Boring Machine

A horizontal boring machine or horizontal boring mill is a machine tool which bores holes in a horizontal direction. There are two main types — Table and Floor. The table type is the most common and, as it is the most versatile, it is also known as the universal type.

A horizontal boring machine has its work spindle parallel to the ground and work table. Typically there are 3 linear axes in which the tool head and part move. Convention dictates that the main axis that drives the part towards the work spindle is the Z axis, with a cross-traversing X axis and a vertically traversing Y axis. The work spindle is referred to as the W axis and, if a rotary table is incorporated, its centre line is the C axis.

Horizontal boring machines are often heavy – duty industrial machines used for roughing out large components but there are high-precision models too.

In machining, boring is the process of enlarging a hole that has already been drilled (or cast), by means of a single-point cutting tool, Boring is used to achieve greater accuracy of the diameter of a hole, and can be used to cut a tapered hole. Boring can be viewed as the internal-diameter counterpart to turning, which cuts external diameters.

There are various types of boring. The boring bar may be supported on both ends (which only works if the existing hole is a through hole), or it may be supported at one end (which works for both through holes).