JPS6044079B2 - mobile cooling device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a mobile device for cooling the inner surface of a pipe.

Stress corrosion cracking in the weld heat-affected zone of stainless steel pipes for nuclear reactors has long been widely recognized as a serious problem.

October 1976, assigned to the same assignee as the present invention.
U.S. Pat. Otherwise, effective methods for substantially reducing the amount are described. Such a method involves forming a secondary weld or overlay weld that extends across the steel pipe joint and at the same time bridges both sides of the steel pipe joint beyond the axial ends of the primary weld heat affected zone on the inner surface of the pipe. is installed outside the steel pipe joint. It is preferable to install such overlay welds while the inner surface of the steel pipe is being cooled with water or other cooling liquid. It has now been found that the inner surface of a vibrator can be cooled simply and effectively by implementing the present invention.

That is, the present invention provides a new and improved mobile cooling system that is particularly suitable for cooling the inner surface of a vibrator during the installation of overlay welds. In the use of such devices, it is customary for the coolant to be supplied in a highly turbulent flow to the area where the overlay weld is located. Generally speaking, the mobile device of the present invention for cooling the inner surface of a vibrator comprises: (a) an elongated semi-rigid device connected to a source of high-pressure cooling fluid and capable of passing the cooling fluid along an axial direction; a conduit; (b) a semi-rigid pressurizable first inflation member coupled to and in fluid communication with the conduit; and (c) a pressurization inflatable member spaced apart from the first inflation member. (d) a plurality of holes connected to and in fluid communication with the first and second expansion members for radially outward flow of the cooling fluid; one inflatable member can be inflated to fit substantially the entire inner periphery of a portion of the vibrator, while the other inflatable member extends radially outward from the outer surface of the vibrator. Thrust in the direction.
It has a plurality of protruding members spaced apart from each other so as to extend and cross the axis of the device, and therefore, when inflated, the protruding members contact only a portion of the inner circumference of the vibrator, thereby reducing the distance between the vibrator and the vibrator. It is characterized in that a flow path is formed in the.

A thorough understanding of the practice of the invention may be obtained from the detailed description of the invention when read in conjunction with the accompanying drawings.

It should be noted that similar elements in both figures are represented by the same reference numerals. Referring to the drawings, especially Figure 1,
Mobile cooling device 10 is shown being advanced in the direction of arrow 12 along a tortuous path within vibe 14 that includes adjacent S-shaped bends 16 and 18.

Such vibes are, for example, 304 stainless steel tubing used in boiling water systems of nuclear reactors. Such a vibrator has a butt weld 20 to which an overlay weld 22 (FIG. 2) is to be installed, but during welding work for this purpose, the temperature of the inner surface of the vibrator 1 typically rises to 300'F or more. . Therefore, if the inner surface of the vibrator is not effectively cooled, susceptibility to stress corrosion may increase. Cooling system 10 includes an elongated semi-rigid conduit 24, one end of which is equipped with a fitting 26 for connecting conduit 24 to a source of high pressure coolant (not shown). The high pressure cooling liquid in this case is preferably 10 to 15
Gauge pressure of 0 pSi or higher and 35-80
Any water having a temperature of 'F is sufficient. A first inflation member 28 is coupled near the other end of the conduit and is in fluid communication with the conduit 24 through an opening formed by a neck 30 mounted thereon. The cooling device 10 also includes a conduit segment 34 connected to the first expansion member 28 and in fluid communication with the first expansion member 28 through an opening formed by the neck 32. Additionally, a second inflation member 36 spaced apart from the first inflation member 28 is connected to the other end of the conduit segment 34 through an opening formed by the neck 38. 34 and has a free circulation relationship. Some of the connections described above may be formed by any suitable fastening means, such as mechanical clamps, strong adhesives, and the like. Otherwise, the entire device or any adjacent elements thereof may be of monolithic construction. As shown in FIG. 1, the cooling device 10 is moved back and forth within the vibrator with the expansion member in a deflated state, so that the central portion of the device along the axial direction of the conduit segment 34 is located at the position to be cooled ( For example, the vibe area before and after the butt weld 20 as shown in Figure 2)
It can be arranged to reach.

As a result of the semi-rigid structure of the conduit 24 and the first inflatable member 28, a good balance between flexibility and rigidity is achieved;
The device can be moved along tortuous conduits and at the same time does not become entangled. It should be noted that the conduit segment 34 may also be of semi-rigid construction.
Furthermore, cooling device 10 preferably also includes means for detecting the presence of the device at a predetermined location within the vibrator.

When used within a non-magnetic vibrator, effective detection means include one or more magnets placed on the device.
For example, in the illustrated coupling, magnets 40, 41, 4
2 and 43 are embedded. On the other hand, a compass or other magnetic sensing means is maintained near the outer surface of the vibrator at a predetermined distance from the butt weld 20 (e.g., line 4--4 in FIG. 2). If the compass pointer swings upright toward the vibrator, you know that a magnet is present in the plane of the pointer. In this way, the position of the cooling device 10 within the vibrator can be determined accurately. After the cooling device 10 is properly positioned along the axis of the vibrator, the coupling 26 is connected to a source of high pressure cooling fluid (eg, water).

High pressure cooling fluid is then flowed into conduit 24, which causes expansion members 28 and 36 and conduit segment 3 connecting them to flow.
Satisfy 4. As the flow continues, the high pressure coolant 44 inflates the expansion members 28 and 36, resulting in an expanded state as shown in FIG. As shown in FIGS. 2 and 4, when the first inflatable member 28 is inflated, it comes into close contact with almost the entire inner periphery of a part of the vibrator 14.
4, the device is removably fixed. The second inflatable member 36 includes a plurality of projecting members or protrusions 46 projecting radially outwardly from an outer surface thereof.
47, 48, 49, 50 and 51 are equipped.

The projections are spaced apart transversely to the axis A-A of the device. In other words, the second inflatable member 36 has at least a portion of each protrusion perpendicular to the axis.
It exists on the maximum outer circumference of . Second expansion member 36
If it is expanded by high-pressure cooling liquid, the protrusions arranged at intervals come into contact with only part of the inner circumference of the vibrator 14, so that flow channels 52, 53, 54, 55 are created between the vibrator and the vibrator.
, 56 and 57 are formed. Conduit segment 34 is provided with a number of holes 58 passing through the annular wall.

Preferably, such holes are uniformly distributed along the axial direction and circumference of the conduit segment 34, as shown in FIG. As a result, a jet of high pressure coolant is ejected generally radially outwardly from the holes. The resulting highly turbulent cooling bath typically causes the first expansion member 2 to
The interior area of the vibrator from 8 to the second inflation member 36 is almost completely filled. The overlay weld portion 22 may be installed while the cooling liquid continues to flow into the cooling bath.
The inner surface of the vibrator in contact with such a cooling bath is effectively kept at a lower temperature, and the coolant, which has taken away the heat from the welding operation, is discharged through channels 52, 53, 54, 55, 56 and 57. Furthermore, as a result of the cooling bath consisting of a highly turbulent flow,
The formation of steam pockets adjacent to the inner surface of the vibrator to be cooled is almost completely prevented. Expandable members 28 and 36 are preferably expandable into a configuration that is generally symmetrical about the axis A--A of the device, as shown in FIGS. 2-4.

Because of this symmetry, the axis of the conduit segment 34 is aligned with the vibe 14.
, and thus more uniform cooling of the vibrator 14 will be achieved. After the cooling operation is complete, the device may be disconnected from the source of cooling fluid, the cooling fluid may be drained to deflate the expansion member, and the device may then be removed from the vibrator.

The various elements of the device of the invention can be made from any suitable materials. For example, inflatable members 28 and 36 may be made from a resilient material such as rubber. The diameter of the hole 58 can be any suitable value, for example from 0.05 inch or less to 0.1 inch.
It can take values up to 0 inches or more, preferably about 0.07 inches. In addition, protrusions 46, 47, 48, 49, 50
and 51 has a radial thickness of, for example, about 1132 to about 1
It may be 18 inches, preferably about 1116 inches. It will be appreciated that the detailed description of the invention is merely illustrative of the practice of the invention and that many changes may be made without departing from the spirit and scope of the invention.

[Brief explanation of the drawing]

Fig. 1 is a partial side view showing a cooling device according to an embodiment of the present invention being advanced to a use position in a vibrator in a partially deflated state, and Fig. 2 is a partial side view showing a cooling device constituting an embodiment of the present invention being advanced to a use position inside a vibrator. FIG. 3 is a partial cross-sectional side view showing the cooling device of FIG. and FIG. 4 is a cross-sectional view taken along line 4--4 in FIG.

Claims (1)

Claims: 1 (a) an elongated semi-rigid conduit connected to a source of high pressure coolant and capable of axially passing said coolant; (b) connected to said conduit and connected thereto; a semi-rigid, pressure-expandable first expansion member (c
) a second inflatable member spaced apart from the first inflatable member; and (d) coupled to and in fluid communication with the first and second inflatable members. and comprising a conduit section having a number of holes for the radial outward flow of said cooling fluid, one of the expansion members being in close contact with substantially the entire inner periphery of the portion of the pipe when expanded. whereas the other inflatable member has a plurality of protruding members projecting radially outwardly from its outer surface and spaced apart from each other transversely to the axis of the device, so that the inflatable member A movable device for cooling an inner surface of a pipe, wherein the protruding member contacts only a portion of the inner circumference of the pipe, thereby forming a flow path between the projecting member and the pipe. 2. The device of claim 1, further comprising means for detecting the presence of the device at a predetermined location within the pipe. 3. The device of claim 2, wherein said means for detecting the presence of the device includes a magnet disposed on the device. 4. The device according to claim 1, wherein the one expansion member that can come into close contact with substantially the entire inner periphery of a portion of the pipe when expanded is the first expansion member. 5. Claim 1, wherein the first and second expansion members are expandable into a shape symmetrical about the axis of the device.
Apparatus described in section.