Deep Hole Drilling Process For Bailey Bridge Components

The components of a Bailey Bridge that require the deep hole drilling process include:

Connection holes between truss chord members and web members: This is the most typical application for deep hole drilling. These holes accommodate the insertion of pins, which bear the primary shear forces.

Connection holes for reinforced chord members.

Pin holes in the truss connecting pins (e.g., for grease injection holes, if present on the pin itself).

Critical connection holes in components such as transverse beams and deck panels.

The common characteristics of these holes are: high dimensional accuracy of the aperture (typically to H7 grade or higher), relatively great depth (compared to the diameter), high required surface finish of the hole wall, and mandatory concentricity of hole alignment when multiple truss sections are stacked together.