Download award for significant contribution to land based pipeline technology

AWARD FOR SIGNIFICANT CONTRIBUTION TO
LAND BASED PIPELINE TECHNOLOGY 2013
Entry Form
th
Entry Deadline: Monday, 28 January 2013
1.
Brief title of entry:
Preston Sewerage Scheme Twin Direct Pipe Tunnels ....................................................................
2.
Company name:
J. Murphy & Sons Limited / KMI Water ............................................................................................
3. Summary of entry:
Completion ahead of schedule of the Preston Sewerage Scheme included several notable achievements; the first use
nd
in the UK of the Herrenknecht Direct Pipe technique, the world’s 2 longest Direct Pipe drive and setting a UK pipe
jacking record with 72m successfully achieved in a single 12 hour shift.
J. Murphy & Sons Limited and KMI Water JV team, United Utilities, GHA Livigunn and Herrenknecht worked
collaboratively to provide an innovative, safe, efficient and technologically advanced ground engineering solution.
The £114m sewer improvement scheme in Preston for United Utilities and its capital programme has involved a
complex mix of interceptor sewers, stormwater storage tunnels, 6km of tunnelling, rising mains and 13 access shafts.
The scheme will upgrade the city’s aged sewer system, and improve the quality of the Fylde Coast bathing waters and
designated shellfish beds in the Ribble Estuary.
Applying existing technology in new areas
The twin tunnel river crossing provides the only link to take sewer flows across the river to the treatment works. The
success of this element was crucial to the overall project. Working in partnership with German operator Herrenknecht,
the collaborative Murphy / KMI engineering team undertook an innovative approach to construct twin 1.4m diameter
steel pipe drives beneath the River Ribble.
Providing the pipeline industry with a technique it didn’t have before
The Direct Pipe microtunnelling technique has been employed in mainland Europe for several years with much
success, but had not been used in the UK prior to this project. The new technique focuses on a powerful pipe-thrusting
machine anchored in a shallow pit at the start of the under-river drives. This allowed the pipeline to be gripped by the
thruster and forced through the ground by the machine’s pistons in 5m strokes. Strings of welded pipes are then thrust
forward through the river bed’s glacial sands, silts, gravels and boulders. Heading up the pipe string is a 15m long
micro tunnel boring machine (TBM) which is fully computerised and operated remotely from a control room.
Cobbles and boulders were easily disposed of by a cone crusher mounted on the head of the microtunnelling
machine. The resultant spoil was then mixed with a bentonite slurry to feed-back, through slurry lines within the
completed pipes, to a surface separation plant. Waste management measures were established whereby the slurry
was filtered and given to a local landowner as fill material.
A back-up facility was set up to extract the entire pipe string in case major obstructions were encountered but this was
not required. Lubricating the 60mm annulus around the pipe with a bentonite and polymer mix allowed a maximum
thrust of only 450t to be applied, just 60% of the pipe thruster’s capacity.
Achieving a degree of accuracy of +/- 1mm, the 866m twin pipe western river crossing was successfully completed a
month earlier than programmed. The crossing of the River Ribble represents the only link to the Clifton Marsh
Wastewater Treatment Works, this emphasises its importance and value to the project in realisation of the
environmental enhancement and benefits to the community.
A step forward in cost reduction, improved safety and environment measures and performance
Opting to use the Direct Pipe technique cost less than half of any other option, selecting this option resulted in
significantly quicker progress as this element of the overall scheme was completed 1 month ahead of schedule, thus
successfully marking the techniques entrance into the UK pipeline construction sector for future use.
Drive progress averaged 20m a day and in spring 2012 the Murphy led engineering team claimed a new UK pipejacking record of 72m in a single 12 hour shift. Furthermore, the smaller diameter Direct Pipe machine resulted in less
spoil and waste than use of a larger 3m TBM.
New opportunities for the pipeline industry - a technique which has possible future applications
Another positive benefit of Direct Pipe use was a reduction in risk to operative Health & Safety as remotely controlled
pipe jacking eradicated operative entry requirement. Achieving longer tunnel drive construction progress has now
become possible as operatives are no longer required to be positioned at tunnel cutting interface during tunnelling
operations and thus can provide a construction method in lieu of traditional man entry tunneling.
4.
Signed:
J. Fitzgerald ...................................................................................................................................
5.
Date:
25/1/2013 .......................................................................................................................................
6.
Company contact name: Justin P. Fitzgerald (Communications & Marketing) ......................................................
Telephone:
07834 677 499 / 020 7692 9467.................................................................................................
Email:
[email protected] .......................................................................................
Detailed Description of Entry
(Entry restricted to normal type face and font size on this form plus one page A4 drawings or photograph)
Gripper Installation on the Thruster at launch
TBM entering the eye seal
Control cabin for the microtunnelling at River Crossing
Detailed monitoring of the drive progress – the crossing was completed to a +/- 1mm degree of accuracy