Sewage Pumps
EDDY Pump System NF-4000 for U.S. Navy:
Centrifugal discharge pumps installed in aircraft carrier sewage Collection, Holding, and Transfer (CHT) systems were experiencing a high rate of seal failures within a short time period after seal installation. A significant maintenance effort was required to replace the failed seals. In addition, the normal operation of these pumps resulted in the leakage of sewage material into the CHT pump room in violation of Navy health regulations. The total carrier fleet maintenance burden to overhaul the pumps and replace seals was estimated to cost the Navy about $750,000 per year. The Navy's PERA(CV) organization and Newport News Shipbuilding identified the EDDY Pump as being capable of meeting the zero external leakage health criteria and eliminating the problem of seal failures. EDDY Pump NF-4000 pump systems have been installed in several aircraft carriers in the fleet and are scheduled to replace existing CHT discharge pumps on all carriers. The NF-4000 pump system features a 5' intake and a 4' discharge, a 40 HP motor, and a combined electric and low pressure air supply controller. EDDY Pumps have been in service on aircraft carriers for several years. There has been no seal leakage or need to overhaul the pump systems. Seal cartridges on one carrier showed increased air flow and were replaced after 18 months of service. These replacements were attributed to a need for clarification of preventive maintenance greasing requirements. The simple design of the pump and the seal cartridge allows for easy service and maintenance if it should be required. Seal cartridges can be economically rebuilt providing further cost savings to the Navy. Ship's force have enjoyed the benefits of the zero leakage, low maintenance pump systems with cleaner CHT pump rooms and reduced exposure to sewage. The Navy is realizing significant improvements in CHT system reliability and a substantial reduction in fleet maintenance life cycle costs.
