Briefly explain the reasons for the red and white colors appearing in magnetic flap level gauges and the solutions to address this issue

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This post was last edited by yuchenchf on 2017-5-2 at 14:10. A common fault that occurs in magnetic flap level gauges during use is the appearance of red and white colors on the flaps. Based on years of experience, several possible causes can be identified: issues with the external panel, such as dust accumulating in the gaps between the magnetic flaps over time, loss of magnetism in those flaps, or panel distortion due to vibrations at the installation site; these factors can cause the axes of some flaps to shift or become misaligned, resulting in excessive friction that prevents them from flipping in sync with the internal float. This phenomenon is particularly common when there are problems with the external panel that lead to high friction on the flaps. In a jacketed magnetic flap level gauge, the float inside experiences intermittent sticking due to internal dirt; when it gets stuck at one liquid level, the rising liquid level eventually submerges the float, after which the float suddenly breaks free from the stuck position. This causes the external panel to fail to respond in time, resulting in a red-white-red-white pattern. If the float is covered with a large amount of impurities, it will get stuck in multiple places, and this will be reflected on the external panel as multiple segments of red and white colors. The reduced magnetism of the internal float, combined with increased friction from the rotation of the external ball, can also cause the panel to display colors in multiple segments. Additionally, the material used to secure the panel plays a role here; in many cases, wire is used for fixing the magnetic ball during maintenance or to insulate it, and over time this wire becomes magnetic, resulting in abnormal magnetism in the area surrounding it and causing the panel to show colors in multiple segments. It is more likely due to demagnetization of the flip plate caused by prolonged use. It means the magnetic force between the float and the flip column is not matched. Therefore, instrumentation products must be installed in strict accordance with the specifications provided by the manufacturer from the very beginning; many failures occur as a result of improper installation or incorrect operation. The following requirements should be noted regarding the installation of magnetic flip valves: 1. Specific requirements for the installation of jacketed magnetic flip valve level gauges: (1) If the measurement range of the magnetic flip valve level gauge exceeds 4.5 meters, an intermediate support should be added between the upper and lower flanges. ⑵The level gauge must be installed vertically, with a deviation of ≤3mm. ⑶There must be no magnetically attractive obstacles within a 100mm distance of the cylinder. ⑷In addition to being installed in accordance with the above requirements, insulated level gauges must also be connected to a cooling or heating system. ⑸After carefully checking that the bolts at all connections are tightened, the instrument can be put into use. ⑹When installing the float in the cylinder, be sure not to turn the buoy upside down (with the magnetic end on top). ⑺For underground level gauges, the conduit is first installed inside an underground container; thereafter, the connected float, buoy, and linkage are placed into the conduit, and finally the upper part is installed. The following steps must be followed during use: (1) Before leaving the factory, all components of the level gauge have been tested for internal and external pressure in accordance with standards; therefore, no further pressure testing is required after installation. When performing an internal pressure test after connecting the container to the level gauge, the float should be removed, and it should be reinserted once operation begins. ⑵When putting a magnetic flap level gauge into operation, the upper valve should be opened first, followed by the slow opening of the lower valve. It is necessary to avoid rapid inflow of the pressurized medium in the container into the pipe, which could cause the float to rise quickly, leading to malfunction in the flap’s tracking function or damage to the float as a result of the shock. ⑶During use, if individual flip columns fail to flip due to sudden changes in liquid level or other reasons, they can be adjusted using correction magnets (included) or floats.