Precision drilling next to a lock: First gyro drill for our client

On behalf of the network operator, the power grid in this area is being expanded with new cable connections. To establish a connection under the Kadoelermeer, a horizontal directional drill was designed.

The HDD crossing ran parallel to a road over a lock, the Kadoelerkeersluis. The drill was designed to curve around the infrastructure of the lock and bridge. This required a large horizontal curve. This coincided with the vertical curves, resulting in a complex drill trajectory.

Contractor Van Lenthe Dalfsen was able to rely on Brownline's steering service for surveying this job. It was the first time that this client carried out a drill with a gyroscopic steering system. Given the complexity of the crossing, the Drillguide Gyro Steering Tool was the best solution to achieve an accurate pilot bore.

A large horizontal curve of 51° was steered around the lock. The combination of horizontal and vertical curves created a combined radius of 156 m / 512 ft. Accurate real-time position measurements were therefore of great value for the successful progress of the pilot drill.

With GPS track, it was possible to perform additional checks from surface level before and after crossing the water. This provided more assurance and reduced the risks for the project.

While crossing the water, it was also important to prevent drilling fluid from leaking out of the borehole. With Pressure-While-Drilling, the pressure in the borehole was continuously measured during drilling. By keeping the pressure under control, the risk of a blowout was reduced, allowing for safe and efficient drilling.

Thanks to the precision, efficiency, and good cooperation between all parties involved, the pilot bore hit the exit stake perfectly.