Network Rail first noticed potential areas for improvement working with Amey on CP6 tunnel refurbishments that require two operatives working at height in full personal protective equipment manually holding a drill to carry out maintenance work. The risk of hand arm vibration injuries, noise, inaccuracies, and dust contamination were all potential factors operatives faced using the manually-held drill.
Working with Foulstone Forge, Network Rail, and Amey, the team created a drilling rig machine for work undertaken in railway tunnels. The Overhead Line Electrification Drill (OLED) machine is mounted on a flat bed of a road rail vehicle. The machine can be operated by a member of the team who not only controls the base unit but the drilling arm via the remote control as well, removing the risk involved of operatives working at height and using rotary-percussive power tools. The machine also has a comprehensive dust extraction system fitted to the unit to eliminate any dust from the drilling, improving the working environment for operatives.
The machine was first tested at High Marnham Test track on a section of brick tunnel works. Part of the features of the drill, is that due to the mechanical control of the arm, it has the ability to work around tunnel furnishings including cables, utilities and overhead line electrifications.
Having a four-head drill capacity built in, this new drill has quadrupled the outputs, making the process more efficient and cost effective. The machine now takes just under two minutes to drill four holes 450mm deep into concrete using 28mm drill bits.
The progress and accuracy of the drill is now controlled using a remote-control unit that monitors the progression of the drill and the force applied with operatives standing away from the area. Having four drill heads has enabled the machine to be set up so that any of the individual drills can be used in isolation in any configuration, allowing differing bolt patterns to be installed using the same drilling head.
Amey’s rail team has recently completed the trials. The next stage is to use the drilling rig within the Watford and Shugborough and Birmingham mid-life refurbishments of the overhead line electrification infrastructure within the tunnels.