CREG Retractable Circular Full Face Pipe Jacking Machine Ready for Sewer Tunnel in Hong Kong

On May 19, 2025, the retractable circular full face pipe jacking machine “CREC1563,” manufactured and developed by China Railway Engineering Equipment Group Co., Ltd. (CREG), successfully completed its Factory Acceptance Test. It will be used to bore the Kwu Tung and Cheung Sha Wan Sewage Pipeline Projects in Hong Kong. This pipe jacking machine innovatively adopts a foldable cutter head and a retractable design, which can improve the ability to handle complex conditions and greatly enhance convenience and security.

This project is characterized with the complex geological conditions such as gravel, a narrow launch shaft space (3.1m in length and width) and high construction risks of passing through a section of subsea area. Therefore, the machine adopts a compact design with the excavation diameter of 3.04m and the front shield and tail shield lengths of less than 3.1m, which can satisfy lifting in a narrow launch shaft space.

For high-risk subsea construction, there is a potential risk of abnormal cutter damage and excavation difficulties when encountering gravel layers. To address this, an innovative retractable design has been adopted. The machine features a dual-shell shield structure and a foldable cutter head. Specifically, when the machine encounters challenges during subsea construction, the retractable pipe jacking machine can realize breakout by retracting the cutter head and withdrawing it together with the inner shell.

The circular pipe jacking machine is a type of trenchless equipment used for underground tunnel construction, which features multiple types, full-size coverage and wide geological adaptability. The pipe jacking machine manufactured and developed by CREG mainly includes earth pressure balance, slurry balance and multi-mode types, with diameters ranging from 0.4m to 4m. They are suitable for various geological conditions such as silt, clay, sand, gravel, soft soil, hard rock and composite strata, and can be widely applied in the construction of underground tunnels including water supply and drainage, communication cables, gas pipelines, power cables and utility tunnels