JP3384771B2 - Forged piece used as crater for gas pressure welding, method for producing crater for gas pressure welding using the same, and burner for gas pressure welding using the crater for gas pressure welding - Google Patents

Description

Detailed Description of the Invention

[0001]

SUMMARY OF THE INVENTION The present invention relates to a ring burner used in a gas pressure welding method in which end portions of reinforcing bars are pressed and joined concentrically with each other, and in particular, a butt pressure contact surface portion of a reinforcing bar to be subjected to gas pressure welding, and A gas pressure welding crater piece with a new structure that can reliably heat a predetermined range including its vicinity, a new method of manufacturing a gas pressure welding crater piece using the same, and a new method using the gas pressure welding crater piece. It is intended to provide a burner for gas pressure welding having a structure.

[0002]

2. Description of the Related Art Most of the joining of steel rods for reinforced concrete in the field of civil engineering and construction is carried out by a gas pressure welding method, which generally involves concentric butting of the ends of the reinforcing bars. Pressurization and depressurization are repeated multiple times, and the joint is acetylene gas
By heating with a flame of an oxygen mixed gas and pressing them simultaneously, two steel rods are joined and integrated into one.

In a general gas pressure welding method which has been performed for a long time, a method of heating a pressure welding portion of a reinforcing bar from all directions appropriately and uniformly is adopted by using a ring burner which surrounds a joint portion in an annular shape. As shown in the perspective view of the conventional ring burner of FIG. 12, the ring burner has a tip end sided bifurcated into a blow tube attachment port 6 connected to a blow tube (not shown) so that the gas pressure welding target rebars 7, 7 are A curved gas supply pipe portion 5 is provided so as to surround the outer peripheral side in an arc shape, and a cylindrical crater tip 8 scattered along the circumferential direction is provided on the inner peripheral surface of the arc-shaped tip end side of the gas supply pipe portion 5. , 8, ... are projected so that the tips of the crater tips 8,8, ... are directed toward the center of the arc shape and are arranged radially around the gas pressure welding target rebars 7,7. In the case of pressure welding, the target iron for gas pressure welding is The end faces of 7, 7 are coaxially butted against each other and pressed against each other at a predetermined pressure, and a combustion gas is supplied from a blow pipe attachment port 6 connected to a blow pipe (not shown), and each crater tip 8, 8 ,. By radiating and burning gas from the tip, the joint end faces of the gas pressure welding target rebars 7, 7 are heated, and pressure welding is performed while visually checking the heating state of the rebars 7, 7.

In the conventional gas pressure welding work, the flames from the ring burner crater tips 8, 8, ... Are arranged so as to concentrate on the target rebar, but each crater tip 8, 8 ,. Combustion gas emitted from ... is formed so as to concentrate on the respective rebars because it is necessary to maintain a predetermined combustion temperature, and each crater tip 8, 8, ... The overall flame is, at the same time, orthogonal to the rebar axis. Since it is radiated to the rebar as a thin flat flame, it follows the gas pressure welding work standard `` For each rebar, at least within the range of the width corresponding to the diameter of the rebar from the abutting surface, the rebar is quickly and uniformly. Heat to about 1200 ° C at core temperature. "
Make sure that the ring burner itself does not change the distance from the axis of the reinforcing bar of each crater tip 8, 8, ... It is necessary to perform a work that requires a very high degree of skill to make a parallel translation by the amount of the required width, and during the gas pressure welding work, the pressure welding operator relied on his abundant experience and intuition. Continue the heating work while moving the ring burners to both sides of the gas pressure welding target reinforcing bars 7 and 7 in the axial center direction with a quick and delicate sensation, respectively. Prevent heating and
In order to prevent the formation of an oxide film at the joints of the reinforcing bars 7 and 7 and to form a flat fracture surface, the joints are surrounded by a reducing flame shield, and careful attention is paid to prevent unnecessary air from entering the joints. Difficult work operations are required to maintain optimal conditions, such as having to pay attention.

In order to solve the problems of securing human resources and work efficiency that are derived from such highly specialized work contents, an improved technique related to gas pressure welding has hitherto been disclosed in Japanese Patent Laid-Open Publication No. Hei 7 (1998).
Various proposals have been made as disclosed in Japanese Patent Laid-Open No. 214343 and Japanese Patent Laid-Open No. 9-271963. For example, Japanese Unexamined Patent Publication No. 7-214343 discloses a method for preventing the formation of an oxide film at a joint by applying a coating agent containing a deoxidizer and a dehydrogenator to the joint end surface of a steel bar. Further, in Japanese Patent Laid-Open No. 9-271963,
There has been proposed a gas pressure welding device capable of controlling the flame to follow the joint. However, neither of these improves the ring burner itself and makes the flame condition advantageous, but by applying a coating agent to the reinforcing bar to be pressure-welded or automating the pressure-welding work, a conventional ring burner was adopted. This is an attempt to improve the precision and efficiency of the pressure welding work, and has a drawback that the material cost and the equipment cost increase.

In view of the above-mentioned circumstances, even if the highly skilled technique is required as before, or expensive reinforcing bar material or gas pressure welding device is not used, the gas pressure welding target rebars 7 and 7 are In addition to being able to heat the joint part uniformly and properly, an oxide film is formed due to the invasion of air into the joint part, resulting in a flat fractured surface at the pressure contact and the welded part, making it impossible to secure sufficient mechanical strength. With a deep interest as one of those who have been involved in this industry for many years, it has been repeated research and trial production of a new burner for gas pressure welding, which has improved the performance of the part usually called a crater tip, We have reached the stage where it can be provided as a product that facilitates pressure welding work and that can obtain good pressure welding performance, but its structure is more complex than the previous ring burner. The production efficiency when producing various gas pressure welding burners according to the diameter of the pressure welding target reinforcing bars 7, 7 is deteriorated, resulting in a large number of manufacturing processes and a rise in price. It was a new drawback.

[0007] The present invention has begun further development and research toward the practical application of a novel burner for gas pressure welding, which can secure good gas pressure welding performance and enhance the productivity thereof, and has conducted trial and error over a long period of time. After repeating many trials and experiments, we succeeded in realizing a gas pressure welding crater piece with a new structure that can eliminate the problems from the past, as shown in the drawings below. The configuration of the present invention will be described in detail together with some embodiments that are representative of the present invention.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As will be clearly understood from the embodiments representative of the present invention shown in the drawings, the forging piece body as a gas pressure welding crater piece basically included in the present invention is as follows. It consists of a composition. That is, the crater surface forming portion of the bridge body integrally formed with the horizontal rod-shaped gas supply passage forming portion on the back side of the crater surface forming portion having a relatively thick plate is arranged at the center of the crater surface. At least 1 each above and below the central crater
Reinforcing bar craters for each axial center position are arranged in a row in a symmetrical manner, and crater sections for reinforcing bar diameter are arranged in a row in a symmetrical manner on the left and right sides of the central crater section and each reinforced core axis crater section. In addition, between the craters adjacent to the central crater and the reinforced caliber corresponding to the diameter of the reinforcing bar, it is arranged vertically and horizontally around each crater surface so that it is in communication with the outer peripheral edge of the bridge body. And at least one or more guide recesses for drilling gas holes are provided on the crater surfaces of the central crater portion and the reinforcing rod diameter-corresponding crater portion. It is a forged piece.

The forging piece body having the gas-pressure welding crater piece of this basic construction is shown as a more specific construction.
A central crater in which the crater surface forming portion of the piece body integrally formed with a horizontal bar-shaped gas supply passage forming portion on the back side of the crater surface forming portion that is a relatively thick plate is arranged in the center of the crater surface. At least one rebar axis center crater is symmetrically arranged in a row above and below the section, and the center crater section and each rebar axis center crater section correspond to the rebar diameter respectively. The craters are arranged in a line and symmetrically, and between the craters adjacent to the central crater and the reinforced caliber craters, they are arranged vertically and horizontally around each crater surface and communicate with the outer periphery of the piece body. And the guide recesses for drilling at least one gas hole are provided on each of the crater surfaces of the central crater portion and the reinforcing rod diameter-corresponding crater portion. The gas supply passage forming portion has the crater surface shape at one end side in the axial direction. The forged piece body to the gas pressure for the crater piece to gist configuration shall become formed predetermined angle bent section side.

More specifically, the crater surface formation of the piece main body in which a horizontal rod-shaped gas supply path forming portion is integrally formed on the back side of the crater surface forming portion having a relatively thick plate shape. Part, at the top and bottom of the central crater located at the center of the crater surface, at least one for each rebar axis center position, the crater sections are arranged symmetrically in a row, and for the central crater section and each rebar axis center On the left and right sides of the crater, the reinforced caliber pits are arranged symmetrically in a row, and between the craters adjacent to the central crater and the reinforced caliber crater, each crater surface is surrounded by Air supply grooves are arranged vertically and horizontally so that they are in communication with the outer periphery of the bridge body, and at least one or more gas holes are formed on each crater surface of the central crater and the reinforced caliber caliber. It is formed to have a crater surface provided with a guide recess for installation. On the other hand, in the gas supply path forming portion, one end side in the axial direction is bent and formed at the crater surface forming portion side by a predetermined angle, and the gas supply path forming portion is built up at a portion close to the crater surface forming portion on the other end side. It can be said to be a forged piece body having a gas-pressure-contacting crater piece and having a structure in which a portion is formed.

The piece body has a function of forming the body of the gas pressure contact crater piece, and the crater surface forming portion and the gas supply path forming portion must be integrally formed, and the whole is forged. Formed in a highly airtight manner by casting,
Unless perforated, it is formed into a dense ingot shape that does not allow gas to pass through, and post-processing by cutting only the gas holes of each crater part and the connection part of the gas supply pipe part that requires some accuracy. It is most desirable to cold forge and manufacture materials such as brass, copper, bronze, ultra-soft steel, carbon steel, soft stainless steel, aluminum, and magnesium alloys in consideration of production efficiency. Depending on the material to be used and the manufacturing conditions, it can be manufactured based on a casting or sintering technique, or a non-metal material having heat resistance can be injection molded.

The crater surface forming portion functions to form a central crater portion, a reinforcing rod axial center crater portion and a reinforcing rod diameter corresponding crater portion, and also to form an air supply groove portion, and forms a gas supply path. It must be integrally formed as an attachment to the part, has sufficient heat resistance to flames, and is free-cutting that enables good cutting to facilitate the formation of gas holes. It is desirable to form it from a material having

The central crater portion is formed substantially at the center of the crater surface forming portion and has a function of enabling the formation of gas holes, and the projection end surface is formed with a guide recess for gas hole drilling. Reinforcing bar axial center crater function is located above and below the central crater to enable gas holes to be formed parallel to the axial center of the rebar to be pressure welded during pressure welding work. In the same way as the central crater, a guide recess for drilling gas holes should be formed on the tip end face, and the caliber corresponding to the diameter of the reinforcing bar should be the central crater and the crater for the core of the reinforcing bar. Located on the left and right of the, it performs the function of forming one gas hole or a plurality of gas holes spaced at an appropriate interval, which are positioned substantially orthogonal to the axial center of the reinforcing bar to be pressed during the pressing work. Auxiliary craters outside each crater within the range that does not reduce the supply gas pressure. Form it is also possible to.

The guide recess has a function of displaying the drilling position of the gas hole and accurately guiding the tip of the cutting tool when drilling the gas hole. It is desirable to set the height to a hole shape such as a spherical shape, a conical shape, a polygonal pyramid shape, or a cylindrical shape so that the cutting by the tool is not alienated, and when forging the forging piece body in consideration of productivity. It is preferable to perform stamping and molding at the same time.
In addition, the air supply groove portion has a function of allowing the fresh air around the crater portion to flow to the respective crater portions, and the crater portion for the central crater portion, the reinforcing rod shaft center crater portion and the reinforcing rod diameter corresponding crater portion is provided. It should be a groove formed between adjacent crater parts, and it is desirable to form it by a combination of flat straight lines that do not obstruct the air flow or gentle flat curved lines, which facilitates molding by forging As described above, it is preferable that the groove shape is such that the expanded cross section has a slight draft.

Furthermore, in the forged piece, the connecting portion to the gas supply pipe portion provided on one end side or both end sides of the piece main body gas supply passage forms an angle of its axis with respect to the axis of the gas supply passage. If it is restricted to about 135 to 150 degrees in a plane that passes through the gas supply passage and the substantially central axis of the central crater, it is extremely convenient to form a crater piece corresponding to the shape and size of the gas pressure burner. Can be good.

[0016]

[Related invention 1] In relation to the forged piece used as the above-mentioned gas pressure welding crater piece, the present invention relates to a method for producing a gas pressure welding crater piece for manufacturing a gas pressure welding crater piece using the forged piece. The gist of the configuration is that the crater surface formation of the piece main body in which a horizontal rod-shaped gas supply path formation portion is integrally formed on the back side of the crater surface formation portion that is a relatively thick plate shape. Part, at the top and bottom of the central crater located at the center of the crater surface, at least one for each rebar axis center position, the crater sections are arranged symmetrically in a row, and the central crater section and each rebar axis center On the left and right sides of the crater, the reinforced caliber pits are arranged symmetrically in a row, and between the craters adjacent to the central crater and the reinforced caliber crater, each crater surface is surrounded by The air supply groove is arranged vertically and horizontally so that it can communicate with the outer peripheral edge of the bridge body. Further, for each forged piece to be a gas pressure welding crater piece, at least one or more guide recesses for forming gas holes are provided on each crater surface of the central crater portion and the reinforcing rod diameter corresponding crater portion, Each guide recess is provided with a gas hole reaching the gas supply passage forming portion at a predetermined angle, and a gas supply passage having a predetermined inner diameter is formed only from one end side or both ends of the gas supply passage forming portion. , The shape and dimensions of the gas pressure burner to be used on one side or both ends of the gas supply path in a plane where the angle with respect to the axis of the gas supply path passes through the approximate axis of the gas supply path and the central crater. The basic structure is to appropriately cut the connecting portion of the gas supply pipe portion which is regulated within the range of about 135 to 150 degrees according to the above.

If the method for producing the gas pressure contact crater piece included in the present invention is shown as a more specific structure, a horizontal rod-shaped gas supply is provided on the back side of the crater surface forming portion having a relatively thick plate shape. The crater surface forming portion of the piece body integrally formed with the passage forming portion has at least one crater portion for the axial center position of one line above and below the central crater portion arranged in the center of the crater surface. In addition to symmetrically arranging, the central crater part and the reinforcing bar diameter center crater parts are arranged symmetrically in a row on the left and right sides of the central crater part and each reinforcing bar shaft center crater part respectively. Between adjacent craters in the crater area, there are air supply grooves that are arranged vertically and horizontally around each crater surface and are in communication with the outer peripheral edge of the bridge body. At least one gas on each crater surface of the crater While providing a guide recess for drilling, the gas supply passage forming portion is formed by bending one end side in the axial direction of the gas supply passage forming portion toward the crater surface forming portion side by a predetermined angle. For the forged piece body to be the crater piece,
Each guide recess is provided with a gas hole reaching the gas supply passage forming portion at a predetermined angle, and a gas supply passage having a predetermined inner diameter is formed only from one end side or both ends of the gas supply passage forming portion. , The shape and dimensions of the burner for gas pressure welding to be used at one end or both ends of the gas supply path in a plane where the angle with respect to the axis of the gas supply path passes through the approximate axis of the gas supply path and the central crater. About 13
It can be said that the gas pressure welding crater piece manufacturing method is characterized in that the connection portion of the gas supply pipe portion, which is regulated within the range of 5 to 150 degrees, is appropriately cut.

More specifically, the formation of the crater surface of the main body of the piece, which is formed by integrally forming a horizontal rod-shaped gas supply passage forming portion on the back side of the crater surface forming portion having a relatively thick plate shape. Part, at the top and bottom of the central crater located at the center of the crater surface, at least one for each rebar axis center position, the crater sections are arranged symmetrically in a row, and for the central crater section and each rebar axis center On the left and right sides of the crater, the reinforced caliber pits are arranged symmetrically in a row, and between the craters adjacent to the central crater and the reinforced caliber crater, each crater surface is surrounded by Air supply grooves are arranged vertically and horizontally so that they are in communication with the outer periphery of the bridge body, and at least one or more gas holes are formed on each crater surface of the central crater and the reinforced caliber caliber. Shaped to have a crater surface with a guide recess for installation On the other hand, the gas supply path forming portion has one end side in the axial direction thereof bent and formed at a predetermined angle on the crater surface forming portion side, and at a location close to the crater surface forming portion on the other end side. With respect to the forging piece body which is the gas pressure welding crater piece formed with the built-up portion, each guide recess is provided with a gas hole reaching the gas supply passage forming portion at a predetermined angle, and at the same time, the gas supply passage forming portion is formed. Perforating a gas supply passage with a predetermined inner diameter that is a penetrating shape from only one end side or both ends,
Depending on the shape and size of the gas pressure welding burner to be used, on one end side of the gas supply path, the angle with respect to the axis of the gas supply path is in a plane that passes through the approximate axis of the gas supply path and the central crater. The connection part of the gas supply pipe part that regulates within a range of approximately 135 to 150 degrees is appropriately cut, and the connection part of the gas supply pipe part that reaches the inside of the buildup part is appropriately cut on the other end side. This is a method for manufacturing a gas pressure welding crater piece, which has a structure configured to be processed.

The step of forming a gas hole and the step of forming a gas supply passage in the forging piece may be performed in any order, and when the forging piece is manufactured, the same forging is performed. It is also possible to punch and punch the gas supply path during the process, and the order of the step of punching the gas supply path and the step of cutting the connection part of the gas supply pipe part is performed first. If so, the same desired structure can be obtained. In addition, the drilling angle of the gas hole is such that the central crater is drilled so as to be substantially orthogonal to the axial center of the rebar to be pressure-welded, and the other craters surrounding it are burned with the combustion gas released around the central crater. It is preferable to perforate each of them so that they are slightly radially outward so as to form a conical shape that expands in the direction.

[0020]

[Related invention 2] Further, the present invention relates to a forging piece which is a crater piece for gas pressure welding and constitutes a skeleton of the present invention, and a method for manufacturing a crater piece for gas pressure welding using the above-mentioned forging piece body. A gas pressure welding burner using the gas pressure welding crater piece having the following configuration, which is manufactured by the method for manufacturing the forged piece and the gas pressure welding crater piece, is also included as a related invention. That is, each guide recess is provided with a gas hole reaching the gas supply passage forming portion at a predetermined angle, and a gas supply passage having a predetermined inner diameter is formed only from one end side or both ends of the gas supply passage forming portion. The shape of the burner for gas pressure welding to be used on one side or both ends of the gas supply path that is drilled in a plane where the angle with respect to the axis of the gas supply path passes through the gas supply path and the approximate axis of the central crater. , A plurality of gas pressure welding crater pieces, which are formed by appropriately cutting the connecting portion of the gas supply pipe portion, which is regulated within a range of approximately 135 degrees to 150 degrees according to the dimensions, are pressure-welded around the rebar to be pressure-welded. Arrange them at equal intervals along a circle drawn with the optimum separation distance radius, connect a plurality of gas supply pipe parts located outside the same circle, and connect all the gas pressure welding crater pieces to one. Connected to the blowpipe mounting port The connection was made by structure to a gas pressure for burners to the basic.

More specifically, each of the guide recesses is provided with a gas hole reaching the gas supply passage forming portion at a predetermined angle, and a penetrating shape is provided only from one end side or both ends of the gas supply passage forming portion. A gas supply passage with a predetermined inner diameter is drilled, and the gas supply passage is used at one end side of the gas supply passage in a plane where the angle with respect to the axis of the gas supply passage passes through the gas supply passage and the substantial axis of the central crater. Depending on the shape and size of the burner for gas pressure welding, the connection part of the gas supply pipe part, which is regulated within a range of approximately 135 to 150 degrees, is appropriately cut, and the other end side has meat as necessary. A plurality of gas pressure welding crater pieces, which are obtained by appropriately cutting the connection part of the gas supply pipe that reaches the inside of the embankment, are mutually equal along a circle drawn with the optimal separation radius for pressure welding centered on the rebar to be pressure welded. If you place them at intervals, , Gas pressure welding with a structure in which a plurality of gas supply pipes located outside the same circle are connected and all the gas pressure welding crater pieces are connected so as to communicate with one blower pipe mounting port It can be said that it is a burner for use.

The gas pressure welding burner uses a minimum of two gas pressure welding crater pieces, and the reinforcing rods to be pressure welded are faced to each other so as to be sandwiched between them by a predetermined distance, and are connected by a gas supply pipe, In addition to those that can be formed, it is also possible to arrange a total of three gas pressure welding crater pieces at each vertex of the plane regular triangle centering on the pressure welding target reinforcing bar, and connecting each with a gas supply pipe. The gas supply pipe is inserted and connected so as to reach the inside of the build-up part by using the build-up part formed near the crater surface formation part on the other end of the gas supply path formation part. It is also possible to adopt a structure that avoids the extreme curvature of the part.

The gas supply pipe section has a function of connecting the gas pressure welding crater piece and the blow tube attachment opening with sufficient strength, and a function of supplying combustion gas from the blow tube attachment opening to each piece body. Therefore, the burner for gas pressure welding must be formed so as to have the strength for maintaining the shape and the solidity for ensuring the airtightness of the combustion gas flowing inside, and at the same time, It should have a structure that avoids overheating due to flames as much as possible,
In addition to being made of a material with excellent fire resistance and heat insulation, it is also possible to coat the outer peripheral wall with a heat resistant heat insulating material, and the crater surface of the crater piece for gas pressure welding in the middle part. It may be formed so as to be bent on the side opposite to the forming portion so as to avoid the flame and to be arranged at a sufficient distance from the reinforcing bar to be pressure-welded at the time of pressure welding.

The blow pipe mounting port is provided with a combustion gas valve, an oxygen valve,
And the function of connecting the gas supply pipe part to the blow pipe having a grip pipe and the like, and the function of distributing and supplying the combustion gas supplied from the blow pipe to the gas supply pipe part. It is essential to ensure airtightness to prevent gas leakage, and it is desirable to provide a connecting portion having a detachable structure that can be easily attached and detached, or to connect to the blow pipe by screw connection or the like that can ensure high airtightness. Hereinafter, the structure of the present invention will be described in detail together with the representative embodiments of the present invention shown in the drawings.

[0025]

[Embodiment 1] A plan view of a forged piece used as a crater piece for gas pressure welding shown in FIG. 1, a side view of the forged piece shown in FIG. 1 and a forged piece shown in FIG. 3 shown in FIG. The case shown in each of the front views seen from Fig. 1 is a gas pressure welding included in the present invention having a basic structure in which the crater surface forming portion and the gas supply passage forming portion are integrally formed by cold press working. 1 shows a typical example of a forged piece used as a crater piece.

The forged piece 2 has a crater surface forming portion 3 and a gas supply path forming portion 4 which are integrally formed by cold pressing a brass rod material. A central crater portion 31 is formed in the center of the central crater portion 31, and reinforced axial center position crater portions 32, 32 are formed above and below the central crater portion 31, respectively. , 32 are arranged and formed on the left and right sides of the rebar diameter corresponding to the reinforcing bar diameter. The crater portions 32, 32, ... Are formed, and are provided vertically and horizontally around each crater surface and are connected to the outer peripheral edge of the piece body for air supply of a predetermined width and a predetermined depth. The groove portions 34, 34, ... Are formed in a shape that widens toward the surface side of the crater surface forming portion 3. It is further central crater portion 3
1. Reinforcing bar axial centering craters 32, 32 and reinforcing bar diameter-corresponding craters 33, 33, ... Are formed in a substantially spherical shape for drilling gas holes at positions separated by a predetermined distance. The formed guide recesses 35, 35, ... Are molded.

The gas supply path forming portion 4 has a surface, one end side of which in the axial direction, passes through substantially the center axis of the gas supply path 42 and the central crater portion 31 formed by post-processing toward the crater forming surface portion 31 side. It is bent and formed at an angle A of about 135 to 150 degrees in the inside, and is projected toward the crater formation surface portion 31 side at a position close to the crater formation surface portion 31 on the other end side. A built-up portion 41 is formed.

[0028]

[Embodiment 2] The case shown in the plan view of the gas pressure welding burner in FIG. 4 shows an embodiment included in the gas pressure welding burner using the gas pressure welding crater piece of the present invention. The connecting portion 43 of the gas supply pipe portion 5 provided on one end side of the supply passage 44 is approximately 13 with respect to the axis of the gas supply passage.
The two forged pieces 2, 2 that were bent and formed at an angle of 5 degrees,
It is connected to one blow pipe mounting port 6.

The burner 1 for gas pressure welding has a forging piece as shown in FIGS. 1 to 3 at each tip of a gas supply pipe portion 5 which is branched and extended in a plane V shape from one blow pipe attachment port 6. Each crater part 31, 32, 3 on the crater surface forming part 3 of 2
2, 33, 33, ... Gas holes that reach the gas supply path 44 are drilled, and the gas supply path 44 is drilled from the end surface of the gas supply path forming portion 4 on the other end side that is not bent. A lid prepared in advance is joined to the opening formed by perforation of the end face on the other end side to close it, and the angle of the gas supply passage forming portion 4 with respect to the axis of the gas supply passage 44 is determined by the gas supply passage 44.
In the plane that passes through the substantially central axis of the central crater portion 31, a connecting portion 43 that connects the end portion of the gas supply pipe portion 5 to the one end side of the gas supply passage forming portion 4 that is bent at an angle of approximately 135 degrees is provided. The gas pressure welding crater pieces 2, 2 formed by cutting are connected and integrated by welding, brazing, screw connection, or the like, and the pair of gas pressure welding crater pieces 2, 2 are used for pressure welding.
Are sandwiched at intervals suitable for gas pressure contact, and are arranged to face each other.

The crater piece 2 for gas pressure welding has a central crater portion 3 thereof.
1 is pierced so as to be substantially orthogonal to the center of the rebar 7 to be pressure-contacted when gas-pressure-contacting, and the rebar diameter-corresponding craters 33, 33 and the rebar shaft center position craters 32, 32 formed around the perforation , ..., when the gas holes of the central crater portion 33 are set to 0 degrees, as shown by the chain line arrows in Fig. 1, the gas holes are in the range of 3 to 23 degrees toward the outside. Perforations are made in a radially inclined state, and the degree of inclination is such that the perforation angle can be selected over the range shown by the chain line in FIG. 3, and the axis of the gas hole is In addition to the holes drilled toward the center of the gas supply passage 44, the gas supply passage 44 may be formed so as to open tangentially on the circumferential surface side.

[0031]

Embodiment 3 In the case shown in the plan view of the gas pressure welding burner using the three gas pressure welding crater pieces in FIG. 5, three gas pressure welding crater pieces 2 ', 2', 2'are suitable. The burner 1 for gas pressure welding, which is arranged in the above position, and the gas supply passage 44 is bent at one end of the gas supply pipe portions 6 and 6 which are attached to the blow pipe attachment port 6 in a plane V shape. One end side remains closed, and a gas pressure welding crater piece 2'having a concentric connecting portion 43 cut to the other end side is connected in a substantially concentric manner,
A gas pressure welding crater piece 2'is also connected to the tip of the other gas supply pipe portion 6 concentrically with the other end side of the same gas supply path 44 which is not bent. To the one end side of the crater piece 2'for bending about 135 degrees, a base end portion of a gas supply pipe portion 5 which is bent in a substantially L-shape in a plane is connected so as to surround the reinforcing bar 7 to be pressure-welded at the time of pressure-welding. At the tip of the L-shaped gas supply pipe portion 5, a gas pressure welding crater piece 2 ′ whose other end is bent is closed, and a total of three gas pressure welding portions are connected. Tinder pieces 2 ', 2',
Each of 2'is configured to be separated from each other by an optimum distance for gas pressure welding around the pressure welding target reinforcing bar 7 at the time of gas pressure welding and to be arranged at the vertices of a regular equilateral triangle.

[0032]

[Embodiment 4] The case shown in the plan view of the gas pressure welding burner using the four gas pressure welding crater pieces of FIG. 6 is the four gas pressure welding crater pieces 2 ', 2', ... 1 shows a configuration of a typical gas pressure welding burner 1 having the following features. The gas pressure welding burner 1 has two straight tubular gas supply pipe portions 5, 5 extending in a plane V shape from a blow pipe attachment port 6. One end of each gas pressure welding crater piece 2 ', 2'which is formed so that both ends of the gas supply passages 44, 44 are penetratingly connected to each tip end of each of the other ends of the gas pressure welding crater pieces 2', 2 '. On the end side, the gas supply pipe portion 5, which is bent at an angle of approximately 150 degrees, with the central portion in the longitudinal direction of the axial direction facing the pressure welding target reinforcing bar 7 side during gas pressure welding,
5 is connected to the base end portions of the gas supply pipe portions 5, 5
The gas pressure welding tip units 2 ', 2', 2 in total are connected to the tip end of each of the gas pressure welding tip units 2 ', 2 with their other ends closed. The central crater portions 31, 31 of the gas pressure welding crater pieces 2 ′, 2 ′, which are arranged at the respective apex positions of a regular quadrangle around the pressure welding target reinforcing bar 7 and face each other.
Are located diagonally.

[0033]

[Fifth Embodiment] The gas pressure welding burner shown in the last FIG. 7 is also an example in which four gas pressure welding crater pieces are used in the same manner as in the above-mentioned embodiment, and in the case of this embodiment, four gas pressure welding burner pieces are used. 2 shows another configuration of the gas pressure welding burner 1 having the gas pressure welding crater pieces 2 ′, 2 ′, ..., Arrangement of a total of four gas pressure welding crater pieces 2 ′, 2 ′,. The position and the shape and structure of the gas supply pipe portions 5 and 5 that connect them to each other are basically the same as those shown in the fourth embodiment, but are extended from the blow pipe attachment port 6 in a plane V shape. , The left and right gas pressure welding crater pieces 2 ′, 2 ′ connected to the gas supply pipe portions 5, 5 are curved and extended so as to be set to be larger than the outer diameter dimension of the reinforcing bar 7 to be pressure welded. It has become a thing.

The gas supply pipe portions 5, 5 extending from the blow pipe attachment port 6 have a portion having a distance larger than the outer diameter dimension of the rebar 7 to be pressure welded, substantially the same as the outer diameter dimension of the rebar 7 to be pressure welded. Or, it extends in a parallel shape over a longer range than that, and the other end side of the gas pressure welding crater pieces 2 ', 2'is connected to each of these tips, for a stronger connection. In order to obtain it, it is assumed that a built-up portion 41 is formed in the vicinity of the crater surface forming portion 3 on the other end side of the gas pressure welding crater pieces 2 ', 2', as shown in FIG. The gas supply pipe section 5 can be configured to be connected in a state indicated by a chain double-dashed line in the figure.

[0035]

The forging piece 2 of the present invention having the above-described structure is substantially concentric with the gas supply path forming portion 4, as shown in the side view of the cross-sectioned forging piece 2 of FIG. Forming a gas supply passage 44, and as shown in the side view of the connection example of the gas supply pipe portion of FIG. 9, a connecting portion 43 for connecting the gas supply pipe portion 5 to the end portion of the gas supply passage 44 is cut. The gas supply passage 44 is formed as a gas pressure contact crater piece 2 ′, and the end of the gas supply passage 44 bent toward the crater surface forming portion 3 has an angle with respect to the gas supply passage 44 and A connecting portion 43 regulated to an angle A of approximately 135 degrees is formed in a plane that passes through the substantially central axis of the central crater portion 31, and is shown in a side view of another example of connecting the gas supply pipe portion in FIG. 10. like,
The angle with respect to the gas supply passage 44 is about 150 in the plane passing through the substantial axis of the gas supply passage 44 and the central crater portion 31.
It is also possible to use the connecting portion 43 regulated to the angle B of degrees.

Further, as shown in FIG. 2, a built-up portion 41 is formed at a position close to the crater surface forming portion 3 at the end of the gas supply passage forming portion 4, and as shown by a chain double-dashed line in FIG. Supply pipe section 5
It is also possible to form so that they can be connected to each other, and further, as shown in FIG.
Each of the gas holes 2, 33, 33, ... Can be drilled toward the center of the gas supply passage 44, and can also be drilled to the extent of being tangential to the inner peripheral wall surface of the gas supply passage 44. It is possible to perform perforation processing by setting an appropriate angle in accordance with the diameter dimension of the reinforcing bar 7 to be pressure-welded.

In the burner 1 for gas pressure welding shown in FIG. 4, when the blow pipe attachment port 6 is connected to a blow pipe having a combustion gas valve, an oxygen valve, a grip pipe, etc. The combustion gas discharged from the holes burns and radiates a flame, and a pair of gas pressure welding crater pieces 2'and 2'that face each other are separated from each other by a distance suitable for gas pressure welding. The flame to be pressed is sandwiched, and a flame is blown so as to spread over the entire circumferential wall surface of the bar to be crimped 7 as indicated by the chain line arrow in the figure, so that the joint portion of the bar to be crimped 7 is heated uniformly.

The gas pressure welding burner 1 shown in FIG. 5 has three gas pressure welding crater pieces 2 ', 2', 2'which are arranged in planes so as to be positioned at the respective vertices of an equilateral triangle centered on the pressure welding target reinforcing bar 7.
From each of the above, the flame is evenly sprayed on the entire circumferential wall surface of the rebar 7 to be pressure-welded to uniformly heat, and all the gas supply pipe parts 5, 5, 5 are required to avoid the flame as necessary. Since it is bent and formed, it is possible to improve the durability and life of the gas pressure welding burner 1 without directly receiving a flame.

The burner 1 for gas pressure welding shown in FIG.
The middle part of the gas supply pipe parts 5, 5 connecting the two gas pressure welding crater pieces 2 ′, 2 ′ on the left and right respectively
3, Bending so as to project toward the opposite side, and configured so as to separate from the rebar 7 to be pressure welded by a predetermined distance during pressure welding work, and damage caused by overheating of the gas supply pipe parts 5, 5. Is to prevent. Like the gas supply pipe sections 5 and 5 shown in the plan view of the gas pressure welding burner 1 having an unfavorable structure in FIG. 11, the gas pressure welding burner 1 penetrates inside the optimum separation radius R from the crater surface 3 to the rebar 7 to be pressure welded. Can be avoided.

The gas pressure welding burner 1 shown in FIG. 7 has a pair of left and right extending from the blowing pipe mounting port 6 shown in the plan view of the gas pressure welding burner 1 of the typical structure shown in FIG. As is clear from comparison with the gas pressure welding burner in which the distance between the gas supply pipe portions 5 and 5 is smaller than the diameter D of the pressure welding target reinforcing bar 7, a pair of left and right gas extending from the blow pipe mounting port 6 is clearly shown. It is possible to set the distance between the supply pipe portions 5 and 5 to be separated from each other to be larger than the diameter D of the pressure welding target reinforcing bar 7, and the pair of left and right gas extending the pressure welding target reinforcing bar 7 from the blowing pipe mounting port 6 during the pressure welding work. It is movable and operable so as to be located between the supply pipe parts 5, 5, and is connected by connecting so that the end of the gas supply pipe part 5 reaches the inside of the built-up part 41 as shown in FIG. Connection strength High, and those having improved durability.

[0041]

[Effects] As described above, according to the forging piece body which is the gas pressure welding crater piece of the present invention, the crater piece individually designed for each diameter of the pressure-welding rebar is individually machined from the previous case. It is not possible to manufacture and supply promptly in response to the demand for gas pressure burners, and to receive an order. Although the lead time from shipping to shipping tended to be long and expensive, eliminating all of these problems, we made the same shape for almost all diameters of commonly used reinforcing bars. By using a forged piece that is manufactured in advance, the gas supply path and gas hole are punched and completed according to the diameter of the reinforcing bar to be pressure-welded, and the number of parts required for inventory is significantly reduced. To be able to Together, by molding by forging to shaping detail, it reduces the cutting portion comes to have a very Xiu features that it is possible to reduce the number of manufacturing steps by a large margin.

In particular, both ends of the gas supply path forming portion of the forging piece are connected at a gas supply pipe portion connection angle or gas hole drilling angle according to the diameter of the reinforcing bar to be pressure welded, or as a gas pressure welding burner. Since it has a structure that can sufficiently cope with the connection angle etc. of the gas supply pipe part depending on the crater arrangement structure, the connection angle of the gas supply pipe part depending on the diameter of the reinforcing bar to be pressure welded By setting the gas hole drilling angle or the connection angle of the gas supply pipe section according to the crater arrangement structure to the optimum one and performing drilling processing, various applications can be produced accurately and in large quantities. It is possible to provide a gas pressure welding crater piece with a nearly ideal structure that can radiate a flame on average over a wide range that could not be obtained with conventional nozzles, and it is very effective for the production of inexpensive gas pressure welding crater pieces with a short delivery time. Big to exert So that the point can be obtained.

Further, in the method for manufacturing a gas pressure welding crater piece using this forging piece, all the gas pressure welding crater pieces connected between the gas supply pipes or at the ends are formed from the same shape of the forging piece. Since it is possible to manufacture, it is possible to use the same molding die, machine tool, jig, etc., and manufacture multiple types of gas pressure welding crater pieces in a single setup using the same mechanical equipment. In addition, since the connection angle of the gas supply pipe part to the gas pressure contact crater piece can also be realized with an optimal connection structure that takes into consideration the flame direction and fogging, the flame radiating from each crater surface Piping that avoids the gas supply pipe section as much as possible is easy, and the connection structure of the gas supply pipe section at the optimum angle can be realized by simply performing a slight cutting process on the necessary portion of the forging piece, Therefore its made The number of man-hours and manufacturing costs are drastically reduced to improve the production efficiency, and it is possible to manufacture a high-performance gas pressure welding crater piece with higher gas pressure welding performance than conventional products. Become.

Further, according to the burner for gas pressure welding using the crater piece for gas pressure welding of the present invention, an angle with respect to the axis of the gas supply passage is provided at one end side or both ends of the gas supply passage.
A gas pressure welding crater piece is formed by appropriately cutting the connecting portion of the gas supply pipe part that regulates within a range of approximately 135 degrees to 150 degrees in a plane that passes through the gas supply path and the substantially axial center of the central crater part. By doing so, it is possible to easily realize a gas pressure welding burner having a shape and size corresponding to various diameters of the reinforcing bar to be pressure welded, and efficiently produce a large number of types of gas pressure welding burner even in small quantities. It is possible and, regardless of the magnitude of demand, it is possible to manufacture and provide a burner for gas pressure welding having a structure optimal for gas pressure welding the reinforcing bars to be pressure welded of various diameters even in a single item, with a short delivery time and at a low price. The entire joint portion of the reinforcing bar to be pressure-welded is surrounded by a homogeneous and stable flame, and the excellent effect that it can be heated under favorable conditions is exhibited.

In particular, the forged piece 2 taken up in Example 1
Is pre-formed in the crater surface forming portion 3 by cold press working, and the guide recesses 35, 35, ... to be drilled at the time of positioning the gas holes are formed as necessary. Can be selected and boring the same recess as a guide, the work of forming a pilot hole is unnecessary, and the number and position of gas holes, the direction of the shaft center, etc. can be set appropriately.
A plurality of types of gas pressure contact crater pieces can be easily manufactured, and one end of the gas supply path 44 is bent toward the crater surface forming portion 3 side. It is also possible to perforate the gas supply passage 44, and by using the built-up portion 41 on the other end side, the gas supply pipe portion 5 is connected in a state of being bent to the side opposite to the crater surface forming portion 3. It is configured to enable the production of a crater piece 2'corresponding to a variety of gas pressure welding burners. It is ideal that the forged piece 2 is stocked as it is and perforated as necessary. Therefore, it is possible to manufacture a different crater piece 2'and to realize a gas pressure burner having an optimum structure corresponding to a reinforcing bar to be pressure-welded.

Burner 1 for gas pressure welding shown in Example 2
Despite being manufactured by using only two crater pieces 2 ′, 2 ′, the crater portions 31, 32, 32 which are scattered on substantially the entire surface of the crater face forming portion 3 , 33, 33, ... The number of gas holes formed and the respective drilling angles are regulated according to the thickness and separation distance of the rebar 7 to be pressure-welded. Combustion gas is discharged almost uniformly without waste, and only two crater pieces 2 ', 2'are used, and more crater pieces 2', 2 ', ... are adopted. Compared to the above, it is much easier to position the rebar 7 at the center position, and the center runout can be minimized even with the parallel movement operation, which is necessary for the pressure welding work. In addition to having the great advantage of facilitating uniform heating of the prescribed area of The reflection of the flame from the outer circumference of the reinforcing bar 7 also becomes a direction that does not directly go to the gas supply pipe parts 5 and 5 as shown by the arrow in the figure, so that damage due to overheating is eliminated and the durability of the burner 1 is finally increased. The effect of increasing is obtained.

Further, as in the gas pressure welding burner 1 of the third and fourth embodiments, three or more crater pieces 2 ',
Even a gas pressure welding burner 1 having a typical structure of 2 ', ... Can be formed by employing a crater piece 2'formed by using the forging piece body 2 of the same shape according to the present invention. In addition, the arrangement of the gas supply pipes 5, 5, ... Is located outside the virtual circumference drawn so as to be in contact with the crater surface forming parts 3, 3 ,. A burner for gas pressure welding 1 can be realized, and deterioration of overheating of the gas supply pipes 5, 5, ... due to a flame can be prevented as much as possible to realize a burner 1 for gas pressure welding having durability. Therefore, the burner 1 for gas pressure welding having an extremely economical and high performance can be obtained.

Although not shown in the drawing, in the gas pressure welding burner 1 using four crater pieces 2 ', 2', ..., each pair of crater pieces 2'which face each other on the left and right sides, The separation distance of 2 ′ is closer than that shown in FIG. 6 (therefore, the arrangement of the central crater portions 31, 31 between the facing gas pressure crater pieces 2 ′, 2 ′ is not diagonally arranged). If it is made to be), the rebar 7 to which the flame emitted from each crater piece 2 ′, 2 ′, ...
The bounce from the outer peripheral surface can be directed in a direction away from the gas supply pipe parts 5, 5 ,.
Further, the advantage that the durability can be increased can be obtained.

Furthermore, the four crater pieces 2'of the fifth embodiment,
In the gas pressure welding burner 1 according to another embodiment using 2 '..., The flame is bent by turning the middle portions of the left and right gas supply pipe portions 5, 5 outward. ，
It is possible to avoid direct spraying to the No. 5 and to prevent melting and realize a safe pressure welding work. Further, the gas pressure welding burner 1 shown in Example 5 is extended from the blow pipe attachment port 6. Even if the pair of left and right gas supply pipes 5 and 5 are not extremely bent, it is possible to set the distance between them to be larger than the diameter D of the rebar 7 to be pressure-welded. Since the rebar 7 to be pressure-welded can be operated to move between the supply pipe portions 5 and 5, it can be provided as the gas pressure burner 1 which is highly evaluated by a skilled worker.

As described above, the forged piece used as the gas pressure welding crater piece of the present invention, the method for manufacturing the gas pressure welding crater piece using the same, and the gas pressure welding burner using the gas pressure welding crater piece, The new configuration makes it possible to achieve the intended purpose evenly, and is particularly easy to manufacture, which is far more economical than the unit price of conventional crater pieces. The work efficiency itself is greatly improved, and it is possible to reliably achieve cost reduction and shortening of manufacturing time, and a stable product supply is guaranteed. In the construction industry, where accurate and prompt response to diverse demands is being sought, it has been highly evaluated as a means of enabling highly accurate and economical gas pressure welding work that is adaptable to the times, and has been widely evaluated. hand Use, is expected to continue to spread.

[Brief description of drawings]

BRIEF DESCRIPTION OF THE DRAWINGS Several examples of a forged piece, a gas pressure welding crater piece using the same, and a gas pressure welding burner, which are representative of the present invention, are shown.

FIG. 1 is a plan view showing the structure of a forged piece body which is a crater piece for gas pressure welding.

FIG. 2 is a side view showing a structure of the forged piece.

FIG. 3 is a front view showing a state of the forged piece viewed from the build-up portion side.

FIG. 4 is a plan view showing a gas pressure welding burner using two forged pieces.

FIG. 5 is a plan view showing a gas pressure welding burner using three forged pieces.

FIG. 6 is a plan view showing a gas pressure welding burner using four forged pieces.

FIG. 7 is a plan view showing another burner for gas pressure welding using four forged pieces.

FIG. 8 is a side view showing a vertical cross section of a forged piece.

FIG. 9 is a side view showing an example of a cutting process of a forged piece in a vertical cross section.

FIG. 10 is a side view showing another example of the cutting work of the forged piece with a longitudinal section.

FIG. 11 is a side view showing a vertical cross-section of still another example of the cutting process of the forged piece.

FIG. 12 is a plan view of a conventional gas pressure burner having a conventional structure.

[Explanation of symbols]

1 Gas pressure welding burner 2 Forged piece (crater piece for gas pressure welding) Tinder piece formed using 2'forged piece 3 Crater formation part 31 Central crater 32 Crater part for the same axial position of the reinforcing bar 33 The same crater part for reinforcing bar diameter 34 Same air supply groove 35 Guide recess 36 Same gas hole 4 Gas supply channel forming part 41 Same built-up part 42 Same gas supply path 43 Connection part (gas supply pipe part) 44 Gas supply channel 5 Gas supply pipe section 6 Blow pipe mounting port 7 Rebar for pressure welding D same diameter R Radius of separation from the crater surface to the rebar to be pressed

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP 2000-102884 (JP, A) JP 11-82944 (JP, A) JP 8-159422 (JP, A) JP 9-239565 (JP, A) JP 9-271963 (JP, A) JP 7-214343 (JP, A) Registered utility model 3059851 (JP, U) Registered utility model 3025023 (JP, U) Registered utility model 3018641 ( (58) Fields investigated (Int.Cl. ⁷ , DB name) B23K 20/00 F23D 14/38 F23D 14/58

Claims (9)

(57) [Claims] 1. A piece main body in which a horizontal bar-shaped gas supply passage forming portion is integrally formed on the back side of a relatively thick plate-like crater surface forming portion, and the crater surface forming portion is the center of the crater surface. At the top and bottom of the central crater portion arranged in the above, at least one each of the reinforcing rod axial center crater portions are arranged symmetrically in a row, and to the left and right of the central crater portion and each reinforcing rod axial crater portion, Reinforcing bar diameter corresponding craters are arranged in a line in a symmetrical manner, and between the central craters and adjacent craters for reinforcing bar diameter are arranged vertically and horizontally around each crater surface. An air supply groove is provided so as to communicate with the outer peripheral edge, and at least one or more guide recesses for drilling gas holes are provided on the crater surfaces of the central crater and the reinforcing bar diameter corresponding crater. A forged piece body that is a crater piece for gas pressure welding, characterized by being 2. A piece main body in which a horizontal bar-shaped gas supply path forming portion is integrally formed on the back side of a relatively thick plate-like crater surface forming portion, and the crater surface forming portion is the center of the crater surface. At the top and bottom of the central crater portion arranged in the above, at least one each of the reinforcing rod axial center crater portions are arranged symmetrically in a row, and to the left and right of the central crater portion and each reinforcing rod axial crater portion, Reinforcing bar diameter corresponding craters are arranged in a line in a symmetrical manner, and between the central craters and adjacent craters for reinforcing bar diameter are arranged vertically and horizontally around each crater surface. An air supply groove is provided so as to communicate with the outer peripheral edge, and at least one or more guide recesses for drilling gas holes are provided on the crater surfaces of the central crater and the reinforcing bar diameter corresponding crater. On the other hand, the gas supply path forming portion has one end side in the axial direction, A forging piece body for use as a gas pressure contacting crater piece, characterized in that it is formed by bending a predetermined angle on the crater surface forming portion side. 3. A piece main body in which a horizontal bar-shaped gas supply passage forming portion is integrally formed on the back side of a relatively thick plate-like crater surface forming portion, and the crater surface forming portion is the center of the crater surface. At the top and bottom of the central crater portion arranged in the above, at least one each of the reinforcing rod axial center crater portions are arranged symmetrically in a row, and to the left and right of the central crater portion and each reinforcing rod axial crater portion, Reinforcing bar diameter corresponding craters are arranged in a line in a symmetrical manner, and between the central craters and adjacent craters for reinforcing bar diameter are arranged vertically and horizontally around each crater surface. An air supply groove is provided so as to communicate with the outer peripheral edge, and at least one or more guide recesses for drilling gas holes are provided on the crater surfaces of the central crater and the reinforcing bar diameter corresponding crater. On the other hand, the gas supply passage forming part is formed to have a crater surface One end side in the axial direction is formed to be bent at a predetermined angle on the crater surface forming portion side, and a build-up portion is formed at a position close to the crater surface forming portion on the other end side. A forged piece body that is a crater piece for gas pressure welding, characterized in that 4. A connecting portion to a gas supply pipe portion provided at either one end side or both end sides of the piece main body gas supply passage defines the angle of its axis with respect to the axis of the gas supply passage to the gas supply passage and the center. Approximately 135 in the plane that passes through the approximate axis of the crater
4. A forging piece body for use as a gas pressure contact crater piece according to claim 1, wherein the forging piece is formed so as to be regulated at a temperature of about 1 to 150 degrees. 5. A crater surface forming portion of a bridge body integrally formed with a horizontal rod-shaped gas supply passage forming portion on the back side of a crater surface forming portion having a relatively thick plate shape, the crater surface forming portion being the center of the crater surface. At the top and bottom of the central crater portion arranged in the above, at least one each of the reinforcing rod axial center crater portions are arranged symmetrically in a row, and to the left and right of the central crater portion and each reinforcing rod axial crater portion, Reinforcing bar diameter corresponding craters are arranged in a line in a symmetrical manner, and between the central craters and adjacent craters for reinforcing bar diameter are arranged vertically and horizontally around each crater surface. An air supply groove is provided so as to communicate with the outer peripheral edge, and at least one or more guide recesses for drilling gas holes are provided on the crater surfaces of the central crater and the reinforcing bar diameter corresponding crater. For the forged piece to be the crater piece for gas pressure welding,
Each guide recess is provided with a gas hole reaching the gas supply passage forming portion at a predetermined angle, and a gas supply passage having a predetermined inner diameter is formed only from one end side or both ends of the gas supply passage forming portion. , The shape and dimensions of the gas pressure burner to be used on one side or both ends of the gas supply path in a plane where the angle with respect to the axis of the gas supply path passes through the approximate axis of the gas supply path and the central crater. About 13
A method for manufacturing a gas pressure welding crater piece, which comprises appropriately cutting a connecting portion of a gas supply pipe portion which is regulated within a range of about 5 to 150 degrees. 6. A crater surface forming portion of a bridge body integrally formed with a horizontal bar-shaped gas supply passage forming portion on the back side of a crater surface forming portion having a relatively thick plate shape, and the crater surface forming portion is at the center of the crater surface. At the top and bottom of the central crater portion arranged in the above, at least one each of the reinforcing rod axial center crater portions are arranged symmetrically in a row, and to the left and right of the central crater portion and each reinforcing rod axial crater portion, Reinforcing bar diameter corresponding craters are arranged in a line in a symmetrical manner, and between the central craters and adjacent craters for reinforcing bar diameter are arranged vertically and horizontally around each crater surface. An air supply groove is provided so as to communicate with the outer peripheral edge, and at least one or more guide recesses for drilling gas holes are provided on the crater surfaces of the central crater and the reinforcing bar diameter corresponding crater. On the other hand, the gas supply path forming part is formed on one end side in the axial direction. For the forging piece body as the gas pressure contact crater piece formed by bending the crater surface forming portion side by a predetermined angle, each guide recess has a gas hole reaching the gas supply path forming portion at a predetermined angle. Each of the gas supply passages is bored, and a gas supply passage having a predetermined inner diameter is formed only at one end or both ends of the gas supply passage forming portion, and the shaft of the gas supply passage is provided at one end or both ends of the gas supply passage. Gas supply that regulates the angle to the heart within a range of approximately 135 degrees to 150 degrees depending on the shape and size of the gas pressure welding burner to be used within a plane that passes through the gas supply path and the approximate axis of the central crater. A method for manufacturing a crater piece for gas pressure welding, which comprises appropriately cutting a connecting portion of a pipe portion. 7. A piece main body in which a horizontal bar-shaped gas supply passage forming portion is integrally formed on the back side of a relatively thick plate-like crater surface forming portion, and the crater surface forming portion is the center of the crater surface. At the top and bottom of the central crater portion arranged in the above, at least one each of the reinforcing rod axial center crater portions are arranged symmetrically in a row, and to the left and right of the central crater portion and each reinforcing rod axial crater portion, Reinforcing bar diameter corresponding craters are arranged in a line in a symmetrical manner, and between the central craters and adjacent craters for reinforcing bar diameter are arranged vertically and horizontally around each crater surface. An air supply groove is provided so as to communicate with the outer peripheral edge, and at least one or more guide recesses for drilling gas holes are provided on the crater surfaces of the central crater and the reinforcing bar diameter corresponding crater. On the other hand, the gas supply passage forming part is formed to have a crater surface One end side in the axial direction is bent and formed on the crater surface forming portion side by a predetermined angle, and a built-up portion is formed at a position near the crater surface forming portion on the other end side for gas pressure welding. With respect to the forging piece that is the crater piece, each guide recess is provided with a gas hole reaching the gas supply path forming portion at a predetermined angle, and a penetrating shape is formed only from one end side or both ends of the gas supply path forming portion. A gas supply passage having a predetermined inner diameter is drilled, and the gas supply passage is used at one end side of the gas supply passage in a plane whose angle to the axis of the gas supply passage passes through the gas supply passage and the substantial center of the central crater. Depending on the shape and dimensions of the burner for gas pressure welding, the connection part of the gas supply pipe part, which is regulated within the range of about 135 to 150 degrees, is appropriately cut, and at the other end side, inside the build-up part. Cut the connecting part of the reaching gas supply pipe part appropriately. Method for producing a gas pressure for the crater piece, characterized in that. 8. A gas having a predetermined inner diameter which is formed in each of the guide recesses so as to reach the gas supply passage forming portion at a predetermined angle and has a predetermined inner diameter only from one end side or both ends of the gas supply passage forming portion. For gas pressure welding to be used by drilling the supply passage and at one or both ends of the gas supply passage within the plane where the angle with respect to the axis of the gas supply passage passes through the gas supply passage and the central axis of the central crater. Depending on the shape and size of the burner, a plurality of gas pressure welding crater pieces formed by appropriately cutting the connecting portion of the gas supply pipe portion, which is regulated within a range of about 135 to 150 degrees, centering on the reinforcing bar to be pressure welded. All of the crater pieces for gas pressure welding are arranged at equal intervals along a circle drawn with the optimum separation distance radius for the pressure welding, and multiple gas supply pipes located outside the circle are connected. One blow tube installation A gas pressure welding burner using a gas pressure welding crater piece formed by using the forged piece according to any one of claims 1 to 4, wherein the burner is connected so as to communicate with the mouth. 9. A gas having a predetermined inner diameter which is formed in each of the guide recesses so as to reach the gas supply passage forming portion at a predetermined angle, and which is penetrated only from one end side or both ends of the gas supply passage forming portion. The gas supply passage is pierced, and at one end side of the gas supply passage, the angle with respect to the axis of the gas supply passage is within a plane that passes through the gas supply passage and the central axis of the central crater portion. Approximately 1 according to shape and size
The connection part of the gas supply pipe part that regulates within the range of 35 to 150 degrees is appropriately cut, and the other end side of the connection part of the gas supply pipe part that reaches the inside of the build-up part is formed if necessary. A plurality of gas pressure welding crater pieces that are appropriately cut are arranged at equal intervals along a circle drawn with the optimal separation distance radius centering on the rebar to be pressed, and outside the same circle. The forging piece body according to claim 3, wherein a plurality of gas supply pipe portions located are connected, and all of the gas pressure contact crater pieces are connected so as to communicate with one blower tube mounting opening. Burner for gas pressure welding using a crater piece for gas pressure welding.