Steam generator maintenance methods and cycles
Some problems will occur if the steam generator is used for too long. Therefore, we need to pay attention to the corresponding maintenance work when using the steam generator in daily life. Today, let’s talk with you about the daily maintenance methods and maintenance cycles of steam generators.
1. Routine maintenance of steam generator
1.Water level gauge
Rinse the water level meter at least once per shift to keep the water level glass plate clean, ensure that the visible part of the water level meter is clear, and the water level is correct and reliable. If the glass gasket is leaking water or steam, tighten or replace the filler in time.
⒉Water level in the pot
It is realized by the automatic water supply control system, and the water level control adopts an electrode structure. The sensitivity and reliability of water level control should be checked regularly.
3. Pressure controller
The sensitivity and reliability of the pressure controller should be checked regularly.
4. Pressure gauge
Whether the pressure gauge is working properly should be checked regularly. If the pressure gauge is found to be damaged or malfunctioning, the furnace should be shut down immediately for repair or replacement. To ensure the accuracy of the pressure gauge, it should be calibrated at least once every six months.
5. Sewage discharge
Generally, the feed water contains a variety of minerals. After the feed water enters the steam generator and is heated and vaporized, these substances will precipitate. When the boiler water is concentrated to a certain extent, these substances will settle in the pot and form scale. The greater the evaporation, the greater the evaporation. The longer the operation continues, the more sediment builds up. In order to prevent steam generator accidents caused by scale and slag, the water supply quality must be ensured and the alkalinity of the boiler water must be reduced; usually when the alkalinity of the boiler water is greater than 20 mg equivalent/liter, sewage should be discharged.
2. Steam generator maintenance cycle
1. Discharge sewage every day
The steam generator needs to be drained every day, and each blowdown needs to be lowered below the water level of the steam generator.
2. After the equipment runs for 2-3 weeks, the following aspects should be maintained:
a. Carry out comprehensive inspection and measurement of automatic control system equipment and instruments. Important detection instruments and automatic control equipment such as water level and pressure must work normally;
b. Check the convection pipe bundle and energy saver, and remove any dust accumulation if there is any. If there is no dust accumulation, the inspection time can be extended to once a month. If there is still no dust accumulation, the inspection can be extended to once every 2 to 3 months. At the same time, check whether there is any leakage at the welding joint of the pipe end. If there is leakage, it should be repaired in time;
c. Check whether the oil level of the drum and induced draft fan bearing seat is normal, and the cooling water pipe should be smooth;
d. If there is leakage in water level gauges, valves, pipe flanges, etc., they should be repaired.
3. After every 3 to 6 months of operation of the steam generator, the boiler should be shut down for comprehensive inspection and maintenance. In addition to the above work, the following steam generator maintenance work is also required:
a. Electrode-type water level controllers should clean the water level electrodes, and pressure gauges that have been used for 6 months should be recalibrated;
b. Open the top cover of the economizer and condenser, remove the dust accumulated outside the tubes, remove the elbows, and remove the internal dirt;
c. Remove the scale and sludge inside the drum, the water-cooled wall tube and the header box, wash with clean water, and remove the soot and furnace ash on the water-cooled wall and the fire surface of the drum;
d. Check the inside and outside of the steam generator, such as the welds of the pressure-bearing parts and whether there is any corrosion on the inside and outside of the steel plates. If defects are found, they should be repaired immediately. If the defect is not serious, it can be left to be repaired during the next shutdown of the furnace. If anything suspicious is found but does not affect production safety, a record should be made for future reference;
e. Check whether the rolling bearing of the induced draft fan is normal and the degree of wear of the impeller and shell;
f. If necessary, remove the furnace wall, outer shell, insulation layer, etc. for thorough inspection. If any serious damage is found, it must be repaired before continued use. At the same time, the inspection results and repair status should be filled in the steam generator safety technical registration book.
4. If the steam generator has been running for more than one year, the following steam generator maintenance work should be performed:
a. Conduct comprehensive inspection and performance testing of fuel delivery system equipment and burners. Check the working performance of the valves and instruments of the fuel delivery pipeline and test the reliability of the fuel cut-off device.
b. Conduct comprehensive testing and maintenance of the accuracy and reliability of all automatic control system equipment and instruments. Carry out action tests and tests of each interlocking device.
C. Perform performance testing, repair or replacement of pressure gauges, safety valves, water level gauges, blowdown valves, steam valves, etc.
d. Carry out inspection, maintenance and painting of equipment appearance.