireline.  If the wireline were severed anywhere else along the line, the tool becomes much more difficult to fish.<ref>{{Cite web|url=http://ww38.wirelinehq.com/wireline-basics/cablehead/?subid1=20231006-0428-2204-b955-68baa94d5a06|title=wirelinehq.com|website=ww38.wirelinehq.com}}{{dead link|date=October 2023|fix-attempted=yes}}</ref>

===Tractors===
Tractors are electrical tools used to push the toolstring into hole, overcoming wireline's disadvantage of being gravity dependent.  These are used for in highly deviated and horizontal wells where gravity is insufficient, even with roller stem.  They push against the side of the wellbore either through the use of wheels or through a wormlike motion.

===Measuring head===

A measuring head is the first piece of equipment the wireline comes into contact with off the drum.  The measuring head is composed of several wheels that support the wireline on its way to the winch and they also measure crucial wireline data.

A measuring head records tension, depth, and speed.  Current models use optical encoders to derive the revolutions of a wheel with a known circumference, which in turn is used to figure speed and depth.  A wheel with a pressure sensor is used to figure tension.