A heat transfer tube inspection probe transmission system

Abstract

The invention discloses a heat transfer tube inspection probe transmission system, including a vacuum generator, the vacuum generator is connected to a filter, the filter is connected to a vacuum interface through a first stop valve, the vacuum interface is connected to a drag reduction chamber, the drag reduction chamber is connected to an airtight ring interface, the airtight ring interface is connected to a stop valve, the stop valve is connected to a third pressure gauge, the third pressure gauge is connected to a second pressure proportional valve, the drag reduction chamber is connected to a probe door, the drag reduction chamber is connected to a pressure interface, the pressure interface is connected to a second stop valve, the second stop valve is connected to a second pressure gauge, the second pressure gauge is connected to a first pressure proportional valve, and the drag reduction chamber is connected to a pusher. The invention has the beneficial effects of: allowing an eddy current probe to pass through a heat transfer tube with less resistance, and the inspection system uses a fluid-driven probe to achieve a resistance reduction function, thereby increasing inspection efficiency, increasing the probe life, and reducing the radiation dose level of operators.

Description

Technical Field

[0001] The invention belongs to the nondestructive detection of heat transfer tubes of steam generators and similar equipment, and in particular relates to a heat transfer tube inspection probe transmission system. Background Art

[0002] Nuclear power plants have a wide variety of heat exchangers and pressure-bearing equipment, which must be non-destructively tested in accordance with certain specifications before and after they are put into operation. Due to the characteristics of the nuclear industry, these equipment are either operated under radioactive conditions or subjected to high temperature and high pressure (tension) and fluctuate frequently, so their inspection cycles are more frequent than those of other industries. At the same time, in order to avoid the consequences of radioactive leakage, their inspection techniques, inspection specifications and other related requirements are also more stringent. The heat transfer tubes of nuclear power plant steam generators are generally inspected using eddy current detection systems. The eddy current detection system is divided into several subsystems according to function. Each functional subsystem has strong independence and can be used separately as needed; it can also be connected to other functional subsystems through a local area network to form a complete detection system, and the communication of each functional subsystem can be realized through the network and software interface. The eddy current detection system is mainly divided into a signal system: collecting eddy current signals and processing signals; a probe positioning system: realizing the positioning of the probe on the collection object; a probe push-pull system: realizing the movement of the probe in the heat transfer tube; an eddy current inspection probe system: realizing the sealing of the probe and the heat transfer tube, and an integrated transmission system: realizing the transmission of various control signals and data between computers and various functional systems. Summary of the invention

[0003] The purpose of the present invention is to provide a heat transfer tube inspection probe transmission system, which enables the eddy current probe to pass through the heat transfer tube with less resistance. The inspection system uses a fluid-driven probe to achieve the function of reducing resistance, thereby increasing the inspection efficiency, increasing the probe life, and reducing the radiation dose level of the operator.

[0004] The technical solution of the present invention is as follows: a heat transfer tube inspection probe transmission system, including a vacuum generator, the vacuum generator is connected to a filter, the filter is connected to a vacuum interface through a first stop valve, the vacuum interface is connected to a drag reduction chamber, the drag reduction chamber is connected to an airtight ring interface, the airtight ring interface is connected to a stop valve, the stop valve is connected to a third pressure gauge, the third pressure gauge is connected to a second pressure proportional valve, the drag reduction chamber is connected to a probe door, the drag reduction chamber is connected to a pressure interface, the pressure interface is connected to a second stop valve, the second stop valve is connected to a second pressure gauge, the second pressure gauge is connected to the first pressure proportional valve, and the drag reduction chamber is connected to a pusher.

[0005] The first pressure proportional valve, the second pressure proportional valve and the vacuum generator are connected to the main inlet of the gas source.

[0006] A first pressure gauge is arranged between the vacuum generator and the filter.

[0007] The probe door includes an upper joint, a cylinder body, a piston, a conduit joint, a descending air port and an ascending air port. The upper end of the cylinder body is connected to the upper joint, the lower end of the cylinder body is connected to the piston, the piston is connected to the conduit joint, and the side end of the cylinder body is connected to the descending air port and the ascending air port.

[0008] The pusher is connected to the lower cover at the bottom of the cylindrical cavity. The cavity has an upper cover. The side wall of the cavity is provided with a vacuum interface, a pressure interface and an airtight ring interface. A recovery guide is arranged inside the cavity, which is airtightly connected to the airtight ring interface. The catheter passes through the upper cover and is connected to the probe door, and the probe is arranged in the catheter.

[0009] The recovery guide comprises a spiral device which is sleeved on the outside of the catheter, and the lower part of the recovery guide is communicated with the vacuum interface.

[0010] The beneficial effect of the present invention is that the present invention is provided with a probe door with lifting action, so that it can be sealed with the tube sheet, ensuring that the pushed and recovered compressed gas will not leak and cause the pressure to drop. The steam generator heat transfer tube inspection device based on fluid drag reduction will increase the probe's passability to the U-shaped heat transfer tube and improve the inspection efficiency. Since the compressed gas is blown into the heat transfer tube, the heat transfer tube can be dried, so the time for drying the heat transfer tube can be reduced before the eddy current inspection. Through the control of the valve, the drag reduction chamber can both assist in pushing the probe and realize the vacuum adsorption probe. The drag reduction chamber can be replaced modularly, and when there is too much dust in the drag reduction chamber, resulting in excessive radiation dose, it can be replaced. The dust filter can effectively collect the radiation dust in the heat transfer tube, thereby effectively reducing the amount of radiation dust in the SAS, and effectively controlling the radiation dose of the operator. Under the vacuum adsorption of the recovery guide, the residual liquid or dust will follow the tube wall and the wire wall, swirl through the recovery guide, flow into the vacuum tube, and be recycled in the form of a filter outside the conduit. This structure is more thorough in recycling. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 A schematic diagram of a heat transfer tube inspection probe transmission system provided by the present invention;

[0012] Figure 2 This is a schematic diagram of the probe door system;

[0013] Figure 3 It is a schematic diagram of the pusher and drag reduction system;

[0014] Figure 4 It is a schematic diagram of the drag reduction cavity structure;

[0015] Figure 5 Schematic diagram of the spiral guide.

[0016] In the figure, 1 is a vacuum generator, 2 is a filter, 3 is a first pressure gauge, 4 is a first stop valve, 5 is a vacuum interface, 6 is a probe door, 7 is a pressure interface, 8 is a second stop valve, 9 is a second pressure gauge, 10 is a pressure proportional valve, 11 is a total air source inlet, 12 is a third stop valve, 13 is a pusher, 14 is an airtight ring interface, 15 is a drag reduction chamber, 17 is a cylinder body, 18 is a piston, 19 is a catheter joint, 20 is a descending air port, 21 is an ascending air port, 22 is an upper cover, 23 is a cavity, 24 is a catheter, 25 is a recovery guide, 26 is an airtight ring, 27 is a cavity, 28 is a lower cover, 29 is a probe, 31 is a third pressure gauge, 32 is a second pressure proportional valve, and 33 is a spiral device. DETAILED DESCRIPTION

[0017] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0018] The heat transfer tube inspection probe transmission system is a steam generator heat transfer tube inspection device based on fluid drag reduction, which is used to assist the eddy current inspection of steam generator heat transfer tubes. Its main function is to reduce the resistance of the eddy current probe when it extends and retracts in the working pipeline, so as to achieve the auxiliary purpose of smooth entry and exit. The fluid drag reduction system is distributed on the positioner, the probe pusher and the probe, including the sealing system, the fluid input system, and the fluid evacuation system, which can realize the remote driving of the probe through the steam generator heat transfer tube. The eddy current probe first pushes the rear flexible cable to the end of the heat transfer tube through the pusher. After the required sealed chamber of the fluid drag reduction system is realized at the end of the tube, compressed air is used to achieve the effect of pressurization or negative pressure to cooperate with driving the eddy current probe in and out of the heat transfer tube. Thereby improving the inspection efficiency.

[0019] The probe positioning system mainly involves the probe door with lifting action, so that it can be sealed with the tube sheet. The control system needs to increase the control of the probe door, and the software system needs to increase the control interface of the probe door. Automatic positioning requires the action logic of the probe door to be integrated into the original positioning logic. The top of the probe door is sealed with the working pipeline. The entire system fixes the telescopic device on the walking mechanism through a bracket. The movement of the walking mechanism performs the positioning of the pipeline being operated. After it is in place, the telescopic head extends and docks with the working pipeline to form a sealing surface.

[0020] The function of the probe driving pusher is to send the probe from the bottom of the water chamber tube sheet into the heat transfer tube to the other end of the water chamber, and then collect the eddy current data of the heat transfer tube when pulling back. The upper end of the drag reduction cavity of the probe pusher system is tightly sealed with the probe door through the upper cover, and the entire probe runs through it, and is sealed at the lower end through the airtight ring, and the lower end is connected to the puller. The cavity is divided into five parts: upper cover, cavity, recovery guide, airtight ring and lower cover. There are pressure port, vacuum port and airtight port on the cavity, three interfaces, which are connected to positive pressure, vacuum device, and airtight pressure respectively. When the probe needs to enter the working pipe, the front valve of the vacuum tube is closed, and the pusher is in the "pushing" state. When the probe needs to be withdrawn, the front valve of the pressure tube is closed, and the front valve of the vacuum tube is opened to evacuate the entire pressure chamber. The pressure generated by the pressure difference of the probe head section is used to "suck" the probe back, and the pusher is in the "pulling" state.

[0021] When the probe is "back-sucking", residual liquid or dust may flow back, and the recovery guide starts to work. The lower outlet of the recovery guide is connected to the vacuum port. Under the adsorption of the vacuum, the residual liquid or dust will follow the tube wall and the wire wall, swirl through the recovery guide, flow into the vacuum tube, and be recovered in the form of a filter outside the catheter.

[0022] like Figure 1-5 As shown, a heat transfer tube inspection probe transmission system includes a vacuum generator 1, a filter 2, a first pressure gauge 3, a first stop valve 4, a vacuum interface 5, a probe door 6, a pressure interface 7, a second stop valve 8, a second pressure gauge 9, a pressure proportional valve 10, a gas source main inlet 11, a third stop valve 12, a pusher 13, an airtight ring interface 14 and a drag reduction chamber 15, wherein the vacuum generator 1 is connected to the filter 2, a first pressure gauge 3 is arranged between the vacuum generator 1 and the filter 2, the filter 2 is connected to the vacuum interface 5 through the first stop valve 4, and the vacuum interface 5 is communicated with the drag reduction chamber 15, The drag reduction chamber 15 is communicated with the airtight ring interface 14, the airtight ring interface 14 is connected to the stop valve 12, the stop valve 12 is connected to the third pressure gauge 31, the third pressure gauge 31 is connected to the second pressure proportional valve 32, the drag reduction chamber 15 is connected to the probe door 6, the drag reduction chamber 15 is communicated with the pressure interface 7, the pressure interface 7 is connected to the second stop valve 8, the second stop valve 8 is connected to the second pressure gauge 9, the second pressure gauge 9 is connected to the first pressure proportional valve 10, the drag reduction chamber 15 is connected to the pusher 13, the first pressure proportional valve 10, the second pressure proportional valve 32 and the vacuum generator 1 are connected to the total gas source inlet 11.

[0023] like Figure 2As shown, the probe door 6 includes an upper joint 16, a cylinder body 17, a piston 18, a duct joint 19, a descending air port 20 and an ascending air port 21. The upper end of the cylinder body 17 is connected to the upper joint 16, the lower end of the cylinder body 17 is connected to the piston 18, the piston 18 is connected to the duct joint 19, and the side end of the cylinder body 17 is connected with the descending air port 20 and the ascending air port 21.

[0024] like Figure 3 and Figure 4 As shown, the pusher 13 is connected to the lower cover 28 at the bottom of the cylindrical cavity 23, the cavity 23 has an upper cover 22, the side wall of the cavity 23 is provided with a vacuum interface 5, a pressure interface 7 and an airtight ring interface 14, a recovery guide 25 is arranged inside the cavity 23, the airtight 26 is connected to the airtight ring interface 14, the conduit 24 passes through the upper cover 22 and is connected to the probe door 6, and the probe 29 is arranged in the conduit 24.

[0025] like Figure 5 As shown, the recovery guide 25 includes a spiral device 33 which is sleeved on the outside of the catheter 24 , and the lower part of the recovery guide 25 is communicated with the vacuum interface 5 .

[0026] like Figure 1 As shown, the heat transfer tube inspection probe transmission system provided by the present invention belongs to the auxiliary system part of the steam generator heat transfer tube inspection system. The probe door is fixed on the positioner through a bracket. The positioner uses robot path planning according to the arrangement of the heat transfer tubes on the tube sheet and the tube spacing, moves the probe door of the positioner, accurately positions the eddy current probe just below the tube mouth of the heat transfer tube to be inspected, controls the guide tube of the probe door to extend, and docks with the heat transfer tube to be operated to form a sealing surface, so that the top of the guide tube can be sealed with the tube sheet.

[0027] Then, the eddy current probe is sent into the drag reduction cavity through the pusher. The upper end of the drag reduction cavity and the probe door are tightly sealed through the upper cover. The entire probe runs through it, and is sealed at the lower end through the airtight ring, and the lower end is connected to the pusher. When the probe needs to enter the bellows, the valve at the front end of the vacuum tube is closed, the pusher is in the "pushing" state, the valve at the front end of the pressure tube is opened, the cavity is filled with gas, and the airtight ring is filled with the same pressure as the cavity. The airtight ring is in a normal seal, and at the end of the probe stroke pressure difference, the probe can be pushed in the heat transfer tube with reduced resistance. When the probe needs to be withdrawn, the valve at the front end of the pressure tube is closed, and the valve at the front end of the vacuum tube is opened to evacuate the entire pressure cavity. The pressure generated by the pressure difference in the cross section of the probe head is used to "suck" the probe back, while the pusher is in the "pulling" state. When the probe "re-absorbs", residual liquid or dust may flow back, and the recovery guide starts to work. The outlet at the lower end of the recovery guide is connected to the vacuum port. Under vacuum adsorption, the residual liquid or dust will flow along the pipe wall and the wire wall, swirl through the recovery guide, flow into the vacuum tube, and be recovered in the form of a filter outside the tube to collect radiation pollutants. The positioner moves to the next heat transfer tube hole to be inspected according to the inspection plan, and operates in this reciprocating cycle until the inspection is completed.

Claims

1. A heat transfer tube inspection probe transmission system, characterized in that: It includes a vacuum generator, the vacuum generator is connected to the filter, the filter is connected to the vacuum interface through the first stop valve, the vacuum interface is connected to the drag reduction chamber, the drag reduction chamber is connected to the airtight ring interface, the airtight ring interface is connected to the stop valve, the stop valve is connected to the third pressure gauge, the third pressure gauge is connected to the second pressure proportional valve, the drag reduction chamber is connected to the probe door, the drag reduction chamber is connected to the pressure interface, the pressure interface is connected to the second stop valve, the second stop valve is connected to the second pressure gauge, the second pressure gauge is connected to the first pressure proportional valve, and the drag reduction chamber is connected to the pusher; The first pressure proportional valve, the second pressure proportional valve and the vacuum generator are connected to the main inlet of the gas source; A first pressure gauge is provided between the vacuum generator and the filter; The probe door comprises an upper joint, a cylinder body, a piston, a conduit joint, a descending air port and an ascending air port, the upper end of the cylinder body is connected to the upper joint, the lower end of the cylinder body is connected to the piston, the piston is connected to the conduit joint, and the side end of the cylinder body is connected to the descending air port and the ascending air port; The pusher is connected to the lower cover at the bottom of the cylindrical cavity, the cavity has an upper cover, the side wall of the cavity is provided with a vacuum interface, a pressure interface and an airtight ring interface, a recovery guide is arranged inside the cavity, the airtight is connected to the airtight ring interface, the catheter passes through the upper cover and is connected to the probe door, and the probe is arranged in the catheter; The recovery guide comprises a spiral device which is sleeved on the outside of the catheter, and the lower part of the recovery guide is communicated with the vacuum interface.

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