Sulfated Residue, Lead, Iron and Copper in Lubricating Oils

In this  methods, the sample  is completely  oxidized  by wet  ashing  with  concentrated  sulfuric acid, concentrated  nitric  acid and  hydrogen  peroxide, or  if  only iron and copper  are  to be  determined, by dry  ashing. To determine sulfated  residue, the  solution obtained by  wet  ashing  is  transferred  to a weighed  dish, evaporated  to  dryness, ignited at 775 degree C, cooled and  weighed. In determining lead, iron and  copper, the  solution resulting  from  the  wet  ashing is  mixed with  alcohol and  filtered  to give  a  precipitate  of  primarily  and  sulfate. This  precipitate  is  boiled  with  sodium carbonate and  then  precipitated  with  hydrogen  sulfide.

Iron  and  copper are  determined on  separate  aliquots  of the  filtrate  from  wet  ashing. The  iron is  separated  as the  hydroxide and  determined colorimetrically  as the  orange  ferrous  orthophenanthroline  complex,  while  copper  is  determined  colorimetrically  as the  yellow diethyldithiocarbamate  complex

Automatic Transmission Fluid proving Ground Tests

Satisfactory operation of such  fluid is  observed  during  a 2000 mile  schedule  on proving  Ground Automatic   Transmission  Performance Test  Schedule. This requires a new or rebuilt Hydro Matic transmission   in stalled in a car. Characteristics of the fluid, such as viscosity at 200 degree F before and after the test are observed. Tendency to squawk is noted and also smoothness of operation.

Turbine oils for Automotive Vehicles

Since  gas  turbine  engines  for  automobiles  have  a  potential  which  no  doubt will  soon  be  realized,  mention will  be  made  of the  lubricant  requirements  for  the  drives. The oil will be used to lubricate both bearings and gearing. The  bulk oil  temperature will  probably  be at least  300 degree F during  operation, but  the oil will  not  be  subjected   to hot combustion gases  and thus should remain    comparatively   clean.

Whether   the oils  used will preferably  be  petroleum or  synthetic or  blends  of  the  two  is a  question. Whatever type, they will   no doubt contain various additives, such as   antifoam    agents, oxidation inhibitors, metal deactivators, and antiwear agents.

Speculation as  to  consumption  and  renewal  of  such  oils   indicates that  the oil  reservoir  will  have  a capacity  of about  3 quarts  and that  the   consumption will be  almost  nil  but  that  an  oil  change  yearly  can be  expected.

Transmission and Axle lubrication

Since  the  lubrication of  transmissions  and axles  is  of  primary  importance  in  automotive vehicles, as gearing  is  concerned, this subject  will have first  consideration.  Mention of the lubrication of other gear sets in such vehicles   will then follow:

Also the major discussion will consider internal combustion engines as a source of power. Other  sources  of power  and methods other  than  gearing  for  driving  vehicles and the    consequent fluids  require  will also  receive  mention. Gearing  or  transmission  mechanisms  of automobiles, buses or  trucks  are  lubricated, in the  main , by  bath  or  splash  systems  with some   use of  forced  feed. The gear  cases are  generally  as small  as  possible  so that  consequently  the amount  of gear  oil  present  is  restricted. While  the fluids  present  in gear  boxes  may have  other uses, the primary  functions  are  to  prevent  wear  of gears  and to  act  as a  heat  transfer   medium. The  general  subject of wear  prevention  has been  discussed  previously  and  may  be  due  either  to  the  oil film  alone  or to  this fluid  supplemented by EP  films. The  oil  in gear  cases  of  vehicles takes  up heat  from  the  moving  gears  and transfers  it to the  inside  of the casing. Form here it is dissipated to the surrounding air. Such  radiation is not  always  what  is  desired  because  the gear  housing  becomes  coated  with  dust  or  dirt. Consequently, particularly  in  heavy  trucks  and  busses, the  temperature of the  lubricant may  reach  250  to 300  degree F  causing  excessive oil  deterioration.

 The  loads, speeds,  conditions of use and the  operators  of  vehicles  vary  so  widely  that  it is a wonder  that  automotive  gears  give such  long  and  trouble  free  operation as they  do in  most cases. The service  obtained  from such  gearing is  probably more of a  tribute  to the people who  formulated and  supplied   the  lubricants than  to the  designers  of  the  mechanisms. In fact Raymond, a few years  ago, stated: “ The  hypoid  axle  is easily  the hardest  working  and possibly  one  of the most  neglected   automotive  components”. Elsewhere  the  thought  was  advanced that gear  oil  manufacturers have been  asked to  perform  miracles, in order to lubricates  such  gears.

  

Power Steering Gear Fluids

As a base for such a fluids, a solvent refined oil of about 250 viscosity SUS at 100 degree F may be used. While , as Johnson and Mortensen state, the major requirements are shear  stability  and high  V.I., the oil should  also  be  resistant  to oxidation and  have no  adverse effects on both metals  and  seal and  hose  materials. Likewise the blended oil should have a low pour point. All of the above point to a solvent refined oil which will have the desired high V.I. and aniline number.

Chrysler MS 3590 “Hydraulic Steering Fluid with Rust Preventive”, summarizes the composition requirements as follows:

“Well refined oil with admixture of proper rust preventive additives. Small amounts of oxidation inhibitor and pour depressant may also be used to meet the details requirements. The use of   detergents and V.I. improvers is prohibited. The additives small be selected to have a minimum effect on the seal and hose materials”.

Therefore, additives may  include up to 0.5 per cent  of an  oxidation inhibitor, such as  can be  recommended  by  an  additive supplier, or  may  be  phenyl  alpha napththylamine , 2,6-ditertbutyl – 4- methyl  phenol, mixtures  of these  two  types, or  an oil-soluble  organic thiophosphate salt of certain  metals, such  as zinc  methylphenyl  dithiophosphate.

If the pour point of the oil is above -20 degree F, from 0.2 to 1 per cent of a pour depressant, such as “Acryloid  150”, “Paraflow”, or “ Santopour C”, can be added.

Suitable rust inhibitors, used in concentrations of 0.5 to 2 per cent, include petroleum or synthetic sulfonates, such as “Petronate” or barium dinonyl naphthalene sulfonate. A combination oxidation and rust inhibitor, which is usually used in a concentration of 1 per cent or less, is “Vanlube 76”. 

Diesel Locomotives –tractions Gear-Lubrication

Most traction gears on diesel locomotives are lubricated with high viscosity, adhesive gear oils. Residuum  type products  with  viscosities    as  high  as 500 Furol  at  210 degree F    have  been  used, but  in most  cases  a viscosity  of  2000 SUS at 210 degree F is  satisfactory. About  fifteen  pounds is  required  for an  initial  fill  and  since there  is  some  leakage,  the  gear  case  should  be  checked and refilled at  least  every  month. U.S. specification MIL-L-13914 (ORD) provides for two  grades of such oil, one  with  a viscosity  of 170 to 240  Say bolt  Furol  at 210 degree F and  the other  with a similar  viscosity of  480 to 580. A lubricating  greases is  recommended for the  purpose by  Morway  and  Ball^38  in which  the  thickener  is a  complex  sodium  soap  and the fluid is a mixture of  14.93 parts of a  low  cold  test oil  having  a  viscosity of 55  SUS at  210 degree F  and 75 parts of a  resin  from a Pennsylvania  oil  having a  viscosity  of  14,000 SUS at  210 degree F. When  such a  lubricant was used  in a  locomotive  in  freight  service  it did  not  leak  from  the gear  case, and  after  one  year  of  service there  was  only  slight  wear  on the  pinion  and driving  gear  teeth. 

Carbonated Beverages and Gears

In preparing   beverages, gears are often used on meters to synchronize delivery of syrup and water to carbo coolers. Also on automatic   bottle cleaners, gears are used to rotate brushes both on the inside and outside of the bottle. These latter gears are often flooded with the detergent   solution used in washing and other lubrication is not permitted.

Conveyors, in such  establishments, when  driven  by  reduction gears,  can be  serviced  by  an  oil  of about  500  viscosity SUS at 100 degree F, if enclosed, or a residual  type  of about  2000 SUS at 210 degree F, if of the open  type.

Candy Manufacture and Gears

The method  of mixing  batches  of candy  will  vary  depending  upon  both  the  size  of the lots  and the  stiffness. Cake mixers may be used in some cases. In other instances, rollers, gear driven, will be used. Thus, either enclosed or open gears may be encountered. In  the  former case, the  gear  oil  can be  of about  500 viscosity  SUS  at 100 degree F, and in the  latter case  about  2000 SUS at 210 degree F.

Dripfeed Gear Lubrication

Dripfeed application of gear oils may be considered semi-automatic in that it is adjustable to a certain degree. The feed for the oil in this case may be by gravity or even by circulation if the stream in the latter instance can be throttled down sufficiently. In the first case a container can be filled by hand or even a small drum can be connected with piping ending in a valve or cock to permit adjustment of the feed. Here, as the amount of oil in the container becomes less, the feed will decrease. Where such a feed is partly mechanical, the oil will come either from a storage tank to which a pump has delivered it or directly from a circulating line. In either case the amount of used can be calibrated.

While dripfeed can be applied to enclosed gearing it is more often used on open gearing. Here it is applicable to softer types of gear oils including cut back types. This is more desirable method of lubricating open gears than the methods previously mentioned. Also, in case cut back gear oil is used, any vapor from the same will escape slowly and hence will be less of a hazard than if the mixture were sprayed on. Further, there are fewer tendencies to over lubricate by a drip method than with other methods of hand application. Therefore, there is a consequent reduction in waste and poor housekeeping.