RU1259869C - Drive of nuclear reactor final control element - Google Patents

Description

The invention relates to nuclear engineering and can be used as a drive for a regulatory body of a nuclear reactor.

The purpose of the invention is to simplify manufacturing and installation work.

Fig. T shows a drive of a regulatory body of a nuclear reactor, a longitudinal section; 2 shows section AA in FIG. 1.

The drive of the regulatory body of the nuclear reactor contains a tight-fitting cover 1 made of, for example, non-magnetic steel {see. 1), there is a flange 2 with which the sheath 1 is fastened and sealed with its lower part on a nuclear reactor (not shown).

In the upper part, the cover 1 is sealed by means of squeezing bolts 3 with a plug 4 with a conical gasket 5. In addition, the specified drive has a position sensor 6 mounted on the plug 4, located inside the cover 1, the movement mechanism 7 n located outside the cover 1, a removable block of electromagnets 8, which consists of electromagnets 9,10, 11, rigidly connected by posts 12, 13, support 14 and the upper strut 15. In addition, the block of electromagnets 8 includes a band 16, consisting of a sleeve 17 and a ring 18 having at least one length 1 section 19 (see Fig. 2). The maximum outer diameter of the position sensor 6 is chosen smaller than the minimum inner diameter D, the block of electromagnets 8. The sleeve 17 has an inner conical surface 20, the minimum inner diameter of which D „„ 6 ”, the ring 18 has an outer conical surface 21, conjugated with an inner conical surface 20 , and the inner cylindrical surface 22. The cover has, in the location of the conical strip 5, an outer cylindrical surface 23 having a diameter D, mating with the inner cylindrical surface Stu 22, and holds sootnotonie

 D, D. Dpp (O.

 5 D. (2)

The ring 18 with its lower end abuts against the upper rack 15 of the block of electromagnets 8. The sleeve 16 secures

10

fifteen

twenty

25

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with to the upper strut 15 studs 24 with nuts 25.

The movement mechanism 7 comprises movable poles 26, 27, 28, 29 connected to latches 30, 31, a rod

32 associated with the regulatory authority of a nuclear reactor (not shown).

To install the conical strip 5, the cover 1 has an inner bore

33. Between the cover 1 and the block of electromagnets 8 there is a gap 34 for the passage of cooling air. To this end, holes 35 are made in the uprights 12, 13, 14, 13.

The drive is mounted as follows.

On the nuclear reactor, a flange 2 is fastened and sealed with its lower part f. Then, a block of electromagnets 8 is mounted on the cover 1 so that the support column 14 with its lower part rests / on the flange. 2 of the cover 1, the ring 18 with its lower (wide) end rests on the upper rack 15, and the inner conical surface 20 of the sleeve 17 was wife with the outer conical surface 21 of the ring 18. When tightening the nuts 25, the sleeve 17 is lowered, while its inner conical surface 20 acts on the outer conical surface 21 of the ring 18 and thereby compresses the ring 18, reducing the width of the groove 19. In turn 33 turn 18 ring th inner cylindrical surface 22 acts on the outer cylindrical surface 23 of the cover

  .

1, thereby squeezing it, creating a preliminary radial force directed to the axis of the cover 1 normal to the surface of the cover 1. Then, the cover mechanism 1 is mounted on the cover 7. Using the squeeze bolts 3, the cover 1 is sealed in its upper part with a plug 4 with conical gasket 5, When tightening the release bolts 3, the conical 1g gasket 5 is compressed, which ensures the tightness of the connector cover. A position sensor 6 is installed and sealed on the plug K. The drive of the regulatory body of the nuclear reactor is ready for operation,

55 As the pressure in the primary circuit of the reactor installation (not shown) increases, a force is created to push the plug 4 out

thirty

40

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case 1, HO, due to the shape of the conical gasket 5, only additional compression of the gasket 5 takes place while maintaining the tightness of the cover-plug connector. At the same time, the radial component of the additional compression force of the gasket, directed from the axis of the case along the normal to the surface of the cover 1, reaches significant values. The specified radial component of the additional compression force and the pressure force of the medium of the primary circuit of the reactor installation are directed to breaking the cover 1 in place of the conical strip 5. The situation is aggravated by the presence of an inner bore 33 of the cover 1 under the conical gasket 5. The specified boring 33 sags the wall of the cover 1, the thickness of which is calculated on the perception of only the pressure of the primary circuit, since the implementation of the cover 1 with a thickened wall leads to a decrease in the pulling forces of the specified drive due to the increase in resistance to magnetic flux, which creates the cover 1 made of non-magnetic steel. to increase the radial dimensions of this drive or to reduce the air gap between the cover 1 and the block of electromagnets 8, which, in turn, impairs the cooling of the electromagnets 9, 10, 11, causing them to overheat or require an increase in the energy consumption for ventilation of the specified drive.

However, violation of the shape and integrity of the cover 1 does not occur due to the fact that the radial component of the additional compression force of the gasket 5 and the pressure forces of the primary circuit are compensated by the preliminary force created by the bandage 16 when tightening the nuts 25.

The operation of the drive of the regulatory body of the nuclear reactor is ensured by supplying in a certain sequence of current pulses to the electromagnets 9, 10, 11, Poles 26f 27t 28, 29, they move under the influence of the electromagnetic field, closing, moving, opening the latches 30, 31, and thereby ensure the movement of the rod 32 or its fixation in a predetermined position. In order to stop the nuclear reaction three times (in emergency protection mode), the electromagnets 9, 10, 11 are de-energized.

the latches 30 and 31 open and the rod 32 with the regulating body is free to fall.

If it is necessary to replace the block of electromagnets 8 at the reactor without decompression of the first loop of the reactor installation, the following operations are necessary. Reduce the pressure in the primary circuit to a value at which there is no violation of the shape and integrity of the cover 1 in place of the bore 33 without the presence of the band 16. Then unscrew the nuts 25, remove the sleeve 17, while the sleeve 17 of the inner conical surface 20 ceases to interact with the outer conical the surface 21 of the ring 18, the ring 18 expands (the width of the groove 19 increases), the compression of the outer cylindrical surface 23 of the cover 1 by the inner cylindrical surface 22 of the ring 18 is stopped. Due to the fact that the minimum inner diameter , The sleeve 17 is selected maximum outer diameter of the sleeve 17 .Free removed from this drive

Then, it is necessary to remove the ring 18 from the cover 1. Since the diameter D of the ring 18 is selected to be larger than the maximum outer diameter n of the position sensor 6, this operation is not difficult. After removing the ring 18, it is necessary to remove the electromagnet unit 8 from the cover 1, due to the fact that the minimum internal diameter D of the electromagnet unit 8 is chosen larger than the diameter D of the outer cylindrical surface 23 of the cover 1 and more than the maximum external diameter D.p of the position sensor 6 , then this operation does not cause difficulties

The installation of the block of electromagnets 8 on the cover 1 and the output of the nuclear reactor to power is carried out in the reverse order.

In order to save time when replacing the block of electromagnets 8 from the cover 1, after unscrewing the nuts 23, it is possible to remove (install) the entire block of electromagnets 8 (together with the bandage 16 and the ring 18).

When installing the block of electromagnets 8 on the cover 1, it is not necessary to have the bandage 16 individually ground to the cover, since the presence on the ring 18 of the groove 19,.

the fit of the inner cylindrical surface 22 of the ring .18 to the outer cylindrical surface 23 of the cover 1.

 The use of the invention will make it possible to eliminate individual grinding of the cover and bandage, which simplifies the manufacturing techniques of such a complex assembly as cover 1; to provide interchangeability of the bandage with the cover, which simplifies the installation and dismantling of the nuclear reactor; increase the “freefall pressure with which you can

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load the case of said drive without the presence of a bandage by eliminating the taper of the cover at the location of the conical gasket; to provide replacement of the block of electromagnets 8 without decompression of the primary circuit; as well as to reduce the time of a simple reactor unit, to reduce the dose of radioactive radiation received by maintenance personnel during installation (dismantling) operations and, in general, to simplify the technology of commissioning and installation works,

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ATTENTED

Order 2377

PROIEV.-IOLIGR. ave, city of Uzhgorod, st. Projectna, A

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. Uzhhorod, st. Projectna, A