JPH02122094A - Tube-like rod for treating innerface of tube - Google Patents

Abstract

PURPOSE: To apply metallic plating on the required parts in a small-bore metallic tube by inserting a tubular rod to which hermetic sealing devices are built at specific intervals into the tube and feeding a plating liquid to the inside surface of the part to be treated of the tube at the time of applying the corrosion resistant metallic plating to the specific parts on the inside surface of the tube.

CONSTITUTION: The specific range of the inside surface of the tube 20 is plated and coated with Ni, etc., as the corrosion resistant metal in order to powerfully prevent the corrosion during working of the tube, etc., of the steam generator of a pressurized water type nuclear reactor. The tubular rod 2 having the hermetic sealing assemblies 5, 6 for separating the specified range in the tube 20 from an adjacent area is inserted into the tube 20 to be treated for this purpose. The rod is provided with an annular piston 26 for moving the hermetic sealing assemblies 5, 6 toward the axial line 4 of the rod 2 and is provided with a device 29 for compressing a flexible annular seal 32 and seal 32 between this piston and a radial supporting flange 33 or expanding both seals in a radial direction. The plating liquid is supplied to the specific range in the tube 20 so as not to leak to the adjacent part, by which the plating is applied on the tube.

COPYRIGHT: (C)1990,JPO

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is a tubular rod for treating the internal surface of a tube with a liquid supplied through the rod, the tubular rod incorporating a sealing device disposed about the tubular body of the rod. Regarding.

Tubular shaped rods are known which effect the circulation of the treatment liquid in contact with the area of the tube to be treated and optionally supply an electric current for electrolysis of the liquid in that area.

In particular, rods of this type are used to apply metal coatings, such as nickel plating, to the interior of the tube.

Steam generators in pressurized watercolor reactors in the case of very long and small diameter tubes, for example with an internal diameter of 0.02 meters and a length of two straight sections of 10 meters or more. In the case of tubes, it is necessary to apply a metal coating, such as nickel plating, to certain areas of the tube to increase resistance to corrosion during operation.

This type of treatment is carried out on a section of the tube located at the outlet face of the tube plate, ie at a short distance from one of the tube inlets, for example at a distance of less than 1 meter.

However, it is desirable to treat the interior of the tube for one of the straight sections at any distance from the inlet of the tube at the same height as the inlet face of the tube plate.

Rods for the treatment of the internal surfaces of the tubes of steam generators are equipped with the following methods: to separate (isolate) the part of the tube where the treatment takes place from the adjacent area, in order to avoid leakage of the electrolyte from the sides of the area to be treated. ) must be provided with a sealing device.

Processing rods of this type incorporating sealing devices have been fairly commonly used for processing sections of tubing located within or near tube plates. The processing rod is supported and centered within the tube to be processed by its base and has a plurality of centering elements configured to be introduced into the tube adjacent to the tube to be processed. The base member of the rod incorporates within the rod means specifically for distributing the fluid to be treated.

This type of treatment rod with associated sealing devices has a complex structure and consists of a large number of parts, with the result that it is difficult to carry out correct operation and leakage of electrolyte can occur at both ends of the area to be treated. There is a possibility that this may occur.

Furthermore, devices are known which are capable of treating one arbitrary area of a straight section of the tube and which incorporate a set of places that must be placed in the tube when the rod is introduced into the tube.

The present invention therefore treats the internal surface of the tube with a liquid supplied through the rod, disposed around the tubular body of the rod and covering a portion of the internal surface of the tube in adjacent areas of the tube along its length. The present invention provides a tubular rod incorporating a sealing device separating the area, which has a simple construction and is able to achieve good liquid sealing on both sides of the area to be treated.

To this end, the sealing device has two assemblies spaced apart along the length of the rod, each of the assemblies being mounted for axial movement around the body of the rod. at least one flexible annular seal disposed about the body of the rod and axially interposed between one end of the piston and a radial support flange; means for remotely controlling the piston to displace the piston.

Next, the present invention will be explained with reference to the drawings.

In Figures 1, 2a and 2b, a first form of construction of a nickel-plated rod 1 is shown, which can form a coating inside the tube. This nickel-plated rod 1 has a completely rigid structure, allowing the actual rod 1a to be introduced into the tube and the distribution of fluid into the rod and being rigidly connected to one end of the actual rod 1a and forming a tubular shape. The main body 2 has a tubular shape and is composed of a shaped casing and an assembly of parts. The sealing device for the rod consists of two sealing assemblies 5 and 6 arranged around the body 2 and spaced apart in the direction of the axis 4 of the rod 1a.
The main body 2 is provided with an irregularly shaped head 7 at one end thereof. The rod 1a is also provided with a ring 9 which is mounted above the distribution block 1b in a sliding manner on the external surface of the body 2 of the rod and which is locked axially by a screw 8. The ring 9 comes into contact with the inlet face of the tube plate at the same height as the inlet end of the tube to be treated, and by adjusting the length of the rod 1a introduced into the tube, the length of the rod 1a introduced into the tube can be adjusted. The active area of the nickel-plating rod between sealing assemblies 5 and 6 may be positioned to coincide with the area of the tube.

The distribution block 1b is internally machined to form a duct 10 for supplying electrolyte to the rods and a duct 11 for collection of the electrolyte circulating through the rods.

The ducts 10 and 11 are led to the end face 12 of the block 1b at a connection point such as 13 and can be connected to a flexible tube.

The duct 10 is connected to the outer annular duct 14 of the tubular body 2 inside the block 1b. The annular duct 14 communicates with the exterior of the body 2 through an annular opening 15 formed by two members 16 and 17 arranged immediately above the sealing assembly 6 and having frustoconical surfaces. The member 16 is fixed to the tubular casing 2b of the main body 2i, and the member 17 is fixed to a sleeve 18, which forms the outer wall of the annular channel 14 and is connected at the bottom to a thick-walled sleeve 19. The sleeve 19 is fixed to the distribution block 16 at the bottom. The assembly of casings 2a and 2b and tubular parts 18 and 19 constitutes tubular body 2. At the top and bottom of the sealing assembly 5, the casings 2a and 2b are provided with through holes 21.
is provided, this through hole 21 extending the interior of the tube 2a into the space between the active part of the rod 1a between the sealing assemblies 5 and 6 and the inner surface of the tube 20 on which the coating is to be formed. Communicate.

The electrolyte carried into the annular channel 14 via the supply conduit 1o flows out of the body 2 of the rod via the annular opening 15. The liquid contacts the internal surface of the tube over the entire length of the area to be treated and is then collected inside the tube 2a via the opening 21.The electrolyte then passes through the central duct formed by the tubular casing 2a. and returns to the entrance of the duct 11 via the duct 11. An electrical potential is brought to the tube 20 by the electrodes. Electrolysis of the liquid flowing along the inner wall of the tube 20 is performed by a treatment zone to deposit a layer of coating nickel on the inner surface of the tube.

Sealing assembly 5 and 6 of nickel-plated rod 1
This achieves complete containment of the electrolyte and prevents leakage on both sides of the area of the tube to be treated, as described below.

As shown in FIG. 2a, the body 2 of the rod has an 0 member 24 supporting at the top an end member 24 to which the head 7 is fixed.
and the head 7 form an annular chamber 25 between them, in which a piston 26 of annular configuration is dimensioned to move in the direction of the axis 4 of the rod.

The piston 26 is sealed in the annular chamber 25 by a ring seal 27. The annular chamber 25 is connected to the end member 24
It communicates with a duct 28 machined inside the rod, further communicates with a tube 29 in the direction along the axis of the rod, and is connected to a nozzle 30 at the bottom of the distribution block 1b,
The nozzle 30 is connected to compressed air supply means by a flexible hose.

When compressed air is admitted into the chamber 25, the piston 26 is forced axially downwards into abutment against a flexible annular rubber seal 32 through a ring 31 of plastic material, the rubber seal being in contact with the ring 31 and At the end opposite to the end facing the piston 26, it abuts a shoulder 33 machined into a member 34 fixed to the body 2 of the rod.

The bottom of member 34 defines a radially projecting flange against which flexible annular seal 32 abuts.

When the piston 26 is actuated by compressed air, the seal 32 receives the compressed air and expands radially, causing the tube 2
0 in a sealed manner.

In FIG. 2b, the sleeves 18 and 19 form an annular chamber 35 between them, the axis of the annular chamber 35 being
The annular chamber surrounds a piston 36 which is sealingly and movably mounted within the chamber 35 by means of a ring seal 37. The chamber 35 is supplied with compressed air by a duct 39 connected to a chamber formed in the distribution block 1b and led to the nozzle 30.

Therefore, pistons 26 and 36 are compressed.

When air is supplied to the nozzle 30, it is activated at the same time. The piston 36 now abuts a flexible annular rubber seal 42 attached to the external surface of the sleeve 18 by a ring 41 of plastic material. The sleeve is provided with a top shoulder 43 which constitutes a radial support flange for the end of the annular seal 42 opposite the end facing the ring 41 and piston 36. Displacement of piston 36 in an upward direction by the action of compressed air causes compression and radial expansion of seal 42, which comes into sealing contact with the interior surface of tube 20.

After the rod 1 to be nickel-plated is placed in position on the tube, the supply of compressed air from the nozzle 30 completely isolates the area of the tube 20 to be nickel-plated as described above.

FIG. 3 shows a variant of the structure of the sealing devices 5 and 6, and corresponding parts between FIGS. 2a and 2b and FIG. 3 are given the same reference numerals.

In this variant embodiment, the respective end surfaces 45 and 46 of the pistons 26 and 36, the respective support surfaces 47 and 48 of the member 34 and the sleeve 18 are beveled, the beveled surfaces facing each other in pairs leaning in different directions.

When compression is applied, pistons 26 and 36 come into contact with resilient seals 32 and 42, respectively, without intervening rings of plastic material.
Annular pistons 26 and 36 with beveled ends compress resilient seals 32 and 42 held by beveled shoulders 47 and 48. This causes compression of the resilient seals, which causes the central portions of these seals to expand radially into contact with the tube 20.

In the modified embodiment shown in FIG. 3, the holes 15 and 21 for the electrolyte flow path are made slightly differently than in the embodiment shown in FIGS. 2a and 2b. However, the circulation of the electrolyte from the duct 14 around the air duct 29 and back through the central part of the annular body 2 is identical to that described with reference to Figures 2a and 2b.

At the end of the nickel plating operation, the supply of electrolyte to the rod is stopped and if any debris or waste remains in the tube at the end of the nickel plating operation,
These things are collected by a top cylindrical cavity 50 and a duct 51 machined into the distribution block 1b,
The duct 51 has a nozzle 5 for the discharge of debris or waste.
It is connected to 2.

In FIG. 4, the nickel-plating rod is shown in operational position within a tube secured to the tube plate 60 of a steam generator of a pressurized water expansion reactor.

A tube plate 6 that is flush with the end of the tube 20
Below the inlet surface 60a of 0, the steam generator has a water container 6
1 is provided and a test opening or manifold 62 is located within the water container 61.

Mounted inside the water container 61 is a carrier device having an arm 64, to the end of which a carrier 65 is fixed, and to the carrier 65 the end of a flexible guide hose 67 is attached. A ring 66 is connected.

A carrier device 63 of conventional type allows the carrier to be displaced to correspond to the inlet end of each of the tubes to be treated.

The nickel-plating rod 1 has a rigid end portion 70 which is constructed similarly to the rigid rod portions shown in FIGS. 2a, 2bll and 3.

This rigid part has two sealing assemblies 75.
and 76 are provided, the construction and operation of which are identical to that of the sealing assemblies 5 and 6 previously described.

The nickel-plated rod 71 shown in FIG. 4 is also provided with a distribution block 71b that is the same as the distribution block 1b shown in FIG. This distribution block 71b is fixed to a support 73 arranged outside the water container 61, and at the end opposite to the carrier 65 and the end of the flexible guide hose 67 where the tube inlet is arranged the water is fixed to the container.

The rigid part 70 of the nickel-plated rod is connected to the distribution block 71 by a body 72 consisting of a coaxial flexible duct.
b to enable the supply of fluid and current to the rigid part of the rod to be nickel plated.

The structure of the deformable body of the nickel plated rod, such as body 72, is described below with reference to FIGS. 6 and 7.

The apparatus shown in FIG. 4 allows the nickel plating operation to be controlled from outside the water container by introducing the nickel plating rod into the tube of the steam generator. The operation is carried out by remote control of the carrier device 63, remote controlled introduction of the rod into the desired position and control of the tube coating operation from outside in the distribution block 71b.

By using a suitable length of visibility body 72, it is possible to perform nickel plating on a straight section of tube at any height above tube plate 60.

As shown in FIG. 5, a rod 80 is plated with nickel.
The modified configuration of the sealing assemblies 5 and 6 is introduced into the tube 20 in the operating position.

The nickel-plating rod has a tubular shaped body 82 which is fixed at the top to an end member 84 and connected at the bottom to a sleeve 85 concentric with and external to the tube 83. The tube 83 and the sleeve 85 form an annular duct 89 through which the electrolyte can pass.

Tube 83 and sleeve 85 have a common axis 4 that is the same as the axis of the tube when nickel-plating rod 80 is in the operating position within tube 20 .

Tube 83 and sleeve 85 begin at a point below seal assembly 86 and include a flexible tube connected at one end to the rigid portion of body 82 of rod 80 and at the other end to a fluid distribution block (not shown). Hoses and parts of their length can be replaced.

An embodiment utilizing a flexible hose allows the nickel plating rod to be introduced and controlled from outside the water container of the steam generator.

Attached to the top member 84 of the body 82 of the rod is a profiled head 87 fixed to a piston 88. head 87
and 84 is provided by a seal 90.

A coil spring 91 is interposed between the piston 88 and a member 84 forming part of the tubular body 82 of the rod. The spring connects the piston 88 to the first annular elastic seal 9
2a, and the seal 92a is pressed against the support spacer 93.
The pressure of the piston 88 is transmitted to the second annular seal 92b.

The second annular seal 92b is a nickel-plated rod 8.
Radial flange 9 of sleeve 95 constituting electrode 0
4.

The sleeve 95 is the main body 82 of the rod to be nickel plated.
It is attached so that it can freely slide around the tube 83 of. The bottom of the sleeve 95 has a radial flange 96
comes into contact with the first annular seal 97a through the
The first annular seal 97b is the tube 83 of the rod body 82.
It abuts against the end of the sleeve 85 fixed to.

The pressure exerted by the piston on the annular seals 92a and 92b due to the action of the spring 91
5, so that the sleeve 95 seals the pressure 9.
Add to 7a and 97b.

For this reason, all annular seals 92a, 92b, 97a
and 97b are simultaneously compressed by the action of spring 91 and come into contact with the inner surface of tube 20. The radial deformation of these annular seals in the case of electrode 95 provides leak protection for the processing area located between the sealing assemblies.

The electrolyte is introduced into the tube outside the body 89 of the rod via an annular duct 89 communicating at its top end with an opening 100 passing through the electrode 95. The electrolyte circulates between the electrode 95 and the inner surface of the tube 20 before entering the opening 101 through the electrode 95 and the tube 83 of the body 82 of the rod to be nickel plated. 83 and back to the distribution block connected to the end of the nickel plated rod 80 (not shown).

The nickel-plating rod 80 also incorporates along its axis a compressed air supply duct 103 connected to the internal bore of the end member 84 of the body 82, the duct connecting the head 87 and the end of the member 84. It is guided into a chamber 104 formed between the two. Chamber 104 is configured to prevent leakage by seal 90. compressed air tube 10
3 and 104, head 87 and piston 88 move upwardly, compressing spring 91 and releasing the pressure applied to the annular seal.

Support pressure is no longer applied to electrode 95 by annular seal 92b.
The electrodes relieve the pressure acting on bottom seals 97a and 97b.

Thus, the nickel-plating rod 80 can be displaced within the tube 20, for example for removal from the tube, and the seal remains uninflated as long as compressed air pressure is maintained within the chamber 104.

The device shown in FIG. 5 can be referred to as a positive locking device. The reason is that the leakage prevention between the seal and the inner surface of the tube is automatically achieved by the action of the spring 91, and it is necessary to apply pressure to compress the seal and separate it from the inner wall of the tube 20. It is from.

6 and 7 show the construction of the bottom portion of a nickel-plated rod of the type shown in FIG. 5, i.e., of the positively fixed type. Components in FIGS. 6 and 7 that are identical to components in FIG. 5 have been given the same reference numerals.

The tube 83 of the tubular body 82 of the rod is connected at the bottom to a connecting member 106, which has an end piece 107 with ## connecting the end piece 107 to the sleeve 85. The sleeve 85 connects the connecting member 10
8 at the bottom. two connecting members 10
6 and 108 connect the rigid parts of the rods at the locations of tubular members 83 and 85 to flexible hoses 109 and 11.
0 respectively. Concentric hoses 109 and 110 constitute a flexible hose similar to body 72 shown in FIG. connected.

A flexible hose 103 for supplying compressed air for unlocking the sealing device of the positive fixed rod is fixed to the connecting member 106 by means of fingers 111 .

The electrolyte is introduced into the rigid part of the rod via a tubular duct 89 formed between flexible hoses 109 and 110. The electrolyte is collected within the central portion of tube 83 and further within the interior space of hose 109.

The processing rod of the present invention has the advantage of incorporating a simple sealing device that is extremely reliable to operate.

This sealing device is extremely easy to control remotely and does not require substantial changes to the structure of the rod.

The processing rod can be controlled remotely and does not require direct intervention near the tube to be processed.

The invention is not limited to the embodiments described.

Thus, it is also possible to envisage sealing compression pistons having shapes different from those described and actuated by other mechanical, hydraulic or pneumatic means than those described.

The structure of the rod may be different and may have an interlocking rigid portion and a visible portion with a length adapted to the shape and dimensions of the tube to be treated.

If&, the processing rod of the present invention is used not only for nickel plating or forming other metal coatings on the inner surface of the tube, but also for example cleaning, electrolytic or chemical treatment or treating the inner surface of the tube with a reaction solution. It can also be used for treatments other than the coating, such as other surface treatments necessary to contact the coating.

[Brief explanation of the drawing]

FIG. 1 is a front view, partially in section, of a rod to be nickel plated. Figures 2a and 2b are cross-sectional views of the nickel-plated rod of Figure 1 in each of the rod seal assemblies; FIG. 13 is a cross-sectional view of a rod to be nickel plated according to a modification of the embodiment shown in FIGS. 1, 2a and 2b. FIG. 4 is a front view of a nickel-plated rod with a flexible part in the working position of a tube of a steam generator; FIG. 5 is a front view, partially in section, of a nickel-plated rod showing a modified embodiment of the sealing device; 6 is an axial cross-sectional view of the portion of the nickel-plated rod having a flexible portion shown in FIG. 5; FIG. FIG. 7 is a cross-sectional view taken along line 7--7 of FIG. DESCRIPTION OF SYMBOLS 1... Rod to be nickel plated, 1a... Actual rod, 1b... Distribution block, 2... Main body, 5.6... Sealing assembly, 7... Head, 9... -Ring, 10...Duct, 18...Sleeve, 26...Piston, 36...Piston.

Claims (1)

[Claims] (1) Liquid supplied through the rod to the tube (20
) for treating the internal surface of a tube (20), the tubular rod is arranged around the tubular body (2, 82) of the rod and covers a portion of the internal surface of the tube (20) in adjacent areas of the tube along its length. It incorporates a sealing device that can be separated from the rod (1, 70, 80).
having two assemblies (5, 6) spaced apart along the length of the rod, each of the assemblies being mounted for axial movement about the body (2, 82) of the rod. A piston (26, 36, 88, 95) of annular shape, arranged around the body (2, 82) of the rod and axially connected to one end of the piston (26, 36, 88, 95) and a radial support flange ( at least one flexible annular seal (32, 42, 92a, 9) interposed between
2b, 97a, 97b) and seals (32, 42, 92
actuating means (29, 25, 35, 91, 103, 10) for actuating and axially displacing the pistons for compression and radial expansion of
4) A tubular rod comprising: (2) A tubular rod according to claim 1, wherein the actuating means comprises an air ram consisting of a chamber (25, 35) in which a piston (26, 36) is slidably mounted and in which the rod A tubular rod, characterized in that pressure fluid is supplied from one end of the tubular rod via a compressed air duct (29) arranged along the length of the body (2) of the tubular rod. (3) A tubular rod according to claim 1, wherein said actuating means for actuating at least one piston of the sealing assembly (5, 6) comprises a portion of the body (82) of the rod and a portion of the piston (82).
a coil spring (91) interposed between one end of 8);
A tubular rod characterized in that it is (4) In the tubular rod according to claim 3, the piston (
88) is a rod body (82) which is fixed to the hollow member (87) closed at one end and which engages the tube (20) during operation.
) is axially slidably mounted on one end of the member (
87) together with the rod body (82), the spring (
a chamber (10
4) A tubular rod characterized by forming. (5) A tubular rod according to any one of claims 3 and 4, in which the piston (92) for one (6) of the sealing assemblies, i.e. the second assembly, is arranged on the body (82) of the rod. consisting of a sleeve (95) mounted for axial sliding movement at and interposed between the other sealing assembly (5), i.e. the first assembly, the first assembly having a radius of The seals (97a, 97b) of the second assembly come into abutment against the directional flanges and the seals (97a, 97b) of the rod body (
82), characterized in that the pistons (87, 95) of the two sealing assemblies (5, 6) have a spring (91) as a common actuation means. (6) The tubular rod according to any one of claims 1 to 5, wherein the tubular rod includes a tubular portion (1a) constituting the actual rod, and a duct (1a) connected to one end of the tubular portion (1a) and distributing fluid into the rod. 10, 11, 29) and a distribution block (1b). (7) A tubular rod according to claim 6, in which the distribution block (1b) is connected to the rod (1a) by the flexible body (72).
) a tubular rod, characterized in that it is connected to a (8) A tubular rod according to any one of claims 6 and 7, in which the distribution block (1b) comprises a tube (20
) at least one duct (10, 11) for the distribution of treatment liquid of the rod and at least one duct (2) supplying the rod with pressurized fluid for actuating the sealing assembly (5, 6).
9) A tubular rod comprising: