Preparation for cathodic protection using Conjet equipmentPublished 28/12, 2016 at 16:19
The Swedish port of Kapellskär is about 80km north of the capital, Stockholm. A large number of trucks use this port as it shortens the time at sea, compared to using the port from city centre in Stockholm. A large number of ferry boats for Finland dock here which makes Kapellskär an important logistic part of the infrastructure around the Stockholm area.
The port authority, Stockholm Hamn identified the need for repairs to the quay wall and awarded a contract to remove damaged concrete to the specialist hydrodemolition contractor Waterjet Entreprenad. All the surface concrete cover of the main beams, crossbeams and underside of the quay, to a depth of approximately 30mm and with a strength of around 35MPa, needed to be removed to make way for the installation of cathodic protection.
Waterjet Entreprenad used a Conjet Robot 557 on the main and crossbeams, while a Conjet Nalta Jetframe 101 was used to treat the surface under the quay and beam sides. The Nalta was chosen as space under the quay was very limited and in some instances where the Nalta could not reach hand lancing was used.
Two high-pressure pumps supplied the water to the hydrodemolition units. For the Robot 557, Waterjet chose to use the 500kW Conjet super silenced pump rated at a pressure of 1040bar and flow rate of 262litre/min and for the Nalta 101 a 120kW pump rated at 2,600bar and flow of 24litre/min.