Evaluation method for thermal-oxidative stability of lubricants
(57) Abstract:The invention relates to the field of study of lubricants used in the pressure treatment. Evaluation method for thermal-oxidative stability of lubricants includes heating the sample to a predetermined temperature in a porcelain crucible, determination of mass fraction of volatile and insoluble substances, with a mass fraction of volatile substances is determined by weighing the crucible before and after heating, and then the mass fraction of insoluble substances is determined on the walls and bottom of the crucible when it is weighed after removing them from the sample to obtain the insoluble residue. Improved reliability of estimation of the oxidative stability of lubricants due to the simultaneous determination of mass fraction of volatile and insoluble substances after heating the sample at a given temperature, and the ability to predict the contamination of the metal surface during the pressure treatment. table 1. The invention relates to the field of study of lubricants and can be used in rolling mills for predicting the contamination of cold-rolled metal.There is a method of assessing € RF N 2098812, CL G 01 N 33/30, publ. 10.12.97 bull. N 34). However, this method does not allow to evaluate the resistance of the oil to oxidation.Known photometric method of assessing oxidative stability of lubricants (Kowalski B. I., Nazarov, G.: laboratory 1997. So 63. N 12 C. 16-17). The disadvantage of this method is the lack of quantitative measurement of thermostability.The closest in technical essence to the present invention is a method of assessing oxidative stability of lubricants by determining mass fraction of volatile and insoluble substances (Turcan, I., Kuznetsov, C. P., Gvirtzman A. A. Lubricating and protective materials, M.: Transport, 1981, S. 47-48). However, this method does not allow to model the degree of contamination of the metal surface during the pressure treatment.The technical task to be solved by the invention, is to increase the reliability evaluation of oxidative stability of lubricants.This is achieved by simultaneously determined by the mass fraction of volatile and insoluble substances after heating the sample at a given temperature.The method zakluchaetsa), which weighed on an analytical balance from 1.0 to 1.5 g of a lubricant.The crucible is placed in a heat chamber, heated to a predetermined temperature, and maintain it 60-120 minutes After cooling, the crucible is weighed and determine the mass fraction of volatile substances. Then the rest of emulsol is drained, washed with crucible gasoline, it is dried in a heating Cabinet at 100oC to constant mass and calculate the mass fraction of insoluble substances formed on the sidewalls and bottom of the crucible, when it is weighed after removing them from the sample to obtain the insoluble residue.To test the effectiveness of the proposed method was evaluated oxidative stability of various lubricants used in cold rolling of metal on pjatikletevoj mill "2030" JSC "NLMK" in Lipetsk). Was previously calculated average temperature in the deformation zone for this mill, which was 240oC. At this temperature and were tested lubricants. The results are given in the table.From the data presented in the table it follows that the proposed method for 60-120 min allows to differentiate on the oxidative stability of different is the most pure metal was obtained using lubrication Quakerol 671 N", and the most dirty - lubrication "Renol-1". Evaluation method for thermal-oxidative stability of lubricants, including heating the sample to a predetermined temperature, determining mass fraction of volatile and insoluble substances, characterized in that the heating of the sample to a predetermined temperature is carried out in a porcelain crucible, and the mass fraction of volatile substances is determined by weighing the crucible before and after heating, and then the mass fraction of insoluble substances is determined on the walls and bottom of the crucible when it is weighed after removing them from the sample to obtain the insoluble residue.
FIELD: any industries where motor oils are used.
SUBSTANCE: proposed device contains shaped insert with oxidizer feed axial channel. Ring passage space for cooling agent is found inside shaped insert, and outer surface of middle stage is provided with corrugations. It provides cooling of oil vapors settled on corrugations at heating and dripping down in form of condensate into high temperature oxidation zone. Oil sample meter is provided in lower part of cylindrical head made in form of branch pipe by means of which metered delivery of oil to surface of aluminum weighing bottle is carried out. Oil is applied in layers, each being 150±5 mcm thick, each layer is oxidized, 240±5 s, by delivering oxidizer at rate of 50 l/h directly to surface of oil layer in aluminum weighing bottle. Taken as information index is mass "m" on deposits formed on aluminum weighing bottle. At mass of ratios greater than or equal to 0.0170 g (m≥0.0170g) oil is considered as group "В" oil, and ratio 0.0130g≤m<0.0170g oil is considered as group "Г" and at m<0.0130g, oil is considered as group "Д".
EFFECT: improved accuracy and reduced time taken for determining service group of motor oil under investigation owing to provision of conditions of testing close to real conditions of operation of oil in engine.
3 cl, 2 tbl, 1 dwg
FIELD: express-methods for determining presence and quality of dispersing-stabilizing properties, dispersing agent type for lubricating oils and determining engine oils among other oil types.
SUBSTANCE: method for determining dispersing-stabilizing properties of lubricating oils is performed by inserting into oil and dispersing therein of dirt agent and reaching calm state, while liquid dirt agent is injected into oil, which does not form a solution with oil, and after dispersion, emulsion is maintained in calm state, on basis of alternation of information parameters like loss of transparence and coloring of emulsion in colors from dark yellow to light yellow, quality estimate of presence of dispersion-stabilizing properties is determined with detection of engine oils, and on basis of alternation of information parameters like in form of intensiveness of coloring of emulsion in colors ranging from dark yellow to light yellow, time when dirt agent starts precipitating and/or time when emulsion starts dividing on distinct layers or absence of same, volume of precipitated dirt agent and/or height of column of layered emulsion during certain time limit or absence of same, volume of dirt agent inserted into oil, for which precipitation of dirt agent starts or layering of emulsion, and also - possible combination of same, quality estimate of workability level of dispersing-stabilizing admixture of lubricating oil is determined, as well as dispersant type.
EFFECT: decreased time consumption, increased information capacity of determination.
FIELD: analytical methods.
SUBSTANCE: invention is intended for use as a means of metrologically supporting measurement techniques in determination of total alkaline number of motor oils and lubricating materials. This means is represented by composition containing 75-84% liquid hydrocarbons, 0.05-6% water-soluble alkali component, and 15-20% aliphatic alcohol. Use of standard specimen allows performing reliable estimation of quality of motor oils and lubricating materials by accessible acid-base titration technique requiring no special instrumentation equipment.
EFFECT: simplified analytical procedure.
FIELD: investigating or analyzing materials.
SUBSTANCE: method comprises heating, mixing, aerating and degassing of lubricant in the device for investigating the lubricants. The aerating of the lubricants is provided by their flowing through the opening of alternative cross-section where pressure drop is generated. The degassing is provided by the use of the degassing unit where, under the action of centrifugal forces, the dissolved gas is removed from the lubricant. The processes are controlled by video surveying of generation, change of sizes, shape, and concentration of gas bubbles in the lubricant as well as by readings of temperature and pressure gauges. The device comprises oil tank for temperature control with mechanical mixer, heater, and temperature gauge and pipeline with valve. The device is additionally provided with pump, throttling valve, and degassing unit. The safety valve, pump, and throttling valve are connected in series through pipeline sections. The pipeline sections provided with throttling valve and degassing unit are made of a heat-resistant transparent material and provided with temperature and pressure gauges and digital video cameras connected with the computer.
EFFECT: enhanced precision.
2 cl, 1 dwg
FIELD: technology for diagnosing status of motor oil, possible use for determining quality of motor oil during operation and its fitness for further use.
SUBSTANCE: in accordance to method for determining content of liquid in motor oil, motor oil is heated up and by intensiveness of characteristic air bubbles, presence of liquid is evaluated, while firstly a template made of wire in form of mesh is applied to crucible of Cleveland machine, heated up with heating speed 6°C per 1 min up to 100°C, in range of temperatures 120-140°C heating is decreased down to 2°C per 1 minute, then position of cells in contour, formed by air bubbles in template, is visually memorized, further, contour is transferred over a squared paper, by squares, value of area of contour surface is calculated by its value, percentage of liquid is determined using standard depending on base for motor oil.
EFFECT: increased precision of detection of presence of cooling liquid in oils and its percentage.
3 tbl, 2 dwg
FIELD: investigating or analyzing materials.
SUBSTANCE: method comprises preparing a mixture of oil to be tested with a standard oil, in mass%, 90:10, 50:50, and 10:90, sampling each mixture, allowing the samples to stand at a high temperature of 125±2°C for 24 hours, cooling the samples down to the room temperature with subsequent allowing the samples to stand at a low temperature for 8 hours, allowing the samples to stand at the room temperature for 240 hours, and performing the visual assessment of physical condition of the samples after each stage.
EFFECT: enhanced reliability.
3 ex, 7 tbl
FIELD: car industry; aircraft industry; other industries; methods of determination of the dispersion-stabilizing properties and pollution of the working oils.
SUBSTANCE: the invention is pertaining to the express method of determination of dispersion-stabilizing properties and pollution of the working oils. The method of determination of the dispersion-stabilizing properties and pollution of the working lubricating oils is realized by application on the filtering paper of the drip of the tested oil. After expiration of the preset time determine dimensions of the concentric zones the received chromatogram, and in compliance of their ratio judge about the functionability of the additive compound with the help of the formula. For each type of the oils (diesel, petrol or others) at first determine the temperature at which the additive compound demonstrates its maximum activity, and then this thermal regime use for obtaining of the chromatogram from the first drip descending from the drip-former on the filtering paper in the stationary and field conditions. The composition of the mechanical impurities in the test oil is determined in compliance with the core of the chromatogram using the magnifier of the image by separation of the really present in the oil of the different types of the pollutants and, thus, generalizing the outcomes of the evaluations of each type of the impurities present in the oil determine the composition of the impurities and the total pollution of the lubricating oil. The invention allows to receive the high accuracy of the evaluation both in the field and stationary conditions of the real activity of the disperse-stabilizing additive, and also - of the composition and concentration of the mechanical impurities in- the working lubricating oils-.
EFFECT: the invention allows to receive the high accuracy of the evaluation both in the field and stationary conditions of the real activity of the disperse-stabilizing additive, and also - on the composition and concentration of the mechanical impurities in- the working lubricating oils-.
2 tbl, 2 dwg
FIELD: mining industry, possible use for predicting tribotechnical properties of lubricating materials for drill bit supports at the stage of laboratory testing.
SUBSTANCE: in the method for testing lubricating materials, destruction activation energy of metallic surface before and after application of lubricating material is estimated and difference ΔG of produced activation energy values is determined. Tests of lubricating materials are conducted in range of temperatures matching operational temperatures. Type and the degree to which lubricating materials influence the metallic surface are determined respectively on basis of sign and modulus of value ΔG: ΔG<0 indicates softening effect, ΔG>0 indicates reinforcing effect, and ΔG=0 indicates neutral effect of lubricating material under examination on the metallic surface.
EFFECT: possible estimation of influence of boundary layers of lubricating material in strength properties of metallic surfaces.
FIELD: instrument engineering.
SUBSTANCE: in invention, parameter "total impurity" is defined by change of running oil optical density with regard to fresh oil against three spectral ranges by polychromatic optical radiation transmission through oil and recording of transmitted through oil radiation intensity in three spectral ranges - red, green and blue. In addition, diagnostic parameter "chemical destruction" of oil is used to monitor oil performance. Instrument includes optical source, flow-through cell, optical radiation receiver and signal processing unit. Besides, source contains polychromatic radiation source and receiver includes photo sensor, which records optical radiation intensity simultaneously in three spectral ranges.
EFFECT: invention improves self-descriptiveness and reliability of on-line oil performance monitoring.
6 cl, 8 dwg
FIELD: physics, measurements.
SUBSTANCE: invention is related to technology for determination of temperature resistance of lubricant oils. In method for determination of lubricant oil temperature resistance, oil sample is taken, divided into equal portions, each of them is heated at atmospheric pressure without air access with condensation of vapors and condensate drain, besides for each subsequent part of oil sample, test temperature is increased by a permanent value, afterwards light flux absorption ratio Ka is determined, graphical dependences on temperature are built, and temperature resistance is detected, moreover, after testing sample is weighed, value of evaporated mass G is identified as difference of oil sample mass before and after test, evaporation ratio KG as ratio of evaporated oil sample to remained mass, coefficient of conversion energy Ec as sum of light flux absorption coefficients Ka and evaporation KG, then graphical dependences of energy conversion ratio Ec on test temperature are built, and temperature resistance of tested lubricant oil is determined by temperatures of destruction process beginning and completion.
EFFECT: improved accuracy of determination.
1 tbl, 1 dwg