What should we pay attention to when measuring the flash point of hydraulic insulation oil
2018/5/15 Viewers:
When determining the flash point of hydraulic insulating oil, we should pay attention to the following items in addition to strictly following the steps required in the regulations.
(1) in the determination of the amount of oil added to the oil cup, it should be just to the marking line, otherwise the oil quantity will be measured too low, the oil quantity will be small and the result will be high. Because the amount of oil will affect the air volume above the liquid level, that is, the concentration of oil vapor and air mixture, which will also affect the high or low flash point.
(2) attention should be paid to the size of the flame used for ignition, the height of the liquid surface of the flame and the average retention time on the liquid surface. The larger the general flame is, the closer the flame is from the liquid surface and the longer the time of moving on the liquid surface, the result is low. On the contrary, the result is higher than the normal value.
(3) heating speed should be strictly controlled according to regulations, not too fast or too slow. If the heating is too fast, the evaporation speed of the oil is fast, so that the oil vapor concentration in the air reaches the lower limit of explosion in advance, and the result is low. If the heating rate is too slow, the measurement time is longer, the number of ignition is more, some oil vapour is lost, and the mixture of oil and steam and air is postponed to the time of the flash point, and the result is high.
(4) if the oil contains water, it must be dehydrated before determining the flash point. Because when the oil is heated, the water dispersed in the oil will be vaporized to form water vapor, or sometimes the formation of bubbles on the liquid surface, which affects the normal gasification of the oil, postpones the flash time and makes the result of the measurement high. When heavy oil is more moisture, flash point is measured with open cup. When heated to a certain temperature, water in the oil will form foam, so it is easy to overflow the cup, so that the test can not be carried out.
(5) in the ignition process, we should first look at the temperature and then ignite. Because the oil temperature will rise after ignition, not the original flash temperature, and the result is higher.
(6) in relation to the establishment of pressure, the general pressure is high flash point high, otherwise otherwise. Therefore, when measuring flash point, the correction should be made according to the local air pressure.
(7) the flash point is related to the form of the detector used only. The results usually measured by the flash point tester are higher than those measured by the closed flash point apparatus. This is because the oil vapor formed in the open flash instrument can be freely extended to the surrounding air, causing some oil vapors to be lost.
(1) in the determination of the amount of oil added to the oil cup, it should be just to the marking line, otherwise the oil quantity will be measured too low, the oil quantity will be small and the result will be high. Because the amount of oil will affect the air volume above the liquid level, that is, the concentration of oil vapor and air mixture, which will also affect the high or low flash point.
(2) attention should be paid to the size of the flame used for ignition, the height of the liquid surface of the flame and the average retention time on the liquid surface. The larger the general flame is, the closer the flame is from the liquid surface and the longer the time of moving on the liquid surface, the result is low. On the contrary, the result is higher than the normal value.
(3) heating speed should be strictly controlled according to regulations, not too fast or too slow. If the heating is too fast, the evaporation speed of the oil is fast, so that the oil vapor concentration in the air reaches the lower limit of explosion in advance, and the result is low. If the heating rate is too slow, the measurement time is longer, the number of ignition is more, some oil vapour is lost, and the mixture of oil and steam and air is postponed to the time of the flash point, and the result is high.
(4) if the oil contains water, it must be dehydrated before determining the flash point. Because when the oil is heated, the water dispersed in the oil will be vaporized to form water vapor, or sometimes the formation of bubbles on the liquid surface, which affects the normal gasification of the oil, postpones the flash time and makes the result of the measurement high. When heavy oil is more moisture, flash point is measured with open cup. When heated to a certain temperature, water in the oil will form foam, so it is easy to overflow the cup, so that the test can not be carried out.
(5) in the ignition process, we should first look at the temperature and then ignite. Because the oil temperature will rise after ignition, not the original flash temperature, and the result is higher.
(6) in relation to the establishment of pressure, the general pressure is high flash point high, otherwise otherwise. Therefore, when measuring flash point, the correction should be made according to the local air pressure.
(7) the flash point is related to the form of the detector used only. The results usually measured by the flash point tester are higher than those measured by the closed flash point apparatus. This is because the oil vapor formed in the open flash instrument can be freely extended to the surrounding air, causing some oil vapors to be lost.
- Pre：The significance of flash poin 2018/5/15
- Next： The factors that affect the f 2018/5/15