A Rathole is a temporary storage space that is 30 to 35 feet deep, lined with casing that projects above the floor, and used to store the kelly and swivel. This is either done by the portable rig that drills the conductor hole or can be done by the primary rig after rigging-up.
[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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