JPS60197B2 - Emergency braking device for reactor vessel inspection equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an emergency braking system for protection and safety in a nuclear reactor vessel inspection system.

The history of nuclear reactor vessel inspection equipment is short, and the reality is that conventional inspection equipment is not equipped with this type of braking device.

Ultrasonic deep damage in PWR (pressurized water type) nuclear reactors uses the water immersion deep damage method from the inside of the reactor vessel, and the deep damage device operates while being inserted into the reactor vessel. The problem here is when the inside surface of the reactor vessel is damaged due to runaway or falling of the manipulator (deep scratch device) during vertical operation, and workers cannot approach it due to radioactive contamination of the reactor vessel itself. , its repair becomes difficult. The present invention is designed to immediately brake and stop the manipulator in the event that the wire rope suspending the manipulator is cut, the manipulator falls due to a failure of the vertical drive transmission system (gears, motors, etc.), or the manipulator runs out of control, resulting in damage to the reactor vessel and the manipulator. This is a safety device to prevent accidents.

Therefore, in the present invention, the detection system is divided into detection systems for when the wire rope loses tension (when it is cut or dropped) and when it runs out of control.In the case of a fall, mechanical braking is applied, and in the case of runaway, the vertical drive motor is stopped until a certain overspeed. When the motor speeds up, the brake attached to the motor is applied, and if the motor speeds up, mechanical braking is applied to reduce damage to the manipulator, and a detection system that can set the overspeed limit steplessly is used. .

Next, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a front view of the reactor vessel ultrasonic deep wound device.

A swing rail 2 is supported by a plurality of support legs 1 on the upper flange surface of the reactor vessel RV.

AP is an alignment pin. A vertical drive device 4 is mounted on the swing rail 2 via a plurality of wheels 3 to support the support legs 1,
It is installed to be able to rotate with respect to the rotation rail 2. A main column 5 is connected to the vertical drive device 4 and hangs down therefrom.

The manipulator 6, which has horizontal, rotational, and bending functions, is held by an isometric body or carriage 7 that can move in a direction perpendicular to the main column 5, and has a number of probes 8 attached to its tip. The carriage 7 is suspended via a sheave 11 from a wire rope 01 that is let out from a hoisting drum 9 built into the vertical drive device 4, and is raised and lowered.
Cutting of wire rope 10 in an ultrasonic deep flaw inspection device in which a probe 8 is moved to an arbitrary position in a reactor vessel RV by vertical movement, rotational movement of a carriage 7, and horizontal, rotational, and bending movements of a manipulator 6. The following will discuss the side of the brake when the manipulator 6 falls or runs out of control due to trouble with the vertical drive motor, transmission gear system, etc. Figure 2 is a front view of the control unit, Figures 3 and 4 are its A
-A, BB cross section is shown.

FIG. 5 shows a CC cross section in FIG. 1. The main column 5 has a cross section as shown in FIG. 5, and a plurality of carriage guide rails 5a, brake rails 6b, and racks (or chains) 5c are attached over substantially the entire length.

Furthermore, the carriage 7 is movable in the vertical direction with respect to the main column 5 by the plurality of rollers 27, and has a structure in which relative rotation is restrained. Further, the sheave I1 is provided on the upper surface of the carriage 7,
Speed detection devices 30 to 41 (details in Fig. 6) to be described later on the side.
is installed. As shown in FIGS. 2 and 3, a placket 12 is fixed to the upper surface of the carriage 7, and a pin 1
It is engaged with the sheave 11 via 3.

Here, since the bracket 12 and pin 13 form a long hole formation, they can be moved up and down by a certain amount. Also, pin 1
A slide shaft 14 is attached to 3 and is also slidable with respect to the bracket 12. The spring 15 is built into the bracket 12 in a direction that constantly pushes down the slide shaft 14. On the other hand, a support 16 is fixed to the carriage 7, and a chopper bar 17 is rotatably connected to the support 16 by a pin. The opposing wedge piece 18, rod bearing 19, and air cylinder 20 are also coupled to the carriage 7.

The slide rod 21 engages with the lever 17 at its upper end, is connected to a piston 22 at its lower end, and receives a downward force from a spring 23. A pair of arms 24 are rotatably connected with pins to the slide rod 21, as shown in FIG.
A roller 25 having a groove on the outer periphery is attached to each arm 24.

Braking rail 5b and the above. The roller 25 normally has a gap c' in the figure. FIG. 6 shows the configuration of the speed detection device.
Pinion (or sprocket) 3 or rack 5
c, and rotates as the carriage 7 moves up and down. 31a, 31b are circular sushi, belt wheel, 32 is a belt,
Reference numeral 33 denotes a belt shifter, which continuously changes the speed of the input rotation of the pinion 30 and transmits it to the bevel gears 34a and 34b. A governor 36 is attached to the lower end of the bevel gear shaft 35 and moves the sleeve 37 up and down in accordance with the rotation speed of the bevel gear shaft 35.

Further, a valve stem 38 is engaged with the sleeve 37 with a gap, and the valve stem 38 is pressed against the valve body 39 by four springs. The proximity switch 41 is installed to detect the raised position of the sleeve 37. During operation, air pressure is constantly applied to the boat W. Boat X is connected to boat Y in FIG. 2, and boat Z in the same figure is open to the atmosphere. The braking device of the present invention having the above-mentioned configuration allows the carriage 7 (and manipulator 6) to quickly move vertically in order to prevent damage due to collision between the reactor vessel and the manipulator 6 when falling or overspeeding occurs during vertical movement. This is an emergency braking device that stops the wire rope 10, and has two built-in systems: one for falling when the wire rope 10 is cut, and one for other falls and overspeed.

First, let's talk about the action when cutting a wire rope.

In FIGS. 2 and 3, the carriage 7 and the manipulator 6 are lifted and lowered by being suspended from a river by a wire rope, but under normal conditions, the weight of the carriage IJ jig 7 and the manipulator 6 is greater than the reaction force of the spring 15. Therefore, the spring 15 is compressed, and the pin 13 is in the down position shown in FIG. 3, in contact with the upper part of the elongated hole of the bracket 12.

When the wire rope 10 breaks, the carriage 7 enters a free fall state and its weight is released, so that the reaction force of the spring 15 instantly pushes the slide shaft 14 downward by an S stroke. Due to this stroke, the lever 17 rotates counterclockwise, and the slide rod 21 is raised (in order to minimize the resistance at this time, the piston 22 has a small hole and the spring 23 has a small spring constant. ) The roller 25 is inserted between the wedge piece 18 and the brake rail 5b to stop the carriage 7 from falling.

Next, we will discuss the effects of falling and overheating other than when the wire rope breaks.

Most vertical drive motors of this type have an electromagnetic brake that operates without excitation.

As the cause of the overspeed of the carriage 7 is also defined as loss of speed control of the motor, in the case of overspeed,
That is, rather than activating the mechanical brake as described above, the motor power is first turned off and the electromagnetic brake is activated to stop the vertical motion. The mechanical braking is activated when braking by the electromagnetic brake is not effective. In FIG. 6, when the carriage 7 moves vertically, the rack 5c, pinion 30, circular ring, belt wheels 31a, 31b, and bevel gear 34a
, 34b, the governor 36 rotates.

When the number of rotations (centrifugal force) increases, the sleeve 37 rises, exceeding the rated value and energizing the proximity switch 41, the power to the vertical drive motor is turned off and the electromagnetic brake is applied. It is sufficient that the carriage 7 stops moving up and down at this stage, but if the rotation increases, the valve stem 38 is raised by the sleeve 37 and the valve is opened. Here, since air pressure is constantly applied to the boat W, the air pressure reaches the Y boat in FIG. 2 from the to stop the carriage 7.

The excitation point of the near twill switch 41 and the opening point of the valve stem 38 can be adjusted by adjusting the positions of the circular belt pulleys 31a, 31b and the belt 32.

The small hole provided in the piston 22 is normally used to release a small leak from the X boat, and since a large amount of air pressure flows in when the valve is open, the leak from this hole can be ignored.

By adopting the emergency braking system of the present invention, damage accidents caused by collisions between the reactor vessel and the manipulator, especially damage to the reactor vessel side, can be prevented, and during inspections during service, operators can be kept at a considerable distance. The device of the present invention can be said to be indispensable because the device is operated remotely from a remote location, so the direct sensation of the device (visual observation, abnormal sounds, etc.) is unknown.

Although the case of an ultrasonic flaw detection device has been described above, the present invention is not limited to this, and it is of course possible to brake various other devices having vertical motion.

[Brief explanation of the drawing]

Figure 1 is a front view of the reactor vessel ultrasonic flaw detection system, Figure 2 is a front view of the control section, Figure 3 is a sectional view taken along line A-A in Figure 2, and Figure 4 is a front view of the reactor vessel ultrasonic flaw detection system.
The figures are a sectional view taken along the line BB in FIG. 2, FIG. 5 is a sectional view taken along the line CC in FIG. 1, and FIG. 6 is a sectional view of the speed detection device. 1...Support leg, 2...Swivel rail, 3...
... Wheels, 4 ... Vertical drive device, 5 ...
... Main pillar, 5a ... Carriage guide rail, 5b ... Braking rail, 5c ... Rack (or chain), 6 ... Manipulator, 7 ... Carriage, 8 ... Search Tentacle, 9...Hoisting drum, 10...
... Wire rope, 11 ... Sheave, 12 ... Bracket, 14 ... Slide shaft, 15 ... Spring, 16 ...
Support, 17... Lever, 18...
Wedge piece, 19...Rod bearing, 20...
air cylinder, 21"" slide rod, 22...piston, 23...spring, 25, 27...roller,
30...Pinion (or sprocket), 31a,
31b...Yen sushi, belt wheel, 32...belt, 33...
... Belt shifter, 34a, 34b ... Bevel gear, 35 ... Bevel gear shaft, 36 ... Governor, 3
7... Sleeve, 38... Benshin, 39
... Valve body, 40 ... Spring, 41
······Proximity switch. Figure 1 Figure 6 Figure 2 Figure 3 Figure 4 Figure 5

Claims (1)

[Claims] 1 An elevating body 7 that has a main pillar 5 arranged vertically and is driven in the vertical direction with a wire rope 10 along this main pillar.
In an emergency braking device for a raw water reactor vessel inspection device used in a fully submerged state, the braking rail 5b is attached to the main pillar, the opposing wedge piece 18 is attached to the elevating body, and the Sheave 11 that suspends the elevating body
A spring 15 is incorporated in the side and has a reaction force in the opposite direction to the weight of the lifting body, and when the weight of the lifting body is no longer applied due to the breakage of the wire rope, the spring 15 moves under the reaction force of the spring and acts as the brake. a drop stop mechanism including a roller 25 inserted between the wedge pieces, a stepless adjustment governor 36 provided on the elevating body and rotated by vertical movement with respect to its main column, and a sleeve raised by this governor. 37; and a proximity switch 41 which is actuated by the proximity of the sleeve to stop the vertical drive motor and actuate an electromagnetic brake attached to the motor; and a proximity switch 41 positioned to engage the still rising sleeve. A nuclear reactor vessel characterized in that it is equipped with a speed-up stop mechanism that operates fluid pressure by a valve opened by a valve stem 38 which is held in place so that the roller 25 is wedged between the braking rail and the wedge piece. Emergency braking device for inspection equipment.