AVK-UK & Wouter Witzel ersetzen 16 Absperrklappen DN800 & DN900 für Abwasseraufbereitung in der Nähe von Liverpool, Großbritannien
Birkenhead Waste Water Treatment Works is part of United Utilities’ Lower Mersey Project which is built in the 90’s to ensure that the effluent discharges satisfy the European UWW Directive. Refurbishment of part of the plant started in late summer of 2015, which consisted of the replacement of 16 DN800 and DN900 butterfly valves which were originally installed in 2006.
Due to leakage problems and valve issues beginning 2015 constructing company Nomenca Ltd. were asked to carry out a pipeline video inspection, this revealed more substantial issues with the existing competitor butterfly valves than first thought. As seen on the images it was obvious that not only all the old valves where leaking, but for one valve the whole valve-disc had separated from the valve body and was found over 2 metres into the pipework. The pre-filtered sewage water corroded the stainless steel discs and shafts so much that it destroyed the valves completely within 10 years.
Due to the good performance of other AVK products on site, United Utilities asked AVK to replace the old valves with Wouter Witzel centric vulcanised bonded to body butterfly valves. Advantages as the protected valve body, the dry shaft design and reliable operating torques where decisive for their choice. Good cooperation between AVK UK and Wouter Witzel resulted in an order for 9 No DN800 and 7 No DN900 EVUS valves with EPDM bonded to body liner and Duplex discs. Next to the valves, also the extensions and electrical actuators where included.
October 2015 all the valves where replaced in a one week plant shutdown period at the treatment works, which serves a population equivalent to 220,000 people, to ensure that the facility is updated to function properly for the coming decades…for sure the butterfly valves certainly will…!