Chapter 24

Thru-Tubing Fishing Jars and Accelerators

Abstract

In fishing operations, hydraulic jars are used to deliver an impact force to free the fish. Jars designed specifically for coiled tubing are generally flow-through and torque-transmitting. They are available in single-direction and bidirectional versions. The most commonly used jars are the hydraulic, time-delayed type. This jar does not rely on stored energy within the tool itself to regulate the force of impact. Instead, the hydraulic jar uses a fluid-metering system to regulate fluid transfer between the cavities of the tool when tension is applied by the coiled tubing.

Keyword

Accelerator jar

Bidirectional vibratory jars

Dual-acting jars

Hydraulic jar

Thru-tubing fishing operations ...

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