The flash point tester can be applied to various types of oil products, including crude oil, gasoline, diesel, kerosene, lubricating oil, transformer oil, etc. Whether it is light and volatile oil products, or heavy and viscous oil products, accurate flash point determination can be carried out by selecting suitable flash point testers (open or closed) and corresponding testing parameters, meeting the needs of various oil product testing in the petroleum industry and related fields.

The flash point tester can be divided into two types: closed and open, with different working principles:

1. Principle of closed flash point tester

It mainly involves filling a small amount of oil sample into an oil cup and covering it with a metal mesh with a specified aperture, then continuously heating the oil sample at a certain rate, while stirring to evenly heat the oil product. As the temperature increases, the oil will evaporate and produce vapor. An ignition source (such as an electric spark generated by an electronic igniter) will be introduced through a small hole above the oil cup. If a flashing phenomenon occurs at this time, the corresponding oil temperature is the closed flash point. Throughout the process, the oil sample had relatively limited contact with the outside air, which is more in line with the actual situation of some volatile and light oil products in relatively enclosed environments, such as measuring the flash point of gasoline.

2. Principle of open flash point tester

Pour the oil sample into an open container such as a crucible, slowly heat the oil sample, and continuously use a specified flame (such as a standard ignition source) close to the oil surface. The open flash point is the temperature at which the vapor concentration above the oil surface can be ignited by an external fire source and briefly flash. The open flash point measurement is suitable for heavy oil products, as these products are relatively non-volatile and can more accurately reflect their flash point when in contact with air during actual storage and use in an open environment. For example, open flash point measuring instruments are often used to measure lubricating oils.

Precautions for using a closed flash point tester:

-The instrument should be placed on a flat, clean, and dust-free surface to avoid air flow and vibration.

-The ambient temperature should be controlled between 0 ℃ and 40 ℃, the humidity should be ≤ 85RH, and there should be no corrosive gases or electromagnetic interference.

-Ensure that the power cord is kept away from high temperatures or friction objects, and use a power socket with reliable grounding.

-During the testing process, there is high heat in the oil cup and its vicinity. Do not touch it.

-After the test is completed, if the sample burns, cover the oil cup with an oil cup lid in a timely manner. The oil cup lid has high heat and should not be touched.

-Do not manually operate the ignition scraper, otherwise it may cause damage to the instrument.

-Although the closed flash point tester has automatic ignition and cooling functions, safety regulations must still be strictly followed during operation. Ensure that there are no flammable substances in the testing area and that the ventilation system of the instrument is functioning properly to prevent the occurrence of fire accidents.

-The sample should avoid impurities and the liquid level should not exceed 80% of the total container volume.

-When replacing the sample, the oil cup must be cleaned thoroughly.

-The sample needs to ensure good container sealing before testing to avoid air pollution. Operators should use containers that meet the standards to avoid testing errors caused by container issues.

-Regularly clean the instrument to ensure that components such as sensors and detection rings are free of oil and impurities.

-If the instrument displays a deviation between the ambient temperature and the calibrated thermometer, the temperature sensor needs to be cleaned.

-The Pt100 temperature sensor should be calibrated once a year.

-Check the electrical connections of the ignition system to ensure its proper functioning.