The method of estimating the sedimentation stability of engine oils
(57) Abstract:The invention is intended for use in studies of lubricating oil in the oil refining and other industries in forecasting the timing of the storage of motor oils. As informative parameters use the base number and kinematic viscosity. Centrifugation is carried out for 80,5 h with separation factor 20000100 units, followed by sampling of all tubes. Samples are mixed, determine the base number and kinematic viscosity of the mixture. Sedimentation stability estimate for a consolidated index, defined as the square root of the product of the relative velocity change base number and kinematic viscosity during centrifugation. The application of the method allows you to quickly and reliably estimate the sedimentation stability of engine oils at low cost. 5 table. The present invention relates to the field of study of lubricating oils, in particular to the estimation of the sedimentation stability of engine oils, and can be used in oil refining and other industries in forecasting the reduction of the potential energy of the particles during settling under gravity /1 - Fredriksberg D. A. Course of colloid chemistry. -L.: Chemistry. -1984. S. 368 /.The objective of the study was to develop a rapid method to reliably determine the sedimentation stability.Physical and colloidal stability describes the ability of the oil to keep in the process of storing it in the real terms of the original physical condition.For the rapid assessment of physical and colloidal stability of oils with additives there are a number of methods based on visual and physico-chemical evaluation of the changes in the oil after a certain period of storage with the use of heat treatment and centrifugation of specimens tested oils.There is a method of testing time greases on the colloidal stability /2 - GOST 7934.4-74 Lubrication time. Test method for colloidal stability./
The essence of the method consists in determining the sustainability of lubrication to the delamination and separation of the precipitate. To determine the colloidal stability of the applied laboratory centrifuge CKP-3, providing a separation factor of up to 8000 units.The centrifuge defined tubes include and display for speed and time, predismissal the presence of stratification or sedimentation.The main disadvantage of this method is that it does not give a quantitative assessment of changes in the qualitative condition of the oil after the test.Also known a method of evaluating the stability of lubricating oils during storage /3-Bulgarian State standard N 14348-77. Method of assessing the stability of the oil during storage/.The essence of this method lies in the creation of heavy oil ageing by heating it to 150oC, subsequent centrifugation after reaching room temperature, cooling to the temperature of solidification and re-centrifugation after reaching room temperature. After completing these operations, the oil stored in glass containers within 60 days in a dark place at room temperature. After the test, visual assessment of oil on the presence of sediment. For tests used laboratory centrifuge, providing a separation factor of 1000 units.The disadvantages of this method is that in addition to the lack of quantitative assessment of changes in quality of the oil condition, it is also time consuming.The closest technical solution to an alleged invention and taken what's oils /4 - The decision of the state Commission for testing fuels, oils, lubricants and special fluids when Gosstandart N 23/1-79 from 17.03.80. Method qualification physical stability of the transmission and gear oils./.The essence of this method lies in keeping the sample oil at a temperature of 1005oC for 24 hours, cooled to room temperature (18-22oC) keeping the sample oil at a temperature of minus 202oC for 24 hours and subsequent storage in a dark place at room temperature for 10 days. Thereafter, the sample oil is centrifuged for 30 minutes at the separation factor 500050 units and the stability of the oil is estimated by the change in the value of indicators (critical load, the load welding, the spot diameter of the wear index bully), characterizing extreme-pressure and antiwear properties of the upper and lower layers of the oil after centrifugation.The disadvantages of this method are its duration, complexity and unacceptability for motor oils specified performance indicators to assess changes in their quality after testing.The technical result of the invention is efficiency, reducing tradspool determine the sedimentation stability of engine oils on the mismatch of informative parameters, measured before and after centrifugation of the samples, placed in n tubes according to the present invention as informative parameters use the base number and kinematic viscosity, centrifugation is carried out for 8 (0,5) hours factor separation 20000100 units, followed by sampling of all tubes, mix these samples, determine the base number and kinematic viscosity of the mixture, and sedimentation stability estimate for a consolidated index, defined as the square root of the product of the relative velocity change base number and kinematic viscosity during centrifugation.The essence of the method consists in the following. Given that the engine oils of different grades of viscosity and operational groups it is difficult to reliably estimate the sedimentation stability due to a low rate of sedimentation in motor oils under normal conditions, in laboratory tests using a centrifuge with a large separation factor, sampling oil from the centrifuge tubes with different levels and a subsequent assessment by the misalignment of the source and measured after centrifugation informative is>/P>In the proposed method of estimating the sedimentation stability of engine oils to centrifugation determine the base number (Yabout) and kinematic viscosity (o) the original sample of oil, put it in n tubes, centrifuged within 8 (0,5) hours (factor ) separation centrifuge 20000 100 units, followed by sampling of all the tubes from the upper level, mixed samples, determine the base number (Ywithand kinematic viscositycmixture and of the sedimentation stability of the oil is judged by the following dependencies:
< / BR>where Kwithis a generalized measure of the sedimentation stability of engine oils;
Kythe relative rate of change base number determined by the formula:
< / BR>Kthe relative rate of change of kinematic viscosity, defined by the formula:
< / BR>For testing has been used laboratory centrifuge, table top type T-24 /maintenance manual for the centrifuge T-24 production company "VEB MLW Zentrifugenbau Engelsdorf", 16.11.82,/, providing separation factor 20000 100 units/tubes for a centrifuge with a capacity of 10 ml.The sampling tubes (12 pieces) was made in this case with percentagedone ( ) and separation factor (f)) conducted studies on oil M-8D2To, which is composed of a significant amount of additives (10%) and has a low viscosity (80,5 mm2/s).The results are given in table.1 (see the end of the description)
The table shows that with increasing values of the separation factor over f= 20000100 units and centrifugation time more = 0,8 0,5 h the change in Kwithinsignificant and, therefore, these parameter values are optimal for motor oils.To check the options selected for tests conducted studies samples of commercial motor oils various operational groups and the viscosity. The results are given in table.2 and 3.From table. 2 shows that for all samples of oils is the most optimal mode of centrifugation of the separation factor f = 20000 100 units.From table. 3 shows that for all samples of oils is the most optimal mode centrifugation within 8,0 0,5 hThus, the optimal operation parameters are the centrifugation time =8(0,5) hours in a centrifuge, providing the separation factor f=20000100 units.The method is implemented as education is g KOH/g) and kinematic viscosity (o= 7,53 mm2/s) of the original sample. Fill n = 12 test tubes 10 ml, put them in the centrifuge rotor T-24, providing separation factor 20000100 units, centrifuged for 8 (0,5) hours ( ), and then takes samples (3 ml) of all tubes from the upper level with a syringe, mixed samples, determine the base number (Ywith=6.73 x mg KOH/g) and kinematic viscosity (c= 7,46 mm2/s) mixture.Determine the relative rate of change base number:
< / BR>Determine the relative rate of change of kinematic viscosity:
< / BR>Define a generalized index of the sedimentation stability of engine oils:
< / BR>Getting the value of the overall indexwiththis sample oil M-8D2to and comparing it with a value of Kwithreference oil of this brand, you can judge the sedimentation stability of the sample oil. The higher the value of Kwiththe more oil prone to sedimentation are included in the additives (drop them in the sediment) and the less time the oil can be stored.In this way samples were studied commodity motor oils, the test results are presented in table. 4 (see end described the La can be distinguished depending on their belonging to different operational groups (a to E) and groups of viscosity (from 8 to 20 mm2/c). The higher the value of Kwiththe oil has a lower sedimentation stability. So oil M-16G2CA (group G) is more stable compared to oil M-8D2for (group G), having a lower viscosity, and oil M-K (group D) having the same viscosity, but containing a greater amount of additives. Thickened oil (M-63/10B2M-(63/10V) are even less sediment stability in relation to nezapomenem oils, at the same time, depending on the membership of the operational group also differ in the sedimentation stability. So, with the same viscosity oil M-63/10B (group b), contain more additives than oil M-63/10B2(group B), has the value Kwithabove and, therefore, less sedimentation stability.Thus, examining a considerable number of samples of commercial motor oils, the authors state:
- oils have the same viscosity with increasing content of a number of additives belonging to the higher operational group) have a higher value of the complex indexwithand, therefore, less sedimentation steadily the number of additives), with increasing viscosity of less importance of the complex indexwithand, hence, greater sedimentation stability;
- thickened oils have a higher value of the complex indexwiththan nezahodnye and, therefore, less sedimentation stability;
- comparing the value of the complex indexwitha sample of the engine oil with the value of the complex indexwithoils of the same brand, taken as a standard, it is possible to draw the conclusion about the sedimentation stability of the sample oil and the possibility of its long-term storage.The inventive method in addition to reliability (table. 4) helps to lower labor costs in the operational definition of the sedimentation stability of engine oils (table. 5).Comparative analysis of the results of the test oil by the present method and the method prototype is presented in table. 5.From table. 5 shows that the proposed method significantly outperforms the method prototype for efficiency (29 times), complexity (fewer operations) with a significant increase in accuracy (2.5 times).Thus, the claimed method meets the requirements of patentable is th number and kinematic viscosity, characterize the sedimentation stability of engine oils);
- non-obviousness (authors when viewing patent information, scientific and technical literature is not found above essential features - the use of the generalized parameter Kwithreflecting the relationship of the base number and kinematic viscosity of the sample oil is measured before and after centrifugation);
industrial applicability (the method is simple, rapid and implement planned his introduction to the interagency methods for the prediction of shelf-life motor oils in Q1 - 1998).The use of the invention will promptly and reliably assess the sedimentation stability of engine oils at low cost method.Sources of information:
1.Fredriksberg D. A. Course of colloid chemistry. -L.:Chemistry.-1984.- S. 368.2. GOST 7934.4-74 Lubrication time. Test method for colloidal stability.3. Bulgarian State standard N 14348-77. Method of assessing the stability of the oil during storage.4. The decision of the state Commission for testing fuels, oils, lubricants and special fluids when Gosstandart N 23/1-79 from 17.03.80. Method qualification tentazioni stability of engine oils on the mismatch of informative parameters, measured before and after centrifugation of the samples, placed in n tubes, characterized in that as informative parameters use the base number and kinematic viscosity, centrifugation is carried out for 8 0.5 h with a separation factor 20000 100 units, followed by sampling of all tubes, mix these samples, determine the base number Wwithand kinematic viscositycto the mixture, and sedimentation stability estimate for a consolidated index TOaboutdetermined by the formula
< / BR>where Kythe relative rate of change base number during centrifugation, defined by the formula
< / BR>Kthe relative rate of change of kinematic viscosity during centrifugation, defined by the formula
< / BR>W0,ovalue base number and kinematic viscosity prior to centrifugation;
the time of centrifugation.
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