Malfunctioning of Other Mechanical Elements

Misalignment may be due to wear of bearings and in extreme cases of failures it may be difficult to determine whether a bearing or a gear failed first. In case of bearing failures, when lubrication was at fault, either oil did not get to the bearing. Or the proper oil was not used. Where  a common  oil is used for bearings and gearing, the  viscosity of the oil is  generally  a compromise  since  the bearings operate best with  a lower  viscosity oil than  is dictated for the gear sets. Therefore, when bearing trouble is encountered, thought might be given to use of a somewhat lower viscosity lubricant.

Malfunctioning of flexible couplings may also contribute to trouble with gear sets. Such couplings are often used to connect reduction gears with a different piece of apparatus. These  couplings may not only  break but  also  become  jammed, so that  they  are no longer flexible; thus the  gear  shaft will  be thrown out of line. Another possible source of trouble might be a break in a gear case or supports which would permit a shaft carrying gears to be misaligned.

Pour Point Depressants

Certain  polymers when  added to wax containing lubricating oils in  proportions of 0.1 to 5 per  cent, will  alter  the  crystal  structure  of the  wax  and  thus  permit  movement  of the  oil  at a much  lower  temperature  than  before  the addition. Some  agents  used  for  other  purposes, for  example V.I. improvers, may  have a similar  influence on  pour  points.

Most  industrial  gear  oils do not  require  this  type  of  additive but  pour  depressants are  often  included in  automotive  gear  lubricants. The agents  normally  used  include  “Acryloids”  which  are  methacrylate  polymers,  and  “Paraflow”  or “ Santopour”  which  are  wax condensation  products with either  naphthalene or  phenol.