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I. Introduction: Radar level gauges are favored by many industries primarily because this measurement method offers numerous advantages over other methods. Firstly, the radar level gauge features an integrated design; as a result, there is no wear and tear between its various mechanical components during use, allowing for a very long service life. Secondly, during the measurement process, the electromagnetic waves emitted by the antenna of the radar level gauge are not hindered by any medium as they travel, which enables timely measurement along with high precision. Once again, radar level gauges have a very large measurement range, which can reach over 30 meters, and they are suitable for measuring liquid levels under high temperature and pressure conditions. Finally, the antennas used in radar level gauges are made from high-quality materials with strong corrosion resistance, allowing them to function properly even in harsh environments. This article will introduce a case study on the use of our company’s radar level gauges in propylene gas tanks. Shanxi Huoja Industry currently has 2 propylene gas tanks, which are external floating roof tanks. The medium inside the tank is propylene gas. The external floating roof floats up and down depending on the amount of medium inside the tank. The level of the medium inside the tank is a very important parameter; it plays a crucial role in ensuring the smooth operation of the production process, improving production efficiency, and enhancing production safety. Due to the large range of gas tanks and the gaseous nature of the measured medium, level measurement in gas tanks has always been a challenging task. In the past, mechanical level measurement methods were used for monitoring the level in gas cylinders; these methods were complex to install, difficult to maintain, and did not provide accurate measurement data. For a long time, Huojia Industry has been striving to find an economical solution that offers a long service life, reliable performance, low maintenance requirements, and high measurement accuracy, in order to meet the needs of level measurement in gas tanks. After installing our company’s radar level gauge and observing its performance over several months, it was found that its measurement accuracy fully meets the requirements of the manufacturing process, thereby resolving the problem that had plagued them for many years. Taking our company’s DHE-RD-5100 radar level gauge as an example, this article introduces the application of radar level gauges in the propylene gas tanks at Huoja Industry. Made available for other users to reference. II. Current status of level gauges for gas holders Gas holder, gas tank. A container device used for storing various industrial gases, as well as for balancing the uneven demand for gases. They can be divided into two main categories: low-pressure gas tanks and high-pressure gas tanks. The former also has two structures: wet and dry. There are various materials. The level gauges commonly used for measuring the height of gas tanks are belt-type, with the steel belt connected to the top of the tank. Others can also be made into differential pressure transmitters, connected to the top of the gas tank using rubber hoses, with antifreeze filled inside ； There is also the blowing method for measurement ； Electrodes or trigger switches can also be installed at various positions along the travel of the gas tank. These measurement methods generally suffer from difficulties in installation, complex structures, high costs, numerous sources of measurement error, and their actual performance is not very satisfactory. Original installation diagram of the steel strip level gauge. III. Measurement principle and feasible improvement methods and measures. Our DHE-RD-5100 radar level gauge is a contactless radar level gauge designed specifically for measuring solids. As shown in the figure below: Schematic diagram of DHE-RD-5100 radar installation. We install the radar on a bracket at the top of the tank, using universal flanges for connection, with the parabolic antenna aligned toward the external floating roof. After the gauge is in operation, the height between the gauge and the floating roof can be measured. The actual height of the gas inside the tank can be calculated by subtracting the measured height and the height of the floating roof itself from the total height. Since the external floating roof is generally curved, adjust the universal flange to make the horn antenna as vertical as possible with respect to the surface of the floating roof, while simultaneously observing the echo signal to determine the angle at which the echo signal is strongest. Enable the echo signal tracking function at the same time; since the external floating roof experiences severe vibrations during feeding, excessive vibrations can easily lead to signal loss. Once the echo signal tracking function is enabled, the instrument will continuously track the detected echo signals. Installation notes: 1. Try to install the radar above the flat area of the floating roof to avoid false reflections ； 2. The level gauge should not be installed at the center of an arched tank, as this can cause false readings due to enhanced reflections; it also shouldn’t be placed too close to the tank walls. The optimal installation location is at 1/2 of the container’s radius ； Results achieved: Through the above improvements, **the maintenance interval for the instruments by the maintenance staff has been extended, while the stable operation of level measurement has been ensured. This further improved the accuracy of level measurement, laying a foundation for the normal operation of the gas holder. Installation photos at the event site