Mass production face broaching machines:They have rotary feed tables which permit loading/unloading of workpieces even when the machine is running.Even in a linear/continious broaching machine workpiece loading/unloading can be done while the machine is running.(Machine tools handbook:design and operation,P. H. Joshi,p:63)
Sliding Friction Thrust Bearings:These take the axial thrust along the face.Paralell or flat plate thrust bearings can be used for occasional or very light loads.Provision of a step increases the load capacity two to three times.However it is not suitable for bigger sizes as it is vulnerable to misalignment.Tapered land thrust bearing though costlier is more suitable for bigger sizes and heavier loads and must be properly aligned.Kingsbury thrust bearings which is even costlier uses a tilting pad.It can withstand a considerable degree of misalignment.Stepped tapered land and kingsbury thrusts are normally used with 0.14 kg/mm2 bearing pressure.The maximum pressure should not exceed 0.34 kg/mm2.(Machine tools hadbook:design and operation,P. H. Joshi,p:398)
Imbalanced rotor:Many applications can be modeled as a rigid body rotating about fixed axis. In particular driveshafts in automobiles and turbomachinery.If the rigid body is baanced than the axis of rotation corresponds to aprincipal axis of a rigid body.An imbalance is said to occur in situations where either or both of Ixy and/or Iyz are non zero.The şmbalance is common feature of wheel assemblies on cars and it is typically to add weights which usually range from 0.01kgs to 0.15kgs onto the rims of the wheels to reduce this imbalance.(Engineering Dynamics: A Primer,Oliver M. O'Reilly,p:189)
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