raise borer

mining

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Last updated

July 13, 2026

Quick Summary

A raise borer is a mechanized tool used in mining and underground construction to create shafts. It operates by rotating a cutting head that is pulled upward through a pre-drilled pilot hole. This method simplifies the removal of excavated material, as it falls directly into an existing tunnel below. The raise borer significantly reduces construction time and cost compared to older methods, allowing for faster excavation of shafts up to 1,000 feet with diameters of 3-8 feet. This technology has become widely adopted for shaft raising, especially in projects designed to take advantage of its efficiency.1

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tunnels and underground excavations
Shaft raising
…developed a device called a raise borer, in which the cutting head is rotated and pulled upward by a drill shaft in a down-drilled pilot hole, with the power unit being located at top of the pilot hole. The capacity of this type of borer (or upward reamer) generally ranges…
Read More
…developed a device called a raise borer, in which the cutting head is rotated and pulled upward by a drill shaft in a down-drilled pilot hole, with the power unit being located at top of the pilot hole. The capacity of this type of borer (or upward reamer) generally ranges…
Read More