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shall furnish all necessary foundation bolts, plates, nuts, and <br /> washers for installation by the Contractor. Each foundation plate <br /> shall be '/2" thick Type 304 stainless steel. Foundation bolts, nuts, <br /> washers, and spare parts shall be Type 304 stainless steel. <br /> C. Stainless steel nameplates giving the name of the manufacturer, <br /> head, speed, and all other pertinent data shall be attached to each <br /> pump and motor. <br /> 10.08 PUMPS <br /> A. General <br /> 1. The pumps shall be totally submersible centrifugal pumps <br /> with close-coupled motors designed to pump sewage. The <br /> design shall be such that the pumping units shall be <br /> automatically connected to the discharge piping when <br /> lowered into place on the discharge connection. The <br /> pumps shall be easily removable for inspection or service, <br /> requiring no bolts, nuts or other fastenings to be removed <br /> for this purpose, or need for personnel to enter the pump <br /> well. Each pump shall be fitted with a 304 stainless steel <br /> lifting cable of adequate strength, and shall be five (5) feet <br /> longer than wet well depth to control panel to permit raising <br /> the pump for inspection and removal. <br /> 2. The impeller shall be constructed of nodular iron SP. The <br /> hydraulic design shall incorporate a single vane centrifugal <br /> impeller. The design shall permit low liquid velocities and <br /> gradual acceleration and change of flow direction of the <br /> pumped media. The impeller/casing design shall result in <br /> a passage free of surfaces to which solid or fibrous <br /> materials can adhere. The overall pump design shall <br /> combine high efficiency, low required NPSH, large ball <br /> passage and the ability to handle high solids <br /> concentrations efficiently. All other parts shall be of close <br /> grain gray iron construction, with all parts coming into <br /> contact with sewage protected by a coat of rubber-asphalt <br /> paint. All external bolts and nuts shall be of stainless steel. <br /> The impeller shall be of a centrifugal type, capable of <br /> passing 3-inch minimum diameter solids, fibrous material, <br /> and heavy sludge. If riser pipes are less than 3" in the wet <br /> well then the pumps must be grinder pumps. <br /> 3. Each pump shall be provided with a tandem double <br /> mechanical seal running in an oil reservoir, composed of <br /> two separate lapped face seals, each consisting of one <br /> stationary and one rotating tungsten-carbide or silicon <br /> carbide ring with each pair held in contact by a separate <br /> spring, so that the outside pressure assists spring <br /> compression in preventing the seal faces from opening. <br /> 10 -4 <br />