Drilling Jar | Placement, Types, Calculations & Operation
Selecting Drilling jars is a major step in drill string design. Here we shall cover the Drilling jar working principle, placement, types, operations & calculations.

In general, the purpose of drilling jars placement in the BHA is to generate upward or downward impact loads to free stuck pipe or release a fish. There are many factors that affect the decision of when to use jars and where to position them for maximum benefit.
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