Bottom Hole Assembly BHA Components and Design
The drilling bottom hole assembly (BHA) is one of the components of the Drilling String which is below the Drill Pipes. The most common components of the BHA are Drill Collars, Stabilizers, Shock Absorbs, Jars, Reamers, Heavy Weight Drill Pipes, and The Drilling Bit.

The purpose of the Bottom Hole Assembly BHA is to drill a usable hole economically.
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