Measurement and Calculation of Water Level in Primary Circuit of Nuclear Power Plant

Abstract: The information on the water level measurement and calculation of the primary loop regulator of the nuclear power plant is provided by the excellent manufacturers of flowmeters and flowmeters. 1. Regulator water level control and protection The nuclear power plant regulator is an important equipment in the nuclear reactor coolant system (RCP). It maintains the normal RCP pressure during steady-state operation, and limits the RCP pressure to the allowable value during transient state. Inside. In addition, the voltage regulator also acts as. More flowmeter manufacturers choose models and price quotations. You are welcome to inquire. The following is the details of the water level measurement and calculation of the primary loop regulator of the nuclear power plant. 1. Regulator water level control and protection The nuclear power plant regulator is an important equipment in the nuclear reactor coolant system (RCP). It maintains the normal RCP pressure during steady-state operation, and limits the RCP pressure to the allowable value during transient state. Inside. In addition, the regulator also acts as a buffer tank for the reactor coolant, ensuring that the primary circuit is full of water. At rated power, about 60 rings in the regulator are saturated water, 40% are saturated steam, and the bottom of the regulator (liquid area) is connected to the heat pipe section of a loop of RCP through a wave tube. The RCP is a water-filled system and the pressure in the regulator will be transmitted throughout the RCP. The water level of the regulator should not be too high or too low, otherwise it will cause the failure of the pressure regulation or the exposed burnt of the electric heater. The main factors that lead to the change of the water level of the pressurizer are: (1) the change of the load changes the average temperature of the reactor coolant, which causes the change of the coolant volume; (2) the unbalance between the charging flow and the discharge flow of the pressurizer (such as opening the discharge orifice, coolant leakage and starting the second charging pump, etc.). The function of the regulator water level control protection system is to adjust the water level of the regulator near the set value to ensure that the operating conditions of the regulator can meet the needs of pressure control, and to protect the safety of the equipment. The regulator water level transmitter not only plays the role of measuring and monitoring the water level, but also used for the water level control and protection of the regulator. The simulation diagram of the water level control protection of the voltage stabilizer is shown in Figure 1. As can be seen from Figure 1, the water level of the voltage stabilizer is measured simultaneously by three independent 6000 series nuclear-level differential pressure water level transmitters (0llMN, 008MN, 007MN), and the measurement signals are sent to three independent SIP protection cabinets in the electrical room. (SIP1 group, SIP2 group, SIP3 group) for data conversion, the (4~20) mA current signal is converted into (1~5) VDC voltage signal through the converter (RS), and the three voltage signals are divided into two channels. All the way to the threshold relay (XU), after the logic processing unit performs a three-out-of-two logic operation, a voltage stabilizer high water level nuclear reactor trip signal is generated. The other way goes to the selector switch (444CC), and the regulator (404RG) controls the upper-fill water regulating valve to adjust the water level of the regulator. It can be seen that the three water level measurement signals are not only involved in the regulator water level adjustment, but also in the nuclear reactor trip logic protection. Therefore, the accurate measurement of the three water level transmitters is very important for the regulator water level adjustment and water level protection. effect. 2. Measurement and calculation of the water level of the voltage stabilizer Figure 2 is the installation diagram of the water level measurement of the voltage stabilizer. One side of the differential pressure transmitter is connected to the lower nozzle of the regulator, which reflects the pressure generated by the water level, and the other side is connected to a reference liquid capillary. The upper end of the reference liquid capillary is connected to the gas space of the regulator through a condensation tank. A diaphragm separates the water in the reference liquid capillary from the condensing tank to prevent the hydrogen gas separated from the regulator water from forming bubbles into the reference liquid capillary and affecting its measurement accuracy. In the regulator, the two phases of steam and water coexist and are in a saturated state. Taking the pressure regulator water level measuring transmitter as an example, calculate the differential pressure value of 007MN at O ​​and 100% water level under full power and stable operating conditions, and the need to add to the transmitter to verify the 007MN during shutdown and refueling maintenance. differential pressure value of the device. Assuming that the ambient temperature during calibration is 25°C, the pressure value of 007MN at O ​​and 100% water level can be calculated according to the data marked in Figure 2 and the given known data. Under the condition of full power and stable operation, the absolute pressure of the voltage stabilizer is 15.5MPa, and the corresponding saturation temperature is 344℃. The saturated water density of the regulator at this pressure and temperatureρ3=0.59395×lO3kg/m3, saturated steam densityρ3=0.10l9×1O3kg/m3. In addition, the positive and negative pressure sides of the pressure taking tube are far away from the body of the regulator, and the actual temperature of the pressure taking tube is close to the ambient temperature of 30 °C, so the pressure regulator is under the absolute pressure of 15.5MPa, the positive and negative pressure side of the pressure taking tube at the end The saturated water density should beρ1=ρ2=ρ5=1.002×l03. Calculation of the differential pressure experienced by the 007MN at O ​​and 100% water level at full power at one atmosphere. At 0 water level (4mA): △P0=P+-P_=[ρ3g (L3+L4)+ρ5gL5]-(ρ1gL1+ρ2gL2) in the formula, P+ is the pressure on the positive pressure side of 007MN, Pa; P_ is the pressure on the negative pressure side of 007MN, Pa; △P0 is the 0 water level differential pressure, Pa; g is the acceleration of gravity. △P0=0.10l9×lO3×9.8×(O.013+9.765) X 1.0O2×1O3×9.8×1.938-1.0O2×lO3×9.8×0.341-1.002×1O3×9.8×11.375=-86251.54 at 100% water level (2OmA): △P100%=P+-P_=(ρ3gL3 tenρ4gL4 tenρ5gL5)-(ρ1gL1 tenρ2gL2)=0.10l9×lO3×9.8×0.013 ten 0.59395×103×9.8×9.765+1.002×103×9.8×1.938-1.002×1O3×9.8×0,341-1.002×1O3×9.8×11.375=-39163.83 where △P100% is 100% water level differential pressure, Pa.

If you have plenty of time, you can learn how to take care of v shape coriolis mass flow meter. Also, invest in the right endress hauser ultrasonic flow meter mass flow meter.

So, get ready to dazzle the world with a wide range of coriolis mass flow meter emerson mass flow meter! Buy one today!! Visit Beijing Sincerity Automatic Equipment Co., Ltd at Sincerity Flow Meter.

Beijing Sincerity Automatic Equipment Co., Ltd offers not only the high-quality product but also the finest service, gives the customer with an expressive using experience.

mass flow meter is sold in oversees market and has high reputation. Besides, our products are sold with reasonable prices.