In September 2016, AVK Armaturen delivered six double eccentric butterfly valves series 756 in dimensions DN1000 and DN800 for the supply line from the water reservoirs to the clean water pump stations of the Walddörfer Waterworks in Hamburg.
The AVK butterfly valves with stainless steel seat ring replace the originally installed butterfly valves from the 1980s. The replacement was necessary due to leakage of the old valves. The refurbishment took place during ongoing daily operation of the plant. Next to the butterfly valves four single-shut-off AVK hydrants series 35/31 were installed for the purpose of air release and intake during filling respectively drainage of the pipe system. The access to the valves and hydrants is granted by AVK plastic surface boxes series 80/30 and 80/31. Thanks to the mix of materials of the plastic body and cast iron lid, the risk of freezing and therefore blocking the lid is eliminated.
At the end of last year, AVK delivered five more double eccentric butterfly valves in DN800. The new butterfly valves replaced gate valves in short length from 1965 placed in the basement of the valve chamber, that is located between two reservoirs. The originally installed gate valves needed to be replaced due to wear. Two of the AVK butterfly valves are actuated by an electric actuator and three of them are manually operated.