Shaft Couplings - Cross & Morse - #2

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2 Coupling Power Range Speed Range Shaft Size Max. Angular Max. Parallel Max. Torsional Type kw rpm mm Misalignment Misalignment mm End Float mm Stiffness Heavy Shock - 8 hr./day Blowers (centrifugal), Compressors (reciprocating), Crushers, Feeders, 2.5 2.8 3.2 Reversing under full load Hammer Mills, Hog Drives, Presses, Pumps (reciprocating, oil well), High Starting torque Tractors, Trucks, Winches Uneven load - 8 hr./day Beaters, Cranes, Compressors (centrifugal), Elevators (bucket), 1.5 2 2.5 Moderate shock or torque Grinders (pulp), Hoists, Kilns, Mills (ball, rolling, pebble, tube), Non-reversing Mixers, Rotary Drills, Speed Reducers, Woodworking Machines Gasoline or Diesel Gasoline or Diesel Driven Mechanism Engine 6 or more Engine 6 or less Characteristics Cylinders Cylinders Typical Electric Motor or Steam Turbine Coupling Selection There are four basic functions which a shaft flexible coupling may be required to accommodate, and selection of a coupling should be made considering these. Angular Misalignment Occurs when shaft axis are inclined to one another. End Float The ability to accommodate axial displacement of shafts due to thermal expansion or motor end float. Torsional Stiffness The ability to absorb torsional impulse loads. Rubber coupling stiffness can be adjusted to damp out vibrations. Metal couplings generally transmit torque without angular displacement. Parallel Misalignment Present when axis of shafts are parallel but laterally displaced. Generally flexible couplings are required to accommodate a combination of the basic functions, and selection is made on ability to exceed the anticipated types of misalignment. Cross & Morse Couplings have the following basic capacities. Delrin Chain 45 100- 5000 10- 60 1° 0.20 2.0 Stiff Roller Chain 925 0- 2000 10-150 1° 0.76 – Stiff ‘L’ Series 270 500-31000 3- 60 1° 0.40 1.0 Flexible KE Series 760 50- 7700 8-130 1° 0.50 1.7 Flexible GE Series 360 100-14000 8- 90 11/2° 1.80 2.4 Flexible Morflex Cplgs 600 100- 6500 10- 80 5° 1.25 1.0 Very Flexible Polymer Gear Cplgs 170 0-14000 6- 65 2° 1.30 2.0 Stiff Steel Gear Cplgs 3200 0- 6000 8-175 1° 0.80 2.0 Very Stiff Selection Procedure for Chain and Rubber Couplings (Gear Couplings refer to Page 13). Selection of correct type and size of coupling is essential to realise a long service life. Outside forces acting on the coupling and its own performance limitations must be taken into consideration in making a selection. 1. Assemble data required to select coupling. Type of driver and driven equipment. Shaft size of driver and driven. Load to be transmitted (kW, rpm). Space limitations. Misalignment - Angular, Parallel, Endfloat. Hours of operation/day. Lubrication facilities. Environment (temp., corrosion, etc.). 2. By consideration of the misalignment, power and speed requirements, select a Coupling Series from the table above. If gear coupling, see also page 13 for selection procedure. 3. Determine suitable service factor from table below and modify for daily usage time. Less 4 hrs/day -0.1 16 hrs/day +0.2 24 hrs/day +0.3 4. Determine design power kW using factor obtained Pd. kW=kW x S.F. (f1) 5. Using the design kW power value, select the correct coupling from the power rating tables for the respective series. Check coupling chosen will accommodate shafts, if not select larger size to meet shaft requirements. Ensure coupling finally selected can meet speed requirements, and space limitations. Even load - 8 hr./day Agitators, Conveyors (chain or belt) 1 1.5 2 Non-reversing - Elevators, Evaporators, Generators, Line Shafts, low starting torque Screens, Centrifugal Pumps & Fans Te l : + 4 4 1 2 1 3 6 0 0 1 5 5 F a x : + 4 4 1 2 1 3 2 5 1 0 7 9 E m a i l : s a l e s@c r o s s m o r s e . c o m INDEX BACK NEXT