CN104992735B - Reactor pressure vessel bottom head penetration piece inner wall inspection apparatus - Google Patents

Abstract

The invention discloses a reactor pressure vessel bottom head penetration piece inner wall inspection apparatus. The apparatus comprises a support for fixedly arranging an ultrasound and eddy current combination probe or camera, a second axial driving mechanism for driving the support to move along the axial direction of a penetration piece, a second circumferential driving mechanism for driving the support to move along the circumferential direction of the penetration piece, a second positioning mechanism for realizing positioning of the inner inspection apparatus, and a second buoyancy block arranged at the upper end of the inner wall inspection apparatus. The inner wall inspection apparatus has a compact structure and a small size, can easily and accurately enter the penetration piece under the driving of an operating platform in order to carry out scanning; the apparatus does not generate too large transverse overturning force on the penetration piece due to its small volume weight even if the apparatus shakes; and the buoyancy block offsets the gravity of the inspection apparatus in order to realize stable and easy positioning.

Description

Inner wall inspection device for reactor pressure vessel bottom head penetration

technical field

The invention relates to the field of nuclear power non-destructive testing, in particular to a device for inspecting the inner wall of a penetrating part of a bottom head of a reactor pressure vessel.

Background technique

The nuclear reactor pressure vessel is one of the most important components of a nuclear power plant, and it is an RCC-M nuclear safety first-level equipment. The quality of the nuclear reactor pressure vessel is the key to ensure the safe operation of the nuclear power system, and it is the only large-scale non-replaceable component in the entire life of the nuclear power plant. In order to determine the quality of nuclear reactor pressure vessels, the inspection specifications and outlines of nuclear power plants and nuclear power plants put forward mandatory requirements for non-destructive testing of the welds and other parts of the reactor pressure vessels, and specify that they should be inspected before they are put into use and before they are put into use. Pre-service and in-service inspections of reactor pressure vessels are carried out after a certain time interval of operation. The pre-service and in-service inspection results are an important basis for analyzing and evaluating the operating status of pressure vessels.

The pre-service and in-service inspection of nuclear reactor pressure vessels is a very complicated process, which must be completed with special mechanical inspection equipment and devices. Due to the special structure of the penetrating part of the bottom head of the nuclear reactor pressure vessel, its inspection needs to be carried out in a water environment at a depth of 19 meters, and the inspection process is radioactive. In addition, the inner diameter of the penetration part of the bottom head of the nuclear reactor pressure vessel is only 15.5 mm, but the inspection depth reaches more than 650 mm. The inspection process probe moves inside it, and its positioning requirements are very high. If the inspection device is inaccurately positioned or accidentally disturbed, it is easy to cause the probe to break inside the BMI and cause major hidden dangers to the pressure vessel itself. Published patents CN103985424A (Non-destructive testing robot for nuclear reactor pressure vessel and its testing method), CN203465957U (a nuclear power plant reactor pressure vessel inspection device), CN104464849A (a nuclear power plant reactor pressure vessel inspection device), etc. can perform ultrasonic or video inspection on the entire reactor pressure vessel However, due to the small inner diameter and large depth of the BMI structure, the inspection device cannot complete accurate positioning, and the probe is sent to the inside of the BMI to complete the inspection. At the same time, such equipment or devices are heavy, and any abnormal movement may cause the BMI structure It is subject to a large lateral overturning force, resulting in a huge potential safety hazard.

Published patents 201010576226.8 (ultrasonic automatic inspection device for pressure vessel top cover penetrating pipe fittings), 201010591741.3 (combined structure of TV inspection camera inside pipe fittings), 201010587911.0 (combined structure of ultrasonic inspection probes inside pipe fittings), US patent 20140211902 (INSPECTION APPARATUS FOR PENETRATION PIPEOF NUCLEAR REACTOR ) and other such technologies are mainly aimed at the inspection of reactor pressure vessel top cover penetrations, which cannot meet the installation and operating environment underwater at a depth of 19. In addition, the structure of the top cover penetration is much larger than that of the bottom head penetration, the difficulty of positioning the inspection device is much lower than the inspection requirements of the bottom head penetration, and the probe structure also has enough space for layout.

The inspection technology research reported in the paper (1000MW PWR reactor pressure vessel CRDM and BMI penetration piece J-shaped weld ultrasonic inspection technology research, 2010 China Nuclear Power Industry Science and Technology Innovation and Development Forum Proceedings) mainly focuses on the BMI structure in the manufacturing plant environment The inspection does not involve the radiation environment of the nuclear power plant site, nor can it realize the installation and operation environment at a depth of 19 meters underwater.

Contents of the invention

The object of the present invention is to provide a device for inspecting the inner wall of the penetrating part of the bottom head of the reactor pressure vessel.

In order to solve the above technical problems, the present invention adopts the following technical solutions: a device for inspecting the inner wall of the reactor pressure vessel bottom head penetrating part, which includes a bracket for fixedly installing the ultrasonic and eddy current combined probe or camera, driving the bracket along the A second axial drive mechanism for axially moving the penetrating member, a second circumferential driving mechanism for driving the bracket to move circumferentially along the penetrating member, a second positioning mechanism for positioning the inner wall inspection device, and making the inner wall inspection device in water A second buoyancy block capable of remaining vertical with the brackets below.

Optimally, the range of gravity difference between the second buoyancy block and the inner wall inspection device is [-50, 50]N.

Further, the difference value is 0N.

Optimally, the second upper fixed plate and the second lower fixed plate arranged opposite to each other in the upper and lower positions of the second axial drive mechanism, two symmetrically arranged and connected between the second upper fixed plate and the second lower fixed plate The second guide rail, the disc-shaped second movable platform that is slidably connected to the two second guide rails, the second screw mechanism, and the second screw drive motor, the screw rod of the second screw mechanism passes through the On the second movable platform, the lower end of which is rotatably connected to the second lower fixed plate, the nut of the second screw mechanism is fixed on the second movable platform and sleeved on the second screw mechanism On the screw, the second screw drive motor is fixed on the second upper fixed plate.

Further, the second circumferential driving mechanism passes through the second spline shaft on the second movable platform, drives the second spline shaft to rotate and is installed on the second spline shaft on the second upper fixed plate. The key shaft motor, the second gear that is rotatably connected to the lower end surface of the second movable platform and sleeved on the second spline shaft, is located on the axis of the second movable platform and is rotatably connected to the second The probe connecting rod on the movable platform, and the driven gear fixedly sleeved on the probe connecting rod and meshed with the second gear, the rotation of the second spline shaft drives the rotation of the second gear, and then drives The driven gear rotates, and the driven gear drives the probe connecting rod to rotate, and the bracket is connected to the end of the probe connecting rod to rotate with the probe connecting rod.

Furthermore, the second positioning mechanism includes a cylindrical second positioning seat fixed below the second lower fixing plate, and the inner wall of the second positioning seat is evenly provided with a plurality of second clamping seats at the same height. cylinder and a second positioning block.

The beneficial effect of the present invention is that the inner wall inspection device has a compact structure and a small volume, and can easily and accurately enter the inside of the penetrating part for scanning under the drive of the operating platform. The penetrating piece causes excessive lateral overturning force, and the buoyancy block counteracts the gravity of the inspection device, so that it can stand upright in the water in the pressure vessel and can be positioned more stably and easily.

Description of drawings

Accompanying drawing 1 is the perspective view of inner wall inspection device among the present invention;

Accompanying drawing 2 is the partial view of accompanying drawing 1;

In the drawings: 2. Inner wall inspection device; 3. Long rod assembly; 5. Penetrating piece; 6. Bottom head; 21. Second axial drive mechanism; 22. Second circumferential drive mechanism; 23. Second positioning Mechanism; 24, the second buoyancy block; 211, the second upper fixed plate; 212, the second lower fixed plate; 213, the second guide rail; 214, the second movable platform; 215, the second screw mechanism; 216, the second Two screw rod drive motors; 221, the second spline shaft; 222, the second spline shaft motor; 223, the second gear; 224, the driven gear; 225, the probe connecting rod; 231, the second positioning seat; 232, The second clamping cylinder; 233, the second positioning block.

detailed description

Below in conjunction with the embodiment shown in the accompanying drawings, the present invention is described in detail as follows:

As shown in Figures 1 and 2, the reactor pressure vessel bottom head penetrating piece inner wall inspection device is sent to the penetrating piece 5 by the operation platform and the long rod assembly 3 connected between the operation platform and the inner wall inspection device 2 . It includes a bracket for fixedly installing the ultrasonic and eddy current combined probe or camera, a second axial drive mechanism 21 for driving the bracket to move axially along the penetration 5 , and driving the bracket to move circumferentially along the penetration The second circumferential driving mechanism 22, the second positioning mechanism 23 and the second buoyancy block 24 realize the positioning of the inner wall inspection device.

The second upper fixed plate 211 and the second lower fixed plate 212 of the second axial drive mechanism 21 are arranged oppositely up and down, and are connected between the second upper fixed plate 211 and the second lower fixed plate 212 and are arranged symmetrically. Two second guide rails 213, a disc-shaped second movable platform 214, a second screw mechanism 215, a second screw drive motor 216 that are slidably connected to the two second guide rails 213, the second screw rod The screw rod of the mechanism 215 is passed through the second movable platform 214, and its lower end is rotatably connected to the second lower fixed plate 212, and the nut of the second screw mechanism 215 is fixed on the second movable platform 214 and sleeved on the screw rod of the second screw mechanism 215 , the second screw drive motor 216 is fixed on the second upper fixed plate 211 .

The second circumferential driving mechanism 22 passes through the second spline shaft 221 on the second movable platform 214 , drives the second spline shaft 221 to rotate and is installed on the second upper fixed plate 211 . Two spline shaft motors 222, a second gear 223 rotatably connected to the lower end surface of the second movable platform 214 and sleeved on the second spline shaft 221, located on the axis of the second movable platform 214 and The probe connecting rod 225 rotatably connected to the second movable platform 214, the driven gear 224 fixedly sleeved on the probe connecting rod 225 and meshed with the second gear 223, the second spline The shaft 221 rotates to drive the second gear 223 to rotate, and then drives the driven gear 224 to rotate, and the driven gear 224 drives the probe connecting rod 225 to rotate.

The second positioning mechanism 23 includes a cylindrical second positioning seat 231 fixed below the second lower fixing plate 212, and the inner wall of the second positioning seat 231 is evenly provided with a plurality of second clamping positions at the same height. Cylinder 232 and a second positioning block 233.

The upper end of the inner wall inspection device 2 is provided with a second buoyancy block 24. In this embodiment, the second buoyancy block 24 is covered on the second upper fixed plate 211, and the second buoyancy block 24 and the inner wall inspection The difference range of the gravity of the device 2 is [-50, 50] N, preferably 0 N, because the parts of the inner wall inspection device 2 are evenly distributed, so its center of gravity is roughly on its axis, and the second buoyancy block 24 Located on the upper end of the inner wall inspection device 2 and on the axis, it can effectively maintain the balance of the inner wall inspection device 2 in water, making the positioning operation simpler and more accurate.

The above-mentioned embodiments are only to illustrate the technical concept and characteristics of the present invention, and the purpose is to enable those skilled in the art to understand the content of the present invention and implement it accordingly, and not to limit the protection scope of the present invention. All equivalent changes or modifications made according to the spirit of the present invention shall fall within the protection scope of the present invention.

Claims (5)

1. a kind of RPV bottom head penetration piece inwall check device, it is characterised in that：It is included for fixed peace The support of dress ultrasound and vortex coupling probe or photographic head, the support is driven along the second axially driving of penetration piece axially-movable Mechanism, drive the support along the penetration piece circumferential movement the second circumferential drive mechanism, realize that inwall check device is positioned The second detent mechanism and make inwall check device that vertical state and support underlying second can be kept in water Buoyant mass, on second axial actuating mechanism bottom be oppositely arranged second on fixed disk and the second lower fixed disk, be connected to On second between fixed disk and the second lower fixed disk and symmetrically arranged two second guide rails, be slidably connected to two described The traverser of disc second, the second screw body on two guide rails, the second screw mandrel motor, second screw body Screw rod is arranged in second traverser, and its lower end is rotationally connected with second lower fixed disk, second screw mandrel The nut of mechanism is fixed in second traverser and is set on the screw rod of second screw body, described second Bar motor is fixed on described second on fixed disk.

2. RPV bottom head penetration piece inwall check device according to claim 1, it is characterised in that：Institute It is [- 50,50] N that the second buoyant mass is stated with the difference range of the gravity of the inwall check device.

3. RPV bottom head penetration piece inwall check device according to claim 2, it is characterised in that：Difference Value takes 0N.

4. RPV bottom head penetration piece inwall check device according to claim 1, it is characterised in that：Institute State the second splined shaft, driving the second splined shaft rotation that the second circumferential drive mechanism is arranged in second traverser And be installed on second on fixed disk the second spline spindle motor, be rotationally connected with the second traverser lower surface and cover The second gear that is located on second splined shaft, on the second traverser axis and it is rotationally connected with described second Probe connecting rod, fixed cover in traverser is in the probe connecting rod and driven with what the second gear was meshed Gear, second splined shaft is rotated and drives the second gear to rotate, and then drives driven gear to rotate, driven gear band again Dynamic probe connecting rod is rotated, and support is connected to probe connection boom end and can rotate with probe connecting rod.

5. RPV bottom head penetration piece inwall check device according to claim 1, it is characterised in that：Institute State tubular second positioning seat that the second detent mechanism includes being fixed on below second lower fixed disk, second positioning Seat inwall uniformly has multiple second clamping cylinders and second locating piece on sustained height.