Gear damage

In the case of bearing or gearing damage or where the impeller saapes the... 

Visual inspection of gears provides a positive means to isolate the potential root cause of gear damage or failures. The wear pattern or deformation of gear teeth provides clues as to the most likely forcing function or cause. The following sections discuss the clues that can be obtained from visual Inspection. 

The gear unit must be tuned to the system in which it operates. Die vendor with the train responsibility must analyze the system to be certain the gear unit will not transmit torsional or lateral vibrations to the rest o the system or be damaged by system excitations. 

Some vertical drain lines in a building were no longer needed, so they were disconnected and capped but left connected to the horizontal main drain below. The caps were fixed with tape but were not made watertight as there was no way. it seemed, that water could get into them. Fifteen years later a choke developed in the main drain, water backed up into the disused legs and dripped into an electrical switch box. All power was lost, and some of the switch gear was damaged beyond repair [23]. 

The proper size of shaft is very important to avoid whip and vibration, destruction of bearings, gears, and damage... 

Smaller rotary positive displacement compressors are controlled with external bypass. Such equipment usually has a built-in relief valve that opens at a pressure short of damaging the equipment, but the external bypass still is necessary for smooth control. Large units may be equipped with turbine or gas engine drives which are speed adjustable. Variable speed gear boxes or belt drives are not satisfactory. Variable speed dc motors also are not useful as compressor drives. Magnetic clutches and hydraulic couplings are used. 

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