CN104005946A - Reactor coolant pump flow speed controller - Google Patents

Abstract

The invention relates to a reactor coolant pump flow speed controller which is placed at a reactor coolant pump low-pressure leakage system and is used for monitoring low-pressure leakage flow of three-level fluid dynamic pressure mechanical sealing. The reactor coolant pump flow speed controller is one of the most important auxiliary devices of a reactor coolant pump. Important study-judge data are provide for analyzing whether the reactor coolant pump is in a normal working state. The principle of a volumetric flowmeter is used for designing a flow measuring device special for a reactor coolant pump low-pressure leakage system, and the controller has the advantages of being simple in structure, accurate in measured data and reliable in operation.

Description

Reactor Coolant Pump Flow Controller

TECHNICAL FIELD: This invention relates to reactor coolant pump flow rate controllers.

Background technology: The reactor coolant pump flow rate controller is one of the important measurement and control equipment in the auxiliary system of the reactor coolant pump. It is used to monitor whether the three-stage hydrodynamic mechanical seal of the reactor coolant pump is working normally. It can directly judge whether the reactor coolant pump of the nuclear power plant is in a safe and reliable operation state. At present, there is no similar product for reactor coolant pumps in China.

Invention content:

The object of the present invention is to disclose a reactor coolant pump flow rate controller with high reliability, low maintenance cost and convenient overall disassembly and assembly. The technical scheme of the present invention is: a reactor coolant pump flow rate controller, a flange is respectively installed on the left side of the main valve body and the bottom of the main valve body, and the left flange (18) is connected with the inlet pipe and has a hexagonal nut The inlet pipe (11) of (12) is threadedly connected with the casing (1), the sealing ring (13) is installed in the sealing groove of the casing (1), and the liquid level switch (15) is installed vertically on the cover (17). The sealing ring (16) is used to seal between them, the probe (21) of the liquid level switch (15) is located in the measuring container (10), and the measuring container (10) is located in the valve chamber (22); the bottom flange (14) With an outlet pipe (23), the outlet pipe (23) communicates with the measuring container (10), and the seal between the cover (17) and the housing (1) is sealed by a wound gasket (2) and through the waist bolt (3) and The hexagonal nut (4) is fixed, and the shell (1) has a cylindrical pin (5), which is used for positioning when the cover (17) is installed, between the bottom flange (14) and the shell (1) Rely on wound gasket (6) and connect through hex nut (9), sleeve (8) and waist bolt (7).

The working principle of the present invention:

The flow rate controller is located on the reactor coolant pump low-pressure leakage system and is used to monitor the low-pressure leakage flow of the three-stage hydrodynamic mechanical seal.

When the low-pressure leakage flow rate is higher than the design value, it indicates that the three-stage hydrodynamic mechanical seal is damaged, and the reactor coolant pump is not allowed to continue to run at this time.

The inlet and outlet flanges (14) of the flow rate controller are welded to the low-pressure leakage system pipeline. The low-pressure leakage enters the flow rate controller in the direction indicated by the arrow in the figure, and flows into the measuring container (10) through the inlet pipe (11). The inner measuring container ( The volume of 10) and the size of the water outlet hole are determined by calculation. When the flow rate is less than the design value, the liquid flow can flow out through the water outlet hole on the measuring container (10), and flow out of the flow rate controller in the direction indicated by the arrow in the figure. The liquid level will not rise to the switch liquid level; when the flow rate is greater than the design value, the liquid flow cannot be completely discharged through the outlet hole. At this time, the liquid level in the measuring container (10) will continue to rise. When reaching the switch liquid level, the liquid level switch (15) will send a signal, prompting that the low pressure leakage flow is too large.

The beneficial effects of the present invention are:

The invention is a measuring device specially used for measuring the low-pressure leakage flow rate of the three-stage fluid dynamic pressure mechanical seal of the reactor coolant pump, which fills the blank of such products in China. The invention relies on the inlet pipe and the measuring container to form a liquid flow channel for low-pressure leakage in the inner cavity of the flow rate controller. The volume of the measuring container and the flow rate of the water outlet hole have been calibrated. The hole flows out; when the flow rate is greater than the design value, the liquid cannot be completely discharged through the outlet hole, and the liquid level in the measuring container will rise. When it rises to the switch liquid level, the liquid level switch will send a signal to the control room through the probe . The successful development of the flow rate controller will make a big step forward in the localization of my country's nuclear main pumps, provide a strong guarantee for the safety of nuclear power plants, and prepare for the country's nuclear power to compete in the international market and export to third parties. . The reactor coolant pump flow rate controller of the invention has high reliability, is easy to disassemble and assemble, has low maintenance cost, is beneficial to the maintenance of the nuclear main pump, and has a wide application range.

Description of drawings

Figure 1 is a cross-sectional view of the reactor coolant pump flow rate controller

Fig. 2 is the sectional view of measuring container (10)

Detailed ways

As shown in Figure 1, a reactor coolant pump flow rate controller, a flange is installed on the left side of the main valve body and the bottom of the main valve body, the left flange 18 communicates with the inlet pipe, and the inlet with hex nut 12 The pipe 11 is screwed to the casing 1, the sealing ring 13 is installed in the sealing groove of the casing 1, the liquid level switch 15 is installed vertically on the cover 17, and the sealing ring 16 is used to seal the two, and the probe 21 of the liquid level switch 15 Located in the measuring container 10, the measuring container 10 is located in the valve chamber 22; the bottom flange 14 has an outlet pipe 23, the outlet pipe 23 communicates with the measuring container 10, and the wound gasket 2 is used to seal between the cover 17 and the housing 1 and through The waist bolt 3 and the hexagon nut 4 are fixed, and the shell 1 is equipped with a cylindrical pin 5, which is used for positioning when the cover 17 is installed, and the bottom flange 14 and the shell 1 are sealed by the wound gasket 6 and passed through the hexagonal pin. Nut 9, sleeve 8 and waist bolt 7 are connected.

As shown in FIG. 2 , the structure of the measuring container 10 is as follows: the side wall of the container has a water outlet hole 19 with flow calibration, the inner chamber 24 of the container has a volume calibration, and the bottom of the container has a drainage groove 25 .

The invention guarantees the accuracy of the measurement result by calibrating the measuring container and the water outlet hole, has a reliable structure, and has low operation and maintenance costs.

Claims (2)

1. A reactor coolant pump flow rate controller is characterized in that: a flange is respectively installed on the left side of the main valve body and the bottom of the main valve body, and the left side flange (18) is communicated with the inlet pipe, with a hexagonal nut ( The inlet pipe (11) of 12) is threadedly connected with the housing (1), the sealing ring (13) is installed in the sealing groove of the housing (1), and the liquid level switch (15) is installed vertically on the cover (17). The sealing ring (16) is used to seal between them, the probe (21) of the liquid level switch (15) is located in the measuring container (10), and the measuring container (10) is located in the valve chamber (22); the bottom flange (14) has There is an outlet pipe (23), the outlet pipe (23) communicates with the measuring container (10), the seal between the cover (17) and the housing (1) is sealed by a wound gasket (2) and the waist bolt (3) and the hexagon The nut (4) is fixed, and the shell (1) has a cylindrical pin (5), which is used for positioning when the cover (17) is installed, and the bottom flange (14) and the shell (1) rely on The wound gasket (6) is sealed and connected by a hex nut (9), a sleeve (8) and a waisted bolt (7). 2. A kind of reactor coolant pump flow rate controller according to claim 1, characterized in that: the structure of the measuring container (10) is: the container side wall has a water outlet hole (19) through flow calibration, The inner cavity (24) of the container has a volume calibration, and a drainage groove (25) is arranged at the bottom of the container.