JPS63120906A - Clamping device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

BACKGROUND OF THE INVENTION The present invention relates to a clamping device for sealing an instrumentation boat or instrumentation pipe connection port associated with a nuclear reactor system, and more particularly to a clamping device for sealing an instrumentation boat or an instrumentation tube connection port associated with a nuclear reactor system, and in particular for sealing a reactor vessel lid penetrator and a thermoelectric A high quality clamping device for maintaining a proper seal at the interface between paired instrumentation columns.

Due to the various hazards associated with the operation of nuclear power plants, the design and quality standards for nuclear reactor equipment are very high and stringent, so even problems that can be directly solved in a non-nuclear environment are often In relationships, this is a difficult issue and requires attention.

For example, many industrial environments require R to measure and monitor pressures, temperatures, and other parameters of various work equipment. In the environment of a nuclear power plant, such monitoring can be extremely dangerous due to the potential for leakage of radioactive materials. Therefore, in a nuclear power plant environment, it is essential that the instrumentation used to make the above measurements be precisely designed to prevent the aforementioned leaks.

Although the possibility of leakage of radioactive materials from a nuclear power plant is reduced as much as possible by the containment building that encloses the nuclear steam supply system, the working conditions within this containment building are such that even during normal reactor operation, It is a danger. This is especially true during reactor refueling, as high background radioactivity and high airborne particulate radioactivity are present within the containment building.

The maximum amount of LA that a worker can be in these areas during reactor operation and refueling is set by safety standards. Many of the similar locations are hazardous during refueling due to high ambient temperatures. Also, in most situations these areas are not easily accessible and safety platforms are not available, so it is important to reduce as much as possible the exposure of workers to such hazardous working conditions. It would be desirable to provide a clamping device that can be assembled quickly and easily,
It is also economical to quickly and efficiently repair or replace instrument boat clamping devices, since it reduces nuclear power plant downtime and reduces the cost of providing replacement power. Highly desirable.

In order to understand the invention more clearly, one typical interface of an instrument boat is shown in FIG. As shown in the figure, the lower object, i.e. the conduit or flange 10
is coupled or otherwise attached to a container (not shown) containing the parameter to be measured, while the upper body, i.e. conduit or flange 11, is coupled or otherwise attached to a device (not shown) for measuring the parameter. It is attached by a method.

In particular applications, such as nuclear power plants, the lower portion of the flange 10 is threaded onto and welded to the lead-through of the lid. Flanges 10 and 11 are primarily tubular in shape and have upper and lower surfaces, respectively, designed to engage each other in sealing relation with respect to gasket 12.

Effectively compressing the gasket 12 to compress the flange 10.11
Preferably, the clamping device applies axial pressure to the flanges 10 and 11 in order to seal the interface therebetween.

For the interface of the instrument boat shown in FIG. While applying the force, it is necessary to apply substantially the same downward axial force to the flange 11.

Sealing between flanges 10.11 is an important safety issue when designing reactors for nuclear power plants.

As will be appreciated by those skilled in the art, such flange interfaces are typically located in areas of high radiation levels and high process temperatures in nuclear power plants. For these special situations, flange 1
A high quality clamping device capable of sealing interfaces between 0.11 and 0.11 mm is not only desirable but necessary. In many applications, it is desirable to construct such clamping devices from high strength materials. It is also very important for worker safety that the clamping devices used to seal such interfaces be quick and easy to install and remove.

A conventional clamping device that has been used heretofore is indicated generally at 20 in FIG. This clamp device 2
0 consists of three essentially identical body sections 138, 13B and 13C, each body section having a span of approximately 11 degrees.
There is a gap 15 of about 10° between the 0 body parts at 0°. Each end of the 0 body parts 13^, 13rl, and 13C has a flange part, and this flange part is used to connect the main body parts to each other. It is installed. That is, the cap screw 14 as shown
or other retaining means are passed through the flanges to hold the body portion in a generally ring-like manner, and such clamping devices are assembled to the flanges 10 and 11.

Next, a case will be described in which the clamp device 20 is used on the interface of an instrumentation boat of a nuclear reactor vessel as shown in FIG. Because of its shape and weight, the clamping device 20 of FIG. At least two operators are generally required to assemble the clamping device 20. Jf
Since the cooling shroud and other equipment are fixedly installed above the lid of the X reactor vessel, operators can only access the flanges 10 and 11 from the outside in the radial direction of the reactor vessel lid. , the particular operating procedure of the clamping device that has been used to date requires the use of an axial loading device that seats on the gasket before using the clamping device. Such axial loading devices are generally heavy and unwieldy, their installation is very difficult, and the necessity of this axial loading device limits the available working space, thus limiting the clamping device 20. It becomes difficult to assemble. Once the axial loading device is properly positioned, each gap 15 between the body parts should be spaced to obtain approximately -like contact and pressure on the flanges 10 and 11 and to minimize bending of the cap screw pedicle. Careful adjustments must be made to achieve substantial equality. Approximately 66+s/Kg (100ft/lb) for the cap screw 14
It is normal to apply torque up to A fairly long torque device would be required to apply torque to this extent.

It should be noted that in many cases over-torquing the cap screw 14 will result in over-compression of the gasket 12; for a gasket, over-compression has an undesirable and significant effect on its sealing ability. Prior art glue and lamp devices were commonly used as a means of limiting the clearance between the flanges to prevent over-compression of the gasket as described above. As is clear from the above description, the procedures and equipment required for assembly of the clamping device [20] were time consuming and had a significant potential for improper installation. Such drawbacks are that the clamping device must be installed in an inconvenient and dangerous position, requiring the operator to be tethered with ropes or other safety equipment, and requiring the operator to wear a mask, heavy gloves, and radiation-resistant clothing with a gas mask. In cases where it is considered necessary to wear obstructive equipment such as
It becomes even more noticeable.

Although it is known to use articulated clamping devices to overcome some of the drawbacks mentioned above, conventional articulated clamping devices have been found to suffer from the open space associated with using such clamping devices in a nuclear power plant environment. And it is not possible to completely solve the drawbacks. For example, articulated clamping devices that have been used to date have not addressed the significant problem of potential gasket compression, thereby requiring the use of clearance limiting means. Although such clearance limiting measures may have been adequate for their intended purpose, they are not suitable for many nuclear power plant systems due to existing space limitations and due to existing instrumentation. The shape of the boat flange precluded the use of clearance limiting means.

It is an object of the present invention to provide a quick, safe and easy to install lamp device and clamping device for use in a nuclear power plant environment.

Another object of the invention is to provide a clamping device that generates a circumferentially uniform ramp clamping pressure without the aid of an axial loading device.

Yet another object of the invention is to provide a clamping device that prevents overcompression of the sealing gas get without the need for clearance limiting means.

Another object of the present invention is to provide a clamping device that reduces as much as possible the time that workers are exposed to a hazardous working environment and the number of workers that are exposed to such exposure.

Still another object of the present invention is to provide a clamping device that can be installed and removed by applying a relatively small torque without using any special tools.

According to one embodiment of the present invention, a clamping device achieving the above-mentioned and other objectives comprises a plurality of intermediate body members pivotally connected at -17t to form an intermediate body portion having two ends. 2, each having a non-flange end and a flange end pivotally attached to one end of the intermediate body portion.
and coupling means for coupling the flanged ends to each other.

A clamp device for an instrumentation port according to an embodiment of the present invention includes two end body members each having a first end and a second end, a link connecting means for linking the first end, and a link connecting means for linking the first end, and a link connecting means for linking the first end to the second end. and coupling means for releasably coupling,
The spacing between the second ends is adjustable when the coupling means is released.

Another embodiment of the invention provides a clamping device for sealing an interface between two substantially tubular objects.

In this clamping device, each of the tubular bodies has a clamp receiving portion, and at least one substantially annular clamping device engages the clamp receiving portion. The clamp device includes two end body members each having a first end and a second end, and a link connecting means for linking the first ends such that a distance between the second ends can be adjusted. and coupling means for coupling the second end.

DETAILED DESCRIPTION Referring to FIGS. 3 and 4, one embodiment of the clamping device of the present invention is shown in plan and cross-sectional views, respectively. The clamping device, designated generally by the numeral 30, is comprised of two end body members 31. Each end body member 31 has a first end or non-flange end 310 and a second end or flange end 31F. 1, in the assembled condition, these flanged ends are held together by cap screws (retaining means) 35. In a preferred embodiment, one of the flanged ends 31F has an unthreaded cap screw hole, and the other flanged end 31F has an unthreaded cap screw hole.
1F has a threaded hole for a presser screw. The non-flange end 3111 of the end body member 31 is the flange end 3
They are connected in a W3 manner so that the radial spacing between the 1Fs can be adjusted. Thus, the present invention provides an integral clamping device with an adjustable end adapted to open in a jaw-like manner.During the assembly operation, this jaw-like structure is Allow the assembled clamping device, except that it has not yet been inserted, to change to the open position.

The clamping device in the open position is easily placed in position over the flanges 10 and 11.

In one embodiment of the invention, the linking means for linking both end body members so that the spacing between the flanged ends of the clamping device is adjustable includes an intermediate body member. Means such as link plates 33 are provided to pivotally connect the intermediate body members 32 to each other and to the unflangeed ends 31U of the end body members 31. Each end of the intermediate body member 32 and the non-flange end 3 of the end body member 31
10 and extending bosses 34, each boss 34 extending into a hole in the link plate 33 with a known BJ'A. In the preferred embodiment, each boss 34 has a retaining means, such as a split bottle, for retaining the link plate thereon. As shown in FIG. 4, the main body members are preferably connected by a pair of link plates 33.

As will be readily apparent to those skilled in the art, means other than those detailed above may be used to link the non-flange ends of the end body members.

For example, in some cases it may be preferable to provide more than one intermediate body member, and in other cases, the arcuate span of the end body members may be widened and the non-flangeed ends 31U interconnected by link plates. It may be desirable to link directly to

The operation of the clamping device according to the invention may be advantageously explained by discussing the use of the clamping device of FIGS. 3 and 4 in conjunction with the instrumentation boat interface shown in FIG. Dew.

Due in part to the articulated structure of the clamping device of the present invention, the clamping device may be assembled with little effort around the instrumentation boat interface shown in FIG. Once removed from the device 30, the flanged end 31F of the clamp device easily separates in a jaw-like manner. In particular, by providing at least two mutually pivotally connected end body members 31, the flanged end 31F can easily pass a sufficient distance around the flanges 10 and 11 for the clamping device 7)O to pass around the flanges 10 and 11. classify each other. These flanged ends 31F are then easily reconnected by the cap screws 35.

As shown in FIGS. 3 and 4, a clamping device 30 according to an embodiment of the present invention is substantially ring-shaped when in an assembled configuration;
The inner portion or surface of 0 is adapted to engage the outer portions or surfaces of flanges 10 and 11.

As mentioned above, it is desirable for the clamping device of the present invention to apply adequate seating forces to the flange interface.

As best shown in FIGS. 1 and 4, the application of such a seating force causes the inwardly facing portions of the clamping device 30 to be substantially non-perpendicular with respect to the axes 38 of the flanges 10 and 11. In the assembled configuration, achieved by providing flat surfaces 36 and 37, surfaces 36 and 37 of clamping device 30 respectively
and 11 are substantially parallel with respect to surfaces 39 and 40. When the clamp device 30 is assembled, the inner diameter of the clamp device T130 is such that the retaining screw 35 is at the flange end 31F.
Try to get smaller until you pull them together.

Due to the reduced inner diameter of the clamping device 30, the surface 36 is similar to the surface 3.
9 and surface 37 engages surface 40, resulting in opposing axial pressures being applied to flanges 10 and 11. To apply the most precise axial pressure,
The inwardly facing portion of the clamping device 30 is machined;
Cast or forged surfaces 39 of flanges 11 and 10
and 40, preferably
In particular, surfaces 38.37 and 39. of clamping device 30.
40 is controlled so that appropriate axial pressure is exerted when the flanged ends 31F come into contact.

As mentioned above, it is important for instrument boat interface clamping devices of the type disclosed herein to achieve and maintain proper and uniform contact and pressure to the interface. Such contact and pressure will ensure proper seating of gasket 12 and prevent over-compression on gasket 12; It helps maintain a tight seal.

Part of these purposes is the flanged end 31 of the end body member.
This is achieved by forming a reference surface at F. According to the invention, the clamping device 30 is e.g. machined, cast or forged in accordance with methods known in the art so that when the reference surface 310 contacts the flange 1
and 11 to provide proper contact and pressure to the interface between them. By "preloading" the clamping device of the present invention in this manner, the time required to position and assemble the clamping device on the instrument boat interface is reduced and the need for clearance limiting means is reduced. That is, once the clamping device has been placed around the flange in the manner described above, the clamping mechanism will be removed when the cap screw is sufficiently torqued to create a tight contact between the reference surfaces of the flanged ends. Appropriate dimensional relationships of the device are achieved.

This properly seats and compresses the gasket. Applying more torque to the cap screw will not overcompress the gas get, and applying more torque will cause the gasket to remain seated as the pressure in the flange increases, so the clamping device In particular, the clamping device of the present invention is preferred as a means for preloading the flanges of the present invention, which achieves the above-mentioned objects when a torque of no more than about 60 rt/lb (39,6 III/Kg) is applied to the cap screw. In the preferred embodiment, the reference surface is simply the flat surface 310 of the flanged end 31F. However, as will be apparent to those skilled in the art, it is within the scope of the present invention to use reference surfaces of any particular shape or configuration. In some cases, it may be desirable to provide an engaging portion.

Gasket 12 is properly seated by the clamping device of the present invention without the need for the axial loading devices previously used. This advantage is achieved in part by providing body members 31 and 32 with an arcuate span that is substantially smaller than the arcuate span of body portions 13^, 13B and 13C due to the clamping devices heretofore used. It originates from. Preferably, the body member according to the present invention does not span an arc of more than about 90°.The inventors of the present application believe that such a reduction in arcuate span and a reduction in the clamping device inner diameter result in contact between the clamping device 30 and the flange 10.11. I learned that I could expand my reputation. This increased contact area aids in seating the gasket 2 when assembling the clamp device T130. The increased number of body members with reduced arcuate spans also aids in seating the gasket 12 when assembling the clamping device 30.Using the clamping device according to the present invention also eliminates the need for axial loading devices. , thus simplifying the assembly procedure and reducing operator exposure to potentially hazardous conditions.

Referring to FIG. 5, another embodiment of a clamping device according to the present invention is shown in cross-section in conjunction with a typical instrumentation boat interface. In this embodiment, the conduits, tubular bodies or flanges 41,42 co-operate in a telescoping manner to seal the instrumentation port interface therebetween. In the context of the reactor vessel, flange 41 consists of the upper part of flange 10 (FIG. 1);
2 is a cylindrical conduit that supports a thermocouple extending inside the flange 41. As with conventional interfaces, a gasket 12 is provided to ensure a proper seal between flanges 41 and 42. In contrast to the interface shown in FIG. 1, proper seating of the gasket 12 in FIG. 5 requires the application of an axial pressure to each flange directed away from its interface edge. shall be. That is, the clamping device must apply axially upward pressure on the flange or cylindrical conduit 42 with respect to the flange 41. A conventional clamping device used to accomplish this purpose is described in U.S. Patent Application Serial No. 925,861. According to another embodiment of the invention:
This objective is achieved by the positioning clamp device 50 and the model clamp device 60 working together. The clamp devices 50 and 60 may have any planar structure, but the third
Preferably, an articulated structure as shown in the Figures is used; however, as shown in Figure 5, the cross-sectional construction of the clamping device 50.60 and flange 41.42 is similar to that shown in Figures 1 and 4. The cross-sectional structure of the clamping device 30 and the flange 10.11 differs substantially.

In particular, the flange 42 includes an annular groove (clamp receiving portion) 43 on its outer surface for receiving the positioning clamp device 50. At least a portion of flange 51 engages annular groove 43 .

Also, the lower surface 52 of the positioning clamp device 50 is not perpendicular to the central axis 44 of the flange 41.42. In this way, any part of the lower surface 52 and the flange 41.4
The axial distance between the two ends is functionally related to the radial distance of said portion from the central axis 44.

In particular, the distance between the surface or lower surface 52 and the end of the flange 42 decreases as the surface radius decreases, i.e. the radius at a location on the surface.

The upper end of flange 41 has a generally planar surface 45, but this surface 45 is also not substantially perpendicular with respect to central axis 44, and the distance between surface 45 and the border edge of flange 41 also depends on the surface radius. decreases as . As used herein, the term flange end refers to the axially most distant portion of the flange, eg, the end of flange 41 refers to the innermost radius of surface 45.

Surface 45 and lower surface 52 together define a wedge-shaped opening 70 for clamping device 60 .

The inner surface of the clamping device 160 provides engagement means adapted to cooperatively engage the wedge-shaped opening lower 0 . especially,
Clamping device 60 has an upper surface 61 and a lower surface 62, both of which are disposed at non-perpendicular angles with respect to central axis 44. As shown in FIG.
5 and is preferably parallel to surface 45, and upper surface 61 engages lower surface 52 and is preferably parallel to surface 45.
These surfaces 61 and 62, which are preferably parallel to 2, are inclined towards the axial center of the open lower lower 0 as their radial distance from the central axis 44 decreases. Depending in part on the articulated structure of clamping device 60 (see FIG. 3), the inner diameter of clamping device 60 decreases as flanged ends 31F are pulled together. This reduction in the inner diameter of the clamping device fi60 is also due to the relationship between the axial and radial distances of the surfaces described above.
The axially upward pressure on the flange 41 is applied to the flange 4.
Try to give it to 2.

As will be apparent to those skilled in the art, the clamping device shown in FIG. In some applications, a two-piece split ring may be used in place of the locating clamp device 50; in other applications, the locating clamp device 50 may be eliminated altogether and the flange 42 may be configured to have the appropriate profile. It may be desirable to simply form. However, in most situations, especially in nuclear power generation installations, it is impractical to replace or redesign the flange 42, so in such situations it is desirable to provide a ramp such as the clamping device 50. Furthermore, the positioning clamp device 50 and the schematic clamp device 60 may be combined into one clamp, in which case the clamp shall have an inner surface corresponding to the combination of the positioning clamp device 50 and the model clamp device 60. . It will also be appreciated by those skilled in the art that the clamping device shown in FIG.
5.52.61 and 62, but it is sufficient to provide only one of these surfaces to achieve the purpose of the clamping device disclosed herein, e.g. perpendicular to the central axis 44. It is possible to provide surfaces 45, 52 and 61 on the surface 45, 52 and 61 and to keep surface 62 in an inclined shape. By providing one inclined surface in this way, it is possible to assemble the clamping device 60 between the surfaces 5Z and 45, and the flange 4
An axially upward pressure will be exerted on 2.

As has been made clear by the foregoing description, the clamping device and clamping device of the present invention quickly and effectively seal instrumentation boat interfaces, thereby providing a high degree of protection against leakage while maintaining a high degree of protection for nuclear power plants. Reduce worker exposure to hazardous conditions. In particular, the clamping device provided by the present invention can be easily handled by one operator even though it is used for relatively large instrumentation boats. In addition, the clamp device can be quickly applied to the interface between the instrumentation boat and the instrumentation boat because only one presser screw needs to be attached to the interface between the instrumentation boat and the instrumentation boat.

As will be apparent to those skilled in the art, the foregoing has been presented solely for detailed description of the invention. For example, clamping devices have been described for use on tubular conduits associated with instrumentation boat interfaces.

However, the clamping device of the invention is also applicable to other shapes of conduits, such as square, rectangular, triangular, etc. The clamping device of the invention may also be used in other applications, such as for example in transport containers and/or storage containers. It is pointed out that various other changes may be made in shape, size, etc. without departing from the scope and spirit of the invention as set forth in the claims.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view showing a typical instrumentation boat interface, Figure 2
3 is a plan view showing a clamping device according to the prior art, FIG. 3 is a plan view showing a clamping device according to an embodiment of the present invention, and FIG.
The figure is a sectional view taken along the line 4--4 in FIG. 3, and FIG. 5 is a sectional view of another embodiment of the present invention. 10.11.41.42...Flange, conduit or object 30...Clamp device 31...End body member 310...Reference surface 31F...Flanged end or second end 310...
Flangeless end or first end 32... intermediate body member (
Link coupling means) 33... Link plate (intermediate link, end link) 35... Holding screw (holding means) 36.37... Surface (inner surface of main body member) 39.40
...Surface (outer surface of conduit) 50.60...Clamp device 43 of clamp tightening device...Annular groove (clamp receiving part) 70...Opening (clamp receiving part) FIG, l. FIG, 3゜FIG, 4゜

Claims (1)

[Scope of Claims] 1) A clamping device supported on an outer surface of a first substantially tubular conduit and a second substantially tubular conduit and sealing an interface between the first and second conduits. (a) two arcuate intermediate body members and two arcuate end body members, the inner surfaces of each of the intermediate body members and the end body members being connected to the first and second conduits; (b) each of said end body members has a flanged end and a non-flange end; (c) two end links; , each end link pivotally coupling one flangeless end of the end body member to one end of the intermediate body member; (d) pivotally connecting the other end of the intermediate body member; A clamping device comprising intermediate links that are capable of interconnecting, and further comprising: (e) retaining means for releasably retaining at least a portion of said flanged end in intimate contact. 2) a clamping device adapted to be supported by a portion of a first object and a second object and sealing an interface between the first object and the second object, the clamping device comprising: (a) a first end; and second
two ends each having a second end having a reference surface;
(b) retaining means for releasably retaining said reference surfaces in intimate contact; and (c) adjusting the spacing between said second ends when said retaining means is released. linking means for linking said first end as possible. 3) a clamping device for sealing an interface between a first substantially tubular object and a second substantially tubular object axially aligned with the first object, comprising: (a) Said first and second
Each of the objects has a clamp receiving portion, and further includes (b) at least one substantially annular clamping device engaging the clamp receiving portion, the clamping device having a first end and a second end. two end body members, each having a second end having a reference surface, and linking means linking the first end so that the spacing between the second ends is adjustable; and retaining means for releasably holding the reference surfaces in close contact.