O'Reilly logo

The Guide to Oilwell Fishing Operations, 2nd Edition by Joe P. DeGeare

Stay ahead with the world's most comprehensive technology and business learning platform.

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, tutorials, and more.

Start Free Trial

No credit card required

Chapter 9

Impact Tools

Abstract

Simply stated, a jar is a delay mechanism. When installed in a fishing string and connected to a stuck object, a jar allows the operator the time required to pull and stretch the string. Using a hydraulic or oil jar, the pipe is pulled to a determined prejarring load while stretching the fishing string. The stretched drill string is held in tension, storing energy like a taut rubber band.

Keywords

Bidirectional hydraulic fishing jar

Bumper jars

Drilling jars

Fishing agitation tool

Intensifier jar

Jarring strings

Principles of jarring

Simply stated, a jar is a delay mechanism. When installed in a fishing string and connected to a stuck object, a jar allows the operator the time required to pull and stretch ...

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, interactive tutorials, and more.

Start Free Trial

No credit card required