In certain special situations it may be preferable to employ pipejacking techniques. This may be where short drives near to the surface are needed, but open cut excavation is not possible, either because of the disruption that would be caused or because of other services that are present and which make open cut excavation impractical.
Standard Pipejacking Machines
φ 3200mm EPB type is the largest pipe-jacking machine that CREG have manufactured to date.
This Pipe Jacking Machine was specifically designed and manufactured for a main sewage project in Zhengzhou. The total length of the project is 32 kilometer. At an estimated value of 82,000,000 U.S. dollars, it is the largest pipe jacking project in Central China.
- The machine has with a mixed face cutterhead mounted on a central drive.
- A screw conveyor removes muck from the cutterhead under EPB conditions
- A positive displacement pump transports the excavated muck to the surface.
- An advanced guidance system is used to steer the machine with
- CCTV monitoring underground enables control and operation of the system from the surface.
The geological conditions of the project in Zhengzhou are quite complex, consisting of saturated sand and clay layers with a high water table. Maximum jacking lengths of xxxxx.metres will be used meaning that xxxx.number of shafts will be required for the 32 km project length. The main jacking station will incorporate a maximum thrust capability of xxxx Tones.