JP2000317649A - Forged piece body used as nozzle piece for gas pressure welding, manufacture of nozzle piece for gas pressure welding using the forged piece body, and burner for gas pressure welding using the nozzle piece - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a forged piece body for a nozzle piece for gas pressure welding, which has a new structure by which a prescribed range including the butt pressure welding surface parts of reinforcing bars to be subjected to gas pressure welding and its vicinity, can be surely heated, a new manufacturing method for the nozzle piece for gas pressure welding using the forged piece body, and a burner for gas pressure welding, which uses the nozzle piece. SOLUTION: This forged piece body 2 is used as a nozzle piece for gas pressure welding, which is constituted as follows, nozzle parts 32, 32 for a reinforcing bar axial center position, are arranged on the upper and lower sides of a center nozzle part 31 arranged in the center by the nozzle surface forming part 3 of a piece main body forming a gas supply path forming part 4 on the backside of the nozzle surface forming part 3. On the left and right of the center nozzle part 31 and the nozzle parts 32, 32 for each reinforcing bar axial center, nozzle parts 33, 33 ... for corresponding to a reinforcing bar diameter are arranged respectively, and groove parts 34, 34 ... for air supply are provided, which have been arranged lengthwise and crosswise around each nozzle surface and have been formed so that the groove parts become communicating shapes up to the outer periphery edge of the piece main body, and on nozzle surfaces, guide recess parts 35, 35 ... for piercing a gas hole are provided.

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 for concentrically pressing and joining the ends of rebars, and more particularly to a butt press contact surface portion of a rebar to be subjected to gas pressure welding. A gas pressure welding crater piece having a novel structure that can surely heat a predetermined range including the vicinity thereof, a new method for manufacturing a gas pressure welding crater piece using the same, and a new method using the gas pressure welding crater piece It is an object of the present invention to provide a gas pressure welding burner having a structure.

[0002]

2. Description of the Related Art In the field of civil engineering and construction, most of steel bars for reinforced concrete are joined by a gas pressure welding method. In the gas pressure welding method, generally, ends of reinforcing bars are concentrically butted with each other. Pressurization and depressurization are repeated several times, and the joint is acetylene gas
By heating with a flame of an oxygen mixed gas and pressing simultaneously, two steel rods are combined and integrated into one.

[0003] In a general gas pressure welding method that has been performed, a method is used in which a ring burner that surrounds a joint portion in a ring shape and a pressure-welded portion of a reinforcing bar is appropriately and uniformly heated from all directions. As shown in the perspective view of the conventional ring burner in FIG. 12, the ring burner has a distal end branched into two parts at a blow pipe mounting port 6 connected to a blow pipe (not shown). A gas supply pipe part 5 curved to surround the outer peripheral side in an arc shape is provided, and a cylindrical crater tip 8 scattered along the circumferential direction is provided on an inner peripheral surface of the gas supply pipe part 5 on the arc-shaped tip side. , 8, ... are protruded, and each tip of the crater tips 8, 8, ... is directed radially toward the center of the arc shape, with the rebars 7, 7 subject to gas pressure welding as a center. In the case of pressure welding work, the gas pressure welding target iron The end faces 7 and 7 are coaxially butted against each other and pressed against each other with a predetermined pressure, and a combustion gas is supplied from a blow pipe mounting port 6 connected to a blow pipe (not shown). By radiating and burning gas from the tip, the joint end faces of the gas pressure welding rebars 7, 7 are heated, and the rebars 7, 7 are pressed while visually confirming the heating state of the rebars 7, 7.

In the conventional gas pressure welding operation, although the flame from the ring burner crater tips 8, 8,... Is configured to concentrate on the target rebar, each of the crater tips 8, 8,. .. Are formed so as to concentrate on the rebar because it is necessary to maintain a predetermined combustion temperature, and the entire flame of each crater tip 8, 8,... As the gas pressure welding work standard, the rebar is swiftly and uniformly within a certain time within a width range corresponding to at least the rebar diameter from the abutting surface because it is radiated to the rebar as a thin planar flame that Heat to about 1200 ° C. at the central temperature. ”
The ring burner itself should be at least equivalent to the diameter of the rebar on both sides (axial direction) of the rebar abutment surface, taking care not to change the distance from the rebar axis of each crater tip 8, 8, .... It is necessary to carry out an operation that requires extremely skill, such as performing parallel translation quickly by the width that is performed, and during the gas pressure welding operation, the pressure welding operator obtained by relying on his abundant experience and intuition until then The heating operation is continued while moving the ring burner on both sides of the gas pressure welding rebars 7, 7 in the axial direction with a quick and subtle sensation. While preventing heating,
The joint is surrounded by a reducing flame shield so that an oxide film is not formed at the joint of the reinforcing bars 7 and 7 to form a flat fractured surface, and a meticulous measure is taken to prevent unnecessary air from entering the joint. Difficult work operations are required to maintain optimal conditions, such as when care must be taken.

[0005] To solve the problems of securing human resources and work efficiency resulting from such highly specialized work contents, Japanese Unexamined Patent Publication No.
Various proposals have been made as disclosed in Japanese Patent Application Laid-Open No. 214343/1997 and Japanese Patent Application Laid-Open No. 9-271963. For example, Japanese Patent Application Laid-Open No. Hei 7-214343 discloses a method in which a coating material containing a deoxidizing agent or a dehydrogenating agent is applied to a joint end face of a steel bar to prevent formation of an oxide film at a joint. Also, in Japanese Patent Application Laid-Open No. 9-271963,
There has been proposed a gas pressure welding device capable of controlling a joint to follow a flame. However, none of these methods improve the ring burner itself and make the flame conditions advantageous, and the conventional ring burner is adopted by applying a coating agent to the reinforcing steel to be welded or by automating the welding work. It is intended to increase the precision and efficiency of the pressure welding operation, and has the disadvantage of increasing the material costs and equipment costs.

[0006] In view of the above-mentioned circumstances, even if a high level of skill is required as in the past, or even if expensive rebar materials or gas pressure welding devices are not employed, the rebars 7 and 7 subject to gas pressure welding can be used. In addition to being able to heat the joints uniformly and properly, the invasion of air into the joints creates an oxide film, causing flat fractures in the welded and welded parts, which can result in insufficient mechanical strength. As a person who has been involved in this industry for many years, he has been deeply interested in whether it can be eliminated, and has repeatedly researched and prototyped a new gas pressure welding burner that improved the performance of the part that is usually called the crater tip, It has reached the stage where it can be provided as a material that facilitates the crimping work and obtains good crimping performance, but its structure is more complex than the conventional ring burner. In this case, the production efficiency when producing various types of gas pressure welding burners corresponding to the diameters of the rebars 7 to be pressure welded is deteriorated, the number of manufacturing steps is increased, and the price rises. It had a new drawback.

The present invention has been undertaken for further development and research toward the practical use of a novel gas pressure welding burner capable of improving the productivity while ensuring good gas pressure welding performance, and has been conducting trial and error for a long time. After repeating many trial productions and experiments, we succeeded in realizing a gas pressure welding crater piece with a new structure that can eliminate those conventional problems, as shown in the drawings below. The configuration will be described in detail with some embodiments representative of the present invention.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS As clearly understood from the embodiments of the present invention shown in the drawings, the forged piece used as a cradle piece for gas pressure welding included in the present invention is basically as follows. Consists of a configuration. In other words, the crater face forming part of the piece main body in which the horizontal bar-shaped gas supply path forming part is integrally formed on the back side of the crater face forming part which has a relatively thick plate shape is arranged at the center of the crater face. At least 1 each above and below the central crater
The craters for the rebar axis center positions are arranged in a line and symmetrically arranged, and the craters for the rebar diameter are arranged symmetrically in a row on the left and right sides of the central crater and the craters for each rebar axis, respectively. In addition, between the adjacent crater portions at the central crater portion and the crater portion corresponding to the rebar diameter, an air supply groove portion arranged vertically and horizontally around each crater surface so as to communicate with the outer peripheral edge of the bridge body. Further, a crater piece for gas pressure welding configured such that at least one or more guide recesses for drilling gas holes are provided on each crater face of the central crater part and the crater part corresponding to the rebar diameter. It is a forged piece.

A more specific structure of the forged piece as the cradle piece for gas pressure welding having the basic structure is as follows.
A central crater in which a crater face forming part is arranged at the center of the crater face of a piece body formed by integrally forming a horizontal rod-shaped gas supply path forming part on the back side of a relatively thick plate-shaped crater face forming part. At the top and bottom of each part, at least one crater for each rebar axis position is arranged in a line in a symmetrical arrangement, and the center crater part and the left and right crater parts for each rebar axis are respectively provided for the rebar diameter corresponding. The craters are arranged symmetrically in a row, and between the adjacent craters at the central crater and the rebar-diameter corresponding crater, they are arranged vertically and horizontally around each crater face and communicate with the outer periphery of the bridge body. In addition, at least one or more guide recesses for drilling gas holes are provided on each of the crater surfaces of the central crater portion and the crater portion corresponding to the reinforcing bar diameter. The gas supply path forming part has one end side in the axial center direction, The forged piece body to the gas pressure for the crater piece to gist configuration shall become formed predetermined angle bent section side.

[0010] More specifically, the crater face forming portion of the piece body, in which a horizontal rod-shaped gas supply path forming portion is integrally formed on the back side of the crater face forming portion having a relatively thick plate shape. At least one crater portion for each rebar axis position is arranged in a line in a symmetrical arrangement above and below a central crater portion arranged at the center of the crater surface, and the central crater portion and each rebar axis are arranged. On the left and right sides of the crater, the craters for the rebar diameter are arranged in a line and symmetrically, and between the adjacent craters at the center crater and the crater for the rebar diameter, around each crater face. Air supply grooves are provided vertically and horizontally so as to communicate with the outer peripheral edge of the bridge body, and at least one or more gas holes are formed in each of the crater surfaces of the central crater and the rebar diaper corresponding crater. It has a crater surface provided with a guide recess for installation. On the other hand, the gas supply path forming portion is formed such that one end in the axial direction is bent at a predetermined angle toward the crater surface forming portion, and the portion adjacent to the crater surface forming portion on the other end side is overlaid. It can be said that the forged piece body is a crater piece for gas pressure welding whose configuration is formed as a gist.

The bridge body serves to form the body of the cradle piece for gas pressure welding, and the crater face forming part and the gas supply path forming part must be integrally formed. Formed airtight by casting, etc.
Unless drilling is performed, it is formed in a dense ingot shape that does not allow gas to pass through, and post-processing by cutting only the gas holes at each crater and the connection parts of the gas supply pipes that require a certain degree of accuracy is required. It should be constructed in such a way that it can be manufactured, and considering the production efficiency, it is most desirable to manufacture by cold forging materials such as brass, copper, bronze, ultra mild steel, carbon steel, soft stainless steel, aluminum and magnesium alloy. Depending on the material to be manufactured and the manufacturing conditions, it can be manufactured based on a casting or sintering technique, or it can be injection-molded from a nonmetallic material having heat resistance.

[0012] The crater face forming portion serves to form a center crater, a crater for the rebar shaft center position, a crater for the rebar diameter, and a function of forming a gas supply groove. It must be formed integrally with the part, has sufficient heat resistance to flames, and free cutting that enables good cutting so that gas holes can be easily drilled It is desirable to form from the material which has.

The central crater portion is formed substantially at the center of the crater surface forming portion, and has a function of enabling gas holes to be formed. The protruding end surface has a guide recess for forming gas holes. The crater for the rebar shaft center position is located above and below the center crater, allowing the formation of gas holes located parallel to the axis of the rebar to be welded during the welding operation. As in the case of the central crater, a guide recess for gas hole drilling should be formed on the protruding end surface as in the case of the central crater. It has a function of forming one or a plurality of appropriately spaced gas holes that are positioned substantially orthogonal to the axis of the rebar to be press-welded during the press-welding operation. An auxiliary crater outside each crater as long as the supply gas pressure is not reduced Form it is also possible to.

The guide recess has a function of displaying the drilling position of the gas hole and of accurately guiding the tip of the cutting tool when drilling the gas hole. The guide recess has a diameter and depth sufficient to guide the tool tip. It is desirable to set it to a hole shape such as a spherical shape, a conical shape, a polygonal pyramid shape or a cylindrical shape so that the cut by the tool is not alienated, and in consideration of productivity, when forging a forged piece, It is preferable to carry out embossing simultaneously.
In addition, the air supply groove serves to allow the surrounding fresh air to flow toward each crater, and the central crater, the crater for the rebar shaft center position, and the crater for the rebar diameter. It should be a groove shape formed between each crater part adjacent to each other, and it is desirable to form it by a combination of a plane linear shape that does not hinder the flow of air, or a gentle planar curve shape, and it is easy to form by forging Thus, it is preferable that the groove shape be an expanded cross section having a slight draft.

Further, in the forged piece body, the connecting portion to the gas supply pipe section provided at one end or both ends of the gas supply path of the piece body has an angle of its axis with respect to the axis of the gas supply path. If the angle is regulated to about 135 to 150 degrees in the plane passing through the gas supply path and the substantially central axis of the central crater, it is extremely convenient for forming a crater piece corresponding to the shape and dimensions of the gas pressure welding burner. Can be good.

[0016]

[Related invention 1] In connection with the above-described forged piece serving as a cradle piece for gas pressure welding, the present invention relates to a method for producing a crater piece for gas pressure welding using the forged piece. The gist of the configuration is that the crater face formation of the piece body formed by integrally forming the horizontal rod-shaped gas supply path forming part on the back side of the relatively thick plate-shaped crater face formation part At least one crater portion for each rebar axis position is arranged in a line in a symmetrical arrangement above and below a central crater portion arranged at the center of the crater surface, and the central crater portion and each rebar axis are arranged. On the left and right sides of the crater, the craters for the rebar diameter are arranged in a line and symmetrically, and between the adjacent craters at the center crater and the crater for the rebar diameter, around each crater face. An air supply groove that is arranged vertically and horizontally and communicates with the Further, on each crater surface of the central crater part and the crater part corresponding to the rebar diameter, a forged piece which is a gas pressure welding crater piece provided with at least one or more guide recesses for drilling gas holes, In each of the guide recesses, a gas hole reaching the gas supply path forming section at a predetermined angle is formed, and a gas supply path having a predetermined inner diameter is formed only at one end of the gas supply path forming section or at both ends. At one end or both ends of the gas supply path, the angle with respect to the axis of the gas supply path is within the plane passing through the gas supply path and the central axis of the central crater, and the shape and dimensions of the gas pressure welding burner to be used. The basic configuration is to appropriately cut a connection portion of the gas supply pipe portion which is restricted to a range of about 135 to 150 degrees according to the above.

If the method of manufacturing a cradle piece for gas pressure welding included in the present invention is described as a more specific structure, a horizontal rod-shaped gas supply is provided on the back side of a relatively thick plate-shaped crater surface forming portion. The crater face forming part of the bridge body formed integrally with the road forming part has at least one crater part for rebar axis center position arranged in a line above and below a central crater part arranged in the center of the crater face. In addition to the central crater and the crater for each rebar axis, the craters for the rebar diameter are arranged in a line in a symmetrical arrangement on the left and right, respectively. Between the adjacent crater portions at the crater portion, there are provided air supply grooves arranged vertically and horizontally around each crater surface so as to communicate with the outer peripheral edge of the piece body, and further for the central crater portion and the rebar diameter correspondence Each crater face of the crater should have at least one gas On the other hand, the gas supply path forming part is formed by bending one end of the gas supply path forming part in the axial direction at a predetermined angle to the crater face forming part side. For the forged piece body to be the crater piece,
In each of the guide recesses, a gas hole reaching the gas supply path forming section at a predetermined angle is formed, and a gas supply path having a predetermined inner diameter is formed only at one end of the gas supply path forming section or at both ends. At one or both ends of the gas supply path, the angle with respect to the axis of the gas supply path is within the plane passing through the gas supply path and the substantially central axis of the central crater, and the shape and dimensions of the gas pressure welding burner to be used. About 13 according to
It can be said that a method of manufacturing a cradle piece for gas pressure welding has a configuration in which a connection portion of a gas supply pipe portion that is restricted to a range of about 5 degrees to 150 degrees is appropriately cut.

According to a more specific configuration, a crater surface forming part of a piece body in which a horizontal bar-shaped gas supply path forming part is integrally formed on the back side of a relatively thick plate-shaped crater surface forming part. At least one crater portion for each rebar axis position is arranged in a line in a symmetrical arrangement above and below a central crater portion arranged at the center of the crater surface, and the central crater portion and each rebar axis are arranged. On the left and right sides of the crater, the craters for the rebar diameter are arranged in a line and symmetrically, and between the adjacent craters at the center crater and the crater for the rebar diameter, around each crater face. Air supply grooves are provided vertically and horizontally so as to communicate with the outer peripheral edge of the bridge body, and at least one or more gas holes are formed in each of the crater surfaces of the central crater and the rebar diaper corresponding crater. With a crater surface with a guide recess for installation On the other hand, the gas supply path forming portion has one end in the axial direction bent at a predetermined angle on the crater surface forming portion side, and at a position adjacent to the crater surface forming portion on the other end side, In the forged piece body serving as a crater piece for gas pressure welding formed with a built-up part, a gas hole reaching the gas supply path forming part at a predetermined angle is formed in each guide recess, and the gas supply path forming part is formed. Perforating a gas supply passage of a predetermined inner diameter that is penetrated only from one end or at both ends,
At one end of the gas supply path, the angle with respect to the axis of the gas supply path depends on the shape and dimensions of the gas pressure welding burner used in a plane passing through the gas supply path and the substantially axis of the central crater. The connecting portion of the gas supply pipe portion, which is restricted to a range of about 135 to 150 degrees, is appropriately cut, and the connecting portion of the gas supply pipe portion reaching the inside of the buildup portion is appropriately cut at the other end side. A method of manufacturing a crater for gas pressure welding, which has a configuration adapted to be processed.

The order of the step of piercing the gas hole and the step of piercing the gas supply passage in the forged piece may be performed in any order. It is also possible to punch and pierce the gas supply path during the process. In addition, the order of the step of piercing the gas supply path and the step of cutting the connection part of the gas supply pipe section is also different. Even so, the same desired structure can be obtained. Further, the drilling angle of the gas hole is such that the center crater is pierced so as to be substantially perpendicular to the axis of the rebar to be pressed, and the other craters located around the center crater emit combustion gas around the center crater. The holes may be perforated so that each is 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 forged piece serving as a crater for gas pressure welding which forms a skeleton of the present invention, and a method for manufacturing a crater for gas pressure welding using the forged piece described above. A gas pressure welding burner using a gas pressure welding cradle piece having the following configuration, which is manufactured by the method of manufacturing the forged piece and the gas pressure welding crater piece, is also included as a related invention. That is, in each of the guide recesses, a gas hole reaching the gas supply path forming section at a predetermined angle is formed, and a gas supply path having a predetermined inner diameter that is penetrated only from one end of the gas supply path forming section or both ends. The shape of the gas pressure welding burner used in the plane where the angle with respect to the axis of the gas supply path is formed at one end or both ends of the gas supply path and the gas supply path and the central crater substantially pass through the axis. A plurality of crater pieces for gas pressure welding formed by appropriately cutting the connection portion of the gas supply pipe portion, which is restricted to a range of about 135 ° to 150 ° depending on the size, for pressure welding centering on the rebar to be welded. Along with the circle drawn at the optimum separation distance radius, they are arranged at equal intervals from each other, and a plurality of gas supply pipes located outside the circle are connected, and all the gas pressure welding crater pieces are one. Connect to the blow pipe installation port The connection was made by structure to a gas pressure for burners to the basic.

More specifically, a gas hole reaching the gas supply path forming portion is formed in each guide recess at a predetermined angle, and a through hole is formed only at one end of the gas supply path forming portion or at both ends. A gas supply path having a predetermined inner diameter is drilled, and an angle with respect to the axis of the gas supply path is used at one end of the gas supply path in a plane passing through the gas supply path and the substantially central axis of the central crater. Depending on the shape and dimensions of the gas pressure welding burner, the connecting portion of the gas supply pipe portion that is regulated to be within a range of about 135 to 150 degrees is appropriately cut, and the other end side is provided with a meat as necessary. A plurality of crater pieces for gas pressure welding formed by appropriately cutting the connection part of the gas supply pipe part reaching the inside of the protruding part are equal to each other along a circle drawn with the radius of separation distance optimal for pressure welding centering on the rebar to be welded. When placed at an interval, A gas pressure welding system having a configuration in which a plurality of gas supply pipe portions located outside the same circle are connected, and all gas pressure welding crater pieces are connected so as to communicate with one blow pipe installation port. It can also be said that it is a burner.

The gas pressure welding burners use a minimum of two gas pressure welding crater pieces, and face each other so as to sandwich the rebars to be welded at a predetermined distance on the crater surfaces, and are connected by gas supply pipes. In addition to being able to be formed, it is also possible to arrange a total of three gas pressure welding crater pieces at each vertex of a plane regular triangle with the welding target reinforcing bar as a center, and to connect each with a gas supply pipe, A gas supply pipe portion is inserted and connected to reach the inside of the cladding portion by using a cladding portion formed at a location close to the crater face forming portion on the other end side of the gas supply passage forming portion; It is also possible to adopt a structure that avoids extreme curvature of the part.

The gas supply pipe section has a function of connecting the crater piece for gas pressure welding and the blow pipe mounting port with sufficient strength and a function of supplying combustion gas from the blow pipe mounting port to each piece body. Therefore, the gas pressure welding burner must be formed to have the strength to maintain the shape and the tightness to secure the airtightness of the combustion gas flowing inside, and to form the gas pressure welding crater piece. The structure should be such that overheating by flame can be avoided as much as possible.
In addition to being formed from 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. It may be formed so as to be bent to the opposite side of the forming portion to avoid the flame and to be disposed at a sufficient distance from the reinforcing steel bar to be pressed at the time of pressing.

The blow pipe installation port is provided with a combustion gas valve, an oxygen valve,
And a function of connecting the gas supply pipe to the blowpipe having a gripping pipe and the like, and a function of distributing and supplying the combustion gas supplied from the blowpipe to the gas supply pipe. It is important 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 be connected to the blowpipe by a screw connection or the like that can ensure high airtightness. In the following, the structure of the present invention will be described in detail, together with the embodiment shown in the drawings.

[0025]

EXAMPLE 1 FIG. 1 is a plan view of a forged piece used as a cradle piece for gas pressure welding, FIG. 2 is a side view of the forged piece shown in FIG. 1, and FIG. The case shown in each of the front views as viewed from above is a gas pressure welding included in the present invention which has a basic configuration in which a crater face forming part and a gas supply path forming part are integrally formed by cold pressing. 1 shows a typical example of a forged piece used as a crater piece.

The forged piece 2 is formed by integrally forming a crater face forming part 3 and a gas supply path forming part 4 by cold-pressing a bar made of brass. A central crater portion 31 is formed at the center thereof, and crater portions 32, 32 for reinforcing bar axial position are formed on the upper and lower sides of the central crater portion 31, respectively. , 32 are arranged and formed on the left and right sides of the reinforcing bar diameter corresponding crater portions 33, 33,... The craters 32, 32,... Are formed vertically and horizontally around each crater face, and are provided with a predetermined width and a predetermined depth which are communicated to the outer peripheral edge of the bridge body. The grooves 34, 34,... Are formed so as to expand toward the surface of the crater surface forming portion 3. It is further central crater portion 3
1. Each of the crater portions 32, 32 for the rebar shaft center position and the crater portions 33, 33,... Corresponding to the rebar diameter is formed into a substantially spherical shape for drilling gas holes at positions spaced at predetermined intervals. .. Are formed.

The gas supply path forming section 4 has one end in the axial direction directed toward the crater forming surface section 31 and a plane passing through the gas supply path 42 formed by post-processing and substantially the center of the central crater section 31. And is formed to be bent at an angle A of about 135 degrees to about 150 degrees, and protrudes toward the crater forming surface portion 31 at a position close to the crater forming surface portion 31 on the other end side. A built-up portion 41 is formed.

[0028]

Embodiment 2 A plan view of a gas pressure welding burner shown in FIG. 4 shows an embodiment included in a gas pressure welding burner using a gas pressure welding crater piece of the present invention. The connecting portion 43 of the gas supply pipe portion 5 provided at one end of the supply passage 44 is connected to the gas supply passage about 13
The two forged pieces 2, 2 bent and formed at an angle of 5 degrees,
It is connected to one blow pipe installation port 6.

The gas pressure welding burner 1 is provided with a forged piece body as shown in FIG. 1 to FIG. Each crater part 31, 32, 3 on the surface of the crater face forming part 3 of 2
A gas hole reaching the gas supply path 44 from 2, 33, 33,... Is formed, and a gas supply path 44 is formed from the other end surface of the gas supply path forming portion 4 where the gas supply path forming portion 4 is not bent. A lid prepared in advance is connected to the opening formed by the perforation on the other end side and closed, and the angle of the gas supply path forming unit 4 with respect to the axis of the gas supply path 44 is adjusted by the gas supply path 44.
And a connecting portion 43 for connecting the end of the gas supply pipe portion 5 to one end of the gas supply passage forming portion 4 bent at an angle of about 135 degrees in a plane passing through the substantially central axis of the central crater portion 31. The gas pressure welding crater pieces 2, 2 formed by cutting are connected and integrated by welding, brazing, screw connection, or the like.
Are sandwiched at a suitable interval for gas pressure contact, and are arranged to face each other.

The crater piece 2 for gas pressure welding has a central crater 3
1 are bored so as to be substantially perpendicular to the center of the rebar 7 to be press-welded at the time of gas pressure welding. When the gas holes of the central crater 33 are each set to 0 degree, the gas holes of 3 to 23 degrees are directed outward as shown by the chain line arrows in FIG. Drilled in a state of being radially inclined, the degree of inclination is selectable perforation angle over the range shown by the chain line in FIG. 3, the axis of the gas hole, In addition to the hole being formed so as to be directed toward the center of the gas supply path 44, the gas supply path 44 may be formed so as to open tangentially on the peripheral surface side of the gas supply path 44.

[0031]

Embodiment 3 In the example shown in the plan view of a gas pressure welding burner using three gas pressure welding crater pieces shown in FIG. 5, three gas pressure welding crater pieces 2 ', 2', 2 'are suitable. And the gas supply passage 44 is bent at one end of the gas supply pipes 6 and 6 attached in a plane V-shape with respect to the blow pipe attachment port 6. One end side is kept closed, and the gas pressure welding cradle piece 2 ′ obtained by cutting the concentric connection portion 43 is connected to the other end side substantially concentrically,
At the tip of the other gas supply pipe 6, a gas pressure welding crater piece 2 'is formed by connecting the other end of the gas supply path 44, which is not bent, concentrically. A base end of a gas supply pipe part 5 bent in a substantially L-shape in a plane is connected to one end side of the cradle piece 2 ′ bent at about 135 degrees so as to surround the reinforcing steel bar 7 to be pressed during pressing. The tip of the L-shaped gas supply pipe 5 is connected to a crater 2 'for gas pressure welding, the other end of which is bent and the other end of which is closed, for a total of three gas pressure welding pieces. Crater pieces 2 ', 2',
Each of 2 ′ is configured such that the optimum distance for gas pressure welding is separated from the welding target reinforcing bar 7 at the time of gas pressure welding and that they are arranged at the vertices of a plane regular triangle.

[0032]

Embodiment 4 FIG. 6 shows a plan view of a gas pressure welding burner using four gas pressure welding crater pieces, which is shown in the plan view of four gas pressure welding crater pieces 2 ', 2',... 1 shows a configuration of a typical gas pressure welding burner 1 having two straight gas supply pipe portions 5, 5 extending in a plane V shape from a blow pipe mounting port 6. One end of each of the gas pressure welding crater pieces 2 ', 2' formed by penetrating both ends of the gas supply passages 44, 44 is connected to each of the leading ends of the gas supply paths 44, 44, respectively. On the end side, a gas supply pipe part 5, which is bent at an angle of about 150 degrees, with the central part in the longitudinal direction of the axial center directed toward the rebar 7 to be pressed during gas pressing.
5 are connected to the gas supply pipes 5, 5, and
Are connected to one end of gas pressure welding crater pieces 2 ', 2 whose other ends are closed, and a total of four gas pressure welding crater pieces 2', 2 ',. Crater pieces 31 ', 31' which are arranged at the apical positions of a regular square centered on the reinforcing bar 7 to be welded, and which face the cradle pieces 2 ', 2' facing each other.
Are positioned diagonally.

[0033]

Fifth Embodiment A gas pressure welding burner shown in the last FIG. 7 is also an example in which four gas pressure welding crater pieces are used similarly to the above embodiment. ... shows another configuration of the gas pressure welding burner 1 having the gas pressure welding crater pieces 2 ', 2',..., And a total of four gas pressure welding crater pieces 2 ', 2',. The positions of the gas supply pipes 5 and the shapes and structures of the gas supply pipes 5 and 5 connecting them to each other are basically the same as those shown in the fourth embodiment. The distance between the gas supply pipes 5, 5 connected to the left and right gas pressure welding crater pieces 2 ', 2' is curved and extended so that they are set to be larger than the outer diameter of the reinforcing bar 7 to be pressure welded. It has become something.

The gas supply pipe portions 5, 5 extending from the blow pipe attachment port 6 have portions, which are separated by a distance larger than the outer diameter of the rebar 7 to be pressed, substantially the same as the outer diameter of the rebar 7 to be pressed. Or, they extend in a parallel manner over a longer range, and the other ends of the gas pressure welding crater pieces 2 ′, 2 ′ are connected to their respective tips, so that a stronger connection can be achieved. In the case of obtaining the crater pieces 2 'for gas pressure welding, a build-up part 41 is formed near the crater face forming part 3 on the other end side as shown in FIG. The gas supply pipe section 5 can be configured to be connected to a state shown by a two-dot chain line in FIG.

[0035]

The forged 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 sectional side view of the forged piece 2 in FIG. As shown in the side view of the connection example of the gas supply pipe section in FIG. 9, the connection section 43 that connects the gas supply pipe section 5 to the end of the gas supply path 44 is cut. The gas supply passage 44 is formed as a crater piece 2 'for gas pressure welding. 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, In a plane passing through the substantially central axis of the central crater portion 31, a connecting portion 43 restricted to an angle A of about 135 degrees is formed, and is shown in a side view of another connection example of the gas supply pipe portion in FIG. like,
The angle with respect to the gas supply passage 44 is approximately 150 in a plane passing through the gas supply passage 44 and the substantially central axis of the central crater 31.
It is also possible to use the connecting portion 43 regulated to the degree angle B.

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 two-dot chain line in FIG. Supply pipe section 5
Can be connected to each other. Further, as shown in FIG.
Each of the gas holes 2, 33, 33,... Can be bored toward the center of the gas supply passage 44, and besides, pierced to the tangential range on the inner peripheral wall surface of the gas supply passage 44. It is possible to set a proper angle in accordance with the diameter of the rebar 7 to be press-welded and perform the drilling.

The gas pressure welding burner 1 shown in FIG. 4 connects the blow pipe mounting port 6 to a blow pipe having a combustion gas valve, an oxygen valve, a gripping pipe, and the like. The combustion gas released from the hole burns and emits a flame, and a pair of opposed gas pressure welding cradle pieces 2 ′, 2 ′ are separated from each other by a distance suitable for gas pressure welding between the crater surfaces 3. Then, a flame is blown so as to sandwich the rebar 7 to be welded and spread over the entire peripheral wall surface of the rebar 7 to be welded as indicated by a chain line arrow in the figure, thereby uniformly heating the joint of the rebar 7 to be welded.

The gas pressure welding burner 1 shown in FIG. 5 has three gas pressure welding crater pieces 2 ', 2', 2 'which are arranged in a plane so as to be located at each vertex of an equilateral triangle centered on the reinforcing bar 7 to be pressed.
From each of the above, the flame is uniformly sprayed on the entire peripheral wall surface of the rebar 7 to be pressed and uniformly heated, and all the gas supply pipes 5, 5, 5 are provided as necessary to avoid the flame. Since it is bent and formed, the flame is not directly blown by the flame, and the durability and life of the gas pressure welding burner 1 are improved.

The gas pressure welding burner 1 shown in FIG.
The middle part of the gas supply pipes 5, 5 connecting the two left and right crater pieces 2 ', 2' for gas pressure welding is
Are bent so as to protrude toward the opposite side to 3,..., And are configured to be separated from the rebar 7 to be press-welded by a predetermined distance during the press-welding operation, so that the gas supply pipes 5, 5 are damaged by overheating. It is to prevent. Like the gas supply pipes 5 and 5 shown in the plan view of the gas pressure welding burner 1 having an undesired structure in FIG. 11, the gas pressure welding burner 1 enters the inside of the optimum departure radius R from the crater face 3 to the reinforcing steel 7 to be pressed. That can be avoided.

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

[0041]

As described above, according to the forged piece used as the cradle piece for gas pressure welding of the present invention, the crater piece individually designed for each diameter of the rebar to be welded can be cut from the first time. It is necessary to manufacture the gas pressure welding burner for a long period of time, increasing the manufacturing cost. The lead time from shipment to shipment was long and tended to be expensive, but all such problems were solved and almost all the diameters of commonly used rebars were made the same shape. Using pre-manufactured forged pieces, gas supply passages and gas holes are drilled later according to the rebar diameter to be pressed and completed, so the number of parts required for inventory is significantly reduced. It is possible to do 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 forged piece body are connected to the gas supply pipe according to the diameter of the reinforcing bar to be pressed, the gas hole drilling angle, or the gas pressure welding burner. Since it is formed in a structure that can sufficiently respond to the connection angle etc. of the gas supply pipe part according to the crater arrangement structure, the connection angle of the gas supply pipe part according to the rebar diameter to be pressed As long as the drilling angle of the gas hole or the connection angle of the gas supply pipe part according to the crater arrangement structure is set to the optimum one and drilling is performed, various applications can be produced accurately and in large quantities, and It is possible to provide a gas pressure welding cradle piece with an almost ideal structure that can radiate flames over a wide range that could not be obtained with conventional nozzles, and it is very powerful in the production of gas delivery craters with short delivery time and low cost To demonstrate So that the point can be obtained.

Further, in the method of manufacturing a crater piece for gas pressure welding using this forged piece, all the crater pieces for gas pressure welding connected between the gas supply pipes or at the ends thereof are formed from a forged piece having the same shape. It can be manufactured, so that molding dies, machine tools, jigs and tools can be shared, and multiple types of crater pieces for gas pressure welding can be manufactured collectively by one setup using the same machine equipment The connection angle of the gas supply pipe to the cradle piece for gas pressure welding can be realized with an optimal connection structure that takes into account the direction and fog of the flame. Piping that avoids the gas supply pipe as much as possible is easy, and the connection structure of the gas supply pipe at the optimum angle can be realized by simply performing a slight cutting process on the required part of the forged piece, Therefore, the product Man-hours and manufacturing costs are greatly reduced, improving production efficiency and exhibiting the excellent feature of being able to manufacture high-performance gas pressure welding craters with higher gas pressure welding performance than conventional products. Become.

Further, according to the gas pressure welding burner using the gas pressure welding crater piece of the present invention, the angle with respect to the axis of the gas supply path is set at one end or both ends of the gas supply path.
In the plane passing through the gas supply path and the substantially central axis of the central crater part, a cradle piece for gas pressure welding is used in which a connection part of a gas supply pipe part which is restricted to a range of about 135 to 150 degrees is appropriately cut. In this way, it is possible to easily realize gas pressure welding burners with shapes and dimensions corresponding to various diameters of the rebar to be welded, and efficiently produce many types of gas pressure welding burners even in small quantities. It is possible to manufacture and provide gas pressure welding burners with the optimal structure for gas pressure welding the rebar to be welded of various diameters, regardless of the demand, regardless of the size of the demand. An excellent effect that the entire joint portion of the rebar to be pressed can be surrounded by a uniform and stable flame and heated under favorable conditions can be exhibited.

In particular, the forged piece 2 taken up in the first embodiment
Are formed in the crater face forming portion 3 by cold pressing in advance, and the guide concave portions 35, 35,. It is possible to boring the concave portion as a guide, eliminating the need for forming a pilot hole, and further appropriately setting the number and position of gas holes and the direction of the axis,
A plurality of types of crater pieces for gas pressure welding can be easily manufactured, and one end of the gas supply passage 44 is bent toward the crater surface forming part 3 so as to be optimally oriented. The gas supply path 44 can be perforated, and the gas supply pipe part 5 is connected to the crater face forming part 3 in a bent state by using the built-up part 41 on the other end side. It is designed to enable the manufacture of crater pieces 2 'corresponding to various burners for gas pressure welding. It is ideally prepared by stocking the forged pieces 2 as they are and performing perforation processing as necessary. This makes it possible to produce a crater piece 2 'and to realize a gas pressure welding burner having an optimum structure corresponding to the reinforcing bar to be pressed.

Gas pressure welding burner 1 shown in Example 2
Are scattered over substantially the entire surface of the crater surface forming portion 3, despite being manufactured using only two crater pieces 2 ', 2'. , 33, 33,... And the respective drilling angles are regulated in accordance with the thickness and the separation distance of the rebar 7 to be press-welded. Combustion gas is released almost uniformly without waste, and only two cradle pieces 2 ', 2' are used, and more crater pieces 2 ', 2',. In comparison with the above, the handling of positioning the reinforcing bar 7 at the center position is much easier, and the center swing can be minimized even in the parallel movement operation. Reinforcing bar 7 has a great advantage of facilitating uniform heating of a predetermined area. The reflection of the flame from the outer periphery of the reinforcing bar 7 also does not directly go to the gas supply pipes 5 and 5 as shown by the arrows in the figure, eliminating damage due to overheating and finally improving the durability of the burner 1. The effect of increasing is obtained.

Also, as in the gas pressure welding burners 1 of the third and fourth embodiments, three or more crater pieces 2 ',
A gas pressure welding burner 1 having a typical structure consisting of 2 ',... Can be formed by employing a crater piece 2' formed by using a forged piece body 2 of exactly the same shape of the present invention. In addition, the arrangement of the gas supply pipes 5, 5, ... is located outside the imaginary circle drawn so as to be in contact with the crater surface forming parts 3, 3, .... The gas pressure welding burner 1 can be realized, and the durable gas pressure welding burner 1 can be realized by preventing overheating and deterioration of the gas supply pipes 5, 5,... Accordingly, the gas pressure welding burner 1 of extremely economical and high performance can be obtained.

Although not shown, in the gas pressure welding burner 1 using four crater pieces 2 ', 2',..., Each pair of crater pieces 2 ', The separation distance of 2 'is set closer than that shown in Fig. 6 (therefore, the arrangement of the central crater portions 31, 31 between the facing cradle pieces 2', 2 'facing each other is not located diagonally. ), The rebar 7 to be pressed against the flame radiated from each crater piece 2 ', 2', ...
The rebound from the outer peripheral surface can be directed in a direction slightly away from the gas supply pipes 5, 5,...
Further, the advantage that the durability can be increased can be obtained.

Further, the four crater pieces 2 ',
In the gas pressure welding burner 1 according to another embodiment using 2 ',..., The flame is bent toward the outside in the middle of the left and right gas supply pipes 5 and 5, so that the flame is released. ,
In this case, it is possible to prevent the spraying of the gas directly onto the nozzle 5 and prevent the loss of the material, thereby realizing a safe pressure welding operation. Further, the gas pressure welding burner 1 shown in Example 5 is extended from the blow pipe mounting opening 6. Even if the pair of left and right gas supply pipes 5, 5 is not extremely bent, the separation distance from each other can be set to be larger than the diameter D of the rebar 7 to be press-welded. Since it can be operated so as to move the rebar 7 to be pressed between the supply pipe portions 5 and 5, it can be provided as the gas pressure burner 1 which is highly evaluated by skilled workers.

As described above, the forged piece used as the cradle piece for gas pressure welding of the present invention, the method for manufacturing the crater piece for gas pressure welding using the same, and the burner for gas pressure welding using the cradle piece for gas pressure welding are as follows: The new configuration makes it possible to achieve the intended purpose uniformly, and it is particularly easy to manufacture, making it much more economical than the traditional unit price of crater pieces. In the harsh economic environment, the work efficiency itself is greatly increased, and it is possible to reliably reduce costs and shorten the time required for manufacturing, thereby ensuring a stable product supply. In the construction industry, which is required to respond accurately and promptly to various demands in the field, it has been highly evaluated as being able to carry out high-precision and economical gas pressure welding work in response to the times, and it has been widely evaluated. hand Use, is expected to continue to spread.

[Brief description of the drawings]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows several embodiments of a forged piece representative of the present invention, a crater for gas pressure welding using the same, and a burner for gas pressure welding.

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

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

FIG. 3 is a front view showing a state where the forged piece is viewed from a built-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 gas pressure welding burner using four forged pieces.

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

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

FIG. 10 is a side view showing another example of the cutting process of the forged piece in a vertical section.

FIG. 11 is a side view showing a further example of a cutting process of a forged piece in a vertical section.

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

[Explanation of symbols]

 Reference Signs List 1 Burner for gas pressure welding 2 Forged piece (crater piece for gas pressure welding) 2 'Crater piece formed using forged piece 3 Crater surface forming part 31 Central crater part 32 Crater part for rebar axis center position 33 Rebar Diameter crater part 34 Same air supply groove part 35 Same guide concave part 36 Same gas hole 4 Gas supply path forming part 41 Same built-up part 42 Same gas supply path 43 Same connection part (gas supply pipe part) 44 Same gas supply path 5 Gas supply pipe section 6 Blow pipe installation port 7 Rebar to be welded D Same diameter R Radius of separation from crater face to rebar to be welded

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI theme coat ゛ (Reference) F23D 14/58 F23D 14/58 B

Claims (9)

[Claims] 1. A crater face forming part of a piece body in which a horizontal rod-shaped gas supply path forming part is integrally formed on the back side of a relatively thick plate-shaped crater face forming part, the crater face forming part is located at the center of the crater face. At the top and bottom of the central crater portion, at least one each of the reinforcing bar axial position crater portions is arranged in a line and symmetrically, and on the left and right sides of the central crater portion and each reinforcing bar crater portion, The craters corresponding to the rebar diameter are arranged in a line in a symmetrical manner, and the center crater and the adjacent craters for the rebar diameter are arranged vertically and horizontally around each crater face, and the piece body An air supply groove is provided so as to be in communication with the outer peripheral edge, and at least one or more guide recesses for drilling gas holes are provided on each of the crater surfaces of the central crater portion and the crater portion corresponding to the rebar diameter. A forged piece used as a crater for gas pressure welding. 2. A crater face forming portion of a piece body in which a horizontal rod-shaped gas supply path forming portion is integrally formed on the back side of a relatively thick plate-shaped crater face forming portion, the crater face forming portion is located at the center of the crater face. At the top and bottom of the central crater portion, at least one each of the reinforcing bar axial position crater portions is arranged in a line and symmetrically, and on the left and right sides of the central crater portion and each reinforcing bar crater portion, The craters corresponding to the rebar diameter are arranged in a line in a symmetrical manner, and the center crater and the adjacent craters for the rebar diameter are arranged vertically and horizontally around each crater face, and the piece body An air supply groove is provided so as to be in communication with the outer peripheral edge, and at least one or more guide recesses for drilling gas holes are provided on each of the crater surfaces of the central crater portion and the crater portion corresponding to the rebar diameter. On the other hand, the gas supply path forming portion has one end in the axial direction, A forged piece serving as a crater for gas pressure welding, wherein the forged piece is formed by bending a predetermined angle on the side of the crater face forming portion. 3. A crater face forming portion of a piece body in which a bar-shaped gas supply path forming portion is integrally formed on the back side of a relatively thick plate-shaped crater face forming portion, wherein the crater face forming portion is in the center of the crater face. At the top and bottom of the central crater portion, at least one each of the reinforcing bar axial position crater portions is arranged in a line and symmetrically, and on the left and right sides of the central crater portion and each reinforcing bar crater portion, The craters corresponding to the rebar diameter are arranged in a line in a symmetrical manner, and the center crater and the adjacent craters for the rebar diameter are arranged vertically and horizontally around each crater face, and the piece body An air supply groove is provided so as to be in communication with the outer peripheral edge, and at least one or more guide recesses for drilling gas holes are provided on each of the crater surfaces of the central crater portion and the crater portion corresponding to the rebar diameter. On the other hand, the gas supply path forming part is formed to have a crater surface One end in the axial direction is bent at a predetermined angle on the side of the crater face forming part, and a build-up part is formed at a location close to the crater face forming part on the other end side. A forged piece used as a crater for gas pressure welding. 4. A connecting portion to a gas supply pipe provided at one end or both ends of a piece main body gas supply passage is provided so that an angle of an axis of the gas supply passage with respect to an axis of the gas supply passage and a center of the gas supply passage can be adjusted. It is approximately 135 in the plane passing through the axis of the crater.
4. A forged piece as a cradle piece for gas pressure welding according to any one of claims 1 to 3, wherein the forged piece is formed so as to be restricted to about to 150 degrees. 5. A crater face forming portion of a piece body formed by integrally forming a horizontal rod-shaped gas supply path forming portion on the back side of a relatively thick plate-shaped crater face forming portion, wherein the crater face forming portion is located at the center of the crater face. At the top and bottom of the central crater portion, at least one each of the reinforcing bar axial position crater portions is arranged in a line and symmetrically, and on the left and right sides of the central crater portion and each reinforcing bar crater portion, The craters corresponding to the rebar diameter are arranged in a line in a symmetrical manner, and the center crater and the adjacent craters for the rebar diameter are arranged vertically and horizontally around each crater face, and the piece body An air supply groove is provided so as to be in communication with the outer peripheral edge, and at least one or more guide recesses for drilling gas holes are provided on each of the crater surfaces of the central crater portion and the crater portion corresponding to the rebar diameter. Forging piece body to be a crater piece for gas pressure welding,
In each of the guide recesses, a gas hole reaching the gas supply path forming section at a predetermined angle is formed, and a gas supply path having a predetermined inner diameter is formed only at one end of the gas supply path forming section or at both ends. At one end or both ends of the gas supply path, the angle with respect to the axis of the gas supply path is within the plane passing through the gas supply path and the central axis of the central crater, and the shape and dimensions of the gas pressure welding burner to be used. About 13 according to
A method for manufacturing a cradle piece for gas pressure welding, wherein a connection portion of a gas supply pipe portion regulated to a range of about 5 to 150 degrees is appropriately cut. 6. A crater face forming part of a piece body in which a horizontal rod-shaped gas supply path forming part is integrally formed on the back side of a relatively thick plate-shaped crater face forming part, the crater face forming part is located at the center of the crater face. At the top and bottom of the central crater portion, at least one each of the reinforcing bar axial position crater portions is arranged in a line and symmetrically, and on the left and right sides of the central crater portion and each reinforcing bar crater portion, The craters corresponding to the rebar diameter are arranged in a line in a symmetrical arrangement, and the center crater and the crater adjacent to the rebar diameter are arranged vertically and horizontally around each crater face between the adjacent craters. An air supply groove is provided so as to be in communication with the outer peripheral edge, and at least one or more guide recesses for drilling gas holes are provided on each of the crater surfaces of the central crater portion and the crater portion corresponding to the rebar diameter. On the other hand, the gas supply path forming portion is located at one end in the axial direction. However, for the forged piece which is a gas pressure welding crater piece which is formed by bending at a predetermined angle on the side of the crater face forming part, in each guide recess, a gas hole reaching the gas supply path forming part at a predetermined angle. Each of the gas supply passages is formed with a gas supply passage having a predetermined inner diameter that is penetrated only from one end of the gas supply passage formation portion or both ends, and the shaft of the gas supply passage is formed at one end or both ends of the gas supply passage formation portion. Gas supply whose angle with respect to the core is restricted within a range of about 135 to 150 degrees in a plane passing through the gas supply path and the substantially central axis of the central crater, depending on the shape and dimensions of the gas pressure burner to be used. A method for manufacturing a crater for gas pressure welding, wherein a connecting portion of a pipe portion is appropriately cut. 7. A crater surface forming portion of a piece body integrally formed with a horizontal rod-shaped gas supply path forming portion on the back side of a relatively thick plate-shaped crater surface forming portion, wherein the crater surface forming portion is located at the center of the crater surface. At the top and bottom of the central crater portion, at least one each of the reinforcing bar axial position crater portions is arranged in a line and symmetrically, and on the left and right sides of the central crater portion and each reinforcing bar crater portion, The craters corresponding to the rebar diameter are arranged in a line in a symmetrical arrangement, and the center crater and the crater adjacent to the rebar diameter are arranged vertically and horizontally around each crater face between the adjacent craters. An air supply groove is provided so as to be in communication with the outer peripheral edge, and at least one or more guide recesses for drilling gas holes are provided on each of the crater surfaces of the central crater portion and the crater portion corresponding to the rebar diameter. On the other hand, the gas supply path forming part is formed to have a crater surface One end in the axial direction thereof is bent at a predetermined angle to the crater face forming portion side, and a portion close to the crater face forming portion on the other end side is formed with a built-up portion for gas pressure welding. In the forged piece body to be the crater piece, a gas hole reaching the gas supply path forming portion is formed at a predetermined angle in each guide recess, and a penetrating shape is formed only at one end of the gas supply path forming portion or at both ends. A gas supply path having a predetermined inner diameter is bored, and is used at one end of the gas supply path in a plane where the angle with respect to the axis of the gas supply path passes through the gas supply path and the substantially central axis of the central crater. Depending on the shape and size of the gas pressure welding burner, the connecting portion of the gas supply pipe portion, which is restricted to a range of about 135 ° to 150 °, is appropriately cut and processed. Cut the connection of the gas supply pipe section 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 form a gas hole reaching the gas supply path forming portion at a predetermined angle, and to penetrate only from one end side or both ends of the gas supply path forming portion. The gas supply passage is pierced, and at one end or both ends of the gas supply passage, the angle with respect to the axis of the gas supply passage is used in a plane passing through the gas supply passage and the substantially central axis of the central crater portion. Depending on the shape and dimensions of the burner, a plurality of gas pressure welding crater pieces obtained by appropriately cutting the connection part of the gas supply pipe part that is restricted to a range of about 135 degrees to about 150 degrees, centering on the rebar to be welded All the crater pieces for gas pressure welding are connected at equal intervals along a circle drawn with the radius of the separation distance that is optimal for pressure welding, and connecting a plurality of gas supply pipes located outside the circle. But one blowpipe installation A gas pressure welding burner using a gas pressure welding crater piece using the forged piece body according to any one of claims 1 to 4, wherein the burner piece is connected to communicate with the mouth. 9. A gas hole reaching a gas supply path forming portion at a predetermined angle in each of the guide recesses, and a gas having a predetermined inner diameter that penetrates only from one end side or both ends of the gas supply path forming portion. The supply passage is bored, and at one end of the gas supply passage, the angle with respect to the axis of the gas supply passage is within a plane passing through the gas supply passage and the substantially central axis of the central crater portion. Approx. 1 according to shape and dimensions
The connection part of the gas supply pipe part which is regulated within the range of about 35 ° to 150 ° is appropriately cut, and the connection part of the gas supply pipe part reaching the inside of the cladding part is provided on the other end side as necessary. A plurality of crater pieces for gas pressure welding, which are appropriately cut, are arranged at equal intervals along the circle drawn with the optimal separation distance radius centering on the rebar to be welded, and on the outside of the circle 4. A forged piece body according to claim 3, wherein a plurality of gas supply pipe portions are connected to each other, and all the gas pressure welding crater pieces are connected so as to communicate with one blow pipe mounting port. Gas pressure welding burner using a gas pressure welding crater.