Nozzle, heating torch using the same, and gas pressure-welding method

Abstract

To provide a nozzle that, when pressure-welding a pressure-welding material using standard flame, can suppress oxidation on a pressure-welding surface by using the standard flame from initial heating without using a reduction material, and can further suppress oxidation when used in combination with the reduction material.SOLUTION: A nozzle A1 comprises: a hollow nozzle substrate 1 having a fire hole 20 at its tip part; and a flow dividing member 3 that is provided near the fire hole 20 of the nozzle substrate 1 and crosses the fire hole 20, and that divides gas flow passing through the fire hole 20 into two directions to form a non-heated area of a predetermined width.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a nozzle, a heating torch using the nozzle, and a gas pressure welding method. More specifically, the present invention relates to a nozzle that can suppress oxidation even when using a standard flame from the initial heating stage when welding pressure welding materials using a standard flame that uses propane gas or the like as fuel gas, which is stably available regardless of region and has a small environmental impact. [Background technology]

[0002] For example, in gas pressure welding of rebars using acetylene gas, it is necessary to polish the welded surfaces of the rebars and to heat them initially with a reducing flame until the tip faces come into close contact. If the initial heating is performed with a standard flame (neutral or oxidizing flame), an oxide film will form on the welded surfaces, resulting in poor bonding and fracture of the welded surfaces.

[0003] On the other hand, the use of natural gas and propane gas, which have a lower heat output than acetylene gas but are easy to handle and have a small environmental impact, has long been a concern. In other words, when attempting to use these gases for pressure welding, in order to obtain the same heat output as acetylene gas, it is necessary to use a standard flame from the initial heating stage, and in this case, measures are required to prevent the formation of an oxide film on the welded surfaces.

[0004] As one of the countermeasures, the gas pressure welding method is used, in which a cap-shaped PS ring containing a polystyrene sheet and a steel ring is used as a reducing agent (or oxidation inhibitor) when pressure welding reinforcing bars, etc. However, the use of reducing agents in pressure welding methods has the problem of high costs. Also, since the reducing agent is sandwiched between the pressure welding surfaces of reinforcing bars, etc., the heating efficiency tends to decrease, which can lead to the problem of an oxide film easily forming on the pressure welding surfaces.

[0005] Therefore, even when a standard flame is used, it is assumed that these problems can be solved if the flame is not directly applied to the welded surface and the vicinity of the welded surface can be sufficiently heated, but up to now, there have been almost no proposals for a technology to split the flame used in the welded method with a nozzle. For example, in terms of burners, a high-velocity jet-type diffusion combustion burner (Patent Document 1) has been proposed, which is said to achieve an optimal temperature distribution inside the furnace by adjusting the flame length by reducing the straightness of the fuel gas. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2009-299955 A Summary of the Invention [Problem to be solved by the invention]

[0007] In the above-mentioned conventional high-velocity jet type diffusion combustion burner, the diffusion tip can diffuse the fuel gas toward the primary air flowing outside of it. However, because the diffusion tip is cone-shaped, the flame remains normal even if it expands, and it could not be used as a nozzle structure for the pressure welding method, which requires the flame to be divided in the direction sandwiching the pressure welding surface.

[0008] The present invention has been devised in consideration of the above points, and aims to provide a nozzle that makes it possible to suppress oxidation even when a standard flame is used from the initial heating stage, for example when pressure welding of pressure welding materials using a standard flame that uses propane gas or the like as fuel gas, which is steadily available regardless of region and has a small environmental impact, as well as a heating torch and gas pressure welding method that use the same. [Means for solving the problem]

[0009] [1] In order to achieve the above-mentioned object, the present invention provides a burner comprising a hollow burner base having a fire hole at its tip, and a flow dividing member disposed in the vicinity of the fire hole of the burner base so as to cross the fire hole and which divides the gas flow passing through the fire hole into two directions to form a non-heated area of ​​a predetermined width.

[0010] The nozzle of the present invention is capable of directing combustible gas through a hollow nozzle base toward a fire hole at the tip. A flow dividing member is provided near the fire hole in the nozzle base so as to cross the fire hole, and the gas flow passing through the fire hole can be divided into two directions.

[0011] By dividing the gas flow into two directions with the flow dividing member, the flame when heating the pressure welding material is also divided into two directions. Each divided flame heats a specific location of the pressure welding material, and a non-heated area (including a heated area that is not heated enough for pressure welding) of a specific width (or size) is formed between the divided flames.

[0012] As a result, when pressure welding the pressure welding material, by aligning a non-heated area with the pressure welding surface of the pressure welding material, when pressure welding the pressure welding material using a standard flame that uses propane gas or other fuel gas, which is steadily available and has a small environmental impact, it is possible to use the standard flame from the initial heating and prevent oxidation at the pressure welding surface without using a reducing agent, and when used in combination with a reducing agent, further oxidation prevention is possible.

[0013] [2] The burner of the present invention in [1] may also be configured such that the diverting member is provided at a predetermined distance from the tip of the fire hole toward the inside of the burner base.

[0014] When the front of the fire hole is open and normal heating is being performed by the flame, the flow diverter is separated from the flame and is not heated at all. This prevents the flow diverter from deteriorating due to heat and maintains a certain strength. This prevents the flow diverter from being damaged by the impact even if the front of the fire hole is blocked and a backfire occurs.

[0015] [3] The burner of the present invention, in [1] and [2], can also be configured such that the burner base has a base member and a tip member attached to the base member and having the fire hole formed therein, and the diverting member is arranged to be rotatable in a direction intersecting its axial direction while maintaining a state across the fire hole.

[0016] In this case, when the flow dividing member is attached to the tip member, it is possible to adjust the circumferential angle by rotating it. This makes it possible to align (or overlap) the non-heated area generated by dividing the gas flow in two directions with the pressure welding surface of the pressure welding material.

[0017] [4] In the burner of the present invention, in [1] or [2], the burner base can also be configured to have a base member and a tip member that is rotatably attached to the base member and has the fire hole formed therein.

[0018] In this case, the angle of the flow dividing member in the circumferential direction can be adjusted by rotating the tip member, which is arranged so that the flow dividing member crosses the fire hole, relative to the base member, which makes it possible to align the non-heated area, which is generated by dividing the gas flow in two directions, with the pressure welding surface of the pressure welding material.

[0019] [5] The nozzle of the present invention in [1] may further include a gas guide section located inside the nozzle base, which introduces combustible gas into the nozzle base and cooperates with the nozzle base to guide the combustible gas to the fire hole, and the flow diverter member is provided at the tip of the gas guide section so as to cross the gas outlet leading to the fire hole.

[0020] In this case, the combustible gas can be introduced and guided to the fire hole by the gas guide section inside the fire hole base. The flow dividing member is provided at the tip of the gas guide section so as to cross the gas nozzle leading to the fire hole, so that the gas passing through the gas nozzle can be divided into two by the flow dividing member and ejected through the fire hole.

[0021] [6] The nozzle of the present invention, in [5], can also be configured such that the gas guide portion is provided separately from the nozzle base, is rotatable in the circumferential direction relative to the nozzle base, and is fixable at a predetermined position.

[0022] In this case, the gas guide is provided separately from the nozzle base and can rotate in the circumferential direction relative to the nozzle base, so that the angle of the flow dividing member in the circumferential direction can be adjusted. This makes it possible to align the non-heated area generated by dividing the gas flow in two directions with the pressure welding surface of the pressure welding material.

[0023] [7] The nozzle of the present invention, in [5] and [6], can also be configured such that the tip of the gas guide portion is formed in a gear shape to form a gas passage between the tip and the nozzle base, and each tooth of the gear is arranged so as to draw a spiral over the entire length of the gas guide portion in the axial direction.

[0024] In this case, the tip of the gas guide is gear-shaped to form a gas passage between the tip and the nozzle base, and each tooth of the gear is arranged to draw a spiral along the entire length of the axial direction of the gas guide, so that the gear groove forms an air passage between the tip and the inner surface of the nozzle base, and the air passage is spiral. From the outlet of each air passage, the gas flow is ejected at a predetermined angle to the longitudinal direction of the gas guide and is discharged in a swirling manner.

[0025] This expands the area where the outer flame is formed, and this area serves to prevent oxygen from the atmosphere from being drawn into the inner flame, preventing oxygen from the atmosphere from being drawn into the welded surfaces of the welded material. This prevents the formation of an oxide film on the welded surfaces, allowing the welded surfaces to be joined well.

[0026] [8] In order to achieve the above object, the present invention provides a heating torch comprising burner tubes arranged opposite each other, a flow dividing member arranged inside the burner tubes and crossing a fire hole, the flow dividing member being attached so as to direct the fire hole toward the center inside each burner tube and to divide the gas flow passing through the fire hole into two directions to form a non-heated area of ​​a predetermined width, and the flow dividing member being arranged so that the length direction is approximately parallel to the center line along the longitudinal direction of the burner tube, and a plurality of fire holes.

[0027] In the heating torch of the present invention, the burner tubes provided opposite each other can be arranged at a position that is approximately centered on the pressure welding material. Also, since a plurality of flame holes having a flow dividing member that crosses the flame hole are attached so that the flame hole faces the inside of each burner tube and the gas flow passing through the flame hole is divided into two directions to form a non-heated area with a predetermined width, it is possible to heat the pressure welding material arranged at the center inside each burner tube.

[0028] In addition, the flow-diverting members of each nozzle are arranged so that their length is approximately parallel to the center line along the longitudinal direction of the burner tube, so that it is possible to align the non-heated area between the two split flames with the pressure-welded surface of the pressure-welded material.

[0029] In this way, by aligning the non-heated area with the welded surface of the welded material when welding the welded material, oxidation at the welded surface can be suppressed without the use of a reducing agent by using a standard flame with propane gas or other fuel gas from the initial heating. In addition, by using a reducing agent in combination, oxidation can be further suppressed.

[0030] [9] In order to achieve the above object, the present invention provides a gas pressure welding method comprising a step of dividing the gas flow passing through the nozzle hole of the nozzle into two directions to form a non-heated area of ​​a predetermined width, and heating the non-heated area so that it overlaps with the pressure welding surface of the pressure welding material.

[0031] The gas pressure welding method of the present invention divides the gas flow passing through the nozzle hole in two directions to form a non-heated area of ​​a specified width, and heating is performed so that the non-heated area overlaps the pressure welding surface of the pressure welding material, thereby preventing oxidation at the pressure welding surface.

[0032]

[10] In the gas pressure welding method of the present invention described in [9], the heating may be performed using a standard flame.

[0033] In this case, heating is performed with a standard flame, so even if propane gas or other gas other than acetylene is used, sufficient heat can be obtained for the pressure welding method. This allows the use of a standard flame from the initial heating stage, preventing oxidation on the pressure welding surface. In addition, the use of a reducing agent can further prevent oxidation. Effect of the Invention

[0034] The present invention can provide a nozzle which can suppress oxidation at the pressure welding surface without using a reducing agent by using a standard flame from the initial heating when pressure welding pressure materials using a standard flame that uses propane gas or the like as a fuel gas that is steadily available regardless of region and has a small environmental impact, and which can further suppress oxidation when used in combination with a reducing agent, as well as a heating torch and gas pressure welding method using the same. [Brief description of the drawings]

[0035] [Figure 1] FIG. 2 is an exploded perspective view showing the structure of the first burner of the present invention. [Diagram 2] FIG. 2 is a vertical cross-sectional view of the first nozzle shown in FIG. 1 in an assembled state. [Diagram 3] 2 is a perspective view showing the structure of the tip member of the first nozzle shown in FIG. 1, as viewed from below. FIG. [Figure 4] FIG. 2 is an exploded perspective view showing the structure of a second nozzle of the present invention. [Diagram 5] FIG. 5 is a vertical cross-sectional view of the second nozzle shown in FIG. 4 in an assembled state. [Figure 6] FIG. 4 is an explanatory diagram showing the structure of a gas director of the second nozzle. [Figure 7] FIG. 4 is a cross-sectional view showing the structure of a gas director of the second nozzle. [Figure 8] FIG. 11 is a vertical cross-sectional view of a third nozzle of the present invention. [Figure 9] FIG. 11 is a perspective view showing the structure of a gas guide of the third burner. [Figure 10] FIG. 13 is a perspective view of the main part of a heating torch equipped with a fourth burner nozzle of the present invention. [Figure 11] FIG. 13 is a perspective view of the main part of a heating torch equipped with a fifth burner nozzle of the present invention. [Figure 12] FIG. 11 is a partial cross-sectional explanatory view showing the structure of the fifth crater nozzle. [Figure 13] FIG. 2 is a schematic plan view of the heating torch of the present invention. [Figure 14] FIG. 14 is an explanatory diagram showing the arrangement of each nozzle provided in the heating torch of FIG. 13. [Figure 15] FIG. 2 is a partial cross-sectional view showing the direction of flame diversion in the nozzle of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0036] The embodiment of the present invention will be described in more detail with reference to FIGS. First, the structure of a first nozzle A1 according to the present invention will be described with reference to Figs. The first nozzle A1 is made of metal (for example, brass), but is not limited to this and may be made of a metal material with better fire resistance, as is the case with the nozzles A2 to A5 described below.

[0037] The first nozzle A1 has a nozzle base 10. The nozzle base 10 is a hollow body having a space 100 penetrating in the length direction (the vertical direction in FIG. 2) in the center. The nozzle base 10 is composed of a base member 1 and a tip member 2.

[0038] The base member 1 has, in order from the base end side (the lower end side in FIG. 2), a lower threaded pipe portion 11, a flange portion 12, and an upper threaded pipe portion 13. In this embodiment, the portion between the flange portion 12 and the upper threaded pipe portion 13 is a tip member remaining portion 16 having a flat hexagonal column shape.

[0039] The lower threaded pipe portion 11 has a male thread (reference number omitted) on the outer periphery. In addition, in the above-mentioned space 100, a portion that generally corresponds to the lower threaded pipe portion 11 is a tapered hole 14 having a larger inner diameter on the lower side. The cross-sectional shape of the tapered hole 14 is circular.

[0040] Of the space 100, the space located above the tapered hole 14 is a press-fit hole 15 having a diameter larger than the inner diameter of the upper end of the tapered hole 14. The press-fit hole 15 has a circular cross-sectional shape and is located at a position that generally corresponds to the upper threaded pipe portion 13 and the flange portion 12 (see FIG. 2).

[0041] The gas guide 4 is accommodated and fixed in the press-fit hole 15. The gas guide 4 has a neck 40 that is larger in diameter than the inner diameter of the upper end of the tapered hole 14 and is hung on the step between the tapered hole 14 and the press-fit hole 15. A spur gear-shaped guide portion 41 (reference: guide portion 41a in FIG. 4) is provided on the upper portion of the neck 40.

[0042] The outer diameter (maximum diameter) of the induction portion 41 is formed slightly larger than the inner diameter of the press-fit hole 15, and the gas guiding portion 4 is press-fitted into the press-fit hole 15 and fixed so that its upper end is located lower than the upper end of the upper threaded tube portion 13 (see FIG. 2). As a result, between the inner periphery of the press-fit hole 15 and the induction portion 41, eight air passages 400 (for convenience, indicated by symbols in FIG. 2) are formed over the entire length of the induction portion 41 at eight positions in the circumferential direction of the induction portion 41.

[0043] A gas feed hole 45 is provided over the entire length of the central portion of the gas director 4. Furthermore, the neck portion 40 is provided with communication holes 43 at two diametrical positions which penetrate the peripheral wall and communicate with the gas feed hole 45.

[0044] The tip member 2 has an outer shape of a substantially hexagonal column, and its base side is a threaded tube portion 21. A circular fire hole 20 having a predetermined inner diameter is formed at the tip of the tip member 2. The inner circumference of the threaded tube portion 21 has a female thread (reference number omitted).

[0045] The pitch number of the female thread is made larger than the pitch number of the male thread of the upper threaded tube portion 13, so that there is an excess screwing portion even when the tip member 2 is tightened (see FIG. 2). The fire hole 20 and the inner periphery of the threaded tube portion 21 form the space 100.

[0046] In addition, a flow diverting member 3 is attached to the female thread of the threaded tube portion 21 of the tip member 2. The flow diverting member 3 is a pin-shaped member of a predetermined length with a circular cross section. Both ends of the flow diverting member 3 can be fitted into the grooves of the female thread to span the length.

[0047] The flow diverting member 3 is rotated along the groove in a direction intersecting the axial direction of the flow diverting member 3 while being kept in a state of crossing the fire hole 20. This allows the flow diverting member 3 to be fixed at an arbitrary depth position of the female thread (the remaining portion of the male and female threads). This also allows the flow diverting member 3 to be positioned a certain distance away from the fire hole 20, slightly inside the space 100.

[0048] The material of the flow dividing member 3 is, for example, stainless steel, but is not limited to this and other metal materials can be used as long as they have sufficient fire resistance (heat resistance). In addition, although the cross-sectional shape is circular in this embodiment, it is not limited to this and can be formed into, for example, an ellipse, a triangle, a rectangle, or other polygonal shape in order to divide the direction of the flame into two. The same applies to the fire ports A2 to A5 described later.

[0049] The tip member 2 to which the diversion member 3 is attached is then fastened to the base member 1 to which the gas guide 4 is fixed by screwing the female thread of the threaded tube portion 21 into the male thread of the upper threaded tube portion 13 of the base member 1, and is fixed to the base member 1 and integrated to form the nozzle A1.

[0050] The flow dividing member 3 attached to the tip member 2 is pressed by the upper end of the upper threaded pipe portion 13 when the tip member 2 and the base member 1 are integrated, and is adjusted so as to form a predetermined angle in the circumferential direction. This angle is an angle at which the flow dividing member 3 is parallel to the pressure welding surfaces 500 of the materials to be pressure welded 51, 52 when the tip member 2 is incorporated into the heating torch 9 as described later.

[0051] Now, the heating torch 9 of the present invention will be described with reference to FIGS. The heating torch 9 in which the nozzle A1 is incorporated is a heating torch for gas pressure welding. The heating torch 9 has a gas inlet pipe 90 for introducing a combustible gas. A combustible gas supply pipe having a valve (reference numerals omitted) and an oxygen supply pipe (both not shown) are connected to the base of the gas inlet pipe 90 so that they can join together.

[0052] A U-shaped branch pipe 91 is connected to the tip of the gas inlet pipe 90, and burner pipes 92 and 93, which are branch horizontal pipes, are connected to both ends of the branch pipe 91 in opposing directions. The center lines of the gas inlet pipe 90, branch pipe 91, and burner pipes 92 and 93 are on the same plane (normally on a horizontal plane when installed).

[0053] Four nozzles A1 are attached to the inside of each of the burner tubes 92 and 93. In the present embodiment, the number of nozzles is four for each, but this is not limited thereto, and if the diameter of the pressure welding material is large, the number may be set to, for example, 5 to 10.

[0054] Each nozzle A1 has its fire hole 20 facing inward (towards the center on the same plane), and the diversion member 3 located near each fire hole 20 is set so as to be approximately at the same height as and approximately parallel to the center lines of the burner tubes 92, 93 (see Figure 14).

[0055] In addition, above and below the nozzle A1 at the front and rear ends of the burner tubes 92, 93, nozzles A0 for heating portions slightly above and below the pressure contact surfaces 500 of the pressure contact materials 51, 52 are provided at a slight angle above and below the horizontal and facing inward in the same manner as nozzle A1.

[0056] (Action of nozzle A1 and heating torch 9) The nozzle A1 is attached to a predetermined position of the burner tubes 92, 93 of the heating torch 9. The nozzle A1 is fixed by screwing the lower threaded tube portion 11 of the nozzle base 10 into the mounting tube 94, which is a threaded tube provided on the burner tubes 92, 93 (see Figures 13 to 15).

[0057] Combustible gas (e.g., a mixture of propane gas and oxygen) can be supplied to the nozzle A1 fixed to the mounting tube 94. The combustible gas is introduced from the tapered hole 14 of the base member 1 and enters the gas supply hole 45 of the gas derivative 4. The pressure of the combustible gas passing through the gas supply hole 45 is maintained at a substantially constant high pressure, and a portion of the combustible gas is ejected from the tip of the gas supply hole 45 toward the fire hole 20.

[0058] Another part of the combustible gas enters the space 100 from the gas supply hole 45 through the communication hole 43, passes through each ventilation path 400, and merges with the combustible gas ejected from the tip of the gas supply hole 45. The merged combustible gas ejects to the outside through the fire hole 20, but before ejecting, it is divided into two directions by the flow dividing member 3 located slightly inside the space 100, away from the fire hole 20.

[0059] As a result, the flame after ignition is divided into flame F1 and flame F2, and a non-heated region a1 is formed. In Fig. 15, for the sake of convenience, the non-heated region a1 is shown in the press materials 51 and 52, and is aligned with the press surface 500. The term non-heated region does not only mean a region that is not heated at all, but also includes the meaning of a heated region that is not heated enough for press welding.

[0060] Furthermore, by using the heating torch 9 incorporating the nozzle A1, even if a standard flame using propane gas or the like as a fuel gas is used from the initial heating when pressing the press-welding materials 51, 52, the standard flames F1, F2 do not directly heat the press-welding surface 500 in the non-heated area a1, so that the formation of an oxide film on the press-welding surface 500 can be prevented (oxidation prevention) without using a reducing agent.

[0061] In this embodiment, the pressure welding materials 51, 52 are supported in a vertical direction, and the burner tubes 92, 93 of the heating torch 9 are positioned horizontally to perform gas pressure welding; however, this is not limited to this, and the pressure welding materials 51, 52 can also be supported horizontally and the burner tubes 92, 93 of the heating torch 9 can be positioned vertically to perform gas pressure welding.

[0062] Next, the structure of the second nozzle A2 according to the present invention will be described with reference to Figs. The second nozzle A2 has a nozzle base 10a. The nozzle base 10a is a hollow body having a space 100a penetrating in the length direction (vertical direction in FIG. 5) in the center. The nozzle base 10a has, in order from the base end side (lower end side in FIG. 4), a lower screw pipe section 11a, a flange section 12a, and an upper pipe section 18a having an outer shape of a substantially hexagonal column.

[0063] The lower threaded pipe portion 11a has a male thread (reference numeral omitted) on the outer periphery. In addition, in the space 100a, a screw hole 17a is provided on the inner periphery of a portion that corresponds approximately to the lower threaded pipe portion 11a and the flange portion 12a (see FIG. 5).

[0064] Of space 100a, the space located above screw hole 17a penetrates the upper end surface of upper tube portion 18a, and its tip forms a circular fire hole 180. Also, at one location on the peripheral wall of upper tube portion 18a, a screw hole 19 is provided penetrating the peripheral wall. A set screw 190 is screwed into screw hole 19.

[0065] A gas guide 4a is accommodated inside the space 100a and is attached at a predetermined position (height). The gas guide 4a is provided with a lower screw tube portion 42a having a male screw (reference number omitted) on the outer periphery, a neck portion 40a having a smaller diameter than the space forming the fire hole 180, and a spur gear-shaped guide portion 41a, in this order from the base end side. In addition, engagement recesses 44a for engaging a rotation operating tool such as a screwdriver are provided at two points on the diameter line of the lower screw tube portion 42a.

[0066] The outer diameter of the induction portion 41a is slightly smaller than the inner diameter of the portion above the screw hole 17a in the space 100a, and the portion of the gas guiding portion 4a is rotatable and movable forward and backward in the circumferential direction along the inner periphery of the space 100a. In addition, between the inner periphery of the portion above the screw hole 17a in the space 100a and the induction portion 41a, eight ventilation paths 400 (shown in Figs. 4 and 5 for convenience) are formed in the circumferential direction of the induction portion 41a over the entire length of the induction portion 41a.

[0067] A gas feed hole 45a is provided in the center of the gas guide 4a over its entire length. The upper end of the gas feed hole 45a is a gas outlet 450. The gas feed hole 45a is a circular hole of the same diameter at the tip side corresponding to the guide portion 41a and the neck portion 40a, and is a tapered hole whose diameter increases downward at the base side corresponding to the lower screw tube portion 42a (see Figs. 5 and 7). The neck portion 40a is also provided with communication holes 43a at two diametrical positions that penetrate the peripheral wall and communicate with the gas feed hole 45a.

[0068] A stainless steel flow diverter 3a is attached to the tip of the gas guide 4a so as to cross the gas outlet 450 in the diametric direction outside the gas outlet 450. The flow diverter 3a is a pin-shaped member with a circular cross section and a predetermined length. The flow diverter 3a is fixed, for example, by inserting one end into a through hole 47 provided in the guide 41a corresponding to the groove of the spur gear, rotating it upward so as to cross the gas outlet 450, and bending the other end to fit it in the groove (see Figs. 6 and 7).

[0069] In addition, gas diversion can also be performed by providing a through hole 47 on the opposite side of the gas guide 4a, making the diversion member into a straight pin shape without bending the end like the diversion member 3a, and passing it through both through holes 47 and fixing the gas outlet 450 horizontally.

[0070] 4 and 5, the gas guide 4a can be screwed into the space 100a by inserting the guide part 41a into the screw hole 17a of the nozzle base 10a, and rotating and screwing the male thread of the lower screw tube part 42a into the female thread of the screw hole 17a. Even if the guide part 41a enters the part of the space 100a where the fire hole 180 is located, the gas guide 4a can be screwed further into the space 100a and fixed by tightening the set screw 190 at an appropriate position, and the gas guide 4a is integrated into the nozzle A2.

[0071] The flow dividing member 3a provided on the gas conductor 4a is fixed by the set screw 190 when the gas conductor 4a and the nozzle base 10a are integrated, and is positioned slightly inward from the fire hole 180 and adjusted to a predetermined angle in the circumferential direction. This angle is an angle that becomes parallel to the pressure welding surfaces 500 of the materials to be pressure welded 51, 52 when the gas conductor 4a is attached to the heating torch 9 and assembled.

[0072] (Action of crater A2) The nozzle A2 is attached to the burner tubes 92 and 93 of the heating torch 9 in the same manner as the nozzle A1. The nozzle A2 is fixed by screwing the lower threaded tube portion 11a of the nozzle base 10a into the mounting tube 94, which is a threaded tube provided on the burner tubes 92 and 93. At this time, the flow dividing member 3a is set to be approximately the same height as the center lines of the burner tubes 92 and 93 and approximately parallel to them.

[0073] Combustible gas can be supplied to the nozzle A2 fixed to the mounting tube 94. The combustible gas is introduced through the screw hole 17a of the nozzle base 10a and enters the gas supply hole 45a of the gas guide 4a. The pressure of the combustible gas passing through the gas supply hole 45a is maintained at a substantially constant high pressure, and a portion of the combustible gas is ejected from the gas ejection port 450 at the tip of the gas supply hole 45a toward the fire hole 180.

[0074] Another part of the combustible gas enters space 100a from gas supply hole 45a through communication hole 43a, passes through each ventilation path 400, and merges with the combustible gas ejected from gas ejection port 450. The merged combustible gas is ejected to the outside through fire hole 180, but before ejecting, it is divided into two directions by flow dividing member 3a located slightly inside space 100a, away from fire hole 180. As a result, the flame after ignition is divided into flame F1 and flame F2 (see FIG. 15), and a non-heated region a1 is formed.

[0075] The gas conductor 4a of the nozzle A2 can rotate in its circumferential direction, and the angle in the circumferential direction can be adjusted by rotating the flow dividing member 3a. This makes it possible to align the non-heated area a1, which is generated by dividing the gas flow in two directions, with the pressure-welded surface of the pressure-welded material. The gas conductor 4a can also be moved forward and backward by rotating it to change the screwing position of the lower screw tube portion 42a, so that the distance from the fire hole 180 can be adjusted when necessary.

[0076] Next, the structure of the third nozzle A3 according to the present invention will be described with reference to Figs. The third nozzle A3 has a nozzle base 10a. The nozzle base 10a has the same structure as the nozzle base 10a of the above-mentioned nozzle A2, so a description of the structure will be omitted here.

[0077] A gas guide 4b is accommodated in the space 100a of the burner base 10a and is attached at a predetermined position (height). The gas guide 4b is provided with a lower screw tube portion 42b having a male screw (reference number omitted) on the outer periphery, a neck portion 40b having a smaller diameter than the space forming the fire hole 180 described later, and a guide portion 41b, in this order from the base end side. The guide portion 41b is provided such that each gear-shaped tooth forms a spiral over the entire length in the axial direction of the gas guide portion 41b. In addition, the lower screw tube portion 42b is provided with engagement recesses 44b at two points on the diameter line for engaging a rotation operating tool such as a screwdriver.

[0078] The outer diameter of the induction part 41b is slightly smaller than the inner diameter of the part above the screw hole 17a in the space 100a, and the part of the gas guiding part 4b is rotatable and movable forward and backward along the inner periphery of the space 100a. In addition, between the inner periphery of the part above the screw hole 17a in the space 100a and the induction part 41b, eight ventilation paths 400 are formed in the circumferential direction of the induction part 41b over the entire length of the induction part 41b.

[0079] A gas feed hole 45b is provided in the center of the gas guide 4b over its entire length. The upper end of the gas feed hole 45b is a gas outlet 450. The gas feed hole 45b is a circular hole of the same diameter at the tip side corresponding to the guide portion 41b and the neck portion 40b, and is a tapered hole whose diameter increases downward at the base side corresponding to the lower screw tube portion 42b. In addition, the neck portion 40b is provided with communication holes 43b at two diametrical positions that penetrate the peripheral wall and communicate with the gas feed hole 45b.

[0080] A stainless steel pin-shaped flow diverter 3b having a circular cross section and a predetermined length is attached to the tip of the gas director 4b in the same manner as the flow diverter 3a, so as to cross the gas outlet 450 in the diametric direction outside the gas outlet 450. The gas director 4b is screwed and attached to the nozzle base 10a in the same manner as the induction part 41a, as shown in Fig. 8, and is integrated with the nozzle A3.

[0081] The flow dividing member 3b provided on the gas guide 4b is fixed by the set screw 190 and positioned slightly inward from the fire hole 180 when the gas guide 4b and the nozzle base 10a are integrated, and is adjusted so as to form a predetermined angle in the circumferential direction. This angle is an angle that becomes parallel to the pressure welded surfaces 500 of the materials to be welded 51, 52 when the gas guide 4b is attached and assembled to the heating torch 9, similar to the above nozzles A1 and A2.

[0082] (Function of Nozzle A3) The nozzle A3 is attached to the burner tubes 92 and 93 of the heating torch 9 in the same manner as the nozzle A1. The nozzle A3 is fixed by screwing the lower threaded tube portion 11a of the nozzle base 10a into the mounting tube 94, which is a threaded tube provided on the burner tubes 92 and 93. At this time, the flow dividing member 3b is set to be approximately the same height as the center lines of the burner tubes 92 and 93 and approximately parallel to them.

[0083] Combustible gas can be supplied to the nozzle A3 fixed to the mounting tube 94. The combustible gas is introduced through the screw hole 17a of the nozzle base 10a and enters the gas supply hole 45b of the gas guide 4b. The pressure of the combustible gas passing through the gas supply hole 45b is maintained at a substantially constant high pressure, and a part of the combustible gas is ejected from the gas ejection port 450 at the tip of the gas supply hole 45b toward the fire hole 180.

[0084] Another part of the combustible gas flows from gas supply hole 45b through communication hole 43b into space 100a, passes through each ventilation passage 400, and merges with the combustible gas ejected from gas ejection port 450. The merged combustible gas passes through fire hole 180 and is ejected to the outside.

[0085] Before being ejected, the gas flow is ejected from the outlet of each ventilation passage 400 at a predetermined angle to the longitudinal direction of the gas inductor 4b and is ejected so as to swirl, and is further divided into two directions by the flow dividing member 3b located slightly inside the space 100a and away from the fire hole 180. As a result, the flame after ignition is divided into flame F1 and flame F2 (see FIG. 15), and a non-heated region a1 is formed.

[0086] The gas flow is discharged in a swirling manner from each ventilation passage 400, expanding the area where the outer flame is formed, and the outer flame formation area serves to suppress the inclusion of oxygen in the atmosphere in the inner flame. Furthermore, by suppressing the inclusion of oxygen in the atmosphere in the press-fitted surfaces 500, which are the butt joints of the press-fitted materials 51, 52, the formation of an oxide film on the press-fitted surfaces 500 is suppressed, and the joining can be performed extremely well.

[0087] The gas inductor 4b of the nozzle A3 can rotate in the circumferential direction, and the angle in the circumferential direction can be adjusted by rotating the flow dividing member 3b. This makes it possible to align the non-heated area a1, which is generated by dividing the gas flow in two directions, with the pressure-welded surface of the pressure-welded material. The gas inductor 4b can also be moved forward and backward by rotating it to change the screwing position of the lower screw tube portion 42b, so that the distance from the fire hole 180 can be adjusted when necessary.

[0088] Next, the structure of a fourth nozzle A4 according to the present invention will be described with reference to FIG. The fourth nozzle A4 has a structure in which a flow diverting member 3c is integrally molded so as to cross the fire hole 20 in the diametrical direction, for example in the above-mentioned nozzle A1 in which the tip member 2 is integral, and the cross-sectional shape of the flow diverting member 3c is rectangular.

[0089] According to the nozzle A4, the gas flow passing through the fire hole 20 is divided into two directions, upper and lower, so that a non-heated area of ​​a specified width can be formed. In this embodiment, the flow diverting member 3c is provided at the fire hole (reference number omitted), and during heating, the flow diverting member 3c is heated by the flame, but since the tip member (reference number omitted) is made of titanium, which has excellent fire resistance, the flow diverting member 3c also has excellent fire resistance, and even if a flashback occurs, damage to the flow diverting member 3c can be prevented.

[0090] Furthermore, the structure of the fifth nozzle A5 according to the present invention will be described with reference to Figs. The fifth nozzle A5, for example, in the above nozzle A1 where the tip member 2 is an integrated type nozzle, has a groove 182 formed in the tip of the tip member 2d of the nozzle base 10d in the diameter direction of the fire hole 181. Then, a titanium pin-shaped flow diverter member 3d with a circular cross section and a predetermined length is fitted into this groove 182 and hammered in and fixed.

[0091] The nozzle A5 can divide the gas flow passing through the fire hole 181 into two directions, upper and lower, to form a non-heated area with a specified width. In this embodiment, the flow diverter member 3d is provided in the fire hole 181, and during heating, the flow diverter member 3d is heated by the flame. However, since the flow diverter member 3d is made of titanium, which has excellent fire resistance, damage to the flow diverter member 3d can be prevented even if a backfire occurs.

[0092] In addition, the above-mentioned nozzles A2, A3, A4, and A5 can be incorporated into the heating torch 9 and used in the same way as the above-mentioned nozzle 1.When pressure welding the pressure welding materials 51 and 52, even if a standard flame using propane gas or the like as a fuel gas is used from the initial heating, the standard flames F1 and F2 do not directly heat the pressure welding surface 500 in the non-heated area a1, so that the formation of an oxide film on the pressure welding surface 500 can be prevented without using a reducing agent.

[0093] The terms and expressions used in the present specification and claims are merely for explanatory purposes and are not limiting in any way, and are not intended to exclude terms and expressions equivalent to the features described in the present specification and claims and parts thereof. In addition, it goes without saying that various modifications are possible within the scope of the technical idea of ​​the present invention. [Explanation of symbols]

[0094] A1 First crater 10 Crater base 100 space 1 Base member 11 Lower threaded pipe section 12 Flange 13 Upper threaded pipe section 14 Tapered hole 15 Press-fit hole 2. Top material 20 fire pits 21 Threaded pipe section 3 Diverting member 4 Gas Derivatives 40 Neck 41 Guidance part 43 Communication hole 400 vents 45 Gas supply hole A2 Second Crater 10a Crater base 100a space 11a Lower threaded pipe section 12a Flange part 17a screw hole 18a Upper pipe section 180 fire pit 19 Screw hole 190 Setscrew 4a Gas Derivatives 40a neck 41a Guidance part 42a Lower threaded pipe section 400 Ventilation 43a Communication hole 44a Engagement recess 45a Gas supply hole 450 Gas outlet 47 Through hole 3a Diverter A3 Third crater 4b Gas Derivatives 40b Neck 41b Guidance part 42b Lower threaded pipe section 400 Ventilation 43b Communication hole 44b Engagement recess 45b Gas supply hole 450 Gas outlet 3b Diversion member A4 Fourth Crater 3c Diversion member A5 Fifth Crater 182 Groove 3d Diverter 9 Heating Torch 90 Gas introduction pipe 91 Branch Pipe 92, 93 Burner tube 94 Mounting tube 51, 52 Pressure welding material 500 Pressure contact surface A0 Crater mouth

Claims

1. A hollow crater base having a fire hole at its tip; and a flow dividing member that is provided in the vicinity of the fire hole of the fire hole base so as to cross the fire hole and divides the gas flow passing through the fire hole into two directions to form a non-heated region with a predetermined width. crater.

2. The flow dividing member is provided at a predetermined distance from the tip of the fire hole toward the inside of the fire hole base. The nozzle according to claim 1.

3. The burner base has a base member and a tip member attached to the base member and provided with the fire hole, The flow dividing member is provided rotatably in a direction intersecting with the axis direction while maintaining a state in which the flow dividing member crosses the fire hole. A nozzle according to claim 1 or 2.

4. The burner base body has a base member and a tip member rotatably attached to the base member and provided with the burner hole. A nozzle according to claim 1 or 2.

5. A gas guide portion is provided inside the burner base, which introduces combustible gas into the burner base and cooperates with the burner base to guide the combustible gas to the burn hole, and the flow dividing member is provided at the tip of the gas guide portion so as to cross the gas outlet leading to the burn hole. The nozzle according to claim 1.

6. The gas guide portion is provided separately from the nozzle base, is rotatable in a circumferential direction relative to the nozzle base, and is fixable at a predetermined position. The nozzle according to claim 5.

7. The tip of the gas guide portion is formed in a gear shape that forms a gas passage between the tip of the gas guide portion and the nozzle base, and each tooth of the gear is arranged to draw a spiral over the entire length of the gas guide portion in the axial direction.

7. The nozzle according to claim 5 or 6.

8. Burner tubes provided opposite to each other; The burner tube is provided with a flow dividing member that crosses the fire hole, and is attached so that the fire hole faces the center of the inside of each burner tube and the gas flow passing through the fire hole is divided into two directions to form a non-heated area with a predetermined width, and the flow dividing member is provided with a plurality of fire holes that are provided so that the length direction is approximately parallel to the center line along the longitudinal direction of the burner tube. Heating torch.

9. The method includes a step of dividing the gas flow passing through the flame hole of the burner into two directions to form a non-heated area with a predetermined width, and heating the non-heated area so that it overlaps with the pressure-welded surface of the pressure-welded material. Gas pressure welding method.

10. The heating is performed with a standard flame. The gas pressure welding method according to claim 9.

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