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Shenzhen Evert Lubricating Oil Co.
Service Hotline：400-993-1236
URL：http://www.szaifute.com
Address: Xixiang Gonghe Industrial Road, Xixiang street, Baoan District, Shenzhen.
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Indicators for industrial lubricants |
| release time：2019-06-29 viewed：3636次 |
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Density and relative density
Relative density refers to the ratio of the normal gas density of a substance at a given temperature to the density of a standard substance at a standard temperature. The standard substance for petroleum liquids is water.
Viscosity
The measure of internal friction force during liquid flow is called viscosity, and the viscosity value decreases with the increase of temperature. Most lubricants are branded according to viscosity. There are generally five ways to express viscosity, namely, dynamic viscosity, kinematic viscosity, Enshi viscosity, Rays viscosity, and Sykes viscosity.
Dynamic viscosity: a measure of the internal friction force of a liquid flowing under a certain shear stress, the value of which is the ratio of the shear stress to the shear rate of the liquid flowing. In the legal unit of measurement in China, Pa / S is used as the unit. It is customary to use Cp as a unit, 1cp = 10-3Pa • S.
Viscosity: represents the measure of internal friction force during the flow of a liquid under the influence of gravity. The value is the ratio of the dynamic viscosity of the liquid to its density at the same temperature. It is in the unit of measurement in China's statutory unit of measurement in M2 / S. It is customary to use CST, 1cst = 1mm2 / S.
Enshi viscosity: Under specified conditions, the ratio of the time(s) required for a certain volume of specimen to flow out of a 200 mL test increase from a small hole in the Engler viscometer to the value of the water measured by the viscometer, expressed as 0Et.
Ray's viscosity: The time required for a sample of a certain volume to flow out of the Leidewude viscometer from a 50mL sample under specified conditions, in S.
Cecil viscosity: The time required for a sample of a given volume to flow out of the Saibote viscometer under specified conditions, in S. The Cess viscosity is divided into the Cess general viscosity(expressed in SUVs) and the Cess heavy oil viscosity(expressed in SFV).
III. Viscosity index
The viscosity index is a approximate quantitative value that represents the viscosity of the oil product with respect to temperature. The high viscosity index means that the viscosity of the oil product changes less with temperature, and vice versa.
Four, flash point
Under specified conditions, the lowest temperature at which a mixture of steam and air escaping from the heated oil product comes into contact with the flame is called a flash point and is expressed at °C. The determination method of flash point is divided into open cup method and closed cup method. The open cup method is used to determine the flash point of heavy lubricant; Closed cup method is used to determine the flash point of fuel and light lubricant.
Five, condensation point
The maximum temperature at which the test oil is cooled to stop moving under specified conditions is called the condensation point, expressed at °C. The condensation point is a project that evaluates the low temperature performance of oil products.
The condensation point of oil is directly related to the wax content. The more wax content in oil, the higher the condensation point. Therefore, the condensation point can guide the dewaxing process in the processing process of petroleum products.
Six, pour it.
The tipping point refers to the minimum temperature at which the cooled test oil energy flows under specified conditions, expressed at °C. Tilt points, like condensation points, are used to indicate the low temperature flow performance of petroleum products.
VII. Moisture
Water refers to the water content in the oil, expressed as a percentage of weight. There are several methods for measuring moisture in petroleum product analysis standards, generally expressed in %, less than 0.03 % is a trace. Specially required oils, their moisture is expressed as 10-6(ppm).
VIII. Mechanical impurities
All impurities present in the oil that are insoluble in the specified solvent are called mechanical impurities.
Water soluble acid or base
Water-soluble acid or base refers to the general term for acidic or alkaline substances that are soluble in water in oils.
10. Carbon
Under specified conditions, the residue formed by the oil during cracking is called residual charcoal. As a percentage of weight.
XI. Ash
The inorganic matter obtained by charring the residue of the oil under specified conditions is called ash, expressed as a percentage of weight. The ash is mainly cycloalkanes contained in the oil. Usually the ash content in the oil is very small. The ash content of the oil increases when some high ash additives are added to the oil.
XII. Emulsion value
The measure of the ability of the oil to separate from the oily emulsion is called the deemulsification value, expressed in min. It is a major specification item for steam turbine oil. Steamwheel oil is sometimes in contact with leakage, leakage, or even mixed to form temporary emulsification during use. Therefore, it must have the ability to quickly separate from water to ensure the normal circulation and lubrication of oil products.
XIII. Oxidation stability
The ability of petroleum products to resist the action of air(or oxygen) and maintain their nature without permanent changes is called the oxidation stability of oil products.
XIV. Shear stability
Shear stability is defined. Under conditions, the ability of petroleum products to resist shear effects to maintain viscosity related to the properties of the viscosity.
15, Chenggou point
The groove point is to store the test oil sample at a specified temperature of 18 H, cut the test oil into a groove with a metal sheet, and then determine whether the test oil flows together and covers the bottom of the test oil container within 10 S. If the oil sample flows back in 10s and completely covers the bottom of the test oil container, the oil sample is reported to be no groove; Conversely, the oil sample is reported as a groove. The groove forming point is to determine the groove forming performance of gear oil(low temperature).
XVI. Drip Point
The lowest temperature when a solid or semi-solid petroleum product under specified conditions reaches a certain degree of fluidity is called a drop point, expressed at °C.
The drop point of the grease has a great relationship with its composition. The general range of common grease drop points is as follows:
The drop point of hydrocarbon base grease is generally 40 ~ 80 °C
The drop point of calcium base fat is about 75 ~ 95 °C
The drop point of calcium sodium resin is about 120 ~ 135 °C
The drop point of sodium-based fat is about 130 ~ 200 °C
The drop point of the lithium-based resin is about 170 °C
XVII. Cone
At 25 °C, the depth at which the standard cone with a total load of 150 ± 0.25 g penetrates the grease sample vertically within 5s is called the lubricating resin taper, expressed as 1/10 mm.
The taper degree is an item that represents the softness and hardness of the grease. The larger the taper, the greater the consistency, the smaller the consistency, the softer the grease. On the contrary, the harder the grease, the greater the consistency. Most greases are semicolon based on taper size.
Free acids and free bases
Lubricating grease is made by thickening mineral oil with alkaline soap for animal and vegetable oils or full-blown fatty acids. If saponification is not complete or mineral oil is oxidized and decomposed, free acid will appear; If you use too much alkali, free alkali will appear at the high tip. The presence of too much free acid and alkali will cause corrosion of the parts. Therefore, the free acid and alkali of the grease should be controlled within a certain value.
XIX. Gelatin stability
Lubricating grease in use or long-term storage will have a small amount of oil discharged, this phenomenon is called oil. The ability of the grease to resist oil separation is called colloidal stability.
Mechanical stability
The mechanical stability of the grease, also known as shear stability, represents the ability of the grease to resist changes in consistency under mechanical working conditions. Under the long-term mechanical force, the viscosity of the grease will decrease. Under extremely harsh conditions, the structure of the grease will be destroyed and turned into a fluid, which will be lost from the lubrication site and lose the lubrication effect. This is because the fiber structure of the thickener, when subjected to long-term shear damage, makes the fiber shorter, resulting in a decrease in consistency. When slightly cut, the fiber can also be superimposed again to restore consistency. The mechanical shear performance is called the mechanical stability of the grease. |
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