Grindex Dewater The Dublin Port Tunnel

27/01/2004

Two leading names in the international construction industry, Nishimatsu and Mowlem, are currently right on schedule to complete construction of the 4.5 km twin bore Dublin Port Tunnel for its end 2004 deadline. Euroflo Fluid Handling are working closely alongside these two major companies for the supply of submersible drainage and sludge pumps. From their Dublin offices Euroflo has provided Grindex pumps to meet the ever-changing site requirements as well as technical and engineering support virtually around the clock to co-incide with construction programmes. It's hard to keep track of the number of Grindex submersibles on site at any one time but the figure currently stands around 30 units.

Starting at the 'sharp end' and mounted directly on the tunnel boring machine a 100mm capacity Grindex Major is part of a water/cooling liquid re-cycling system but, as with any drilling operation, there will be a requirement for residual disposal and positioned in close proximity to the TBM an 80mm Grindex Minor pumps a very abrasive mix of slurry content containing particles of a general nature created on the site and also crushed limestone back to the start of the tunnel. At this point two Matadors, working in tandem, then move the discharge some 26m to the surface. These two pumps, with their150mm pipe capacity, have been in situ for over two years within no operational problems apart from being returned twice to Euroflo for cleaning. At surface level the discharge then transfers to a water treatment plant and here four Grindex Major pumps are being used in the process.

Quantities of smaller 50mm Grindex 110v Minex units are also constantly in use, both within the tunnel itself and for general site dewatering requirements. All 50mm Grindex pumps supplied to the project by Euroflo are 110v to comply with site safety requirements and especially customised to cope with the harsh requirements.

Nishimatsu Plant Officer, Krishna Rajbhandari has worked closely with Euroflo's technical specialist, Derek Anderson and speaks highly of both Grindex pumps and the Euroflo service. He comments: 'we looked carefully at specification and performance data from a number of suppliers prior to commencement and even set competitive pumps up against each other for site evaluation. The Grindex pumps we have are certainly achieving everything asked of them.' He is also looking for the ideal opportunity to use the new Grindex Tuff Solo Sludge Pump that he now has for assessment. Judging from reaction elsewhere he will find this pump lives up to the now well respected Grindex reputation and will be able to cope with virtually anything asked of it.

Nishimatsu are the contractors carrying out the tunnel drilling aspect of the project but elsewhere Mowlem are making extensive use of large capacity Matadors for general drainage throughout other areas of the construction site. These particular pumps are capable of moving 45 litres per second to a head height of approximately 60m.