Instruments: [One Question per Week] Third Week of 2011
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Instruments: [Weekly Question] Question for the third week of 2011: This week, we will discuss practical experience in the field application of level gauges. The format for posting should be as follows: Operating conditions: medium, temperature, operating pressure, etc； Type of level gauge used: such as float level gauges, etc ； Usage scenarios, technical challenges, maintenance methods, etc ； Empirical summary: Using AAA to measure the BBB boundary poses CCC issues; if DDD is used to measure the EEEEEE boundary... Note: 1) Respondents can receive up to 20 wealth rewards, and only responses that involve in-depth discussion will earn extra points! In principle, not more than 120 ； 2) Thank you all for your active participation ；
When the plant was built, Shanghai-made steel-band float level gauges were used for measuring the levels in the 12 storage tanks for raw materials. After some time of use, various problems began to arise, such as broken steel cables, jammed digital displays for level measurement, detached floats, and air leaks in the floats, all of which caused significant errors in measurements. Instrument technicians had to check these steel-band float level gauges from time to time, and a major repair was required each year; even so, normal operation could not be fully guaranteed. During the project renovation in 2004, these dozen or so steel-band float level gauges were completely replaced with E+H steel-cable guided-wave radar level gauges (model FMP40-AAA2ALJF21CA), which solved all the problems. Since their installation in 2004, these 12 guided-wave radar level gauges have not experienced any major issues; they offer high measurement accuracy, and there is almost no need for routine maintenance.
A K-tek magnetostrictive level gauge is used to measure the interface of the epichlorohydrin/dichloropropanol aqueous solution. Temperature: 40 degrees. Density: 1.18/1.104. Operating pressure: atmospheric pressure. Performance: Once adjusted, it requires little maintenance; when the medium is dirty, it is necessary to clean the oil adhering to the float and probe.
Application conditions: Catalytic acidic gas separation tank, at normal temperature and 200 Kpa. Type of level gauge used: Guided wave radar, float level gauge. Usage aspects: Guided wave radars require almost no maintenance, while float level gauges need to be adjusted frequently. Two issues arise: zero-point drift and crystallization. Handling these situations is dirty and dangerous, as it involves acidic gases containing sulfur. A colleague once inhaled such gases deeply by accident, which caused dizziness and temporary confusion; he almost fell over the railing of the platform. Upon arriving at the scene, his clothes and body had a very strong foul odor. Sometimes, the float gauge heads are taken back to the calibration laboratory for calibration using a weight method; just desalination takes some time, and pressure transducers need to be replaced frequently.
Medium: 1,3-butadiene and sodium sulfite. Operating pressure: 0.8–1.0 mpag. Operating temperature: 25 degrees. Operating density: 620/1150. Measurement range: 0–1500 mm. Instrument selected: 3051CD2A22A1AB4M5I5S2. Capillary filling material: MFR.STD. Capillary length: 3 m. Incomplete measurements occur at the beginning of operation due to the instability of the medium. No problems have occurred since it stabilized. This interface is involved in control.
Operating conditions of the application: Crude oil. Type of level gauge used: Multifunctional level meter. Applications: It can provide information on the interface level, oil-water thickness, water content, etc. Empirical findings: Under stable operating conditions, it performs well at present
We don’t have any instruments for measuring boundary positions here, so our understanding of boundary meters is only conceptual; I hope you can reply and let us know what the answer is
Moderator: If the container is filled to capacity, can a regular differential pressure transmitter be used to measure the level?
When our facility first started operating, ordinary differential pressure transmitters were used; now we have switched to EJA double-flange transmitters. Since the medium contains impurities, blockages can occur under positive pressure. After making this change, the results have been good. The medium in our facility is water at 220 degrees and 25 kilograms per square centimeter
Operating conditions of the application: various types of high tanks. Operating conditions of the application: radar, ultrasonic level gauges