CPD, also known as shell and auger drilling, uses a large tripod rig and winch to lift and drop a cutting tool inside a steel casing tube. This case maintains stability and prevents the borehole collapsing from any insecure soil. The cutting tool used is dependent on the type of ground substrate.
[pdf] Geotechnical drill rigs are specialized equipment for the rigorous demands of construction and geological projects. These rigs play a key role in geotechnical investigation, providing the capability to assess ground conditions.
[pdf] The Boyles C5/C5C surface core drilling rig is compact, yet powerful. Its compact design makes it easy to position and transport, even by helicopter. During helicopter transport, the rig is broken dow.
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