危害greaseMany elements of flash point determination:

    1, grease commonly used instruments and equipment, the results measured by the general open flash point tester are always higher than the results measured by the closed acne flash point, which is because the steam generated by the open flash point tester can spread freely into the air, so that a small part of the steam is damaged。

    2, the sample moisture content, the sample moisture content must be carried out dedrying, you can carry out flash point determination。The water content of the sample is not more than 0 for the flash point determination of the closed-mouth acne cup.05%, open-cup flash point method requires that the water content of the sample does not exceed 0.1%。 Otherwise, it must be dried, this is because when the oil is heated, the water dispersed in the grease will vaporize to produce water vapor, and sometimes the steam bubble will be covered on the liquid level, endangering the conventional vaporization of the finished oil and delaying the flash time。Overtest the result。When the flash point of the fuel oil with more water is measured by the open-mouth cup method, the sample is easy to spill the oil mark when the water is heated to the corresponding temperature, so that the test cannot be carried out。

    3. Sample size，The amount of grease in the oil test must meet the requirements，The sample in the cup must be fitted to the ring scale as required，Filling too much or too little will change the indoor space capacity above the liquid level，Thus endangering the concentration of oil vapor and gas compounds，Make the measured flash point slightly lower or higher，There is a lot of oil in the cup of the closed-mouth acne flashpoint tester，Low measured flash point;Little remaining oil，The measured flash point is higher than normal。

    4. Heating rate，The heating rate of the grease is too fast，Rapid sample volatilization，Will make the switch valve partial concentration value to the lower explosive limit and flash early，Resulting in slightly lower measurement results，The heating rate is too slow，Measurement time increment，The frequency of ignition increases，A small amount of oil vapor is lost，Delay the time for oil vapor and gas compounds to reach the flash point concentration value，Raise the temperature to the lower explosive limit。The measured result is too high, so the heating rate must be strictly controlled according to the specification。

    5, atmospheric pressure, the flash point of the grease is related to environmental pressure。Low pressure oil is volatile, so the lower the measured flash point, the higher the flash point, the specification requires 101.The flash point measured at atmospheric pressure in 3kpa is the flash point measured at normal working pressure. If atmospheric pressure is offset, the measured flash point needs to be adjusted by atmospheric pressure。

    6、Industrial greaseThe ignition control, the diameter of the ball flame, the distance between the liquid level and the sample and the residence time need to be strictly implemented in accordance with the national industry standards。If the diameter of the spherical flame is large, the distance between it and the liquid level is close, and the residence time is too long, the measured result will be slightly lower, on the contrary, it is higher than the conventional one。