Damaged counterweight pulley bearing

• Causes

Corrosion to the counterweight pulley bearing can led it to be fractured

• Description of defect

Bearing balls will be detached from the bearing track causing the pulley shaft to lose support. Consequently, it will cause the pulley to tilt upwards and causing the arm of the pulley to deform.

Counterweight pulley will detach from its bracket the suspension ropes dislodged from the pulley.

Damaged counterweight pulley bearing [16]

• Diagnostic/testing method

Shock pulse meter shall be used periodically, measuring certain ultrasonic vibration produced within the bearing components. If there is sign of failure exist on the surface of the bearing, the nature of the ultra sound vibrations changes and the meter will indicate such changes. If the value of changes exceeds a certain empirical limit indicated by the manufacturer of the shock pulse meter, bearing replacement shall be conducted.

Bearing checker examination, using shock pulse method [31]

• Good practices

The active surface of the balls and roller of the bearing should be carefully examined visually by using a magnifying glass. If the bearing shows wearing signs such as excessive wear, chipping, spalling, cracks, pock marks, wash board marks, the bearings should be replaced as these signs indicate failure ultimately.

• Corrections

It is essential to install a good quality of bearings that free from any voids and impurities. This type of components need to be carefully manufactured, selected, installed, utilized and maintained, as faulty of bearing will fail the whole system, as they are functioned to attach the elevator components.