Mechanical Power Take-Off Units Duty Classification 5 #DriveLineHarmony CLASS I (Disconnect) 1. Pumps – centrifugal 2. Hydraulic pumps (without pre-charge) 3. Feeders – disc type 4. Agitators – pure liquids 5. Irrigation pumps. CLASS II (Light Duty) 1. Cookers – cereal 2. Elevators – bucket, uniformly loaded all types 3. Kettles – brew 4. Line shafts – light duty 5. Machines, general – all types with uniform loads, non-reversing 6. Bow thrusters 7. Generators (non-welding) CLASS III (Normal Duty) 1. Agitators – solid or semi-solids 2. Batchers – textile 3. Blowers and fans – centrifugal and lobe 4. Bottling machines 5. Compressors – all centrifugal, screw 5. Compressors – all centrifugal, screw 6. Elevators – bucket, non-uniformly loaded or fed 7. Feeders – apron, belt, screw or vane 8. Filling machines – can-type 9. Mixers – continuous 10. Pumps – two or more cylinders 11. Conveyors – uniformly loaded 12. Dredge pumps (allow for shock loading) 13. Locomotive railroad shuttles CLASS IV (Heavy Duty) 1. Cranes and hoists – working clutch 2. Crushers – ore and stone 3. Chippers – wood tub grinders* 4. Drums – barking* 5. Compressors – lobe rotary plus 3 or more cylinder reciprocating type 6. Haulers – car puller and barge-type 7. Machines – impact load types** 8. Mills – ball-type 9. Paper mill machinery – except calendars and driers 10. Presses – brick and clay 11. Mud pumps 12. Road planers CLASS V (Extreme Heavy Duty) DUTY CLASS V REQUIRES FACTORY REVIEW 1. Compressors – one and two cylinder reciprocating 2. Calenders and driers – paper mill 3. Mills – hammer-type 4. Shakers – reciprocating-type 5. Automobile shredders Duty Class I: The clutch is used for disconnecting the power from the load. When engaging, so little work is done that the clutch shows no temperature increase at the pressure plate outer surface. Use maximum input torque from the Class I Table, disregard kW. Themechanism is operated one or more hours before disconnecting. Examples: Engagement of clutches with the driven equipment having inertia less than that of the clutch and whose torque demand curve is similar to that of a centrifugal pump. Duty Class II: The clutch is used primarily for disconnect, but does more work during engagement than in Duty Class I. The clutch will engage within two seconds, never heat the pressure plate more than 28ºC* (50ºF)* above ambient, and once engaged is operated for one or more hours before disconnecting. The maximum horsepower which the clutch can absorb is given in Class II Table. Examples: Power shovel master clutches, generators, line shafts and similar light-duty drives. Duty Class III: The clutch will engage within three seconds, never heat the pressure plate more than 56ºC* (100ºF)* above ambient, and once engaged is operated for one or more hours before disconnecting. The maximum power which the clutch can absorb is given in Class III Table. Examples: Engine PTO starting average loads, and clutches whose starting load is up to 1.4 times the running load. Blowers, fans, screw compressors, conveyors and similar normal-duty drives. Duty Class IV: The clutch will engage within four seconds, never heat the pressure plate more than 83ºC* (150ºF)* above ambient, and once engaged is operated for one or more hours before disconnecting. The maximum power which the clutch can absorb is given in Class IV Table. Examples: Engine PTO starting heavy loads such as rock crushers, mud pumps, and other large inertia machinery and clutches whose starting load is up to 1.8 times the running load typical of heavy-duty drives. Duty Class V: The clutch is used to start large inertia loads which require four seconds to start the largest load, with the longest slip period per engagement not to exceed ten seconds. The clutch must be selected according to its horsepower absorption capability. Clutch applications in this Duty Class, or those which require frequent engagements, require factory review. Contact jbj Techniques technical office, telephone: +44 (0)1737 767493 or email: info@jbj.co.uk for consultation on the drive. For reciprocal compressors and applications where high torsion can be experienced, a flexible coupling should be mounted between clutch and flywheel. * Dt (temperature difference). ** Beware of operator misuse. www.jbj.co.uk/mechanical-power-conversion.html
RkJQdWJsaXNoZXIy NzQyNjQ=