JPH1020060A - Nuclear fuel rod length measuring device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To measure the length of a nuclear fuel rod at a higher speed with a higher precision by reading the shape data such as upper and lower end plugs from the marking of a nuclear fuel rod to determine the moving quantity of a contact type sensor. SOLUTION: A nuclear fuel rod 10 to measure the length is placed and fixed onto a surface plate 23 after the marking data on the lower end plug is read by an end plug marking reader 41. Cylindrical auxiliary measuring jigs 32, 34 having contact type sensors 31, 33 mounted thereon are moved at high speed along driving shafts 28, 27 by the moving quantity determined by a data processing device 43 by use of the marking data, and brought into contact with the end part of the fuel rod 10, and the length of the fuel rod 10 is thus quickly measured from this position. The measurement data is compared with a reference length in a processing device 43. Since the jigs 32, 34 made of soft synthetic resin have stepped part or diameter extended part so as to be precisely contactable with the fuel rod end part, and are formed so as to be suitable to any fuel rod, a highly precise and highly efficient measurement can be performed, and the fuel rod is never damaged in measurement.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a nuclear fuel rod length measuring device, and more particularly to a nuclear fuel rod length measuring device using a contact type sensor.

[0002]

2. Description of the Related Art Generally, nuclear fuel rods include a standard nuclear fuel rod 10 shown in FIG. 8, a corner nuclear fuel rod 11 shown in FIG. 9, and a combined nuclear fuel rod 12 shown in FIG. Each of these nuclear fuel rods 10 and the like has upper and lower end plugs B1, B2, B3 and lower end plugs C1,
C2 and C3 are attached.

[0003] The lower end plug C of these standard nuclear fuel rods 10 etc.
The number 1 is usually engraved with the number of the nuclear fuel rod, and the type of the nuclear fuel rod, the shape of the upper and lower end plugs B1, B2, etc., and the shapes of C1, C2, etc. are identified.

[0004] The length of these nuclear fuel rods is usually inspected at the stage of completion of assembling, and the production accuracy, the assembling accuracy and the like are confirmed.

[0005] This inspection includes a method in which an operator directly measures, and a method using a measuring device using image processing, a non-contact sensor, a contact sensor, or the like.

Although the method of measuring the length of a nuclear fuel rod directly by an operator using a gauge or the like is simple, there is a problem that the measurement is performed manually, which takes a long time and causes a measurement error. .

[0007] The measurement method by image processing is capable of measuring the length of a nuclear fuel rod by processing an image captured by a television camera, so that high-precision measurement is possible. There is a problem that the cost is required and the installation place is enlarged.

[0008] The measurement method using a non-contact type sensor is excellent in that it does not damage the surface of the nuclear fuel rod, but has a problem that the measurement time is long.

Further, the measurement method using a contact type sensor can reduce the cost of ancillary equipment and reduce the installation space. However, since the shape of the nuclear fuel rod is not recognized, the sensor cannot be brought into contact with the upper and lower end plugs at high speed and the measurement can be performed. There was a problem that it took time.

[0010]

Although all of these measuring methods have advantages and disadvantages, the present invention is an improvement of a measuring method using a contact type sensor which requires a small amount of incidental equipment and requires only a small installation space. .

In the measurement method using the contact type sensor, the contact type sensor is moved from both ends thereof until it comes into contact with the ends of the upper and lower end plugs, regardless of the difference in the shape of the upper and lower end plugs of the nuclear fuel rod, and the contact point is moved between the contact points. The length of the nuclear fuel rod is measured by the length of the nuclear fuel rod.

For this reason, it is necessary to reduce the impact by reducing the moving speed of the contact type sensor.

Further, when the moving contact type sensor breaks down, there is a danger that it will not stop and give a strong impact to the nuclear fuel rod.

Further, in this contact type sensor, each time a different nuclear fuel rod, such as a standard nuclear fuel rod, a corner nuclear fuel rod, or a combined nuclear fuel rod, is measured, the upper and lower ends of the upper and lower ends are changed due to the difference in the shape of the upper and lower end plugs. A measuring auxiliary jig suitable for the stopper had to be attached.

Therefore, there is a problem that the length of the nuclear fuel rod cannot be measured at high speed.

In view of the above, the present invention provides a nuclear fuel rod length measuring device which can measure at high speed without damaging the surface of the nuclear fuel rod irrespective of the difference in the shape of the end plug. The purpose is to obtain.

[0017]

According to the present invention, a sensor is moved from both ends of a nuclear fuel rod fixed to a surface plate, and the sensor is moved from a position where the sensor contacts upper and lower end plugs at the end of the nuclear fuel rod. In a nuclear fuel rod length measuring device for measuring the length of a fuel rod, a shape data detecting means for detecting shape data of the nuclear fuel rod, and a movement amount of the sensor from the shape data detected by the shape data detecting means. A moving amount determining means for determining, and a driving means for driving the sensor toward upper and lower end plugs of the end of the nuclear fuel rod by the moving amount determining means are provided.

Further, the sensor according to the present invention is characterized in that a cylindrical auxiliary measuring jig which surrounds the upper and lower end plugs and comes into contact with the upper and lower end plugs at the end of the nuclear fuel rod is attached.

Further, the present invention is characterized in that the cylindrical auxiliary measuring jig is made of a flexible synthetic resin.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the nuclear fuel rod length measuring apparatus of the present invention will be described below with reference to the accompanying drawings.

The nuclear fuel rod length measuring device 20 of the present invention is provided with a measuring table 22 mounted on a foundation 21.
A platen 23 is disposed above the measuring table 22, and a nuclear fuel rod such as the standard nuclear fuel rod 10 is mounted on the platen 23.

A plurality of dial gauges 24a, 24b, 24c and the like are arranged at predetermined intervals on the surface plate 23 so as to measure and correct the bending of the nuclear fuel rods 10 and the like.

On both sides of the platen 23, parallel drive shafts 27 and 28 driven by a first servomotor 25 and a second servomotor 26 are provided.

The drive shaft 27 is provided with a male screw 27a at a portion close to the first servomotor 25 so that the first servomotor 2
The drive shaft 28 is formed of a normal shaft having no screw at a portion remote from the second servomotor 26. Similarly to the drive shaft 27, a male screw 28a is cut at a portion close to the second servomotor 26. It consists of a normal shaft without screws.

The drive shafts 27 and 28 have a female threaded block 29a and a block 29b having only a through hole.
1st connection block 2 which connected with the support arm 29c
9 and a second connecting block 30 in which a block 30a in which only a through hole is formed and a block 29b with a female thread are connected by a supporting arm 30c, respectively, and are driven by the first servomotor 25 and the second servomotor 26. The first connection block 29 and the second connection block 30 are connected to the drive shaft 2
It moves in the left-right direction along 7,28.

A first cylindrical auxiliary measuring jig 32 to which a first contact type sensor 31 is attached is provided above the support arm 29c, and a second contact type sensor 3 is provided above the support arm 30c.
3 is provided with a second cylindrical auxiliary measuring jig 34,
The first cylindrical auxiliary measuring jig 32 is brought into contact with the upper end plug B1 and the second cylindrical auxiliary measuring jig 34 is brought into contact with the lower lower end plug C1 and the like.

A plurality of fixing jigs 35 are provided above the measuring table 22.
A support base 36 for supporting a, 35b, 35c, etc. is provided, and the nuclear fuel rods 10 and the like on the surface plate 23 are fixedly supported by the fixing jigs 35a, 35b, etc.

The first cylindrical auxiliary measuring jig 32 is made of a synthetic resin cylinder, and has a large-diameter portion 3 having an inner diameter slightly larger than the outer diameter of the fuel rod portion A at its tip as shown in FIG.
2a is formed, and a small inner diameter portion 32b is formed at the base end through which an upper end plug B1 or the like slightly smaller than the outer diameter of the fuel rod portion A can be inserted, and between the large diameter portion 32a and the small inner diameter portion 32b. A step 32c is formed at the left end of the base, and the first contact sensor 31 is attached to the left end of the base end.

When the length of the nuclear fuel rod 10 or the like is measured by the first contact type sensor 31, the first cylindrical auxiliary measuring jig 32 is connected to the fuel rod such as the nuclear fuel rod 10 via the upper end plug B1 or the like. The step 32 is inserted so as to surround the portion A.
c comes into contact with an end Be of an upper end plug B1 or the like of the nuclear fuel rod 10 or the like.

The first cylindrical auxiliary measuring jig 34 is made of a synthetic resin cylinder like the first cylindrical auxiliary measuring jig 32, and can be inserted with a lower end plug C1 or the like as shown in FIG. A small-diameter portion 34a and an enlarged-diameter portion 34b whose inner diameter is enlarged at the distal end thereof are formed, and the second contact sensor 33 is attached to the right end of the small-diameter portion 34a.

When the length of the nuclear fuel rod 10 and the like is measured by the second contact type sensor 33, the second cylindrical auxiliary measuring jig 34 is inserted into the lower end plug C1 and the like, and the enlarged diameter portion 34b
Is in contact with the inclined portion such as the lower end plug C1 of the end Ce of the nuclear fuel rod 10 or the like.

Further, a nuclear fuel rod end plug marking reading device 40 is provided near the nuclear fuel rod length measuring device 20. The nuclear fuel rod end plug engraving reading device 40 is provided with an end plug engraving reading table 42 having an end plug engraving reader 41,
The end plug marking reader 41 reads the marking on the lower end C1 and the like of the nuclear fuel rod, and sends the shape data of the upper and lower end plugs B1 and C1 to the data processor 43.

A case where the length of the standard nuclear fuel rod 10 is measured using the nuclear fuel rod length measuring device 20 having such a configuration will be described.

The standard nuclear fuel rod 10 whose length is to be measured is placed on the end plug marking reading stand 42, and the marking on the lower end plug C 1 of the standard nuclear fuel rod 10 is read by the end plug marking reader 41. The read engraved data is sent to the data processing device 43.

The data processor 43 calculates the shape data of the upper end plug B1 and the lower end plug C1 of the standard nuclear fuel rod 10 from the engraved data, and from the calculated data, the first servomotor 2
5. Determine the drive amount of the second servomotor 26. The drive amount data is sent to the upper servo motors 25 and 26.

Standard nuclear fuel rod 1 from which the engraved data was read
0 on the platen 23 and fixing jigs 35a, 35
The standard nuclear fuel rod 10 is fixed to the surface plate 23 by b or the like.

When this fixing is performed, the dial gauge 24a
, 24b, etc., detects the bending of the standard nuclear fuel rod 10 and corrects it so that no bending occurs.

When such a preliminary operation is completed, the first servomotor 25 and the second servomotor 26 are driven to drive the drive shaft 2
7, 28 are rotated.

The rotation of the drive shaft 27 causes the block 29 to rotate.
a is moved in the direction of the arrow along the male screw 27a, and the block 29b associated therewith is moved at high speed along the drive shaft 28 by the amount of movement in the direction of the arrow.

The rotation of the drive shaft 28 causes the block 30b to move in the direction of the arrow along the male screw 30b, and the block 30a associated therewith to move along the drive shaft 27 at a high speed in the direction of the arrow by the amount of movement.

By this movement, the first cylindrical auxiliary measuring jig 3
2. The second cylindrical auxiliary measuring jig 34 is brought into contact with the end Be via the upper end plug B1 and the end Ce via the lower end plug C1,
The length of the nuclear fuel rod 10 is quickly measured by the first contact type sensor 33 and the second contact type sensor 33 from the movement amounts of the first cylindrical auxiliary measuring jig 32 and the second cylindrical auxiliary measuring jig 34. .

The measured data is sent to the data processor 43 and compared with the reference length data of the standard nuclear fuel rod 10. If the comparison values match, the inspection standard nuclear fuel rod 10 is treated as a passing product.

In the measurement of the length of the nuclear fuel rod, the first
Even if the contact-type sensor 31 and the second contact-type sensor 33 fail, the first connection block 29 and the second connection block 30 need only be moved by the lengths of the upper end plug B1 and the lower end plug C1. The first cylindrical auxiliary measuring jig 32, the second
The cylindrical auxiliary measurement jig 34 is not brought into contact with the nuclear fuel rod 10 by giving an impact.

The first cylindrical auxiliary measuring jig 32 attached to the first contact type sensor 31 is provided with a step 32c, and the second cylindrical auxiliary measuring jig attached to the second contact type sensor 33. Since the diameter-enlarged portions 34b are provided at 34, they can be brought into accurate contact with the ends of the nuclear fuel rods, and the length of the nuclear fuel rods 10 can be measured accurately.

Further, the first cylindrical auxiliary measuring jig 32, the second
The cylindrical auxiliary measuring jig 34 is shaped to fit the upper and lower end plugs of any nuclear fuel rods, etc., so that it is possible to relieve the trouble of replacing and measuring each time even when measuring different nuclear fuel rods, and to improve the efficiency of measurement. Can be achieved.

Further, the first cylindrical auxiliary measuring jig 32 and the second
Since the cylindrical auxiliary measuring jigs 34 are made of a soft synthetic resin, they do not damage the nuclear fuel rods even if they come into contact.

The measurement of such a nuclear fuel rod can be performed in the same manner when measuring another nuclear fuel rod, for example, a corner nuclear fuel rod 11, a combined nuclear fuel rod 12, and the like.

[0048]

According to the present invention, the sensor is moved from the left and right directions of the nuclear fuel rod fixed to the surface plate, and the sensor is moved from the position where the sensor comes into contact with the upper and lower end plugs at the end of the nuclear fuel rod. In a nuclear fuel rod length measuring device for measuring the height, a shape data detecting means for detecting shape data of the nuclear fuel rod, and a moving amount determining means for determining a moving amount of the sensor from the shape data detected by the shape data detecting means. Means and driving means for driving the sensor toward the upper and lower end plugs of the end of the nuclear fuel rod by means of this moving amount determining means. Not only can be measured, but also the sensor can accurately contact the upper and lower end plugs of the end of the nuclear fuel rod to perform highly accurate measurement.

Further, the sensor of the present invention is provided with a cylindrical auxiliary measuring jig which surrounds the upper and lower end plugs and comes into contact with the upper and lower end plugs at the ends of the nuclear fuel rods. Can be used as it is, and the measurement efficiency can be increased.

Further, since the cylindrical auxiliary measuring jig of the present invention is made of a flexible synthetic resin, it does not damage the nuclear fuel rod during the measurement.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing an outline of a nuclear fuel rod length measuring device of the present invention.

FIG. 2 is a plan view showing a part of FIG.

FIG. 3 is an enlarged side view showing a main part of FIG. 1;

FIG. 4 is an enlarged plan view showing a main part of FIG. 2;

FIG. 5 is an enlarged sectional view showing a first cylindrical auxiliary measuring jig of FIG. 1;

FIG. 6 is an enlarged sectional view showing a second cylindrical auxiliary measuring jig of FIG. 1;

FIG. 7 is a plan view of an end plug engraving reading table.

FIG. 8 is a plan view of a commonly used standard nuclear fuel rod.

FIG. 9 is a plan view of a commonly used corner nuclear fuel rod.

FIG. 10 is a plan view of a commonly used bonded nuclear fuel rod.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Standard nuclear fuel rod 11 Corner nuclear fuel rod 12 Combined nuclear fuel rod 20 Nuclear fuel rod length measuring device 21 Basic 22 Measurement table 23 Surface plate 24a, 24b ... Dial gauge 25, 26 Servo motor 27, 28 Rotation axis 29, 30 Connecting block 31, 33 Contact type sensor 32, 34 Cylindrical auxiliary measuring jig 35a, 35b, 35c ... Fixing jig 40 Nuclear fuel rod end plug engraving reading device 41 End plug engraving reader 42 End plug engraving reading stand 43 Data processing apparatus

Claims (3)

[Claims] A sensor is moved from the left and right direction of a nuclear fuel rod fixed to a surface plate, and the sensor measures the length of the nuclear fuel rod from a position where the sensor contacts upper and lower end plugs at the end of the nuclear fuel rod. A nuclear fuel rod length measuring device, wherein: a shape data detecting means for detecting shape data of the nuclear fuel rod; a moving amount determining means for determining a moving amount of the sensor from the shape data detected by the shape data detecting means; And a driving means for driving the sensor toward upper and lower end plugs at the end of the nuclear fuel rod by the moving amount determining means. 2. The sensor according to claim 1, further comprising a cylindrical auxiliary measuring jig surrounding the upper and lower end plugs and contacting the upper and lower end plugs at the ends of the nuclear fuel rods. Nuclear fuel rod length measuring device. 3. The nuclear fuel rod length measuring device according to claim 1, wherein the cylindrical auxiliary measuring jig is made of a flexible synthetic resin.