Scope of application
The petroleum product movement tester is designed and manufactured according to the national standard GB/T265. It is used to measure the kinematic viscosity of liquid petroleum products. LCD screen Chinese display, man-machine dialogue interface, preset temperature, test time and other parameters menu prompt input, appearance design is beautiful, is the introduction of new instruments.
Viscosity is one of the main indexes of petroleum products, and viscosity is one of the important factors that affect the biodegradability of base oils. Many domestic lubricants are classified and classified according to their kinematic viscosity of 40oC and 100oC. In practical application, viscosity is an important index to evaluate the flow performance of lubricating oil. It is important for quality identification of petroleum products and their application. Viscosity is large, oil film thickness is large, lubrication performance is good, but the viscosity is too large, will increase the friction resistance, waste of resources.
Kinematic viscosity is the ratio of the dynamic viscosity of a liquid to its density at the same temperature. It represents a measure of the friction of a liquid when it flows under gravity. Kinematic viscosity measurement is the determination of the time at which a certain volume of liquid passes through a calibrated glass capillary viscometer at a constant temperature. The product of the capillary constant and flow time, i.e., the kinematic viscosity of the liquid at this temperature.
Functional characteristics
1. ring type fluorescent lamp illumination, fluoroscopy is good. Easily observed.
2. heater and guide tube and bath parts are made of stainless steel, durable and durable.
3. Automatically calculate the capillary constant and the average product of the test time. The temperature control precision is high and the accuracy is good.
4, computer temperature control, timing, constant temperature, water bath and other parts. Constant temperature bath is small cylinder, round cylinder, double layer, uniform temperature distribution in the bath, the temperature control effect is good.
5. Chinese LCD screen display, man-machine interface, the preset temperature, test time and other parameters, menu input, actuator adopts advanced SSR, its features of no contact, no spark, no action noise, vibration resistance, long life.
Technical parameter:
1, weight: 25kg
2, constant temperature accuracy: + 0.1
3, the number of cards installed capillary: 3 branches
4 ,heater power: 1000W
5, environmental temperature: room temperature to 35 degrees
6, temperature control settings: room temperature to 100 degrees set at any time
7, work power supply: 220V + 10% 50Hz
The main factors influencing the determination of kinematic viscosity:
First, the measurement of the factors:
1. Stopwatch: The stopwatch is used to determine the time the sample flows through the viscometer. If the stopwatch is not precise enough, it may cause a test error. Therefore, for the use of the stopwatch, be sure to regularly test.
2. viscometer coefficient: capillary viscometer must be calibrated on a regular basis, otherwise it will cause a greater error.
Second, the experimental operation of the factors
Second, the experimental operation of the factors
1, the viscosity of the process of measuring the flow of oil through the viscometer
The flow time of the specimen must be within the specified range. GB / T265 provides that the flow time to> 200S. Mainly in order to ensure that the oil flow in the viscometer for the laminar flow. If the oil flow rate is too fast beyond the specified range, will become turbulent, with turbulence can not use the cassace equation to calculate the viscosity of oil. In addition, the flow rate is too fast, the reading error will increase accordingly. If the oil flow rate is too slow, within a specified time is not easy to maintain constant temperature
2, the viscosity of the test process bath temperature accuracy
Determination of kinematic viscosity to be strictly in accordance with the provisions of constant temperature test, which is the determination of oil moving viscosity of one of the important conditions. In GB / T265, the temperature control accuracy of the thermostatic bath must be ± 1oC, while in the ASTMD445 bath temperature control accuracy of ± 0.5oC. Because the viscosity of the oil sample decreases with increasing temperature and increases with the temperature drop, it must be strictly in accordance with the specified constant temperature, the slight temperature deviation will make the viscosity measurement results have a greater error.
Third, the viscosity of the other factors in the determination process
Test oil samples containing impurities, moisture and capillary viscometer is not washed, will also affect the sample in the capillary viscometer in the normal flow, the results are high. The solvent used for the washing in the viscometer is not dry and the sample is diluted so that the result is low.
When measuring the viscosity of the oil, the sample in the viscometer can not have air bubbles. If the oil bubbles will affect the oil volume, while entering the capillary will form a gas plug, so that the flow resistance of oil increased, the determination of high results.
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