Summary

This review describes the process and equipment used in raiseboring. Several definitions are given, as well as links to courses and publications related to raiseboring. A list of mines using the raiseboring method, and a list of contractors and consultants specializing in this method are given.

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INTRODUCTION

Raiseboring brings up fewer than 300 Google entries. When written as 2 words, raise boring brings up nearly 1.5 million. Regardless of how many words you use there is a lot of information out there. Here are my picks that hopefully provide a guide to your technical, scientific, and engineering interests.

DEFINITIONS

From a 1980 paper, Productivity in Platinum Mining: Traditional shaft sinking methods involve making a hole in the ground which is progressively deepened until the required depth in the earth is reached. If underground access is already available to the position of the bottom of the proposed shaft, the method known as raiseboring may be employed. Rustenburg Platinum Mines has successfully used this technique during the development of their underground program. It involves boring a pilot hole vertically downwards to the existing access at the bottom of the proposed shaft and then reaming upwards, that is enlarging, from the lower access point such that the diameter of the hole is the required shaft width. The broken rock falls to the bottom of the hole and the technique allows for greater flexibility in handling the spoil. In addition to lowering costs and saving time, the safety hazards associated with the older methods have been reduced significantly.

The InfoMine dictionary includes these definitions:

• Raise: (1) A vertical or inclined opening in a mine driven upward from a level to connect with the level above, or to explore the ground for a limited distance above one level. After two levels are connected, the connection may be a winze or a raise, depending upon which level is taken as the point of reference. (2) A mine opening, like a shaft, driven upward from the back of a level to a level above, or to the surface. (3) To take up the floor or bottom rock in a room, gangway, or entry to increase the height for haulage.
  
• Raise Borer: These machines are used to produce a circular excavation either between two existing levels in an underground mine or between the surface and an existing level in a mine. In raise boring, a pilothole is drilled down to the lower level, the drillbit is removed and replaced by a reamer head having a diameter with the same dimension as the desired excavation and this head then is rotated and pulled back up towards the machine.
  
• Raise Climber: Equipment used in an opening (raise) that is mined upward.

Wikipedia has a similar, if less literate definition.

Atlas Copco provides a good description of the basics and a couple of fine figures to show how it all works. Here is one of their figures: