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                Lubricant (grease) introduced common quality indicators

                Update Time :2014-05-14The view :2832

                1) Density

                Density of petroleum and its products is the simplest and most commonly used indicators of physical properties, it refers to the quality of the material contained in the specified temperature within the unit volume, unit: kg/m3

                Because at different temperatures, densities vary, high temperatures than at low temperatures measured density measured density to be small. For comparison, the density of the oil used in general to predetermined density indicated temperature. GB regulations of the density at standard temperature (20 ℃) as the standard density g/cm3. Density is important in the production of storage and transportation, product measurement, refinery process design are used. In a way, you can judge the quality of the oil summed density but also with the number of measure conversion, delivery and acceptance of the. Simply determine the nature of oil, according to a rough estimate the density of crude oil types, such as those containing paraffin oil density is often much lower than the density of crude oil containing naphthenic and aromatics. More sulfur, oxygen, nitrogen compounds and asphaltenes and resins, the higher the density, the more oil.

                Another density can be initially identified oil varieties: Petrol P = 0.7-0.76g/cm3 aviation kerosene 0.77-0.84g / cm3 oil 0.87-0.89g/cm3

                Density can be approximated by assessing the quality of oil and chemical composition changes, especially in the storage and transportation process, found a significant increase or decrease in the density of oil, you can determine whether mixed with heavy oil or light oil.

                2) Viscosity

                Lubricating viscosity is an important physical and chemical indicators, classification and grading of various lubricants, quality identification, identified uses of decisive importance, but also the design calculations indispensable physical constants. Liquid, semi-liquid state of matter in by external force, and the friction between the flowing molecules presented or the resistance.

                We and international standards, with a kinematic viscosity m2 / s, the actual production of common mm2 / s relationship between the two is 1m2 / S = 106mm2 / S (crude oil)

                The degree of viscosity of the lubricating oil changes with temperature, the viscosity-temperature, generally elevated temperatures, the viscosity decreases, the temperature decreases, the viscosity increases, the viscosity ratio refers to the oil at a predetermined temperature measured by the two compared kinematic viscosity at low temperature ratios of kinematic viscosity and higher temperatures. country and the international ISO standards, using 40 ℃ and 100 ℃, the viscosity index is the oil viscosity changes with temperature characteristics of a convention this magnitude, high viscosity index, which means that oil change with temperature is small, the table can be found by so viscosity oil production and use for what is the point?

                (1) increasing the viscosity of the engine, it will affect the power, the viscosity is too low will cause starting difficulties and reduce their ability to support the film.

                (2) Most lubricants are divided according to the viscosity of the lubricating oil is the choice of a basis.

                (3) viscosity differential cooling effect. Due to a slow cycle times less through the filter, washing effect is poor.

                (4) low viscosity oils, the film easily broken.

                (5) good sealing effect.

                (6) increased oil consumption.

                3) Oily

                Lubricant oil is the adsorption of the metal surface to reduce friction performance, improve oil performance, minimal wear protection with a minimum coefficient of friction. Such additives are generally polar molecules can be adsorbed on the orientation of the metal surface to form a solid film that can withstand high strength. But you can not play the role of extreme pressure. Average high temperature extreme pressure lubrication will reduce polar molecule adsorption. Oiliness agents used with other additives such as antioxidant, anti-rust compound for spindle oil, hydraulic oil, rail oil, oiliness agent was added so that the general low-load, to ensure adequate and effective agent for oil resistance, high temperature, high load almost oily agent without any effect, while the anti-wear extreme pressure agent at low temperatures, but the wear is increased at low load.

                4) Acid

                And the number of milligrams of potassium hydroxide required for Ig petroleum products, said acid number of acidic materials in mgkoH / g, said (generally refers to the measured value is not additive). Determination of acid in the oil acidity is measured organic acids, inorganic acids and other acidic substances gross, but mainly organic substances.

                Determination of the role of acid value:

                (1) The higher the acid number, indicating that the more acidic the oil contained in the material, the more highly corrosive force.

                Corrosive (2) to determine the oil-to-metal

                Organic content of less oil, no water when things do not have a corrosive effect on metal. When the presence of water, low molecular weight organic acids can also be immediate trace metal effect device, the equipment corrosion, an organic acid is aluminum or zinc metal corrosion, metal soaps generated, causing the oil to accelerate the oxidative deterioration, while aggregation oil soaps the formation of deposits.

                (3) determine the degree of deterioration of the oil

                Lubricants used for a period of time, due to the role of oil heat and oxygen oxidative deterioration, increased acidic substances, corrosion of equipment.

                (4) After some oil additives, the additive itself is an acid, the acid value is increased, such as: rust turbine oil additive prior to an acid value less than 0.03mgkoH / g, the acid value of additives in 0.3mgkoH / g or less. And therefore can not always judge the quality of the oil from the acid value size.

                (5) the operation of the oil, acid value measured mainly to see how deep oxidation, thus long life expectancy. Of course, other performance tests, such as rust to be accurate.

                5) pour point, freezing point

                Under standard conditions of the oil, the minimum temperature to continue the flow of cooling known as pour point.

                Oil under standard conditions, to a maximum temperature of cooling liquid does not move as the pour point.

                Currently the world are represented with a pour point temperature performance.

                Pour point and low pour point oil is an important indicator of liquidity. Mechanical choose to use a lubricant at low temperatures generally used lubricants 10-20 ℃ lower than the pour point temperature in the high temperature zone is not necessary to use a low pour point oil, because the higher the lower the pour point of the oil off the wax deeper cost . Effect of the low-temperature fluidity lubricants, and viscosity, containing little or no wax wax oil, lubricating oil is reduced to a certain temperature, the viscosity increased significantly, but also make the lubricating oil lose flowability. Therefore, when low oil sampling, in addition to considering the pour point should be considered low viscosity. This viscosity-temperature solidification. Another is the solidification structure, including the time when the oil temperature is gradually lowered wax, wax oil contained in the melting point is reached gradually crystallized, and then continue to cool, crystalline wax to form a network, so that the whole oil loss of mobility, which is constructed solidified. Then measured pour point, pour point is the point?

                (1) Since the pour point of different petroleum products, loss of flowability when used, different temperatures to determine the low temperature fluidity

                (2) pour point oil containing wax, it can be used as indicators of the estimated paraffin content, because the more paraffin oil content, the more easily solidified

                6) rust

                Is the lubricant plus a certain number of additives, the oil has to prevent metal corrosion performance. General turbine oil under working conditions, often in water, the presence of steam. Not only will a lot of water vapor oil emulsion, and severe corrosion of equipment can. Lubricant adhesion of metal itself in the presence of water vapor, it is easy to be destroyed, to add a certain amount of strong organic compounds, so tightly adsorbed on the metal surface, the water out of contact with the metal, you can play rust effect. Rust assessment methods in general use liquid rust test. According to Japan's machinery industry accounted for investigations amount of corrosion loss of 2% of GNP, while the cost compared to direct losses for rust 0.06%. Visible rust significant. Use more general rust rust oil (fat) long, are made of a permanent anti-corrosion coatings, electroplating, plating rinse, rust mostly petroleum oil lubricants base oil, adding rust rust oil made in this at room temperature and heating conditions, using immersion, spray and other laws applied. Coating on the metal surface from the protective role in the preservation period of time, to be used to wash, but also in the oil system, (such as an internal combustion engine, turbine and hydraulic systems), the use and operation of the common storage for lubricants oil, which play a role in anti-rust sealed. When unsealed start, not another one in the oil, direct operational. There is also sealed in the packaging material and containing volatile gases chronic rust, rust generally refined oil having a viscosity of more than 40 ℃ at 15-20mm2 / s or less, mostly.

                7) Water

                Water present in the oil state, there are three

                (1) was suspended in water

                To form fine droplets of water suspended in oil, making the emulsion, such a situation can be removed by drying in vacuo.

                (2) was dissolved in water

                Water uniformly dispersed in the molecular state of the hydrocarbon molecules, called dissolved water. The amount of dissolution depends on the chemical composition and temperature of the oil, the higher the temperature, the more the amount of fusion. Because much melting capacity, can not count.

                (3) free water

                Precipitation of fine water particles, gathered in large droplets, was settling down from the oil water separator state exists

                Usually anhydrous oil analysis (0.03% or less traces) that are not suspended in water and the free water, it is difficult to remove the dissolved water. Then the oil in the water, what harm it?

                A, oil in the water freezes in winter, clogged pipes and filters

                B, the presence of water resistance and increase oil emulsification

                C, reduce the oil dielectric, causing severe short-burning device

                D, oil and water, easy to produce bubbles, reduce film strength

                E, water accelerate oil oxidation

                F, water with low impurities and oils precipitate formed, called sludge

                G, lubricating water temperature to produce steam, destroy film

                H, of ester oils, additives also hydrolysis, precipitation, even if such removal of the water, can not restore the original performance additive

                M, experiments show that adding a dripping oil shortening bearing fatigue life of 48%. When the water exceeds 0.10 /, producing cavitation line may test more than 0.5% causes serious wear, shorten the life of more than 3% to 85%, generally below 0.10% control.

                Water in lubricating bearings generally means death. Oil containing 0.2% of water, bearing life will decrease by half. 3% of the water is only 15%, once emulsified oil, the oil must be renewed. Therefore, you must tighten the oil filler, oil drums put dry location. Such as open storage, horizontal stacking should reduce barrel mouth water, avoiding barrels "breathe" sucked moisture.

                American inventor confirmed magnetic seal, seal such devices can be completely isolated from the cavity and the outside atmosphere. But problems can not leak any moisture chamber, in whole condensate. Any kind of oil will inevitably emulsion, until now a very strong anti-purple oil emulsion, the problem was solved.

                DANA the known U.S. WARREN pump, the purple oil was added 30% water, 50% oil-bearing capacity when a new still purple, and its water resistance greatly increased over safety equipment operation.

                8) mechanical impurities

                Mechanical impurities in oil is suspended precipitate insoluble material in the lubricating oil. Most of sand, clay, iron, rust, caused harm to:

                (A) destruction of the oil film, increased wear

                (2) clogging pipes and filters, lubrication caused by failure

                (3) grease the machine noise ratio against big oil, remove difficulties

                (4) organic hybrid transformer oil will reduce the insulation performance

                Requires less than 0.10%.

                9) Demulsibility

                Demulsibility also known as emulsion breaking time. Under specified conditions so that oil mixed with water to form an emulsion, and then at a certain temperature stationary. Complete separation of oil and water, the time required in minutes (min), said the shorter the time, the better the resistance to emulsification, emulsion breaking performance measurement method. The test temperature was 54 ℃ +1 ℃ oil viscosity 40 ℃ 28.8_90mm2 / S to take samples and distilled water each 40ml, at the rated temperature 1500r/min, stirring 5min, start recording emulsion and water separation time, such as 1h after standing, it can not be separated, then hold divisions, oil, water and emulsion ho liters

                Reporting methods

                (1) Within one hour stirring, the emulsion layer is equal to or reduce 3mL, the record at this time is the number of layers ml, and report the results. Well as completely separate 20min should be recorded as (40-40-0) 20min

                (2) If not completely separated 20min emulsion layer has been reduced to 3ml, should be recorded as (40-37-3) 20min.

                (3) After one hour, the emulsion layer 3mL still more, such 5mL, this time for the oil 39ml, water 36ml. Emulsion layer is 5ml should be recorded as (39-36-5) 60min emulsified oil annoying thing is bad, destroy the film emulsion, foam, led to deterioration, reduce lubricant performance, but will generate a soluble sludge clogging lubrication system, mixed with impurities such as oil, is easy to emulsify, and not breaking, increased oil emulsion viscosity, high resistance, accidents will happen, but emulsified against hydraulic oil, cutting oil and rolling oil extremely needed, they are also needed good emulsion stability. Anti-oil emulsion is an important performance industrial oils, industrial gear oil requirements such as extreme pressure anti-wear, oxidation, rust, but also good resistance to emulsification, gear oil with water because multiple opportunities to Demulsibility worse case water emulsion, lower lubricity and flowability, causing wear. Turbine oil, frequent contact with water, the condensate water into the oil, turbine oil requires a good ability to trap the same token, an important indicator of the anti-emulsification antiwear hydraulic oil, hydraulic oil, especially zinc poor demulsibility. Turbine oil is inevitable in contact with water vapor to form a temporary emulsion, such as anti-emulsification poor water inseparable, will lose lubrication, accelerated engine wear.

                10) anti-foam

                Vapor bubble is a phenomenon that appears dispersed oil, bubble sizes. Large rapid burst duration longer small. According to Stoke's law, the separation bubble, bubble speed is proportional to the square of the diameter, and inversely proportional to the viscosity of the lubricating oil. Also the rate of destruction of the surface tension of the oil on the foam, and the surface tension of oil processing depth. When the surface tension of oil to maintain long-lasting, because the foam produced the following categories, with the air refueling into lubricating oil while stirring spray, splash, and also exposed to the air, oil from the high pressure zone into a low pressure area, the air be released, in addition, extreme pressure agents, corrosion inhibitors, detergents greatly increase the oil foaming, the foam oil, oil will cause loss of efficiency and lack of intermittent supply of the oil to accelerate the oxidation of the oil lubrication system of air resistance, hydraulic system can be compressed foam performance elasticity, crawling, affecting the accuracy of the automatic control of hydraulic systems, such as aviation jet engine oil system capacity is small, such as anti-foaming poor, oil may overflow from the vent. Liquid level indicator or false, can not be found in oil, anti-foam agent's role is to reduce tension and bubble foam stability adsorbed film, shorten the time bubble exists. But it can not prevent foaming. Anti-foam agents used dimethicone, because of its viscosity, (25 ℃ at 100-1000mm2 / S) and a small amount, and diluted with hot kerosene (kerosene and simethicone = 100 to 1) use, carried out with vigorous stirring into the oil, silicone oil is uniformly dispersed in the oil, the silicone oil added in an amount of 50-10PPM, quite 0.001% -0.0005%. Silicone oil for oil anti-foam Although good results, but at the same time releasing the air deteriorates, also found its defoaming persistent poor, affecting anti-foaming ability. So now people are using non-silicon polyester foam agent (T912).

                Determination of anti-foam is the pass into the air when oil or stir anti-foaming foam volume size and the speed. Method is: 200ml 1000ml oil sample into the cylinder, according to (1) before 24 ℃, (2) 93 ℃, (3) after 24 ℃ measured three programs generated. Specimen with a certain velocity (94Mi/mIh) After air was blown under 5min, produce large amounts of foam, the foam volume immediately above the oil level mark (ml) of said foaming tendencies, the aeration is stopped, still 10min, the recording volume of the residual foam , said foam stability for 93 ℃ complete, remove the cooling cylinder 43 ℃, 24 ℃ and then placed in a thermostat, the foam volume was measured at the same temperature, the entire process is completed within the 3h.

                11) air release

                Air release means to release the air from the oil out of the performance test, the method of measuring the air is released into the sample was heated 25 ℃, 50 ℃ or 75 ℃, blown by excess sample fluid pressure air (aeration 7min ), the sample was stirred vigorously, the formation of small air bubbles (air mist) in the sample, the gas stop, recording the sample volume of air is reduced to a mist of 0.2% time (min) is the time of the bubble separation time . Process air release, separation time shorter, which means that the air is released, the better. Bubble test is to measure the volume of oil foaming and foam stability, and air release oil is measured in (diameter <0.5mm) precipitation air speed, usually the larger the oil viscosity, air release and anti-foam more poor. General wear hydraulic oil HM32.50 ℃, air release value not greater than 6min, No. 46 is not greater than 10min, turbine oil No. 32 is not more than 50 ℃ 5min, No. 46 is not greater than 6min.

                12) Flash Point

                Heating oil under specified conditions, when the gas oil vapor mixed with air in contact with fire, a flash fire occurred minimum temperature phenomenon called flash point. The so-called "flash fire" is limited to the burning moment, flashed immediately extinguished. If reheating steam evaporation resorted enough to sustain combustion played 5s, the minimum temperature at this time, said ignition. Lubrication ignition flash point higher than about 20 ℃ -30 ℃.

                There are two kinds of methods measuring the flash point, open cup and closed cup. Usually evaporate large light petroleum products, the use of closed cup, heavy oil is used for open cup method. Flash Point is usually lower than the opening flash point 20 ℃ -30 ℃.

                Determination of flash point of oil to use what is the point?

                (1) Flash Point often used as safety indicators oilseeds. Flash Point low, indicating that the oil lightweight components more volatile fire, should be saved. Note the use of the general temperature is lower than the flash point of 20 ℃ -30 ℃. Flash Point large low oil evaporation loss, increased viscosity, affecting the normal lubrication.

                (2) low flash point, indicating the number of the light oil fraction containing used to determine the appropriate temperature.

                (3) flash point of a drop of the oil may be mixed with light oil content.

                (4) The flashpoint is safe to use, an important indicator of transport, the use of storage temperature is generally below the flash point 20 ℃ -30 ℃.

                (5) turbine oil, transformer oil flash point drop (typically decline 5-8 ℃). Showed severe oxidative deterioration of oil should be replaced with new oil.

                (6) Oil fire danger rating is based on the flash point to the division. Flash point below 45 ℃ is flammable. Average gasoline products (including solvent oil) flash point are below 0 ℃. Is absolutely inflammable and explosive materials. Like airplanes, cars with gasoline, jet fuel, refueling point 20m away from extinction. Pipeline to be grounded to prevent static sparks detonated, the operator must not wear nail shoes, wear anti-static clothing, and not to beat with a hammer piping, use wrench should be aluminum and copper to avoid sparks. Because the world oil system fires caused by static electricity and 80% per annum explosion.

                13) carbon residue

                Carbon residue is the oil under specified conditions (barrier into the air) heat evaporation, pyrolysis and combustion charred like residue formed to account for oil residue weight expressed as a percentage, generally there are two kinds of measuring methods, one Kang style law, and second electric furnace, electric furnace method used. The method is to first increase compliance porcelain crucible placed in 800 ℃ ± 20 ℃ high temperature furnace cooling after calcination 1h accurate weighing, measuring power to make carbon residue furnace temperature constant in the range of 520 ℃ ± 5 ℃. The above is called the excess into the sample crucible covered with lid, when the sample is heated to steam escaping from the lid in the oven capillary immediately ignited combustion remained at the end of 520 ℃ ± 5 ℃. The residue was calcined samples were heated to the residue from the end of the calcination totaling 30min, then the crucible was taken out from the furnace and cooled after 40min weighing, namely electric furnace carbon residue.

                Evaluation of carbon residue is tendency indicator of oil coke generated under high temperature conditions. Then measure the significance of residual carbon?

                (1) according to the size of carbon residue value can largely determine the oil in the coking tendency. In conjunction with other indicators can determine the depth of oil refining, generally deep oil refining carbon residue small, multi-lubricating carbon residue increases mechanical equipment friction, wear. The main substance formed carbon residue oil is oil resin and asphaltene and polycyclic aromatic hydrocarbons.

                (2) carbon residue is one of the main engine oils and compressor oil quality indicators. When these machines work, some oil evaporation, combustion, decomposition, oxidation, forming a film and not fuel, along with other impurities in the formation of coke deposition, affecting heat dissipation, so that the ignition spark plug is not working. Deposited on the valve will not only burn and cause explosions. Pull the cylinder caused by excessive carbon residue even hold tank.

                14) corrosion

                Corrosion test was measured at a temperature of the lubricating oil caused by the change in color of metal corrosion, the specific method is to clean the solvent after finishing the sheet metal (copper), steel or other metal sheet, usually with copper, in the suspension a glass rod was immersed in the oil, after the predetermined temperature (100 ℃) Hold time (3h), washed with a solvent taken out to observe the color change of the metal sheet, whereby to determine the signs of corrosion.

                Corrosion standard direction





                Mild discoloration

                1a pale orange, almost the same as the new polished copper

                1b deep orange


                Moderate discoloration

                2a purple

                2b lavender

                2c lavender blue or both, and were covered with purple multi-colored

                2d silver

                2e brass or golden yellow


                Color depth

                3a magenta covering the brass-colored multi-colored

                3b red and green multi-colored (malachite green), but not with gray



                4a transparent black, dark gray or brown with only malachite green

                4b graphite black or matte black

                4c shiny black or dark shiny black

                According to a qualitative change in the color of the oil to check whether the corrosion test, such as the active metal sulfides or free sulfur, hydrogen sulfide and elemental copper corrosion is very sensitive to the presence of sulfur. These small amounts of low molecular weight organic acids and water-soluble active sulfides are caused by bad because the oil refining, the corrosion test what is the point?

                (1) oil in low scores in organic and inorganic acids on copper, aluminum, tin and other metals and their alloys have strong corrosion resistance, increased wear and sludge in the device will pay for damage to the movement.

                (2) sulfide corrosion will accelerate the deterioration of engine oil, produce large amounts of sludge and coke.

                (3) Activity of sulfur in the oil, the free acid compound of sulfur and copper, aluminum, metals are strongly corrosive, but the neutral polar molecules sulfide can improve performance of oil, was added to form a strong reaction film.

                (4) oil use, the acid value to a certain extent, it will cause corrosion of parts, so the extent of the corrosion test also identified oil deterioration, if the failure should be replaced immediately.

                American Standard ASTM-130 copper corrosion (2700F)

                Determination of resistance to three hours that grid, purple oil is resistant to 200 hours, more than 60 times. Great protection for harsh environments force.

                Superior penetration purple oil, anti-rust corrosion inside the rope to make a good gauge protection. By ultrasound probe found that purple oil on the cable break protection, special ropes several times in the major oil companies oil. Containers to prevent falling.

                15) Oxidation stability

                Lubricant during use at elevated temperature, oxygen, metal catalyst and other factors, will gradually oxidative deterioration. We oxidative deterioration of lubricating ability to resist heat and metal in the catalytic oxidation stability of lubricants called. But also the ability of anti-aging oil is lubricating durability indicators also use storage and transportation process oxidative deterioration of important features.

                Oil oxidation

                (1) produce acidic materials. Acid value increases, the metal has a corrosive effect, reduce the insulation performance of the oil. After the oxidation of gum, asphalt corrosion of equipment

                (2) an increase in viscosity. Machinery and equipment necessary to consume some of the power, after an increase in viscosity, oil heat, poor cooling effect deteriorates.

                (3) precipitation: the sludge. Crud from brown to black, wherein the composition is generally 50-70% oil, 5-30% water, 5-20% of asphalt, and some glial mechanical impurities, they will obstruct the line, hole filters.

                All lubricants which are according to their chemical composition and different conditions, and auto-oxidation of different tendencies. Due to the different oxidation stability, oil change period is different. Turbine oil oxidation stability as well, and some can be used continuously for more than 10 years. The difference is less than 2-3 years, or even less. Oil at room temperature, oxidation is slow, the above 50 ℃. If catalytic oxidation significantly. Generally can be divided into three phases, the following 125 ℃ slowly oxidized to produce acid precipitation. 125-200 ℃, oil vigorous oxidation, film formation, and coke. When more intense than 200 ℃, part of the combustion, coke, can not be used. Another oil oxidation is also affected by the pressure, the oxygen content of air per unit volume increase (oxygen partial pressure) greater oxidation, pure oxygen under special circumstances, that is not high pressure will react violently, causing an explosion. Therefore, the oxygen compressor or oxygen bottles are prohibited lubricants, and glycerin or soapy water, then what is the meaning of oxidation stability in the use of it?

                Generate acid corrosion of equipment (1) oxide, should be given special attention.

                (2) minimize contact with oil and air, such as reducing the storage tank space.

                (3) try to avoid direct contact with oil and strong catalytic properties of copper and aluminum, shorten the oil in a metal container storage time.

                (4) minimize oil use and storage temperatures.

                (5) oxidative deterioration of oil remaining in the tank, the oil change must be cleaned. As long as there is a small amount (5% -10%) of oil mixed with new oil, new oil will significantly reduce the oxidation stability.

                (6) Since the service life of oil oxidation stability can be determined, then the precision machine tools, hydraulic system oil, and fuel consumption great equipment, good oxidation stability should be selected or added antioxidant additives in lubricating oils.

                (7) compressor oil, oil is often in contact with the hot oil, highly oxidative decomposition, the decomposition of certain oil and gas mixed with oxygen concentration and temperature, spontaneous combustion may cause an explosion, so the oxidation stability is a very important indicator.

                The methods generally measured at a certain temperature, oxygen was then added to the catalytic metal, so that a certain time of oil oxidation, the measured viscosity, acid and the precipitate was used to determine the antioxidant properties. There are usually several ways.

                A mineral oil oxidation characteristics plus inhibitor assay (GB/12581-90)

                In the sample at 95 ℃ and water, especially, the presence of a copper catalyst, the reaction with oxygen, the oxygen gas per hour through 3L, the oxygen was continuously, the oil acid number 2mgkoH / g, the time required in hours, the longer the time, the better the oxidation of oil. For example: TSA turbine oil No. 32, No. 46 hydraulic oil and gas to reach 3000h 1000h, acid value not greater than 2.

                B extreme pressure lubricant oxidation characteristics assay, (SH/0123).

                The test oil pass into the air, 10 liters per hour at 95 ℃ vessel oxidation 31h, the percentage increase in oil viscosity measurements, measuring sedimentation by centrifugation. Industrial enclosed gear oil ckc by oxidation after 95 ℃, the viscosity increase of not more than 10% ℃ kD by oxidation after 212 ℃, the viscosity increase is not more than 6%, the precipitation is not greater than 0.1ml. The quality demanded of U.S. Steel 224 gear oil standards.

                C aging characteristics.

                Compressor oil at a high temperature oxidation of work must have good performance. Referring to the foreign country also has standard SH/T0192, test conditions at 200 ℃, pass into the air 15L / h, adding air 15L / h, adding Fe2O3 oxide 24h, evaporation loss rate measurement of oil and Conradson carbon residue percentage increase (i.e. POT value). DAA compressor oil without Fe3O3, oxidation is not more than 15% of evaporation loss. POT value is not greater than 1.5% -2%, DAB oxidation compressor oil plus Fe2O3 0.3% -1% POT.

                D rotating bomb method SH/T0193 said RBOT law

                With 10% water and is equipped with oxygen bomb test oil added to the copper coil, and at room temperature, oxygen bomb End oxygen to 6kgf/cm2 constant temperature oil bath at 150 ℃, the oxygen pressure rose 14kgf/cm2 oxygen bomb bomb with water 30 ℃ way inclined 1r/min, trial Petroleum oxygen is oxidized, oxygen pressure decreased, when dropped from the highest point to 1.7kgf/cm2, the time required to min meter, strong antioxidant properties, oil time than long and generally have more antioxidants oil time 200min.

                16) Penetration (penetration)

                Penetration grease grease consistency is to identify common indicators and basic performance requirements. Penetration is the foundation of values divided grease grades.

                Determination of cone penetration is to the quality standards specified grease cone penetration depth in the 5S bell, called grease penetration. In 0.1mm increments, such as the penetration depth of 300 piercing 30mm, brief process is: to reconcile even the grease sample, carefully loaded into the work, the temperature within the specified (25 ℃ ± 0.5 ℃) within the range of thermostatic after a rate of 60 times per minute, working up and down 60 times in a row, after removing the lid, fill the hole working conditions in the absence of the cup, after planar, release pine cone, making freefall 5s ± 0.1s , then taper rod clamp, the instructions read from the disk under 1/10mm value. Penetration bigger, softer grease, the smaller cone penetration, the harder grease.

                Determination of cone penetration so the impact on the performance of the grease?

                (A) the extent of thick

                When the mechanical surface load is large, small application penetration grease, or because they can not bear the load being squeezed out. If friction is small, application penetration greater fat. Otherwise difficult to form a film. Usually on the 2nd, the 3rd, because the degree of hardness is more suitable, more widely used.

                (2) Strength

                Penetration to some extent can be expressed grease plastic strength, which can squeeze a preliminary understanding of the anti-grease and anti-shear capacity.

                (3) liquidity

                Penetration value reflects the degree of difficulty to produce grease flow under loads. Penetration bigger, softer, more easily flow. Penetration is usually 220_340, if penetration of more than 400, loses plasticity, becomes semi-fluid. At this point it loses the characteristics of grease to maintain a fixed shape, need to add new grease. We often put pressure feed cone penetration lipid control in less than 290 (ie, 2). Consistency of the grease into nine grades:

                     Fused into grade Penetration

                     000 445_475

                     00 400_430

                     0 355_386

                     1 310_340

                     2 265_295

                     3 200_250

                     4 175_205

                     5 130_160

                     6 85_115

                (4) grease mechanical stability

                Mechanical stability, also known as shear stability. Depending on the strength of its fibers thickener. Bearing in speed \ large working under intense vibration, good mechanical stability must be selected grease. Reaction to some extent due to mechanical stability of grease longevity. Continuous mechanical stability is poor after penetration cut to measure, one way is to put grease into the grease pound electric devices, and 60 times per minute, 5,000 times, 10,000 times, thousands of times a month. Measured before and after its cut cone penetration value changes. In practice, the determination of cone penetration There are two ways

                1) Full-size cone penetration

                Its measurement range of up to 620 for a standard cone. Full-size cone penetration and can be used several ways

                a) Work Penetration, refers to the work of cone penetration is penetration, work is work samples were 60 times back and forth to work after the determination.

                b) Work Penetration, stir it into the sample within less work, direct measurement without work.

                c) to extend the work of cone penetration, the number refers to the work of more than 60 times. If 10,000 times measured after 100,000 times, also known as shear stability.

                d) Block Penetration, cut into pieces, the work is not directly measured in the cone.

                e) After the petroleum grease cone penetration, melt samples were cooled in diameter 100mm depth 65mm, inner cylindrical containers to direct determination of the cone.

                2) the actual work, as well as 1/2 cone penetration and 1/4 cone penetration. Mainly used fewer samples. It applies only to the full-size cone penetration value 175_385 range. The disadvantage is that a large error of measurement results. 1/4 cone penetration called micro-penetration.

                     Full-size cone penetration = 1/4 cone penetration X3.75 +24

                     Full-size cone penetration = 1/2 cone penetration X2 +5

                No. 000 is very soft applicable centralized lubrication

                           If the fluid

                00 If applicable centralized lubrication fluid

                No. 0 as fluid suitable for centralized lubrication or smear

                1 cup soft butter apply grease gun or centralized lubrication

                2 cup soft butter applicable \ grease gun

                3 cups fat thick applicable \ grease gun

                4 cup fat stiff applicable \ grease gun

                The 5th block as hard as soap grease cup filled applicable

                6 blocks as hard as soap grease cup filled applicable

                17) Dropping Point

                Grease dropping point is heated under specified conditions, from the instrument temperature drop of liquid dripping grease cup (or out of column length 25mm) when. Dropping point is a measure of the degree of grease resistant.

                Dropping point is measured by the method GB/T4929_85,

                When measured according to the provisions of the fat-like into the cup and mix together butter cup and thermometer tube, then put the tube into the oil bath, heated by the prescribed speed, fat-like heat to soften, gradually revealing the hole from the cup, when it drops out when the temperature first drops of fluid, is the kind of fat drop point.

                Measuring the dropping point what is it?

                (1) an overview of grease type, composition, temperature limit. In general the higher the dropping point, the better the heat resistance. General temperature drops below the point 30-50 ℃. Lipid droplets in the range of several common points

                    Calcium-based grease 70-100 ℃

                    Calcium-based grease above 170 ℃

                    Compound calcium above 180 ℃

                From the drop point can roughly determine the type of fat.

                In a short time a few seconds, dropping point temperature use as boundaries. It should be noted that the dropping point is not the only determining parameter the maximum temperature grease, see also under high temperature consistency, the base oil of antioxidant capacity thickener, colloidal stability under high temperature and other parameters.

                (2) melting point, can only approximate. But not as accurate melting point.

                (3) the oil, in the determination of the thermal oxidation stability is not good drop point, and tend to drip oil separation soap, then it does not mean the melting point, which represents the temperature of the oil significantly.

                (4) the softening of some fat, only softened without melting, soft to a certain extent (approximately 400 rather than cone penetration) measured to an oil column and fall naturally elongated strip and not drop.

                18) evaporative

                Grease evaporation, and is required under the temperature and other test conditions. In the evaporation within a certain time to represent 0/0 (weight). Evaporation Evaporation grease base oil mainly caused a corresponding increase in the concentration of fat in the soap, generally 200-300 ℃ grease begins to evaporate, the evaporation 350-450 ℃ significantly, leading to changes in the consistency of fat, increased friction large. Hardened grease dropping point change, acid increases oxidative oil shorten life. If fat loss of 50% in the base oil, it will cause a lubrication failure. Therefore, the evaporation of heat, grease life wide temperature range, a large impact.

                Evaporation of fat, you can not inject into the sealed bearings. Motor bearings and difficult to replenish fat, and maintenance cycle of bearings. Nippon Steel Corporation, the provisions of perfusion lubricating grease, according J1SK2565B method, by 98.5 ℃, hot air 22h, fat should not exceed 20% of the amount of evaporation. Provisions of GB7322-94 extreme pressure lithium evaporation less than 2%. SH/T34-90 extreme pressure lithium complex, evaporation is less than 1%.

                Determination of evaporation methods are:

                SH/T0337. The sample is filled with grease 1mm steel dish (diameter 21mm) placed in special constant reactor. At a predetermined temperature, to maintain a certain time, measured the percentage loss of quality.

                When using vacuum grease, often due to evaporation caused special problems, such as rockets, satellites and other space carrying body are exposed to very low pressures. Under such conditions, even under relatively low temperature, the evaporation rate will be greatly accelerated. So that the oil is reduced. Oil vapor formation of certain optical instruments mirror film can not be used to control sensors on satellites, once attached to the oil, it absorbs infrared light, loss of sensor function.

                19) colloidal stability

                Grease a small amount of condensate oil in the long term or long-term storage. This phenomenon is called the oil. Ability to resist grease oil called colloidal stability.

                Grease is a colloidal system. Thickener fibers between capillary action relies adsorbed amount of base oil. When the colloidal system by gravity and external forces, temperature rises, will make changes in the structure and precipitation of colloidal oil. When the colloidal system is destroyed, while precipitation will occur more oil fiber structure disintegrated. Thus losing the ability to grease. An ideal grease lubricated motor bearings, the oil should be appropriate, because this strong bearing lubrication. If oil rate of 0.20% / h or 2-10% / 500h as well.

                Loss of grease as oil reaches about 50% of the original oil content, will lose lubrication.

                Grease colloidal stability, with oil% of said determination of the amount of oil used grease steel mesh oil assay (SH/T0324-92) Specifically: cone made of stainless steel wire mesh, mesh 60 , will

                10g butter into the cone network, the cone nets hanging in the beaker, this beaker 100 ℃ oven, and 30h after the determination of the oil flow from the cone net weight, expressed as a percentage, the average car Universal Lithium 100 ℃ , 3h

                Steel oil does not exceed 5%, GM lithium 100 ℃, 24h oil, not more than 10% of 1 #, 2 #, 3 # does not exceed 5%.

                There is also a pressure oil assay (GB/T392-77)


                Pressure oil is a piston, the piston is coated in grease as a pie-shaped 40mm, thickness 2mm, filter paper underneath to absorb the pressure of the oil. Upper pressure piston cone 1kg weight, at room temperature 15-25 ℃ feed

                OK. After pressing 30min, then measuring of the oil, the general synthetic aluminum complex grease of the oil pressure is not more than 10% on the 1st, the 2nd is not more than 8%, no more than 6% on the 3rd, the 4th of not more than 4 percent.

                Yet another is to funnel oil assay. (SH/T0321-91)

                The sample is mounted in a quantity of grease placed in a filter funnel. Count mass at a temperature after a predetermined time, the percentage of separation. If 2 # aviation grease 75 ℃, 24h not more than 30-6%.

                20) mechanical stability (shear stability)

                After the performance of the grease by mechanical shearing, resulting in changes in consistency, said mechanical stability. Grease in the mechanical work by shearing some parts of the high shear rate, because some parts of additional grease is limited, the only other such maintenance can greasing bearings mechanical stability requirements are more stringent.

                Two methods are currently assessing the mechanical stability.

                (1) 10

                Penetration million times sheared changes. The fat-like load of work, a continuous operation in the automatic cutting machine 20.7h, cone penetration test, cone penetration difference before and after shearing, ie mechanical stability immediately after the end of the run. Usually after the shear

                Soft, cone penetration increased. The smaller the difference, the better the stability we require. Pouring grease lubrication should not exceed the difference between the 30, the difference between small, mechanical stability are good. Shell A lithium grease 100,000 times cut difference in the Cone Penetration

                25, China's lithium grease 100,000 times after shearing, poor penetration of more than 50.

                (2) Stability roller cone penetration test (SY2725-765) installed in the drum-like 50g fat, 50 ℃ to 165r/min speeds 4h, and then measuring fat-like, slightly cone penetration, rolling around the cone penetration of micro-it means the difference between fat stability. Drum test method to work more closely simulate the grease in the bearing condition.

                Mechanical stability is usually 105 times and 60 times the difference between the work of penetration to represent. The smaller the difference, the better the mechanical stability. In general, the difference is more than 30 times as excellent, 30-60 as good difference, the difference between 60-100 fair.

                21) grease oxidation stability

                Grease storage and use, the ability to resist oxidation of said oxidation stability. Grease a result of oxidation.

                (10 free organic content of free alkali content reduces or increases.

                (2) decrease in dropping point.

                (3) the appearance of darker, appear different odor.

                (4) consistency, ultimate strength, similar to the viscosity drop.

                (5) to form corrosive products to metal corrosion, increased bearing wear.

                (6) generating depleting substances grease structure, resulting soap oil separation.

                As a result of oxidation is directly related to grease the maximum temperature and length of life is an important indicator.

                In order to improve grease oxidation stability, in addition to using a good anti-oxidant properties of the base oil, in general, in addition to the grease antioxidant additives.

                Oxidation stability by SH/T325 bomb method

                After weighing on the fat-like broken glass inside, and then placed in stainless steel oxygen bomb at 99 ℃, 100h, 0.77MP, like oxygen bomb fat oxidation.

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