MECHANICAL SPECIFICATIONS FOR XT SERIES TOP ENTRY MIXERS
The mixer assembly shall consist of a horizontal NEMA C-face motor, a right angle single reduction speed reducer, mounting base, impeller shaft and impeller(s).
1.0 - Agitator Drive Design Each drive assembly shall consist of a heavy duty right angle speed reducer with cast iron housing and covers. The reducer will be fitted with a NEMA C-face adapter for horizontal mounting of a direct or flexibly connected electric motor. Speed reduction shall be by means of a single stage worm drive. The wormgear shall be AGMA Class 8 chill cast bronze mounted on a splined shaft. The wormshaft shall be cut, carbonized, finish ground and polished. The reducer shall be designed in accordance with AGMA 440 standards. The output shaft shall have a keyway and locking collar for installation of the impeller shaft while insuring accurate alignment and ease of removal in the field.
2.0 - Reducer Rating Reducer shall be rated in accordance with the appropriate AGMA standards with a minimum service factor of 1.50, based on motor nameplate horsepower. Thermal ratings shall exceed the motor nameplate rating. Bearing ratings shall be based on a minimum L10 life of 20,000 hours at a service factor of 1.50, 50,000 hours at a service factor of 2.00, and 100,000 hours at a service factor of 2.50, under worst conditions of loading.
3.0 - Bearings High speed bearings shall be ball bearings. Low speed bearings on the oversized quill shaft shall be tapered roller bearings.
4.0 - Lubrication Gears and high speed bearings shall be splash or dip lubricated. A drywell around the output shaft shall prevent oil leakage. Low speed bearings shall be grease lubricated. All grease fittings ,oil fill and drain ports shall be easily accessible.
5.0 - Shaft Design Agitator shaft stresses, considering combined torsional and bending loads, shall not exceed 6,000 psi. Non-stabilized shafts shall operate at less than 60% of first critical speed. Stabilized shafts shall operate at less than 80% of first critical speed. The shaft shall be of the specified grade of carbon or stainless steel. All points of support and impeller connection areas shall be concentric to within 0.010" tin
6.0 - Impeller Design Mixing impellers shall be of the high efficiency hydrofoil design, or as specified. The blades shall be bolted to a center hub which shall be keyed to the mixer shaft. If coated, the blades and center hub shall be welded. The impeller(s) shall be of the specified grade of carbon or stainless steel. Shaft keyway for vertical adjustment of impellers shall be provided as specified.
7.0 - Motors Electric motors shall be constant speed, 1800 or 1200 rpm, and suitable for operation on 230/460 volt, 3 phase, 60 Hertz alternating current, or as specified. The motor shall be TEFC squirrel cage induction type built in accordance with current NEMA design B standards with Class B or F insulation, and C-face mounting.
8.0 - Manufacturer Mixer shall be Series XT as manufactured by EMI / Cleveland Mixers, Clinton, CT.