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A brief analysis of the causes of measurement errors in boiler drum water level I. Factors affecting drum water level measurement Based on an analysis of several methods for measuring water level, the main factors that affect such measurements are as follows: 1. The installation conditions, location, and environment of the water level gauge play a role; the positioning error of these gauges is generally between 10 and 50 mm. The environment in which each gauge is located varies, which affects heat dissipation； 2. The influence of the conditions under which the drum is installed: the levelness requirement when installing the drum should be ≤5 mm, but after the boiler has been in operation for several years, this value increases to 15–20 mm. The water level gauge is installed with reference to the centerline of the drum, which results in errors in its installation ； 3. Regarding the impact of water entering the steam drum from the feedwater and water wall, the feedwater temperature cannot remain constant due to the influence of various heating conditions, and it is lower than the saturation temperature at the corresponding pressure ； The water entering the water wall contains a large number of bubbles, which continuously evaporate; as a result, its density is lower than that of water at the corresponding temperature and pressure ； 4. The effect of the downcomer: During boiler operation, water in the drum continuously flows into the downcomer at high speed, resulting in the water level in the drum not being at an ideal level. This level varies depending on the position of the downcomer, with differences that can range from 40 to 60 mm ； 5. Inherent errors of the measuring instrument itself: although the accuracy of the instrument is very high, measurement and installation errors still exist. II. Methods and measures to reduce measurement errors of the drum water level 1. The sampling location should be above the set value for water level protection, with a certain margin ； 2. An appropriate diameter for the sampling pipeline, in order to reduce flow resistance and prevent delays in water level display ； 3. Try to shorten the length of the connecting pipes to reduce flow resistance and increase the temperature of the medium inside them. The horizontal section before the container should be long enough to facilitate the condensation of vapor ； 4. Install a connecting pipe between the soda water sampling pipes as a damper to mitigate the impact of large fluctuations in the water level of the drum on water level measurement ； 5. Each level gauge should have independent sampling holes, sampling pipelines, and balance containers to avoid interference between them ； 6. The steam-side sampling tube is inclined toward the drum to facilitate the return flow of condensed water, ensuring a constant water level in the balance vessel ； 7. Proper insulation of the piping ensures both the maintenance of the medium’s temperature and effective heat dissipation.