Pipe Jacking

Direct Pipe Laying Machine

The direct pipe laying machine pairs a slurry-balance TBM with a pipe thruster, with the pipeline welded to the machine tail and pre-laid for hundreds or thousands of metres before excavation begins. As the TBM advances, the pipeline is jacked continuously into the ground, so excavation and pipeline installation complete in a single pass with no in-tunnel pipe joining and no reception shaft.

Used inPipe-Jacking Package

Direct Pipe Laying Machine direct pipe laying in operation — Direct pipe laying in operation

Working principle

A direct pipe laying machine excavates the tunnel like a pipe jacking machine using slurry pressure balance for face support. The machine is built around two parts: a tunnel boring machine at the face and a pipe thruster at the launch side. The distinguishing feature is that the tail of the TBM is welded to the pipeline, which can be pre-laid for hundreds or even thousands of metres before excavation starts.

As the machine advances forward, the pipe thruster jacks the pipeline into the ground behind the TBM, so pipe installation never breaks the drive. When excavation finishes, pipe laying is finished too. A reception shaft is not required; the machine can also be retracted by the pipe thruster at any point, which keeps options open if obstacles are encountered or the drive needs to be aborted. A safe-thrust technology protects the anticorrosive coating on the steel pipeline, and a high-precision guidance system holds line and grade through to breakthrough.

Features

Pipeline welded to the machine tail and jacked continuously as the TBM advances, removing in-tunnel pipe installation steps

Continuous one-pass drives up to 1,000 m with peak advance to 100 m per day; field-proven 200 m bored in 2 hours without stoppage

Slurry-balance support method controls face pressure and limits ground settlement; the machine can be retracted by the pipe thruster if needed

Construction angle from -15 degrees to +15 degrees, suiting river crossings and grade changes that conventional jacking cannot reach

No reception shaft required, lowering surface footprint and overall project cost

Cutterhead configured per ground conditions, with safe-thrust technology that protects the anticorrosive coating on the steel pipeline

Specifications

Bore diameters supplied	1,300 mm and 1,505 mm (2 machines)
Length (shield + back-up)	14 m
Total weight	200 t / 270 t
Maximum thrust	5,000 kN / 8,000 kN
Installed power	770 kW / 820 kW
Maximum advance rate	5 m/min
Construction angle	-15 degrees to +15 degrees
Recorded performance	Continuous 200 m drive in 2 hours without stoppage

Reference projects

Eastern China oil pipeline project
Location
Eastern China
Diameter
1,300 mm and 1,505 mm
Machines
2
Configuration
Continuously tunnelled 200 m within 2 hours without any failure; max thrust 5,000 kN and 8,000 kN; installed power 770 kW and 820 kW; total weight 200 t and 270 t; max advance rate 5 m/min; construction angle -15 to +15 degrees

Project	Location	Diameter	Machines	Configuration
Eastern China oil pipeline project	Eastern China	1,300 mm and 1,505 mm	2	Continuously tunnelled 200 m within 2 hours without any failure; max thrust 5,000 kN and 8,000 kN; installed power 770 kW and 820 kW; total weight 200 t and 270 t; max advance rate 5 m/min; construction angle -15 to +15 degrees

Applications

Small-diameter water diversion tunnels, water drainage tunnels, oil and gas pipeline laying, and other long-distance pipeline installations where a single-pass trenchless drive is preferred to open-cut or shaft-based methods. The construction-angle range and continuous-drive capability suit river crossings, grade changes and long peri-urban pipeline runs across AU procurement scenarios that involve operational highways, watercourses or sensitive surface land. The published international reference is the Eastern China oil pipeline programme, where two CRCHI machines recorded a continuous high-rate drive without stoppage.

Configuration and engineering

Every CRCHI TBM is engineered to project. Shield diameter, cutterhead geometry, drive power, segmental ring design and back-up arrangement are configured to the alignment, ground conditions and water pressure of the drive. Project-specific scope beyond the standard envelope is engineered to brief, and where a drive calls for it, a machine is developed from the ground up. CRCHI Australia is the engineering, commercial, commissioning and aftermarket point of contact for Australian projects.