REFURBISHMENT AT
CULLIGRAN POWER STATION diamond wire saws

As part of a recent refurbishment programme at Culligran Power Station in Scotland, it was necessary to remove the Turbine Runner Chamber ready for replacement. As this task required total control of the cutting process with the minimum of waste, methods such as hydro demolition were ruled out because of the possible resultant mess and lack of control. Thermic lancing was also considered unsuitable as the power station installation is located in an underground cavern.

Therefore Millar Reid, a director of one of our DSA Supplier Members – UKDIMA Ltd of Stirling - was called in by the local drilling and sawing contractor, H & F Specialist Services Ltd, to assist in devising a suitable method involving diamond cutting. The main contractor on behalf of Scottish and Southern Electricity was Weir Engineering/VA Tech.

Ukdima had recently sourced a radial sawing machine and thought that this type of machine could be utilised on this project. As a result of his visit, Millar Reid concluded that the task could be carried out with relative ease using diamond cutting technology. Firstly, weld preps would be machined into the Runner Chamber at the top and bottom of the area to be removed. A radial saw would then be mounted onto the chamber and four radial cuts would be made to form a chase around, which would then be removed. A modified circular wire saw would then be mounted on a special frame manufactured by the drilling and sawing contractor as it was necessary that the circular saw should cut round the chamber without touching the weld prep.

In addition to the main concrete structure, the diamond saws were also called on to cope with cutting the cast steel runner chamber, anchor irons, anchor struts and rigging screws.

In addition to the diamond saw blades and the diamond wire, the RD3500 Radial Saw and the Circular Wire Saw were supplied by UKdima specially for this project. Also Ukdima set up the machines ready for work and then provided a high level of ongoing site support. The RD3500 Radial Saw can cut up to 3500mm diameter pipes.

As part of the H & F Specialist Services team, UKdima assisted in providing professional and innovative solutions to a difficult project. As a result, this part of the work was completed ahead of schedule and within budget to the satisfaction of the main contractor.