JP2013086150A - Jig for positioning and method for positioning member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten time required to complete welding when welding first and second members.SOLUTION: The jig 1 for positioning is used to carry out the positioning of the first and second members that are welded later. The jig 1 for positioning includes an abutting part 4 for positioning the first and second members by abutting on the first and second members and is formed of a combustible material or ceramics.

Description

  The present invention relates to a positioning jig and a member positioning method.

  As shown in Patent Document 1, a header for collecting steam or water flowing in a plurality of heat transfer tubes is installed inside a boiler used in a thermal power plant or the like. This header is composed of a header for collecting steam or water therein, and a stub tube for connecting the header and the heat transfer tube. These headers and stub tubes are fixed by welding.

Japanese Patent Laid-Open No. 3-185431

  A number of stub tubes are connected to the header. For this reason, when manufacturing a header, generally, after temporarily attaching a stub tube to a header and assembling the entire header, each stub tube is finally welded to the header.

  By the way, in recent years, the heat resistance and pressure resistance performance required for the boiler is higher, and it may be necessary to join the header and the stub tube by complete penetration welding. In such a case, it is necessary to perform welding in a state where the header and the stub tube are separated from each other by a predetermined size. Moreover, since the setting of the width of the gap between the header and the stub pipe affects the welding quality, high accuracy is required. For this reason, when complete penetration welding is performed, when temporarily attaching the header and stub pipe, welding the metal fitting that supports the header and the stub pipe apart, and removing the metal fitting after temporary attachment Is used. However, the attachment part of the metal fitting shrinks by welding at the time of temporary attachment, and since the metal fitting is welded to the header and the stub pipe, it takes a lot of time to remove the metal fitting and the header and the stub pipe. There is a problem that the time until welding is completed is prolonged.

  Such a problem does not occur only when the header and the stub tube are completely penetrated and welded. When other metal members are completely penetrated and welded, nonmetal members are completely penetrated. It also occurs when welding.

The present invention has been made in view of the above-described problems, and an object of the present invention is to shorten the time required to complete the welding when welding the first member and the second member.
In particular, an object of the present invention is to shorten the time for welding the header and the stub pipe in the construction of the boiler, and to shorten the time for manufacturing the header.

  The present invention adopts the following configuration as means for solving the above-described problems.

A first invention is a positioning jig for positioning a first member and a second member to be welded later, and is in contact with the first member and the second member. A configuration is adopted in which a contact portion for positioning the member and the second member is provided and formed from a plant material that can be incinerated.

The second invention employs a configuration in which the first invention is made of only wood.

  A third invention is the above described first or second invention, wherein the first member is a header installed in the boiler, and the second member is a stub tube connected to the header. A first protrusion inserted into a stub tube mounting hole provided in the header, a second protrusion inserted into the hole of the stub tube, and an end of the stub tube abutting on the surface and on the back surface A structure is provided that includes a plate portion against which the header is brought into contact.

  4th invention is the member positioning method which positions the 1st member and 2nd member which are welded later, Comprising: The positioning jig which is any one of said 1st-3rd invention is interposed. Temporarily attaching the first member and the second member by separating the first member and the second member, and welding the first member and the second member only after the member arranging step. And a positioning jig removing step for removing the positioning jig after the tacking process.

According to the present invention, the positioning jig is formed from a combustible material or ceramics. The positioning jig formed from the combustible material can be easily removed by incineration with a burner or the like. For this reason, after temporarily attaching the first member and the second member, the positioning jig can be easily removed. Therefore, according to the present invention, the positioning jig can be removed in a short time as compared with the case where the first member and the second member are positioned as a positioning jig as in the prior art, It becomes possible to shorten the time required to complete the welding of the first member and the second member.
Further, by using the positioning jig of the present invention when welding the header and the stub pipe, the time for welding the header and the stub pipe can be shortened, and the time for manufacturing the header can be shortened. it can.

It is a perspective view of the header manufactured using the wooden piece which concerns on one Embodiment of this invention. BRIEF DESCRIPTION OF THE DRAWINGS It is a general view of the wooden piece concerning one Embodiment of this invention, (a) is a longitudinal cross-sectional view, (b) is a bottom view, (c) is a top view. It is a flowchart for demonstrating the manufacturing method of the header using the wooden piece which concerns on one Embodiment of this invention. It is a schematic diagram for demonstrating the manufacturing method of the header using the wooden piece which concerns on one Embodiment of this invention, (a) shows a member arrangement | positioning process, (b) shows a temporary attachment process, (c) Shows the wood piece removal process.

  Hereinafter, an embodiment of a positioning jig and a member positioning method according to the present invention will be described with reference to the drawings. In the following drawings, the scale of each member is appropriately changed in order to make each member a recognizable size. In the following embodiments, the positioning jig of the present invention is a wooden piece, and a case where a header composed of a header and a stub pipe is manufactured using the wooden piece will be described as an example.

FIG. 1 is a perspective view of a header 10 manufactured using the wooden piece 1 (see FIG. 2) of the present embodiment. In FIG. 1, illustration of some stub tubes 12 among the plurality is omitted.
The header 10 is installed inside a boiler provided in a thermal power plant or the like, and includes a header 11 (first member) and a stub tube 12 (second member) as shown in FIG. .

  The header 11 is a substantially cylindrical member whose inside is hollow, and is set so that its central axis is horizontal. A stub tube attachment hole 11b that penetrates the peripheral wall portion 11a is provided in the peripheral wall portion 11a of the header 11. The stub tube mounting holes 11b are provided as many as the stub tubes 12 connected to the header 11, and are gathered at the upper portion of the header 11, as shown in FIG.

  The stub tube 12 is a tube member that connects a heat transfer tube (not shown) and the header 11. The heat transfer tube is a tube member that transfers the amount of heat generated by passing water inside and burning coal or the like to water. The stub tubes 12 are provided in the number corresponding to the number of heat transfer tubes, and are welded to the header 11 so that the internal holes 12a are connected to the stub tube mounting holes 11b of the header 11. In the present embodiment, the header 11 and the stub tube 12 are joined by complete penetration welding. Further, the diameter of the hole 12 a of the stub tube 12 is set to be substantially the same as that of the stub tube mounting hole 11 b of the header 11.

  Next, the wooden piece 1 of this embodiment will be described with reference to FIG. FIG. 2 is an overall view of the wooden piece 1, in which (a) is a longitudinal sectional view, (b) is a bottom view, and (c) is a top view. In order to facilitate understanding of the description, in FIG. 2, a part of the header 11 and the stub tube 12 is indicated by a virtual line. As shown in these drawings, the wooden piece 1 of this embodiment includes a first protrusion 2, a second protrusion 3, and a plate part 4 (contact part). In the following description, the first protrusion 2 side is on the bottom and the second protrusion 3 side is on the top.

The 1st projection part 2 is a site | part inserted in the stub pipe attachment hole 11b of the header 11, and protrudes toward the downward direction. In addition, as shown to Fig.2 (a), the 1st projection part 2 and the 2nd projection part 3 are integrated vertically.
The first protrusion 2 is set in a rectangular parallelepiped shape. Moreover, the shape of the 1st projection part 2 seen from the downward direction becomes a rectangular shape which can be included in the stub pipe attachment hole 11b. As shown in FIG. 2 (b), when the first protrusion 2 is inserted into the stub tube mounting hole 11b, the first protrusion 2 is rectangular when viewed from below. A large space Sa is formed between the long side of the one protrusion 2 and the inner wall of the stub tube mounting hole 11b.
Further, the size of the first protrusion 2 viewed from below is such that when the first protrusion 2 is inserted into the stub tube mounting hole 11b, the first protrusion 2 is located between the first protrusion 2 and the inner wall of the stub tube mounting hole 11b. It is set so that a slight gap is formed. Thereby, the position of the wooden piece 1 with respect to the header 11 can be slightly adjusted.

The 2nd protrusion part 3 is a site | part inserted in the hole 12a of the stub pipe | tube 12, and protrudes upwards.
The second projecting portion 3 is set in a rectangular parallelepiped shape having the same size as the first projecting portion 2. That is, the shape of the 2nd projection part 3 seen from the top is a rectangular shape. As shown in FIG. 2 (c), when the second protrusion 3 is inserted into the hole 12a of the stub tube 12 by the rectangular shape of the second protrusion 3 seen from above, A size space Sb is formed between the long side of the second protrusion 3 and the inner wall of the hole 12a of the stub tube 12.
The size of the second protrusion 3 as viewed from above is such that when the second protrusion 3 is inserted into the hole 12a of the stub tube 12, the second protrusion 3 and the inner wall of the hole 12a of the stub tube 12 It is set so that a slight gap is formed between the two. Thereby, the position of the stub tube 12 with respect to the wooden piece 1 can be slightly adjusted.

The plate portion 4 is a plate member that is integrated with the first protrusion portion 2 and the second protrusion portion 3 and that protrudes to the side of the first protrusion portion 2 and the second protrusion portion 3. The plate portion 4 is a portion where the end portion of the stub tube 12 comes into contact with the upper surface 4a (front surface) and the header 11 comes into contact with the lower surface 4b (back surface). As shown in FIG. 2A, the plate portion 4 is provided at two symmetrical positions with the first protrusion 2 and the second protrusion 3 as the center.
The thickness D of the plate portion 4 defines the distance between the header 11 and the stub tube 12. In the present embodiment, since the header 11 and the stub tube 12 are joined by complete penetration welding, the thickness D of the plate portion 4 is about 2 to 3 mm suitable for complete penetration welding. The length L of the plate portion 4 is set so that the plate portion 4 exceeds the outer wall surface of the stub tube 12 as shown in FIGS. 2 (b) and 2 (c).

As described above, the wooden piece 1 of the present embodiment is formed by integrating the first protruding portion 2, the second protruding portion 3, and the plate portion 4. The wooden piece 1 of the present embodiment is formed only of wood that is a combustible material, and specifically, is formed by compression molding only a cherry tree without using a chemical product such as an adhesive.
It is also conceivable to form the wooden piece 1 by compression molding a tree other than the cherry tree. However, since the wooden piece 1 needs to support the weight of the stub tube 12 and the gap dimension between the header 11 and the stub tube 12 needs to be set with high accuracy, it has a high hardness so as not to be easily deformed. It is preferable to have. On the other hand, considering the manufacturing cost, it is preferable that the forming material is easily processed and the price of the forming material is low. In order to satisfy such conditions, it is preferable to use a cherry tree.

  Next, a method for manufacturing the header 10 using the wooden piece 1 of this embodiment will be described with reference to FIGS. FIG. 3 is a flowchart showing a method for manufacturing the header 10. FIG. 4 is a cross-sectional view schematically showing a method for manufacturing the header 10.

  As shown in FIG. 3, in the method for manufacturing the header 10, the member placement process (step S <b> 1), the tacking process (step S <b> 2), the wooden piece removal process (step S <b> 3), and the main welding process (step S <b> 4) Repeat in order. In the present embodiment, the member positioning method according to the present invention includes a member arranging step (step S1), a tacking step (step S2), and a wood piece removing step (step S3). The positioning jig removing step of the present invention corresponds to the wood piece removing step (step S3) of the present embodiment.

The member arranging step (step S1) is a step of arranging the header 11 and the stub tube 12 with the wooden piece 1 interposed therebetween.
In this member arrangement step, first, the first protrusion 2 of the wooden piece 1 is inserted into the stub tube mounting hole 11b of the header 11. At this time, the two plates 4 of the wooden piece 1 are installed so as to be arranged in a direction along the central axis of the header 11. And the stub pipe | tube 12 by which the edge part was grooved is arrange | positioned so that the 2nd projection part 3 of the wooden piece 1 may be inserted in the hole 12a. As a result, as shown in FIG. 4A, the stub tube 12 contacts the upper surface 4 a of the plate portion 4, the header 11 contacts the lower surface 4 b of the plate portion 4, and the thickness D of the plate portion 4 is the same. The header 11 and the stub tube 12 are arranged in a separated state.

A temporary attachment process (step S2) is a process of temporary attaching by welding only the header 11 and the stub tube 12 after a member arrangement | positioning process (step S1).
In this tacking step (step S2), welding is performed at a location that matches the space Sa that exists on the side of the first protrusion 2 of the wooden piece and the space Sb that exists on the side of the second protrusion 3. By doing so, the header 11 and the stub tube 12 are temporarily attached as shown in FIG. Here, the space Sa is a region where the distance from the wooden piece 1 to the inner wall of the stub tube mounting hole 11b is long, and the space Sb is a region where the distance from the wooden piece 1 to the inner wall of the hole 12a of the stub tube 12 is long. For this reason, it can prevent that a droplet adheres to the wooden piece 1 at the time of welding by performing welding according to these spaces Sa and Sb.

The wooden piece removing step (step S3) is a step of removing the wooden piece 1 after the tacking step (step S2).
In this wooden piece removal step (step S3), the wooden piece 1 is incinerated using a burner (not shown). Since the wooden piece 1 is formed of wood which is a combustible material as described above, it can be easily burned by the flame of a burner. By incinerating the wooden piece 1 in this way, the wooden piece 1 is removed and the positioning of the header 11 and the stub pipe 12 is completed as shown in FIG.

  In addition, the above-mentioned member arrangement | positioning process (step S1), a temporary attachment process (step S2), and a wooden piece removal process (step S3) are performed with respect to each stub pipe | tube 12. That is, all the stub pipes 12 are positioned with respect to the header 11 through the above-described member arranging step (step S1), the tacking step (step S2), and the wooden piece removing step (step S3). Then, after all the stub pipes 12 are positioned with respect to the header 11, the main welding process (step S4) is performed.

The main welding process (step S4) is a process in which complete penetration welding is performed so that the gap between the header 11 and the stub pipe 12 is filled with beads.
In the main welding step (step S4), the header 11 and the stub pipe 12 are welded by MAG welding. However, the present invention is not limited to MAG welding, and a configuration in which gas welding or other arc welding is performed may be employed.

Next, the effects of the wood piece 1 of this embodiment and the positioning method of the header 11 and the stub pipe 12 using the wood piece 1 will be described.
The wooden piece 1 of this embodiment is formed of wood that is a combustible material. The wooden piece 1 made of wood can be easily removed by incineration with a burner. For this reason, after temporarily attaching the header 11 and the stub tube 12, the wooden piece 1 can be easily removed. Therefore, according to the wooden piece 1 of this embodiment and the positioning method of the header 11 and the stub pipe 12 using the wooden piece 1, compared with the conventional case where the metal fitting is used as a positioning jig, it is shorter. The positioning jig can be removed in time, and the time until the welding of the header 11 and the stub tube 12 is completed can be shortened. Therefore, the header 10 can be manufactured in a short time.

  Moreover, the wooden piece 1 of this embodiment is formed only from the timber. A chemical product such as an adhesive gasifies when burned and adheres to the header 11 or the stub tube 12, thereby causing a deterioration in welding quality. On the other hand, when incinerating the wooden piece 1 of this embodiment, no chemical product such as an adhesive is used, so that no gas that causes a deterioration in welding quality is generated. Therefore, according to the wooden piece 1 of the present embodiment, high welding quality can be maintained.

  Further, the wooden piece 1 of the present embodiment includes a first protrusion 2 that is inserted into a stub pipe attachment hole 11b provided in the header 11, a second protrusion 3 that is inserted into a hole 12a of the stub pipe 12, and an upper surface 4a. And a plate portion 4 with which the end of the stub tube 12 abuts and the header 11 abuts against the lower surface 4b. For this reason, the first protrusion 2 and the second protrusion 3 can prevent the header 11 and the stub tube 12 from moving horizontally, and the header 11 and the stub tube 12 are displaced in the horizontal direction. This can be prevented.

  As mentioned above, although preferred embodiment of this invention was described referring an accompanying drawing, it cannot be overemphasized that this invention is not limited to the said embodiment. Various shapes, combinations, and the like of the constituent members shown in the above-described embodiments are examples, and various modifications can be made based on design requirements and the like without departing from the spirit of the present invention.

  For example, in the above-described embodiment, the configuration in which the positioning jig of the present invention is the wooden piece 1 made of wood has been described. However, the present invention is not limited to this, and a positioning jig made of ceramics can also be used. Ceramics can be easily broken by applying an impact with a hammer or the like. Therefore, when a positioning jig formed of ceramics is employed, the positioning jig can be easily removed by hitting and destroying it with a hammer or the like. Even when the positioning jig is formed of ceramics, the same shape as that of the wooden piece 1 can be adopted.

  Moreover, in the said embodiment, the structure using the wooden piece 1 which consists only of timber was demonstrated. However, the present invention is not limited to this, and it is possible to mix the wooden piece 1 with a material that does not become a gas that causes deterioration in welding quality when incinerated. For example, by mixing an adhesive made of such a material into the wooden piece 1, it is possible to make the wooden piece 1 more difficult to change its shape. For example, the wooden piece 1 can be incinerated in a shorter time by mixing the wooden piece 1 with a material having higher combustibility than the main material wood.

  Moreover, in the said embodiment, the board | plate part 4 of the wooden piece 1 demonstrated the structure which is a flat plate. However, for example, when the plate portion 4 is bent into a shape along the surface of the peripheral wall portion 11 a of the header 11 and the wooden piece 1 is installed on the header 11, the two plate portions 4 are connected to the central axis of the header 11. You may arrange | position so that it may line up in the orthogonal direction. As a result, the plate portion 4 comes into surface contact with the surface of the header 11, which is a curved surface, and the wooden piece 1 can be stabilized.

  Moreover, in the said embodiment, the 1st member of this invention demonstrated the structure which is the header 11, and the 2nd member is the stub pipe 12. FIG. However, the present invention is not limited to this, and can also be applied when welding other members. For example, in the present invention, a configuration in which the first member is a heat transfer tube and the second member is a stub tube may be employed. In addition, the first member and the second member do not need to be constituent elements of the boiler. For example, the first member and the second member may be plastic members.

  DESCRIPTION OF SYMBOLS 1 ... Wood piece (positioning jig), 2 ... 1st projection part, 3 ... 2nd projection part, 4 ... Board part (contact part), 4a ... Upper surface (front surface), 4b ... Lower surface (Back side) 10... Header, 11... Pipe header (first member), 11 a... Peripheral wall, 11 b .. Stub tube mounting hole, 12 .. Stub tube (second member), 12 a. hole

Claims (4)

A positioning jig for positioning the first member and the second member to be welded later,
A contact portion for positioning the first member and the second member in contact with the first member and the second member is provided, and is formed of a plant material that can be incinerated. Positioning jig to do.   The positioning jig according to claim 1, wherein the positioning jig is made of only wood. The first member is a header installed inside the boiler, and the second member is a stub tube connected to the header;
A first protrusion inserted into a stub tube mounting hole provided in the header;
A second protrusion inserted into the hole of the stub tube;
The positioning jig according to claim 1 or 2, further comprising: a plate portion with which an end portion of the stub tube is brought into contact with a front surface and the header is brought into contact with a rear surface. A member positioning method for positioning a first member and a second member to be welded later,
A member placement step of placing the first member and the second member apart by interposing the positioning jig according to any one of claims 1 to 3,
A temporary attachment step of temporarily attaching the first member and the second member by welding a part of the first member and the second member after the member arrangement step;
A positioning jig removing step of removing the positioning jig after the tacking step.

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