Glenlee Power Station

The 12MW Glenlee hydro-electric power station in Scotland is part of the 106.5MW Galloway Hydro-Electric power scheme, which was the first large scale integrated hydro-electricity supply complex in the UK when it was built and commissioned in the mid 1930s. A 60km long network of lochs, dams, tunnels, aquaducts, pipelines and rivers interconnect six power stations in a cascade system, which reuses the water several times for power generation. Each station reuses the water that has been discharged by the one above to generate electricity.

Glenlee is the fifth of the six power stations in the interlinking renewable energy scheme that

covers a large area of Galloway and South Ayrshire. Water for Glenlee Power Station gathers

in Loch Clatteringshaws and flows through a 6km long tunnel to a portal control valve above

the power station. From here water plunges 125m down the hillside through a 570m long steel

penstock of varying diameter to the station’s twin 6MW turbines and out of tailrace valves and

into a spillway, for discharge into the River Dee.

The Glenlee penstock was in need of cleaning and repainting and power station operator Scottish

Power Generation Ltd awarded a contract for its refurbishment to the specialist contractor

Concrete Repairs Ltd based in Falkirk. The flange bolted steel pipeline had not been cleaned and

painted internally for over 70 years, since it was installed in the 1930s. CRL believed the internal

cleaning and paint removal could be done with high-pressure water jetting and contacted

N.E.T. Waterjet Ltd.

N.E.T. used its new Conjet 324, with optional rotor head, which arrived on site in May 2010, to

remove the build up of debris and old paint coating up to 4mm thick. The company had about

4,200m2 to clean from the inner surface of the penstock in diameters from top to bottom

of 3m, 2.7m, 2.4m and twin 1.8m and on varying gradients from 1:100 up to the steepest 18 degrees.

CRL removed the flange bolted expansion joints and butterfly valves in the penstock to provide N.E.T. access at several points for the Conjet 324, which was supplied with water at a pressure of 2,500 bar and flow of 25 litres/min from one of N.E.T.’s existing 250kW Hammelmann 120 high-pressure pumps.

There was no dust from the paint removal and the waste water and debris from the Conjet Robot cleaning process flowed down the penstock and was collected by CRL in a sump in the turbine house. It was then pumped into tankers for off site environmental treatment and disposal.

Glasgow Car Park

Removal of 10,000 m2 of concrete screed from the roof of a public car park in Glasgow for Land Engineering.  This was followed by removing the waterproof membrane and surface preparing the roof deck for Site Sealants who re-applied a new membrane.

Dollon Aqua Centre East Kilbride

Involved in the major refurbishment of the Dollon Aqua Centre, East Kilbride, which is a 20th century A listed building, which opened in 1968, and will be a key venue for the International Children’s Games in 2011. Clark Contracts asked N.E.T. Waterjet to remove the epoxy tile adhesive from the walls and floors of the pool at the end of 2009 and in April 2010 asked our company to return on the instruction of their client, South Lanarkshire Council, to remove the cementitious epoxy screed from the pool back to the main structure.

The Gyle Edinburgh

The deck blast with full vacuum recovery has been used to remove adhesive and epoxy floor paint from Industrial Unit floors at the Gyle, Edinburgh.  Using this same equipment we carried out the floor screed removal around the fermentation tanks at a distillery in Aberdeenshire.  The success of this contract allowed us to return to carry out work with a different UHP application to clean and polish inside the stainless steel syrup pipes.

Clyde Wind Farm

At Clyde Wind Farm we successfully removed a concrete plug from an electricalcable duct at a turbine base for C.A. Blackwell.

Aberdeen and Dundee Dry Docks

Working in both Dundee Dock and Aberdeen Dry Dock, we have used UHP to remove the protective coatings from hulls, decks and tanks on a variety of vessels.

Thornton Fife

Using our sawing and coring equipment we were involved in floor sawing expansion joints and diamond core cutting at a new egg production facility at Thornton in Fife.

Wind Turbine Base

April 2011-  Concrete was to be removed leaving the rebar insitu.

N.E.T.Waterjet Ltd was awarded the contract and using their Conjet 324 Robot and a 340hp

waterblast unit, running at 120 litres/min, the work was safely carried out. Using the robot

increased the volume of removal, and the Robot was able to operate both from the outer

ring and within the centre of the base.  This reduced any hand lance work, using a 125hp

waterblast unit, to a minimum on inaccessible areas. The main benefits of the Conjet 324

Robot are its versatility and manoeuvrability along with alleviating labour fatigue and the

associated safety risks.

LSA/NORM Scale Removal and Tube Bundle Cleaning – May 2011

Carrying out work at an Oil Terminal to safely remove LSA/NORM scale from pipework.

Using the Peinemann single lance system to efficiently carry out tube bundle cleaning.

The Peinemann enhances the safety aspect for the operator.

Galliford Try –Warrington – June 2011

Cutting recessed rings in core holes varying in size from 200mm to 350mm.  

This was carried out over approximately 1500 core holes for a new community

hub in Warrington.  Steel piles were driven down 10m through the core holes.  

These piles were then filled with concrete and the recessed rings act as shear lugs.

© NET Waterjet, Unit 1, Mid Friarton, King James Business Park, Perth, PH2 8EL