The normal operation of the appearance is inseparable from the protection of the site, especially some important process links, once there is a leak, it will greatly affect the quality of the product, resulting in heavy losses.
First of all, the remote transmission and field indication type of liquid level gauge will be installed together on the important tank, and the most intuitive way to see and judge the appearance of the liquid level in this situation is to compare with the local level gauge on site, because the structure of the local level gauge is purely mechanical, and the reliability is extremely high, so the investigation of the appearance value of the appearance and the trend of the liquid level change is common with the grounding level gauge can basically judge whether the radar level gauge is operating normally.
When the number of indicators suddenly increases, shakes violently or insists on the dead line for a long time, the process parameters can be adjusted according to the situation to detect whether the appearance function is normal, and whether there is a problem can be roughly identified.
If the level indicator insists on an alarm, maximum or minimum value, the transmitter should be checked first. If the transmitter is normal, it can be identified as having a problem with the apparent appearance. When the output of the transmitter is basically the same as the display of the DCS, the level control system can be changed to manual operation, the opening of the control valve can be changed, and the change of the liquid level can be investigated.
When the process liquid level is changed, there is no output on the surface, the liquid level is the smallest, and the liquid level is the largest, the transmitter and the appearance or DCS card connection status should be checked. Together, the balance container is inspected. Check to see if the condensate and isolation fluid have been washed away. Check whether there is fouling and water droplets in the radar level gauge transmitting antenna and its surroundings. This phenomenon prevents microwaves from being transmitted to the actual level. Disturbances can usually be ruled out by a brief wipe.
When the liquid level is displayed or the recorded curve fluctuates large and fast, it may be caused by improper PID parameter setting. The damping setting of the transmitter is improper, and the sampling valve and pressure pipe leakage, which will cause the liquid level to fluctuate.
However, it is necessary to pay attention to the fact that the level gauge is attributed to the principle of echo difference ranging, and the change rate of its parameters is related to the actual condition of the measurement environment, which needs to be judged according to the certain experience, for example, the level of the boiler drum changes quickly, and the level change of the liquid storage tank is relatively slow. The liquid level suddenly shows a large change and shake, the maximum or the smallest appear, and there is a high possibility of appearance problems.
The most feared thing about liquid level measurement is the presentation of false liquid level. When a false level phenomenon is suspected, it is necessary to calmly discriminate; Switch the control system to manual operation, view or calibrate the transmitters and systems, and see if there are problems with the pressure lines and valves until they are identified.
When the liquid level is low, the float level gauge should check whether there is sediment in the main pipe, otherwise it should be purged with drainage. The buoy level gauge flushes the buildup on the buoy by draining it to see if there is any blockage. The blowing level gauge should check whether there is any leakage in the air source line.
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