CN113405682A

CN113405682A - Pipe inner wall temperature measuring device

Info

Publication number: CN113405682A
Application number: CN202110666477.3A
Authority: CN
Inventors: 许倩; 金向颖
Original assignee: China Institute of Atomic of Energy
Current assignee: China Institute of Atomic of Energy
Priority date: 2021-06-16
Filing date: 2021-06-16
Publication date: 2021-09-17
Anticipated expiration: 2041-06-16
Also published as: CN113405682B

Abstract

A pipe inner wall temperature measuring device comprising: the temperature measuring device comprises a supporting rod, a first sliding part, at least two rotating rods, at least one temperature measuring element and at least two linkage parts. The first sliding member is slidably disposed on the support rod. One end of each of the rotating levers is rotatably connected to the supporting rod. Each temperature measuring element is arranged at one end of the rotating rod, which is far away from the supporting rod. One end of each linkage piece is connected to one rotating rod in a sliding mode, and the other end of each linkage piece is fixedly connected to the first sliding piece; the linkage is configured to: when the first sliding part slides along the supporting rod, the linkage part slides along the rotating rod to drive the rotating rod to rotate relative to the supporting rod. The solution according to the invention is particularly suitable for measuring the temperature of the inner wall of an elongated tube, such as a cladding tube.

Description

Pipe inner wall temperature measuring device

Technical Field

The invention relates to the technical field of pipe wall temperature measurement, in particular to a pipe body inner wall temperature measuring device for a small-size thin pipe.

Background

At present, a temperature sensor or a thermocouple is usually adopted to measure the temperature of the pipe wall on the inner side of the pipe body, the measuring mode is simple and easy to operate, and the temperature sensor or the thermocouple only needs to stretch into the pipe body and be attached to the pipe wall. However, in the case of an elongated tube (for example, a tube with an inner diameter less than 2cm and a depth greater than 10 cm), it is difficult to fix a temperature sensor or a thermocouple on the inner wall of the tube to be measured due to the small inner diameter of the tube, and thus it is difficult to accurately measure the temperature of the inner wall of the elongated tube.

Disclosure of Invention

An embodiment of the present invention provides a pipe inner wall temperature measuring apparatus, including:

a support bar;

the first sliding piece is arranged on the supporting rod in a sliding mode;

at least two rotating rods, one end of each rotating rod being rotatably connected to the supporting rod;

each temperature measuring element is arranged at one end of the rotating rod, which is far away from the supporting rod; and

one end of each linkage piece is connected to one rotating rod in a sliding mode, and the other end of each linkage piece is fixedly connected to the first sliding piece; the linkage is configured to: when the first sliding part slides along the supporting rod, the linkage part slides along the rotating rod to drive the rotating rod to rotate relative to the supporting rod.

Additional aspects and advantages of embodiments of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

Drawings

The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

fig. 1 is a schematic structural view of a temperature measuring device according to an embodiment of the present invention, in which a rotating lever is in a collapsed state;

fig. 2 is a schematic structural view of the temperature measuring device shown in fig. 1, in which a rotating lever is in an open state;

FIG. 3 is a schematic cross-sectional view of the temperature measuring device of FIG. 1;

FIG. 4 is a schematic cross-sectional view of the temperature measuring device of FIG. 2;

FIG. 5 is a schematic view of the temperature measuring device before entering the cladding tube;

FIG. 6 is a schematic view of a structure in which a temperature measuring device measures a temperature inside a cladding pipe; and

fig. 7 is a schematic top view of the first slider.

Description of the main element symbols:

a temperature measuring device 10, a support rod 11, a hand-held portion 111, a first slider 12, a center hole 121, a threading hole 122, a rotating rod 13, a temperature measuring element 14, a wire 141, a linkage member 15, a second slider portion 151, a stopper member 16; cladding tube 20, inner wall 21.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the accompanying drawings are illustrative only for the purpose of explaining the present invention, and are not to be construed as limiting the present invention.

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "upper", "lower", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like, indicate orientations or positional relationships based on those shown in the drawings, and are used merely for convenience in describing the present invention and for simplicity in description, and do not indicate or imply that the referenced devices or elements must have a particular orientation, be constructed in a particular orientation, and be operated, and thus, are not to be construed as limiting the present invention. Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", may explicitly or implicitly include one or more of the described features. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; may be mechanically connected, may be electrically connected or may be in communication with each other; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

The following disclosure provides many different embodiments or examples for implementing different features of the invention. To simplify the disclosure of the present invention, the components and arrangements of specific examples are described below. Of course, they are merely examples and are not intended to limit the present invention. Furthermore, the present invention may repeat reference numerals and/or letters in the various examples, such repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and/or configurations discussed. In addition, the present invention provides examples of various specific processes and materials, but one of ordinary skill in the art may recognize applications of other processes and/or uses of other materials.

Fuel rods for use in reactors typically include a cladding tube and fuel pellets disposed inside the cladding tube. The diameter of the cladding tube is very small, the temperature is high in the operation process, the heat flow density is large, and the internal pressure is high. It is often necessary to test the cladding tube for safety before it is actually used. The diameter of the cladding tube used in the test is 8.0mm, the depth is 500mm, when the cladding safety performance test is carried out, steam flows in the cladding tube, the condition that the cladding tube is oxidized in a high-temperature steam environment needs to be researched in the test, and the temperature of the cladding tube is monitored in real time.

As mentioned in the background section, it is difficult to accurately measure the temperature of the inner wall of an elongated tube (e.g., a tube with an inner diameter of less than 2cm and a depth of more than 10 cm), especially for an elongated tube (e.g., a cladding tube) with an inner diameter of about 1cm and a depth of more than 20 cm. Accordingly, the present invention addresses the above-mentioned deficiencies and, in particular, provides a temperature measuring device that is capable of accurately measuring the temperature of the inside wall of an elongated tube (even an ultra-elongated tube).

Referring to fig. 1 to 4, a temperature measuring device 10 for measuring the temperature of the inner wall of a pipe is provided in an embodiment of the present invention.

The temperature measuring device 10 of the embodiment of the present invention may include: a support bar 11, a first slider 12, two rotating bars 13, two temperature measuring elements 14 and two linkage pieces 15.

The support bar 11 may have a first end (e.g., the upper end in the figure) and a second end (e.g., the lower end in the figure) opposite the first end.

The first slider 12 is slidably disposed on the support bar 11. Specifically, the first slider 12 is slidably provided on the support rod 11 in the axial direction of the support rod 11. That is, the first slider may slide back and forth along the support bar 11 toward the first and second ends of the support bar 11.

In some embodiments, the first sliding member 12 is provided with a central hole 121, the supporting rod 11 is slidably disposed through the central hole 121, and accordingly, the first sliding member 12 is slidably sleeved on the supporting rod 11.

In other embodiments, a sliding groove or a sliding block may be provided on the first sliding member 12, and a sliding block or a sliding groove may be provided on the supporting rod 11, respectively, so that the first sliding member 12 is slidably connected with the supporting rod 11.

One end of each rotating lever 13 is rotatably connected to the support lever 11. That is, each rotating lever 13 is hinged on the support lever 11, and each rotating lever 13 is rotatable with respect to the support lever 11. Specifically, the rotating lever 13 may have a first end (e.g., an end portion located at an upper side in the drawing) and a second end (e.g., an end portion located at a lower side in the drawing) opposite to the first end. A first end of each rotating lever 13 is rotatably connected to the supporting lever 11. The second end of each turning rod 13 is a free end.

Each temperature measuring element 14 is arranged at one end of one of the swivelling levers 13 remote from the bearing lever 11. I.e. each temperature measuring element 14 is arranged at the second or free end of the swivelling lever 13.

Each linkage member 15 has one end slidably connected to one of the rotation levers 13 and the other end fixedly connected to the first slide member 12. The linkage member 15 may have a first end (e.g., the upper end in the figure) and a second end (e.g., the lower end in the figure) opposite the first end. A first end of the linkage member 15 is slidably connected to one rotating rod 13, or a first end of the linkage member 15 is slidably connected to one rotating rod 13; the second end of the link member 15 is fixedly connected to the first slider 12. As will be readily understood by those skilled in the art, the second end of the link 15 is slidably connected to the rotating rod 13 between the first and second ends of the rotating rod 13.

Wherein the linkage 15 is configured to: when the first sliding member 12 slides along the support rod 11, the link member 15 slides along the rotating rod 13 to rotate the rotating rod 13 relative to the support rod 11.

In such an embodiment, the first slider 12 converts a translational movement along the support bar 11 into a rotational movement of the swivelling bar 13 relative to the support bar 11. By moving the first slider 12 up and down, the link 15 slides freely with respect to the rotating lever 13, thereby controlling the opening and closing of the rotating lever 13.

The rotating lever 13 may have a folded state and an unfolded state according to an angle of the rotating lever 13 with respect to the supporting lever 11.

Specifically, when the first sliding member 12 is driven to slide along the supporting rod 11 towards the second end of the supporting rod 11, the linkage member 15 moves downward along with the first sliding member 12, so that the first end of the linkage member 15 drives the free end of the rotating rod 13 to move downward, so that the included angle between the rotating rod 13 and the supporting rod 11 is gradually reduced, and the rotating rod 13 is in the folded state, as shown in fig. 1 and 3.

When the first sliding member 12 is driven to slide along the supporting rod 11 towards the first end of the supporting rod 11, the linkage member 15 moves upwards along with the first sliding member 12, so that the first end of the linkage member 15 drives the free end of the rotating rod 13 to move upwards, so that the included angle between the rotating rod 13 and the supporting rod 11 is gradually increased, and the rotating rod 13 is in an open state, as shown in fig. 2 and 4.

In use, the rotating rod 13 is in a folded state by sliding the first sliding part 12 (see fig. 5), then the front end of the temperature measuring device 10 is inserted into the cladding tube 20, and then the first sliding part 12 is slid upwards to gradually open the rotating rod 13, when the radial dimension of the rotating rod 13 (i.e. the projection length of the rotating rod 13 in the radial direction) is equal to or slightly greater than the inner radius of the cladding tube 20, the free end of the rotating rod 13 abuts against the inner wall 21 of the cladding tube 20, and the temperature measuring element 14 abuts against the inner wall 21 of the cladding tube 20 (see fig. 6). Thus, the temperature measuring element 14 can be used to accurately measure the temperature of the inner wall 21 of the cladding tube 20.

In the above embodiment, the second end of the linkage 15 is fixedly connected to the first slider 12, rather than being hinged or rotationally connected to the first slider 12. When measuring the temperature of the inner wall 21 of the cladding tube 20, a portion of the first slide 12 may protrude into the cladding tube 20 (as shown in fig. 6), and therefore the first slide 12 cannot be dimensioned too large, slightly smaller than the inner diameter of the cladding tube 20. As will be described later, the first slider 12 is provided with a central hole 121 and a threading hole 122 for threading a wire 141 of the temperature measuring element 14. To prevent the wire 141 of the temperature sensing element 14 from buckling, the central hole 121, the wire passing hole 122, and the second end of the linkage member 15 are preferably substantially collinear. Referring to fig. 7, the second end of linkage 15 is preferably located on the center line a of central bore 121 and threading bore 122. That is, the center or edge of the second end of the linkage 15 is on the center connection line a; alternatively, the projection of the link 15 on a horizontal plane passing through the center line a intersects the center line a.

Thus, when the rotating lever 13 is folded, the wire 141 can smoothly enter the threading hole 122 without being bent or jammed. In such a case, the first slider 12 does not have enough space to arrange the hinge portion hinged to the link 15. Also, even if the position of the link 15 on the first slider 12 is not limited as described above, i.e., does not need to intersect the center connecting line a, it is difficult for the current process to weld the hinge portion at the axial surfaces of the first slider 12 and the link 15 because the sizes of the first slider 12 and the link 15 are too small.

The inventor of the present invention particularly fixedly connects the second end of the link 15 to the first sliding member 12, and the first end of the link 15 slides along the rotating rod 13 to drive the rotating rod 13 to rotate relative to the supporting rod 11, so that the rotating rod 13 can be opened and closed, and the diameter of the first sliding member 12 can be designed to be small, thereby meeting the detection requirement of the cladding tube 20.

It will be readily understood by those skilled in the art that in the present embodiment, the number of the rotating levers 13 and the linkage members 15 is the same, i.e., each rotating lever 13 is slidably connected with one linkage member 15.

In the above embodiment, the number of the rotating levers 13, the interlocking member 15, and the temperature measuring element 14 is two. In other embodiments, the number of turning levers 13 and linkages 15 may also be three, four, five or even more. In other embodiments, the number of temperature measuring elements 14 can be the same as the number of rotating rods 13, or can be less than the number of rotating rods 13. For example, in some embodiments, the temperature measuring device 10 may be provided with only one temperature measuring element 14, the one temperature measuring element 14 being provided at the free end of either rotating lever 13. In some embodiments, the number of the temperature measuring elements 14 is the same as that of the rotating rods 13, and one temperature measuring element 14 is arranged at one end of each rotating rod 13 far away from the supporting rod 11.

In some embodiments, the linkage 15 is further configured to: when the first sliding member 12 slides along the support rod 11, the link member 15 is elastically deformed so that one end thereof slides along the corresponding rotating rod 13 and the other end thereof remains fixed. In other words, by the elastic deformation of the link member 15, a slight rotation of the first end of the link member 15 relative to the second end thereof is achieved, thereby simultaneously ensuring that the second end of the link member 15 is fixed to the first sliding member 12 and the first end of the link member 15 slides along the rotating lever 13.

In some embodiments, the linkage 15 may have an arcuate shape. Thereby, can enough make linkage 15 be convenient for take place elastic deformation, can also strengthen linkage 15's mechanical strength simultaneously to can not reset after deformation takes place, thereby can not drive dwang 13 upwards to rotate in order to be in the open mode.

In some embodiments, the arcuate opening of the linkage 15 faces away from the support bar 11. I.e. the two linkage pieces 15 are arranged facing away from each other. So that when the first sliding member 12 slides towards the first end of the supporting rod 11, the sliding of the first end of the link member 15 along the rotating rod 13 towards the first end thereof is facilitated; when the first sliding member 12 slides towards the second end of the supporting rod 11, it is more favorable for the first end of the link member 15 to slide towards the second end along the rotating rod 13; thereby making the process of folding and unfolding the rotating lever 13 smoother.

Further, in some embodiments, the arc of the linkage 15 may be set between 10-30 degrees. That is, when the rotating lever 13 is in the collapsed state, the arc of the link 15 is maximum and does not exceed 30 degrees. When the rotating lever 13 is in the open state, the arc degree of the rotating lever 13 is preferably not less than 5 degrees, and further not less than 10 degrees, so that the rotating lever 13 has appropriate elastic deformation and mechanical strength.

The cross section of the linkage piece 15 can be circular, oval or polygonal (the number of sides is more than or equal to 3). In some embodiments, the linkage 15 may be square or rectangular in cross-section.

In some embodiments, the linkage 15 is a wire. The diameter of the wire may be 5mm or less. Further, the diameter of the wire is 3mm or less. For example, 1mm, 2mm, 2.5mm, etc.

In some embodiments, the cross-section of the linkage 15 may further preferably be an elongated square, and the rectangular shape may have an aspect ratio of 10: 1 to 3: 1. in these embodiments, the linkage 15 is a metal sheet (or strip or band). It will be readily appreciated that one of the wider side surfaces of the sheet faces the support bar 11 and the other faces the temperature sensing element 14. Compared with a metal wire, the metal sheet has better mechanical strength while being capable of generating elastic deformation.

In some embodiments, the thickness of the metal sheet may be less than or equal to 3mm in order to facilitate elastic deformation. The metal wire or the metal sheet can be made of stainless steel.

In some embodiments, a second slider 151 is fixed to one end of the link 15, and the second slider 151 is slidably disposed on the rotating rod 13. The second sliding member 151 may be a ring-shaped member, which is slidably fitted over the rotating rod 13. The shape of the ring-shaped member may be circular, elliptical, polygonal, or irregular.

In some embodiments, the two rotating rods 13 are evenly distributed along the axial direction of the support rod 11. I.e. the two swivelling levers 13 are axially symmetrical with respect to the supporting rod 11. When the number of the rotating rods 13 is three or more, these rotating rods 13 are uniformly distributed in the axial direction of the support rod 11.

The temperature measuring element 14 can be fixedly arranged at the second or free end of the swivelling lever 13. In some embodiments, the temperature sensing element 14 can be welded to the free end of the rotating rod 13.

In some embodiments, the temperature sensing element 14 is a thermocouple. The rotating rod 13 and the thermocouple are tightly coupled together. In other embodiments, the temperature sensing element 14 is a temperature sensor.

The first sliding member 12 is further provided with a threading hole 122 for threading a wire of the temperature measuring element 14.

The first slide 12 has a diameter smaller than the inner diameter of the pipe to be measured. The diameter of the first slide 12 may be, for example, 5cm or less. Further, the diameter of the first slide member 12 is 2cm or less.

The temperature measuring device 10 further includes: the holding portion 111 is fixedly disposed at an end of the support rod 11 away from the rotation rod 13. Referring to fig. 3 and 4, the diameter of the hand-held portion 111 is larger than that of the support rod 11, and a portion of the hand-held portion 111 may extend into the central hole 121 of the first slider 12. The diameter of the hand grip 111 may be slightly smaller than the inner diameter of the central hole 121 so that the hand grip 111 may slide inside the central hole 121 while ensuring stability of the support rod 11 during sliding.

The temperature measurement device 10 may further include: and a stopper 16 provided on the hand-held portion 111 for stopping the first slider 12 from sliding toward the hand-held portion 111. In some embodiments, the stop 16 is a compression nut and the hand piece 111 is provided with a thread that mates with the compression nut. In other embodiments, the stop 16 may be other conventional locking structures.

The method of using the temperature measuring device 10 according to the embodiment of the present invention will be described with reference to fig. 5 and 6. Before use, the rotating rod 13 is in a folded state by sliding the first sliding member 12 downwards (see fig. 5), then the front end of the temperature measuring device 10 is inserted into the cladding tube 20, and after reaching a designated position, the first sliding member 12 is slid upwards to gradually open the rotating rod 13, when the radial dimension of the rotating rod 13 (i.e. the projection length of the rotating rod 13 in the radial direction) is equal to or slightly greater than the inner radius of the cladding tube 20, the free end of the rotating rod 13 abuts against the inner wall 21 of the cladding tube 20, and the thermocouple is tightly pressed against the inner wall 21 of the cladding tube 20 (see fig. 6), and the first sliding member 12 is fixed by screwing the pressing nut upwards. At this time, since the free end of the rotating rod 13 abuts against the inner wall 21 of the cladding tube 20, the temperature measuring device 10 is relatively fixed to the cladding tube 20, so that the inner wall of the cladding tube 20 can be measured by the thermocouple.

It can be seen that the present invention provides a temperature measuring device 10 that can be opened and closed, which can not only tightly attach a thermocouple to the inner wall 21 of the cladding tube 20 to accurately measure the temperature of the inner wall 21 of the cladding tube 20; but also freely inside the tube body, in order to measure the inner wall 21 of the cladding tube 20 at different depths. The temperature measuring device 10 provided by the embodiment of the invention has the advantages of simple structure, extremely small size and convenience in operation, solves the key technical core problem of temperature measurement in an experiment, and ensures the smooth implementation of the experiment.

Although the embodiment of the present invention specifically uses the example of measuring the temperature of the cladding tube 20 to describe the method of using the temperature measuring device of the present invention in detail, it is easily understood by those skilled in the art that the temperature measuring device of the present invention is suitable for measuring the temperature of all tube bodies with different diameters; the device is particularly suitable for measuring the temperature of a thin pipe with the diameter less than 2cm (particularly the thin pipe with the diameter less than 1 cm) or an elongated pipe.

In the description herein, references to the terms "one embodiment," "certain embodiments," "illustrative embodiments," "an example," "specific example," or "some examples" or the like mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

While embodiments of the present invention have been shown and described, it will be understood by those of ordinary skill in the art that: various changes, modifications, substitutions and alterations can be made to the embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A pipe inner wall temperature measuring device, comprising:

a support bar (11);

a first slider (12) slidably arranged on the support bar (11);

at least two rotating rods (13), one end of each rotating rod (13) is rotatably connected to the supporting rod (11);

at least one temperature measuring element (14), wherein each temperature measuring element (14) is arranged at one end of one rotating rod (13) far away from the supporting rod (11); and

at least two linkage pieces (15), wherein one end of each linkage piece (15) is connected to one rotating rod (13) in a sliding mode, and the other end of each linkage piece (15) is fixedly connected to the first sliding piece (12); the linkage (15) is configured to: when the first sliding part (12) slides along the supporting rod (11), the linkage part (15) slides along the rotating rod (13) to drive the rotating rod (13) to rotate relative to the supporting rod (11).

2. The apparatus of claim 1,

the linkage (15) is further configured to: when the first sliding part (12) slides along the supporting rod (11), the linkage part (15) is elastically deformed, so that one end of the linkage part slides along the corresponding rotating rod (13) and the other end of the linkage part is kept fixed.

3. The apparatus of claim 2,

the linkage piece (15) has an arc shape.

4. The apparatus of claim 3,

the arc-shaped opening of the linkage piece (15) faces away from the support rod (11).

5. The apparatus of claim 3,

the arc of the linkage piece (15) is between 10 and 30 degrees.

6. The device according to any one of claims 1 to 5,

the linkage piece (15) is a metal wire.

7. The device according to any one of claims 1 to 5,

the linkage piece (15) is a metal sheet.

8. The apparatus of claim 1,

and a second sliding part (151) is fixed at one end of the linkage part (15), and the second sliding part (151) is arranged on the rotating rod (13) in a sliding manner.

9. The apparatus of claim 8,

the second sliding part (151) is an annular part which can be sleeved on the rotating rod (13) in a sliding manner.

10. The apparatus of claim 1,

the at least two rotating rods (13) are uniformly distributed along the axial direction of the supporting rod (11).

11. The apparatus of claim 1,

the quantity of temperature elements (14) with the quantity of dwang (13) is the same, every dwang (13) is kept away from the one end of bracing piece (11) all is provided with one temperature elements (14).

12. The apparatus of claim 1,

one end of each of the rotating levers (13) is rotatably connected to the supporting lever (11).

13. The apparatus of claim 1,

the temperature measuring element (14) is welded at one end of the rotating rod (13).

14. The apparatus of claim 1,

the first sliding part (12) is provided with a central hole (121), and the supporting rod (11) is slidably arranged in the central hole (121) in a penetrating mode.

15. The apparatus of claim 1,

the first sliding part (12) is also provided with a threading hole (122) for threading a conducting wire of the temperature measuring element (14).

16. The apparatus of claim 1,

the temperature measuring element (14) is a thermocouple.

17. The apparatus of claim 1, further comprising:

and the handheld part (111) is fixedly arranged at one end, far away from the rotating rod (13), of the supporting rod (11).

18. The apparatus of claim 17, further comprising:

a stopper (16) provided on the hand-held portion (111) for stopping the first slider (12) from sliding toward the hand-held portion (111).

19. The apparatus of claim 18,

the stop piece (16) is a compression nut, and a thread matched with the compression nut is arranged on the handheld portion (111).

20. The apparatus of claim 1,

the tube body is a cladding tube.