JP6713686B2 - nozzle - Google Patents

Description

The present invention relates to a nozzle, and more particularly to a one-fluid nozzle that can spray ultrafine particles while having a simple structure that can reduce the generation of coarse particles.

Nozzles for fluid ejection are used for various purposes such as cooling and cleaning. As a method of atomizing droplets in this type of nozzle, a method of generating a swirling flow by a swirling means provided inside the nozzle to atomize the droplet, and a method of colliding a straight flow from the nozzle with a collision pin projecting from the outer surface of the nozzle There is a method of atomizing. The former swirl-type nozzle has a smaller foreign matter passage diameter inside the nozzle and is more likely to be clogged than a collision-type nozzle having the same pressure and the same spray amount. Furthermore, if the injection holes are made large in order to increase the amount of spray per nozzle, the particle size of the mist also increases proportionally, so the injection holes cannot be made large. Therefore, when the total amount of spray required for cooling is large, the number of nozzles is large, which increases equipment costs and requires an installation space. On the other hand, in the latter collision type nozzle, even if the injection hole is made large and the spray amount is increased, it is possible to generate a mist having a fine particle diameter. In addition, the foreign matter passage diameter is larger than that of the swirl type nozzle. From the above points, the latter impingement type nozzle is preferable for applications such as intake cooling of a gas turbine of a power plant where the complete evaporation of fog is important and the installation space of the nozzle is limited.

As a nozzle that collides with a collision pin of this type, for example, US Pat. No. 7,320,443 (Patent Document 1) provides a collision pin type one-fluid nozzle shown in FIG. In the nozzle 100, the tip end of the inner cylinder 120 is fixedly housed in the ejection side wall 110a of the outer cylinder 110 of the nozzle body 101, one end of the hollow portion of the inner cylinder 120 serves as an injection port 122, and the other end of the hollow portion. An inflow port 123 that expands in a taper shape is provided. The base portion 130a of the separate J-shaped collision pin 130 is embedded from the outer surface of the tip of the outer cylinder 110 of the nozzle body 101, and the collision surface 130b at the other end is arranged so as to face the injection port 122, and the liquid ejected from the injection port 122 is ejected. To collide with the collision surface 130b to atomize and spray.

Further, JP-A-9-94487 (Patent Document 2) provides a pin collision type nozzle shown in FIGS. 7(A) to 7(C). In the nozzle 200, a shaft member 230 is adhered and fixed to a concave portion provided at the tip of a pin 220 projecting in a separate J shape from the outer peripheral portion of the jet side end surface 211 of the central nozzle body 210, and the shaft member 230 The lower end is an inclined collision surface 232. A throttle channel 241 at the center of the nozzle tip 240 is located at the central inner end of a conical injection hole 212 provided at the center of the ejection side end surface 211 of the nozzle body 210. The center line of the throttle channel 241 is aligned with the center of the opposing inclined collision surface 232. The entire J-shaped pin 220 including the vertical frame portion (arm portion 220a) has a circular cross section as shown in FIG. 7B.
In the nozzle 200 of Patent Document 2, a water droplet diffused from the throttle channel 241 of the nozzle body 210 to the ejection hole 212 and ejected collides with the opposing inclined collision surface 232 to atomize it.

US Pat. No. 7,320,443 JP, 9-94487, A

In the collision type nozzles of Patent Documents 1 and 2, since a straight flow is made to collide with the collision pin to atomize it, if the injection hole of the straight flow and the center axis of the collision surface of the collision pin are misaligned, they will not be atomized well, and the solid difference Is difficult to manufacture because it will be large. Further, there is a problem that the collided mist easily adheres to the vertical frame portion (arm portion) of the collision pin and the ejection side end surface of the nozzle body to generate coarse particles. In particular, when the collision surface of Patent Document 2 is inclined, the central axis is likely to shift.

Further, in the collision type nozzles of Patent Documents 1 and 2, the nozzle body and the J-shaped collision frame are separate bodies,
Since the nozzle is inserted and fixed in the nozzle body, there is a problem that the material cost and the manufacturing cost are increased and the nozzle becomes expensive.

The present invention has been made in view of the problem of the collision type nozzle, and in the collision type nozzle,
It is an object of the present invention to provide a nozzle that makes it difficult for water droplets to adhere to the collision frame and the jet side end surface of the nozzle body, prevents the generation of coarse particles, and promotes atomization of water droplets contained in spray. ..

In order to solve the above problems, the present invention is a one-fluid nozzle in which a J-shaped collision frame is integrally provided from the outer surface of the injection side wall of a cylindrical nozzle body,
The injection side wall formed of a flat plate-shaped closing wall is provided at one end of the nozzle body, and an injection hole formed of a straight hole is provided in the center axis of the injection side wall, and a cross section surrounded by a flat inner surface and an outer peripheral wall of the injection side wall. A straight passage having a circular shape and a constant inner diameter is provided, and the liquid is sprayed from the straight passage through the injection hole as a straight rod flow, and,
A pin hole is provided in a horizontal frame portion projecting from the protruding side tip of the vertical frame portion of the J-shaped collision frame across the central axis, and a collision pin is fitted in the pin hole to face the injection hole. The projection side, the projection side is sharpened into a truncated cone shape, and a collision surface formed of a circular flat surface having an outer peripheral edge as an edge is provided at the tip of the collision pin with which the rectilinear rod flow collides, and The vertical frame portion of the collision frame has a triangular cross section in which the inner surface on the collision pin side is inclined at an acute angle.

As described above, the collision surface of the collision pin is a circular flat surface which is different from the reference document 2 and is orthogonal to the central axis of the straight rod flow, and the outer peripheral edge of the collision surface is an edge, preferably R0.01 or less. It has a sharp edge. In this way, when the outer peripheral edge of the collision surface is made a sharp edge, the transparent rod flow that collided with the collision surface is immediately separated by the edge, the liquid film becomes thin, and there is no decrease in the flow velocity due to wall resistance, so miniaturization is required. Can be promoted.
The collision pin is fixed to a pin hole provided in a lateral frame portion of the collision frame by press fitting, adhesion, caulking or the like.

Furthermore, even if water droplets that collide with the collision surface and the edge try to adhere to the inner surface of the vertical frame portion of the opposing collision frame, since the inner surface of the vertical frame portion is a triangle inclined at an acute angle, the water droplets do not adhere. The water flows outward along the slopes on both sides. Therefore, it is possible to prevent water droplets from adhering to the inner surface of the vertical frame portion, and the adhering water droplets from being scattered together with the scattering water droplets to generate coarse particles.
It is preferable that the vertical frame portion of the collision frame has a triangular cross-section with an inner surface inclined at an acute angle, an outer surface having an arc shape, and a so-called teardrop-shaped cross section. This teardrop-shaped cross-section has an inner-outer dimension of 4 to 3 mm, preferably 3 mm, and a dimension in the front-rear direction orthogonal to the inner-outer direction of 2.5 to 2 mm. I try not to attach it. Even if the collision pin is made thin in this way, it is integrated with the nozzle body, so that durability and pressure resistance can be improved as compared with the case where the collision pin is fixed to the nozzle body separately.

In order to prevent water droplets from splashing on the collision frame, the protrusion (height) of the vertical frame from the nozzle body is increased to prevent water droplets from easily adhering to the horizontal frame of the collision frame. It is preferable to make the inner peripheral surface bent from the portion to the lateral frame portion as small as R0.5.

The pin hole of the collision frame and the injection hole of the nozzle body are coaxial, the diameter of the collision surface of the collision pin is within a range of 100% to 115% with respect to the diameter of the injection hole, and the straight flow path is formed. It is preferable that an edge is provided at the peripheral edge of the inflow port of the communicating injection hole.

As described above, when the circular flat surface at the tip of the collision pin is brought close to the injection hole and the areas thereof are made substantially equal to each other and the straight rod flow collides with the circular flat surface from the injection hole, the injection liquid collides nearly 100%. It collides with the circular flat surface at the tip of the pin, and it is possible to surely atomize the droplet.
When the area of the collision surface of the collision pin is within the range of 100% to 115% with respect to the cross-sectional area of the injection hole, the liquid film becomes thick and the particle diameter after the membranous splitting is 100% or less. This is because the spray becomes larger, the spread of the spray becomes narrower, and the cooling efficiency such as intake air cooling decreases.
On the other hand, when it exceeds 115%, the spray spreads in the direction of 180°, the straightness is lost, and water droplets easily adhere to the nozzle body.
Further, when the dimension between the collision surface of the collision pin and the tip of the injection hole is within the range of 0.1 mm to 1.0 mm, when the distance is less than 0.1 mm, the gap between the injection hole and the collision surface of the collision pin. Becomes an orifice, the spray pattern changes greatly, and the foreign particle passage diameter also decreases. If it exceeds 1.0 mm, it becomes more difficult to center the injection hole and the collision surface as the distance increases.
For example, when the diameter of the injection hole is 0.18 mm, the diameter of the circular flat surface is 0.18 mm to 0.2 mm. Further, the inclination angle of the truncated cone of the collision pin is preferably 90 degrees or less.

In addition, as described above, the peripheral edge of the injection hole communicating with the straight flow passage is an edge without a radius, and the diameter of the straight flow passage is four times or more the diameter of the injection hole. Is preferred.
As described above, the edge of the inlet of the injection hole is used as an edge, so that the water flow flowing from the straight flow path into the injection hole flows into the injection hole while separating from the inner peripheral surface of the injection hole. The transparent rod flow is generated by eliminating the contact friction with the water flow so as not to generate turbulence on the outer surface. Furthermore, by making the collision surface a sharp edge, after the transparent rod flow collides with the collision surface, it immediately separates at the edge, the liquid film becomes thin, and there is no decrease in flow velocity due to wall surface resistance, so miniaturization is promoted. it can.

It is preferable that the integral nozzle body and the collision frame are made of stainless steel, and the collision pin is made of ceramic. The nozzle body and the collision frame may be made of another metal or ceramic, and the collision pin may be made of a super hard material such as stainless steel, ruby, sapphire.

As described above, the nozzle of the present invention is produced by precision casting stainless steel to continuously process a cylindrical nozzle body and a collision frame, enhance the strength and pressure resistance of the nozzle, and use it as a nozzle for high-pressure spraying. There is. That is, in the nozzle of the present invention, the vertical frame portion of the J-shaped collision frame is projected from the outer end surface of the ejection side wall of the nozzle body, and the lateral frame portion for projecting the collision pin is cantilevered. The collision frame is made of stainless steel that is continuous with the nozzle body, and the collision pin itself is also made of strong ceramic, so the collision frame and the collision pin are stable even when a high-pressure straight rod flow collides. It has pressure resistance to hold the posture.
For the purpose of improving atomization performance and increasing the amount of spray, the spray pressure may be used at a high pressure of 10 MPa or more. In this case, wear of the collision pin and the injection hole becomes a problem. The collision pin is more likely to wear than the injection hole, and a material with excellent wear resistance is preferable, but ruby etc. has a problem that it is difficult to process, but ceramic is excellent in wear resistance and easy to process, and it is low cost. Can be manufactured.

Further, the surface of the collision frame made of stainless steel is polished to be a smooth surface, and the inner surface of the injection side wall of the nozzle body is polished to make the closed surface of the straight flow passage a smooth surface, and The edge of the inlet is a sharp edge.
If the surface of the collision frame is made smooth as described above, water droplets that collide with the collision pins and scatter are less likely to adhere to the collision frame, and also water droplets that collide with the closed surface of the straight flow passage in the nozzle body. Can be hardened.

Further, in the nozzle of the present invention, it is preferable that the liquid pressure to be supplied is 5.0 to 13 MPa and the average particle diameter of the liquid to be sprayed is 20 μm or less.
The liquid pressure is preferably set to a high pressure of 6 to 13 MPa, and the collision pressure on the collision pin is increased to further reduce the average particle diameter to 17 μm or less.

The other end of the cylindrical portion of the nozzle body is an opening for inserting a strainer, the front portion of the strainer made of a porous material is fitted into the cylindrical portion, and is projected into the liquid supply pipe connecting the rear portion of the strainer. The outer peripheral surface of the rear portion is formed into a petal shape in which a plurality of arc portions are continuous, and a straight liquid passage of a front end opening is provided along the central axis of the strainer, and a liquid is introduced from the front end of the straight liquid passage to the injection hole. Is preferably introduced.

The strainer made of a porous material has three-dimensionally continuous pores, and the porosity is in the range of 40 to 80%.
In this way, if a strainer is installed on the inflow side of the nozzle and foreign matter in the liquid is captured and removed by the strainer before flowing into the injection hole of the nozzle body, it is possible to reliably prevent the injection hole from being clogged with foreign matter. it can.

The nozzle of the present invention can be suitably used for cooling intake air because the average particle diameter of the sprayed droplets is 20 μm or less.

As described above, in the nozzle of the present invention, since the outer peripheral edge of the collision pin with which the straight rod flow injected from the injection hole of the nozzle main body collides has a sharp edge, the straight rod flow colliding with the collision surface is immediately moved to the edge. The liquid film becomes thinner and the liquid film becomes thinner, and there is no reduction in the flow velocity due to wall surface resistance, so miniaturization can be promoted. Moreover, even if water droplets that collide with and collide with the collision surface and the edge of the collision pin try to adhere to the inner surface of the vertical frame portion of the opposing collision frame, the inner surface of the vertical frame portion is a triangle inclined at an acute angle. It flows outward along the slopes on both sides without adhering. Therefore, it is possible to prevent water droplets from adhering to the inner surface of the vertical frame portion, and the adhering water droplets from being scattered together with the scattering water droplets to generate coarse particles. Therefore, atomization of spray can be promoted and generation of coarse particles can be suppressed. Further, since the nozzle main body and the J-shaped collision frame projecting from the nozzle main body are integrally provided, the strength and pressure resistance are excellent, and the high pressure is high. It becomes a nozzle for spraying. Moreover, since it is a one-fluid nozzle, no compressor is required and the piping can be simplified. Further, although it is a one-fluid nozzle, it can spray ultrafine particles having an average particle diameter of 20 μm or less, and can cool an object without wetting it with water droplets, and is suitably used as a nozzle for cooling intake air, for example.

The nozzle with a strainer of embodiment of this invention is shown, (A) is a front view, (B) is sectional drawing of a nozzle, (C) is a CC arrow line view of (A). (A) is a cross-sectional view of an essential part of the nozzle, and (B) is an explanatory view showing a state in which a straight rod flow collides with a collision pin from an injection hole of a nozzle body. It is drawing which shows the cross-sectional shape of the vertical frame part of the collision frame of the said nozzle. (A) is a sectional view of the nozzle with a strainer, (B) is a side view of the strainer, and (C) is a partial sectional view of the strainer. It is sectional drawing which shows the state which attached the said nozzle with a strainer to the liquid supply pipe. It is sectional drawing which shows a prior art example. (A)-(C) is drawing which shows another prior art example.

Hereinafter, embodiments of a nozzle of the present invention will be described in detail with reference to the drawings.
The strainer-equipped nozzle 1 of the embodiment shown in FIGS. 1 to 5 is made of a stainless steel one-fluid nozzle, and a strainer 30 made of a resin-made porous material is screwed into the nozzle 1 to be assembled. With 30 assembled, a small and lightweight nozzle having a total length L1 of 20 to 30 mm is used.

As shown in FIG. 1(B), the nozzle 1 has a J-shaped collision frame 3 protruding from the outer surface of an injection side wall 2a which is a closed wall at one end of a nozzle body 2 having a simple cylindrical shape. The nozzle body 2 and the collision frame 3 are one-fluid nozzles integrally formed by precision casting stainless steel. A collision pin 4 made of ceramic is pushed into and fixed to the collision frame 3 so as to project.

The injection side wall 2a formed of a flat plate-shaped closed wall is provided at one end of the nozzle main body 2, the injection hole 10 formed of a straight hole is provided on the central axis Po of the injection side wall 2a, and the flat inner surface 2b and outer periphery of the injection side wall 2a are provided. It has a straight passage 11 surrounded by a wall 2c and having a circular cross section and a constant inner diameter. A peripheral edge 10e of the inflow port 10a of the injection hole 10 opening to the flat inner surface 2b is a sharp edge.

The inflow port 10a of the jet hole 10 is communicated with the straight flow passage 11, and the liquid is jetted from the straight flow passage 11 through the jet hole 10 as a straight rod flow. The diameter of the injection hole 10 is 0.1 to 1.0 mm (0.18 mm in the present embodiment), and the length of the injection hole 10 is 1 mm in the present embodiment to ensure that the liquid is a straight rod flow from the injection hole 10. I am trying to be sprayed. The diameter of the straight flow passage 11 is φ0.4 to 4.4 mm, which is four times that of the injection hole 10.

The J-shaped collision frame 3 has a shape including a vertical frame portion 3a protruding from the tip end surface of the ejection side wall 2a and a horizontal frame portion 3b protruding from the tip end of the vertical frame portion 3a across the central axis Po. is there. A pin hole 3h is provided at the position of the central axis Po of the lateral frame portion 3b, and the collision pin 4 is fitted and fixed in the pin hole 3h so as to project toward the injection hole 10.

The pin hole 3h is a tapered hole that reduces its diameter toward the injection hole 10, while the collision pin 4 has a diameter that decreases toward the collision side of the tip, and the tip 4a has a truncated cone shape with a steep inclination angle. A collision surface 5 formed of a circular flat surface is provided at the tip. The radius R1 of the outer peripheral edge of the circular collision surface 5 is a sharp edge of 0.01 or less.

The diameter of the collision surface 5 at the tip of the collision pin 4 is in the range of 100% to 115% with respect to the diameter of the opposing injection hole 10, and the dimension L3 between the collision surface 5 and the tip of the injection hole 10 is 0. The range is from 0.1 mm to 1.0 mm. In this embodiment, the dimension L4 between the central axis of the injection hole 10 and the inner surface of the vertical frame portion 3a is 3.5 mm, and the dimension L3 is 0.6 mm.

The vertical frame portion 3a of the collision frame 3 has a triangular cross section in which the inner surface facing the collision pin 4 is inclined at an acute angle, and the outer surface on the opposite side has an arc shape, which is a so-called teardrop-shaped cross section. The radius R2 of the acute-angled apex on the inner surface side is 0.2 or less, and the radius R3 of the arc on the opposite side is about 1. As shown in FIG. 3, the vertical width 3a of the vertical frame portion 3a is about 3 mm, and the front-rear width S2 in the orthogonal direction is about 2 mm so that the water droplets that collide do not adhere to it as much as possible.
Further, the protrusion amount (height L2) of the vertical frame portion 3a is set to a height of 3 mm or more, which makes it difficult for water droplets colliding with the collision surface 5 to adhere to the horizontal frame portion 3b. In the present embodiment, L3 is 0.6 mm, L4 is 3.5 mm, and L2 is 4.2 mm. Further, the radius R4 of the inner peripheral portion that bends from the vertical frame portion 3a to the horizontal frame portion 3b is set to 0.5 to be small to make it difficult for water droplets to adhere to the inner peripheral surface of this curved portion.

As shown in FIGS. 1(A) and 1(B), in a cylindrical nozzle body 2, a front portion 2f on the injection side has a large diameter, a rear portion 2g has a small diameter, and an outer peripheral surface of the large diameter portion of the front portion 2f has a diameter of 6 mm. It has a rectangular shape and an arc portion is provided at the boundary of each side. A screw 2d is provided on the outer peripheral surface of the rear portion 2g having a small diameter. The hollow portion of the cylindrical nozzle body 2 has a straight flow passage 11 having the same inner diameter, the rear end has an opening 2s, and the front portion 30a of the strainer 30 is fitted therein. The front end of the rectilinear flow path 11 having a circular cross section formed of a hollow portion of the nozzle body 2 is closed by a flat inner surface 2e of the injection side wall 2a. The inflow port 10a of the injection hole 10 is located at the center of the flat inner surface 2e serving as the closed surface. The flat inner surface 2e serving as the closed surface is polished so that the water flowing from the straight flow passage 11 into the injection hole 10 is well cut off, and the periphery of the inflow port 10a of the injection hole is a sharp edge 10e. As a result, the water flow flowing from the straight flow path 11 into the injection hole 10 flows into the injection hole while being separated from the inner peripheral surface of the injection hole 10, and the contact friction with the inner peripheral surface of the injection hole 10 is eliminated to the outer surface of the water flow. A transparent rod flow is generated without causing turbulence.

In the nozzle 1, the liquid pressure supplied is 5.0 to 13 MPa, preferably 6 to 13 MPa, the spray flow rate is 6 to 16 L/hr when the liquid pressure is 6 MPa, and the average particle diameter of the sprayed liquid is 20 μm or less, It is preferably 17 μm or less.

As shown in FIGS. 1 and 4, the front portion 30a of the cylindrical strainer 30 is internally fitted and assembled through the opening 2s at the rear end of the rectilinear flow path 11 of the nozzle body 2.

The strainer 30 is made of a resin material having three-dimensionally continuous pores 35 as shown in FIG. 4C, and the porosity is 40 to 80%. The strainer 30 has a front portion 30a and a rear portion 30b which are continuous with each other, and a liquid passage 33 which is a central hole is provided from a front end of the front portion 30a to an intermediate portion of the rear portion 30b. The liquid passage 33 is configured to open to the straight flow passage 11 and to flow from the straight flow passage 11 to the injection hole 10.
In addition, as shown in FIG. 4B, the outer peripheral surface of the rear portion 30b of the strainer 30 has four arcuate portions 32 protruding to form a petal shape to increase the surface area and increase the amount of liquid absorbed by the strainer 30.

As shown in FIG. 5, the nozzle 1 to which the strainer 30 is attached is attached by screwing the screw 2d of the nozzle body 2 into the screw hole 40h provided in the liquid supply pipe 40, and the rear portion 30b of the strainer 30 inside the liquid supply pipe 40. Overhangs. By forming the outer peripheral surface of the rear portion 30b of the strainer 30 projecting into the liquid supply pipe 40 into a petal shape, the area for absorbing the liquid Q flowing in the liquid supply pipe 40 is increased.

In the nozzle 1 provided with the strainer 30 of the above-described embodiment, the liquid Q supplied from the liquid supply pipe 40 is introduced through the strainer 30, and the strainer 30 captures foreign substances mixed in the liquid Q. The liquid that has passed through the strainer 30 flows into the injection hole 10 through the straight flow passage 11 in the nozzle body 2 of the nozzle 1, and from the injection hole 10 that is a small hole, as shown in FIG. Is jetted, and collides with the collision surface 5 at the tip of the collision pin 4 at the facing position.

At that time, since the diameter of the injection hole 10 is as small as 0.1 to 1.0 mm (0.18 mm in this embodiment), the pressure of the liquid passing through the injection hole 10 is increased and the injection pressure is increased. The straight rod flow Qs is injected and collides with the collision surface 5. Since the collision surface 5 is arranged in the same straight line as the ejection hole 10 and has the same area, the entire amount of the straight-ahead rod flow ejected from the ejection hole 10 collides with the collision surface 5 and all droplets are miniaturized. Being scattered, it scatters outward.
As described above, by colliding the high-pressure straight rod flow with the collision pin, it is possible to spray with an average particle diameter of 17 μm or less.

Since the collision type one-fluid nozzle 1 has a sharp edge at the peripheral edge of the collision surface 5 of the collision pin 4, the water droplets that collide with the nozzle 1 are well cut, and the generation of coarse particles can be suppressed. Further, even if the water droplets that have collided with the collision surface 5 are scattered toward the collision frame 3, the vertical frame portion 3a of the collision frame 3 has a teardrop-shaped cross section and the collision pin side has an acute angle. Also, the generation of coarse particles can be suppressed, and atomization of spray can be achieved.
Moreover, since water flows into the nozzle 1 through the strainer, foreign matter in the water can be removed in advance, and even if the injection hole 10 of the nozzle 1 is a fine hole, the occurrence of clogging can be prevented.
From the above points, the nozzle with a strainer is preferably used as an intake air cooling nozzle of a gas turbine of a power plant.

1 Nozzle 2 Nozzle Main Body 3 Collision Frame 3a Vertical Frame 3b Horizontal Frame 3h Pin Hole 4 Collision Pin 5 Collision Surface 10 Injection Hole 10e Edge 11 Straight Flow Path 30 Strainer Q Liquid Qs Straight Straight Flow

Claims (3)

A one-fluid nozzle in which a J-shaped collision frame is integrally provided from the outer surface of the injection side wall of the cylindrical nozzle body,
The injection side wall formed of a flat plate-shaped closing wall is provided at one end of the nozzle body, and an injection hole formed of a straight hole is provided in the center axis of the injection side wall, and a cross section surrounded by a flat inner surface and an outer peripheral wall of the injection side wall. A straight passage having a circular shape and a constant inner diameter is provided, and the liquid is sprayed from the straight passage through the injection hole as a straight rod flow, and,
A pin hole is provided in a horizontal frame portion projecting from the protruding side tip of the vertical frame portion of the J-shaped collision frame across the central axis, and a collision pin is fitted in the pin hole to face the injection hole. The projection side, the projection side is sharpened into a truncated cone shape, and a collision surface formed of a circular flat surface having an outer peripheral edge as an edge is provided at the tip of the collision pin with which the rectilinear rod flow collides, and The nozzle is characterized in that the vertical frame portion of the collision frame has a triangular cross section in which the inner surface on the collision pin side is inclined at an acute angle. The pin hole of the collision frame and the injection hole of the nozzle body are coaxial, the diameter of the collision surface of the collision pin is within a range of 100% to 115% with respect to the diameter of the injection hole, and the straight flow path is formed. The nozzle according to claim 1, wherein an edge is provided on a peripheral edge of an inflow port of the injection hole which communicates with each other. The nozzle according to claim 1 or 2, wherein the nozzle body and the collision frame provided integrally are made of stainless steel, and the collision pin is made of ceramic.

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