Intermediate Jacking Stations (IJSs) as inserted in the tunnel string at appropriate intervals to enhance and distribute thrust loads and facilitate longer drives. IJSs are designed to match a project’s exact pipe outside diameter. IJSs are custom built to match common RCP, steel casing, or CCFRPM pipe joints.
An IJS is recommended when the thrust pressure reaches one‐third of the pump unit’s maximum pressure capacity or half of the IJS thrust capacity. The IJS assembly comprises a non‐recoverable steel housing with multiple ram segments that each exerts additional thrust and is positioned on the steel housing’s interior ring.
IJS cylinders are controlled by the pump unit operator with a line holder cable, connected to hydraulic hoses and spool valves in the tunnel. IJS function can also be controlled through the ABIS system Monitor for automated injection.
- Used to extend drive length potential by distributing thrust load for longer drives
- Sealed to prevent intrusion of ground into the tunnel
- Comprise a non‐recoverable steel housing with multiples of ram segments that each exert additional hydraulic pressure
- Customized to match the outside diameter of the project pipe
Intermediate Jacking Stations (IJSs)
|Length of Stroke Cylinders||Qty. of Thrust Rams||Capacity Per Ram @ 8,000 psi|
Our interaction with Akkerman began on a project where we were struggling with their competition’s machine. Changing machines during a project to their machine required a leap of faith on our part. That project completed 20 years ago turned out to be successful and propelled us into 20 years of completing scores of successful micro tunnel projects throughout North America. Providing many innovations throughout this time has allowed us to mine many geology types and increase drive distances with curves to over 2500 lf. I can attest 30 years ago, technology did not exist that today allows us to complete projects efficiently and at a lower cost. Their leadership in providing technically superior AMERICAN made equipment is second to none in the world today.