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Eccles WwTW - Hyperbaric Equipment

Eccles WwTW - Hyperbaric Equipment

1.8.2015

Working at Eccles Waste Water Treatment Works, GallifordTry-Costain-Atkins JV (GCA JV) recently commenced their first 1200m drive, using a Lovatt 131 Tunnel Boring Machine (TBM). Through early planning, GCA JV recognised the potential need for Compressed Air in order to allow the team the ability to change cutting tools on the face of the machine and conduct any other TBM interventions that may be required.

With Specialist Plant's expertise and years' of experience, a new design of 'Top Hat' style bulkhead (fitted to the eye of the tunnel) was used. This design fits into the mouth of the tunnel, and is held in place using the original TBM jacking rig. This allows the bulkhead to be taken in and out easily, saving day's of labour and time, especially when compared to the conventional 3-bulkhead method which would need constructing and de-constructing before and after each intervention.

Why we use Bulkheads

Bulkheads are used at the tunnel mouth to prevent air escaping from the tunnel and allows you to put more air into the tunnel, to compress it, pressurizing the tunnel. The bulkhead effectively acts as a seal, preventing any air from escaping the tunnel. It is used ordinarily in interventions (when a Tunnel boring Machine needs its face inspecting to check the quality of the tooling), to support ground pressure.

To allow the workers to inspect the tooling, they must stand in-front of the TBM exposing themselves to unsupported ground, which could potentially collapse. Compressed Air is used to support the face by using a ‘pressure’ of air to prevent the ground closing in.

Additional Hire Equipment

Over the period of the project, we also supplied; Air Manlock, Medical Decompression Chamber, Air Process Container, Medical Office and Compressed Air System components.