The part of a drilling tool or machine that holds the bit.
- Between each drilling stage, however, when the drillstock of the rod-installing apparatus is disconnected from the rod to enable the addition of another section to the same, it is necessary to maintain the pressure in the tunnel by other means.
For editors and proofreaders
What do you find interesting about this word or phrase?
Comments that don't adhere to our Community Guidelines may be moderated or removed.