Wear In Lubricated Journal Bearings

1978 ◽  
Vol 100 (1) ◽  
pp. 104-109 ◽  
Author(s):  
A. Begelinger ◽  
A. W. J. de Gee
Keyword(s):  
Journal Bearings ◽  
Polishing Process ◽  
Tin Alloys ◽  
Carburized Steel ◽  
Aluminium Copper ◽  
Lead Zinc ◽  
Steel Aisi ◽  
Copper Aluminum ◽  
Nonferrous Alloys ◽  
Copper Lead

If the combination of bearing material, lubricant, and journal material is well chosen, wear in lubricated journal bearings has a mildly abrasive character, the asperities of the journal surface slowly grinding away material of the inner surface of the bearing. It is shown that this process can be simulated adequately on a pin-and-ring apparatus. Experiments performed on such equipment show that the specific wear rate of bronzes, white metals, aluminum-tin alloys, copper-lead, zinc-aluminum and copper-aluminum increases linearly with increasing surface roughness of the mating component, i.e. a journal made from carburized steel AISI 5120 with a Vickers hardness of 680 · 107 N/m2. It is also shown that, when in contact under conditions of boundary lubrication with copper-tin, copper-aluminium, copper-lead, lead babbitt or tin babbitt the roughness asperities of the hard steel journal gradually disappear by a polishing process. This effect does not occur if the steel journal is in contact with either aluminium-tin or zinc-aluminium. The effect is tentatively explained in terms of an electrochemical interaction between the nonferrous alloys and the steel.

scholarly journals VII. Chemico-electric relations of metals in solutions of salts of potassium

1880 ◽  
Vol 30 (200-205) ◽  
pp. 38-49
Keyword(s):  
Thin Strip ◽  
Measuring Instrument ◽  
Magnesium Metal ◽  
Aluminium Copper ◽  
Gold Silver ◽  
Different Temperatures ◽  
Iron And Zinc ◽  
Particular Solution ◽  
High Degree ◽  
Copper Lead

The following experiments were made with the object of determining the chemico-electric positions of various metals, &c., in solutions of salts of potassium of various strengths, and at different temperatures; and also with the intention of ascertaining, by the aid of Lippmann’s- capillary electrometer, the quantitative differences of electromotive force between each two consecutive metals, and thus to construct a series of tables of electromotive forces of the particular solids and liquids employed. But as after making many attempts I was unable to construct such a form of that electrometer as might be relied upon as an accurate measuring instrument, I abandoned the object of measuring the electromotive differences, and proceeded no farther than simply determining the order of such differences in each particular solution. Although I have not been able to carry out the examination as far as I intended, I venture to submit the results to the Royal Society, in the hope that if published they may be of use to other investigators, as similar tables upon a less extensive scale have already proved. As the true electrical relations of metals in liquids depends largely upon the purity of the substances, I beg to state that the metals and salts employed were, in nearly all cases, the purest obtainable. The tellurium, mercury, and antimony were very highly purified by me ; the silicon was prepared by fusing some fine crystals, which I had previously digested with pure hydrofluoric acid, hydrochloric acid, and nitric acid separately. The gold, silver, platinum, palladium, iridium, rhodium, cobalt, tin, and cadmium, were obtained from Messrs. Matthey and Co., and were the purest they prepare. The nickel was refined by Sir J. Mason, and was of a high degree of purity; it had been rolled into a thin strip. The carbon was a rod of a Jablochkoff's candle. The indium was a portion of one of the ingots exhibited at the Paris Exhibition by its discoverers. The gallium was presented to me by M. Lecoq de Boisbaudran, and said to be "nearly pure except traces of zinc.” The thallium was supplied to me by Messrs. Hopkin and Williams. The magnesium was probably very pure, and was obtained from the Magnesium Metal Company, from whom I also obtained the bismuth, said to be “highly purified.” The aluminium, copper, lead, iron, and zinc wires were of the ordinary qualities.

Influence of Feeding Dehydrated Poultry Waste on Composition and Organoleptic Quality of Milk1

1977 ◽  
Vol 40 (1) ◽  
pp. 29-31 ◽  
Author(s):  
J. C. BRUHN ◽  
G. D. REIF ◽  
H. TOONE ◽  
J. H. EVANS
Keyword(s):  
Dairy Cows ◽  
Milk Quality ◽  
Poultry Waste ◽  
Quality Factors ◽  
Lactating Dairy Cows ◽  
Period 2 ◽  
Lead Zinc ◽  
Copper Lead ◽  
Composite Samples

A double reversal trial with three, 4-week periods was used to determine the effect on milk quality of feeding dehydrated poultry waste to lactating dairy cows. Fifteen cows were fed a control ration for 4 weeks (Period 1), followed by an experimental ration containing dehydrated poultry waste for 4 weeks (Period 2), and then by the control ration for 4 weeks (Period 3). Milk was collected daily and scored by five judges using the ADSA milk flavor scoring guide. Milk compsition (fat, protein, lactose, and solids-not-fat) was determined on alternate days. During Periods 2 and 3 weekly composite samples were collected to determine concentrations of cadmium, copper, lead, zinc, and tocopherol. No significant differences were found in any of the milk quality factors studied.

Distribution and significance of copper, lead, zinc and cadmium in the Corio Bay ecosystem

1981 ◽  
Vol 32 (2) ◽  
pp. 151 ◽  
Author(s):  
JD Smith ◽  
ECV Butler ◽  
BR Grant ◽  
GW Little ◽  
N Millis ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Nutrient Cycling ◽  
Mytilus Edulis ◽  
Water Exchange ◽  
Dry Weight ◽  
Weight Basis ◽  
Threshold Levels ◽  
Lead Zinc ◽  
Significant Interference ◽  
Copper Lead

Levels of copper, lead, zinc and cadmium in sediments, waters and mussels (Mytilus edulis) from Corio Bay (Vic.) were measured on two occasions in 1977. The bay has restricted water exchange with Port Phillip Bay and is known to have received a major input of cadmium. The respective concentrations of copper, lead, zinc and cadmium in the sediments were 2-50,2-2l0,4-398 and up to 12.6 �g/g; in the unfiltered waters, I .5-25, <0.4-11, 3.9-67 and 0.11-5.6 �g/l; and in the mussels, 4.8-21. 1.2-9.7, 105-110 and 9.8-53 �g/g on a dry weight basis. The observed levels of heavy metals are compared with threshold levels reported in the literature as causing significant interference with growth of phytoplankton and nutrient cycling by bacterial processes.

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