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Brass or stainless steel nameplates giving the name of the manufacturer, the rated capacity, head, speed, serial number, model number, horsepower, voltage, amperes and all other pertinent data shall be permanently affixed to the pump. The complete pump and motor assembly shall be capable of being fully submerged to 65 feet without leaking. 2.02 Grinder The Grinder shall be placed immediately below the pump stator and shall consist of a stationary, shredder ring and a cutter impeller. Materials of construction for the grinding components shall be high chrome, hardened, stainless steel throughout the components. Components that are surface hardened or not stainless steel will not be considered equal due to their lack of wear resistance. For ease of service, the grinding impeller shall be securely fastened to the pump shaft by means of an allen screw. 2.03 Mechanical Seals Each grinder pump shall be provided with a tandem mechanical shaft seal system consisting of two totally independent seal assemblies. The seals shall operate in a lubricant reservoir filled with food grade oil, that hydro dynamically lubricates the lapped seal faces at a constant rate. The lower, primary seal unit,located between the pump and the lubricant chamber, shall contain one stationary ceramic seal ring and one positively driven rotating, corrosion resistant tungsten carbide ring. The upper, secondary seal unit, located between the lubricant chamber and the motor housing, shall contain one stationary ceramic seal ring and one positively driven rotating carbon seal ring. Each seal interface shall be held in contact by its own spring system. The seals shall require neither maintenance nor adjustment nor depend on direction of rotation for sealing. The position of both mechanical seals shall depend on the shaft. Mounting of the lower mechanical seal on the impeller hub will not be acceptable. The use of a single mechanical seal, lubricated by the only the pump media will not be considered equal. 2.04 Bearings The pump shaft shall rotate on two bearings. Motor bearings shall be permanently grease lubricated with high temperature grease. The upper bearings shall be single row ball bearings and lower bearings shall be double row ball bearings. Sleeve bearings do not provide adequate alignment and will not be acceptable. Bearings shall be rated for 50,000 hours of use for maintenance free performance. 2.05 Electric motor The pump motor shall be induction type with a squirrel cage rotor, shell type design, housed in an air filled, watertight chamber, NEMA B type. The motor shall have low starting amperes not exceeding 30 and high starting torque of at least 8.4 foot pounds. The stator windings and stator leads shall be insulated with moisture resistant Class F insulation rated for 155 C (3 11 F). The motor stator shall be insulated by the trickle impregnation method using Class F monomer-free polyester resin resulting in a winding fill factor of at least 95% and shall be heat-shrink fitted into the stator housing. Dip and Bake motor insulation method with less than 70%fill rate is not acceptable due to increased air gaps and shortened motor life. The use of bolts, pins or other fastening devices requiring penetration of the stator housing is not acceptable. The Electric Motor 3