Geonex Start Casing provides a controlled and reliable entry point for all HDD projects
The method enables deep and accurate casing installations in all geology types, improving the overall success rate of HDD operations.
Why Use Start Casing?
Start casing is essential for creating a stable and secure entry point in HDD (Horizontal Directional Drilling) operations—especially in rocky or mixed ground. It ensures proper return of drilling fluids and helps prevent surface fluid loss or frac-outs. With a start casing in place, the pilot bore begins in controlled conditions, reducing project risk, improving steering accuracy, and enabling HDD use in areas where direct surface drilling would be unreliable.
How the Process Works
The process begins with the installation of a steel casing using Geonex Horizontal Hammer Boring, which pulls the casing into position with high precision—even in uneven terrain or hard ground. Once the casing is in place, the HDD drill string starts inside the protected entry, where the casing stabilizes the zone and contains drilling fluids, allowing the pilot bore to advance smoothly into undisturbed ground.
Case Examples – Proven method
Geonex start casings have been used in a variety of demanding HDD projects worldwide—from urban utility crossings to environmentally sensitive wetland installations. Examples include Ø406 mm and Ø914 mm casings in Sweden, Finland, and the U.S., where traditional HDD entry methods were either too risky or ineffective due to surface conditions or fractured rock. With the start casing in place, contractors achieved greater accuracy and significantly reduced the need for grouting or remediation.
Technical Specs and Maximum Diameters
Geonex start casings are available in diameters up to Ø1219 mm (48”), with blind hole installations possible up to 1.0 m ID. The system supports casing installation depths of over 100 meters, depending on geology and rig setup. All components—from ring bits to DTH hammers—are engineered to match casing dimensions, ensuring full compatibility and optimized drilling efficiency across different conditions.