JP2009179846A - Thermal spraying apparatus and member of spray port - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thermal spraying apparatus which prevents a thermal spray material from depositing on an inner part of the thermal spraying apparatus and the deposited thermal spray material from causing spitting, even when a thermal spray material with a small particle size is used. <P>SOLUTION: A section 104 for supplying the thermal spray material is arranged at such a position that the thermal spray material supplied into a combustion gas from the section 104 for supplying the thermal spray material is sprayed from a spray port 103a to the outside of the thermal spray apparatus 100 before the thermal spray material melts. Thereby, the thermal spray material is sprayed before being changed to a molten state of which the thermal spray material easily deposits on the inner part of the thermal spraying apparatus, which prevents the thermal spray material from depositing in the thermal spraying apparatus and consequently from causing spitting. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a thermal spraying apparatus that sprays a thermal spray material onto a thermal spray material, a spraying apparatus that supplies a thermal spray material that can prevent the thermal spray material from adhering to the inside of the thermal spraying apparatus, and a thermal spraying apparatus that injects combustion gas It is related with the structure of the front-end | tip part.

  Conventionally, a high-speed gas sprayer or a plasma gas sprayer has been used to obtain a dense sprayed coating excellent in wear resistance and corrosion resistance.

  For example, US Pat. No. 5,271,965 describes an example of a high-speed gas sprayer. A high-speed gas sprayer commercially available based on this patent is shown in FIG. This high-speed gas sprayer is roughly divided into a combustion chamber tail plug 1 disposed at the rear end, a combustion chamber 2 in front of the spraying direction, and a spray nozzle 5 connected to the combustion chamber 2.

  The fuel chamber tail plug 1 is provided with a fuel supply hole 7 for supplying fuel such as kerosene or kerosene at a high speed forward in the spraying direction and an oxygen supply hole 8 for supplying oxygen gas at a high speed forward in the spraying direction.

  The combustion chamber 2 to which the combustion chamber tail plug 1 is attached is formed in a cylindrical shape, and a laval type nozzle 3 having a shape that gradually expands after the diameter is reduced to a small diameter is connected to the spray nozzle 5. Is formed.

  A thermal spray nozzle 5 connected to the combustion chamber 2 via a Laval nozzle 3 is a copper tube having an inner diameter of about 11 mm and a length of about 10 cm to 20 cm, and is water-cooled from the outside. A thermal spray material supply unit 4 for supplying the thermal spray material is disposed on the Laval nozzle 3 side of the thermal spray nozzle 5. As the thermal spray material, a material obtained by adding a material in accordance with required properties such as wear resistance to a Ni-based, Ni-Cr-based or Co-based alloy is used.

  When thermal spraying is performed, the fuel and oxygen supplied from the kerosene or kerosene supply hole 7 and oxygen supply hole 8 installed in the combustion chamber tail plug 1 are first burned in the combustion chamber 2. The combustion gas in the combustion chamber 2 at this time has a pressure of about 0.7 MPa and a combustion temperature of about 3000 ° C. Then, the combustion gas is fed into the Laval nozzle, and when passing through the Laval nozzle 3, it is accelerated from the sonic speed to the supersonic speed (about Mach 2.5) and supplied to the thermal spray nozzle 5. And in the connection part of the Laval type nozzle 3 and the thermal spray nozzle 5, a thermal spray material is blown from the thermal spray material supply part 4 with respect to the accelerated combustion gas. The thermal spray material is accelerated and heated by the combustion gas. The combustion gas and the thermal spray material are rectified by passing through the thermal spray nozzle 5, and are focused from the tip of the thermal spray nozzle 5 with improved convergence. Thereby, the thermal spray material can be sprayed at a very high speed and sprayed onto the thermal spray material.

According to such a thermal spraying machine, since the thermal spray material can be sprayed at high speed, it is possible to form a dense thermal spray coating excellent in adhesion to the thermal spray material.
US Pat. No. 5,271,965 JP 2003-129212 A

  When performing thermal spraying using the high-speed gas sprayer as described above, a particulate thermal spray material having a particle size of 30 μm to 40 μm is usually used as the thermal spray material.

  However, when a thermal spray coating is formed on a material to be sprayed using a thermal spray material having such a particle size, there is a problem that pores of 1% to 3% in terms of area ratio are generated in the thermal spray coating. When pores are present in the thermal spray coating, the denseness of the thermal spray coating is reduced, and wear resistance, coating strength, adhesion to the sprayed material, and the like are reduced as compared with the case where pores are not present. Furthermore, if pores that penetrate into the inside of the coating have been formed, the corrosion resistance will also be reduced.

Therefore, by performing thermal spraying using a thermal spray material having a particle size smaller than the conventional particle size, the proportion of the thermal spray material in the thermal spray coating formed on the thermal spray material is increased, and pores are reduced. Consideration is being made. FIG. 2 shows the tip of the thermal spray nozzle when WC-Co particles are supplied as a thermal spray material when kerosene is supplied at a flow rate of 15.9 liter / h and oxygen is supplied at a flow rate of 48 m ³ / h for combustion. The graph of the result of having measured the speed | velocity | rate of the particle | grain in the position of 300 mm of the downstream direction of a combustion gas flow from is shown. As can be seen from the relationship between the particle size of the sprayed particles and the velocity of the particles shown in FIG. 2, the effect of increasing the velocity of the particles can be obtained by reducing the particle size. If the particle velocity is higher, the particles deform more flat when the particles collide with the sprayed material, and a denser film can be obtained. Therefore, it is considered that a denser film can be obtained if a thermal spray material having a particle size smaller than the conventional particle size can be sprayed.

  However, in the conventional high-speed gas sprayer, there is a problem that a sprayed material blown into the spray nozzle 5 is brought into contact with the inner wall of the spray nozzle 5 which is cooled by water, and adheres and oxidizes. When the thermal spray material adheres to the inner surface, the inner surface of the thermal spray nozzle 5 becomes rough, and further, oxides of the thermal spray material are deposited. FIG. 3 is a sectional view of the thermal spray nozzle 5 in a state where an oxidized thermal spray material adheres to the inner surface.

  Further, the deposited oxidation spray material is peeled off from the inner surface of the spray nozzle 5 and causes a phenomenon called spitting that is injected by the combustion gas. Oxide sprayed material that has peeled off due to spitting will be sprayed onto the sprayed material by the combustion gas, but if it is missing from the sprayed material and becomes pinhole or not missing, it becomes a projection and the quality Since the product is reduced and the product cannot be produced, the thermal spray coating must be re-polished and re-sprayed.

  When spraying is performed using a thermal spray material having a particle size smaller than the conventional particle size, adhesion to the inside of the thermal spraying device and spitting become more prominent. This is because if the spray particles are small, the specific surface area is large, and the particles are excessively heated and are more easily melted than when the particle size is large. This is also apparent from FIG. 4 showing the result of measuring the relationship between the particle size of sprayed particles and the particle temperature under the same conditions as when the relationship between the particle size and particle velocity shown in FIG. 2 is measured. As shown in FIG. 4, when the particle size of the sprayed particles is small, the temperature of the particles becomes very high due to the heat of the combustion gas. As a result, the temperature of the sprayed particles exceeds the temperature suitable for spraying, and the particles are melted. And when a thermal spray particle melts, adhesion to the inside of a thermal spraying apparatus will occur easily.

  As described above, it has been very difficult to spray a spray material having a small particle diameter stably for a long time using the conventional spraying apparatus as shown in FIG. 1 as it is.

  Therefore, not only when using a spray material with a normal particle size as described above, but also when using a fine powder spray material with a small particle size to form a dense spray coating, spitting occurs. There was a need for a high-speed gas sprayer that was unlikely to occur.

  In response to this problem, Patent Document 2 (Japanese Patent Laid-Open No. 2003-129212) describes a thermal spraying machine in which a nozzle for supplying a thermal spray material is arranged on the front side in the thermal spraying direction of the thermal spraying apparatus. The structure of the thermal sprayer is shown in FIG. According to this thermal spraying machine, since the thermal spray material supply nozzle is disposed on the front side in the thermal spraying direction of the thermal spraying apparatus, an effect that spitting is hardly generated is obtained.

  In addition, this thermal sprayer has a step in the middle of a hole through which combustion gas flows, and has an ejection port for ejecting a cylindrical air flow that surrounds the combustion gas at its end face. As a result, the combustion gas can be injected while being surrounded by the cylindrical airflow. The thermal spray material supply nozzle is configured so that the tip of the thermal spray material nozzle protrudes to the inner surface of the hole of the thermal sprayer (on the downstream side of the second hole) to supply the thermal spray material to the inside of the cylindrical airflow. As a result, the thermal spray material is softened and melted inside the cylindrical airflow, and is discharged to the outside of the thermal sprayer, so that the molten thermal spray material adheres to the interior of the thermal sprayer and spitting is less likely to occur. The effect is said to be obtained.

  However, in the case of such a thermal sprayer structure, since the tip of the nozzle for supplying the spray material protrudes to the inner surface of the injection hole, the cylindrical compressed air cuts through the tip of the nozzle, and the air flow Will be disturbed. In addition, the combustion gas is also affected by the turbulence of the airflow, and the turbulence of the airflow occurs. When the turbulence of the air flow of the cylindrical gas occurs, the sprayed particles are prevented from smoothly entering the combustion gas. Thermal spray particles that do not fit in the combustion gas do not travel forward in the spraying direction, but are scattered to the surroundings, damaging the tip of the spray hole of the thermal sprayer or being mixed into the thermal spray coating, reducing the quality of the coating. Cause.

  Further, since the tip of the nozzle protrudes from the inner surface of the hole, it is necessary to separate the tip of the nozzle from the combustion gas so that the nozzle for supplying the sprayed material does not melt due to the heat of the combustion gas. If the tip of the nozzle is away from the combustion gas, the spray material may not be drawn into the combustion gas and may be blown away by the high-speed combustion gas. And when the thermal spray material is a fine powder having a particle size smaller than 10 μm, the kinetic energy is small, so the ratio of being blown off on the surface of the combustion gas is high, the quality of the sprayed material is lowered, the thermal sprayer itself is damaged, This may cause a decrease in yield.

  Because of these problems, the present invention makes it difficult for the sprayed material to adhere to the inside of the spraying device or spitting even when a finely sprayed material having a small particle size is used, and the sprayed material is smoothly put into the combustion gas. It is an object of the present invention to provide a high-speed gas sprayer having a structure that can be introduced into the system.

  The thermal spraying apparatus of the present invention includes a thermal spray nozzle that injects a combustion gas in the thermal spray direction, and a thermal spray material supply unit that supplies the thermal spray material to the combustion gas flowing in the thermal spray nozzle, and the thermal spray material is covered with the combustion gas. A thermal spraying apparatus for spraying a thermal spray material, wherein the thermal spray material supplied from the thermal spray material supply unit is discharged from the spray nozzle at the tip of the thermal spray nozzle before being melted by the heat of the combustion gas. The supply position of the thermal spray material is set.

  Further, a thermal spraying apparatus as another aspect of the present invention includes a thermal spray nozzle that injects combustion gas in the thermal spray direction, and a thermal spray material supply unit that supplies thermal spray material to the combustion gas flowing in the thermal spray nozzle, A thermal spraying apparatus for spraying a thermal spray material on a thermal spray material by combustion gas, wherein the spray material supply position is set to a position within 30 mm from the spray nozzle at the tip of the thermal spray nozzle. Features.

  Further, the spray port member of the present invention is a spray port member attached to the tip of the spray nozzle of a thermal spraying apparatus that sprays the sprayed material onto the sprayed material by the combustion gas sprayed in the spraying direction from the spray nozzle. An inner diameter that is equal to or greater than the inner diameter of the nozzle, communicates with the thermal spray nozzle, and injects the combustion gas supplied from the thermal spray nozzle in the thermal spraying direction, and supplies the thermal spray material to the combustion gas flowing in the injection nozzle A thermal spray material supply unit, and the thermal spray material supply unit positions the thermal spray material supply unit so that the thermal spray material supplied from the thermal spray material supply unit is discharged from the injection port before being melted by the heat of the combustion gas. It is characterized by setting.

  According to the thermal spraying apparatus of the present invention, the thermal spray material supplied to the combustion gas from the thermal spray material supply unit is sprayed to a position where the thermal spray material is discharged from the spray port of the thermal spraying apparatus before being melted by the heat of the combustion gas. Since the supply position of the material supply unit is set, it is possible to prevent the thermal spray material from adhering to the inside of the thermal spray apparatus or causing spitting.

  Further, according to the thermal spraying apparatus of the present invention, even if the thermal spraying material is a particle having a small particle size, it is possible to prevent adhesion and spitting inside the thermal spraying apparatus. A densely deposited film can be formed, and a thermal sprayed film excellent in wear resistance, corrosion resistance, and the like can be obtained.

  Hereinafter, based on this embodiment shown in drawing, the thermal spraying apparatus which concerns on this invention is demonstrated. The thermal spraying apparatus of the present embodiment is a thermal spraying apparatus that sprays a thermal spray material at a high speed toward a thermal sprayed material such as a roll that requires wear resistance, corrosion resistance, etc., and is stable even with a thermal spray material having a small particle size. To enable thermal spraying.

Example 1
FIG. 6 is a cross-sectional view of the high-speed gas spraying apparatus 100 of Example 1 of the present embodiment. The high-speed gas spraying apparatus 100 is roughly divided into a combustion chamber 101 and a spray nozzle 103 arranged in front of the spraying direction.

The combustion chamber 101 is formed in a cylindrical shape having a longitudinal direction in the spraying direction, and the rear end of the combustion chamber 101 is sealed by a combustion chamber tail plug 105 having a fuel supply unit 106 and an oxygen gas supply unit 107. Fuel is supplied from the fuel supply unit 106 and oxygen gas is supplied from the oxygen gas supply unit 107 toward the spray nozzle 103 (hereinafter referred to as “spraying direction”) at high speed. Kerosene or the like is used as the fuel. Flow rate is preferably about 15.5 liters /h~26.5 liters / h of fuel (kerosene), an oxygen flow rate ^{48m 3} / ^h~53m 3 / h is preferably about. A Laval nozzle 102 is formed at a connection portion of the combustion chamber 101 with the thermal spray nozzle 103. The Laval nozzle 102 is a nozzle whose diameter gradually increases after being narrowed down from the diameter of the combustion chamber 101. When a fluid is supplied to the Laval nozzle 102 at a high pressure, the speed of the fluid passing therethrough can be greatly accelerated. Depending on the temperature and pressure of the fluid supplied, the speed can be increased to supersonic speed. .

  The thermal spray nozzle 103 disposed in front of the combustion chamber 101 and the Laval nozzle 102 in the thermal spray direction has the same diameter as the tip of the Laval nozzle 102 of the combustion chamber 101, and is a hollow copper having a constant diameter in the longitudinal direction. It is a tube. The length is preferably about 10 to 20 cm. This thermal spray nozzle 103 rectifies the high-speed combustion gas supplied from the combustion chamber 101 and improves the convergence. For this reason, if the length is shorter than the above length, the rectifying effect and the focusing effect are small, and if the length is too long, the speed of the combustion gas is reduced.

  The tip of the thermal spray nozzle 103 opens to the outside at the tip of the thermal spray apparatus 100, and forms an injection port 103a through which the thermal spray material is ejected from the thermal spray apparatus 100 together with the combustion gas.

  The basic configuration of the combustion chamber 101, the Laval nozzle 102, and the spray nozzle 103 is the same as that of the conventional high-speed gas spray apparatus as shown in FIG.

  Next, the thermal spray material supply unit 104, which is a characteristic part of the thermal spray apparatus 100 of the present embodiment, will be described. The thermal spray material supply unit 104 is disposed on the front end side of the thermal spray nozzle 103 in the thermal spray direction. This thermal spray material supply unit 104 has the same structure as a nozzle used for supplying an ordinary thermal spray material in a conventional thermal spraying apparatus, but a tip portion 104a, which is a spray material supply position, is formed on the inner surface of the thermal spray nozzle 103. Open so that it does not protrude. Further, the thermal spray material supply unit 104 is connected to a thermal spray material supply device (not shown), and the thermal spray material supplied from the thermal spray material supply device moves from the tip 104a of the thermal spray material supply unit 104 at a high speed in the thermal spray direction. Supplied to the combustion gas. At this time, the thermal spray material is conveyed from a thermal spray material supply device (not shown) to the thermal spray material supply unit 104 by a carrier gas such as nitrogen gas and supplied by being blown into the combustion gas together with the carrier gas.

  The spray material supply position by the spray material supply unit 104 will be described. The tip portion 104a, which is the position for supplying the thermal spray material to the combustion gas by the thermal spray material supply unit 104, melts the thermal spray material supplied from the thermal spray material supply unit 104 to the combustion gas inside the thermal spray apparatus 100 by the combustion gas. The spraying material is set at a position where the spraying material can be supplied so that the spraying material is discharged to the outside from the spray port 103a of the spraying device 100 before the spraying device 100 is discharged.

  When the thermal spray material supply unit 4 is disposed between the thermal spray nozzle 5 and the Laval nozzle 3 as in the conventional thermal spray apparatus shown in FIG. 1, while the thermal spray material passes through the thermal spray nozzle 5. The particles of the thermal spray material were melted and easily adhered to the inner surface of the thermal spray nozzle 5 cooled with water.

  On the other hand, in the thermal spraying apparatus 100 of the present embodiment, as described above, the tip portion 104a, which is the supply position of the thermal spray material, is sprayed from the injection port 103a before being melted after the thermal spray material is supplied to the combustion gas. It is set at a position on the downstream side of the combustion gas flow as compared with the prior art such that it is injected to the outside of the apparatus 100. For this reason, the particles of the thermal spray material are discharged to the outside of the thermal spraying apparatus 100 before the particles of the thermal spray material are likely to adhere inside the thermal spray nozzle 103, thereby making it difficult for the thermal spray material to adhere to the inner surface of the thermal spray nozzle 103. Can do. By making adhesion less likely to occur, spitting can be effectively prevented.

As a spraying material supply position by the spraying material supply unit 104 that satisfies the above conditions, assuming that the melting temperature of the spraying material is T1, and the temperature at the spray port 103a of the particles of the spraying material is T2,
T1> T2 (1)
It is preferable to set the supply position (tip portion 104a) of the thermal spray material supply unit 104 at a position where the thermal spray material can be supplied while satisfying the above conditions. If the tip 104a is arranged at such a position, the sprayed material is discharged from the spraying device 100 before it is in a molten state where it can easily adhere, and adhesion of the sprayed material to the inside of the device and spitting can be prevented.

  Moreover, in this embodiment, the front-end | tip part 104a which is a spraying material supply position by the spraying material supply part 104 is arrange | positioned in the position where the space | interval with the injection nozzle 103a located in the front-end | tip of the thermal spraying apparatus 100 is 30 mm or less. . At this position, the above conditions can be satisfied, and even if the spray material is supplied from the spray material supply unit 104 to the combustion gas, the spray material is injected outside the apparatus without adhering to the inner surface of the spray nozzle 103 or the like. , Can prevent spitting. In the case where it is disposed upstream of the combustion gas flow from 30 mm, adhesion of the thermal spray material into the thermal spray nozzle 103 and spitting occur. The occurrence of adhesion and spitting in the thermal spray nozzle 103 was visually confirmed.

  In addition, when the spray material supply position of the spray material supply unit 104 is set to a position in the range, the distance that the spray material passes through the inside of the spray nozzle 103 is very short compared to the conventional case, so that the spray material collides with the inner surface of the spray nozzle. Thus, it is possible to prevent wear. In the case of the conventional thermal spraying apparatus as shown in FIG. 1, since the thermal spray material passes from the end of the thermal spray nozzle 5 on the combustion chamber 2 side to the end, the inner surface of the thermal spray nozzle 5 is worn and the lifetime of the thermal spray nozzle is reached. Was very short. However, if the spray material supply position (104a) is arranged in the vicinity of the injection port 103a as in the present embodiment, the distance passing through the spray nozzle 103 is shortened, thus preventing wear on the inner surface of the spray nozzle 103. be able to.

  In the thermal spraying apparatus 100 shown in FIG. 6, the thermal spray material supply units 104 are provided at two locations on the top and bottom of the thermal spray nozzle 103, but may be provided at one location or a plurality of locations.

As the thermal spray material supplied from the thermal spray material supply unit 104, a mixture of an alloy such as a Ni base, a Ni—Cr base, and a Co base and a material having a function in accordance with required resistance can be used. Moreover, the average particle diameter of the thermal spray material can use D50 _% 40 micrometers-0.5 micrometer also called the median diameter computed by the laser diffraction scattering type | mold measuring method. In a normal high-speed gas spraying apparatus, if a sprayed material of particles having an average particle diameter of less than 10 μm, generally called fine powder, is used, the temperature of the particles rises too much and melts easily. It was easy to cause clogging of spitting and thermal spray nozzles. However, according to the high-speed gas spraying apparatus 100 of the present embodiment, it is difficult to use the conventional high-speed gas spraying apparatus because it is difficult to adhere to the inside of the spraying nozzle 103 and spitting can be effectively prevented. Even a fine powder sprayed material containing particles having an average particle diameter of 10 μm or less can be stably sprayed.

  Further, the thermal spray material supply unit 104 of the present embodiment is arranged so that the tip end portion 104 a does not protrude from the inner surface of the thermal spray nozzle 103 and does not protrude into the combustion gas flowing through the thermal spray nozzle 103. When the tip of the thermal spray material supply unit 104 protrudes into the combustion gas, the flow of the combustion gas may be disturbed, and the supplied thermal spray material may be blown off by the combustion gas. Therefore, it is preferable to arrange the tip portion 104 a of the thermal spray material supply unit 104 so as not to protrude from the inner surface of the thermal spray nozzle 103 as in this embodiment. Furthermore, since the tip 104a of the thermal spray material supply unit 104 does not protrude into the high-temperature combustion gas, the thermal spray material supply unit 104 can be prevented from being melted.

  As another configuration, a cooling pipe 108 for circulating cooling water for cooling the thermal spraying apparatus 100 is disposed around the combustion chamber 101 and the thermal spray nozzle 103. The cooling water is introduced from the cooling pipe supply hole 108a and discharged from the cooling pipe discharge port 108b. Since the thermal spraying apparatus 100 becomes very high at the time of thermal spraying, it is preferable to have such a cooling structure.

  Next, operation | movement of the thermal spraying apparatus 100 of this embodiment is demonstrated.

  As described above, the high-speed gas spraying apparatus 100 according to the present embodiment performs high-speed combustion obtained by igniting the fuel and oxygen supplied at high speed from the fuel supply unit 106 and the oxygen gas supply unit 107 disposed at the rear end thereof. By injecting gas from the thermal spray nozzle 103 and supplying the thermal spray material to the combustion gas, the thermal spray material collides with the thermal spray material at a high speed.

First, fuel (kerosene) is supplied at a flow rate of 15.5 liters / h to 26.5 liters / h from a fuel supply unit 106 and an oxygen gas supply unit 107 at the rear of the combustion chamber 101. oxygen is supplied at a flow rate of ^{48m 3} / ^h~53m 3 / h approximately. In this state, the fuel is ignited and burned, and the combustion gas is injected from the combustion chamber 101 toward the injection port 103a at the tip of the spray nozzle 103 at a high speed. At this time, the combustion gas passes through the Laval nozzle 102 and is accelerated at a higher speed than the speed supplied from the fuel supply unit 106 and the oxygen gas supply unit 107 to reach supersonic speed. The accelerated combustion gas is rectified when passing through the thermal spray nozzle 103, and the convergence is improved.

  Then, a thermal spray material is supplied to the combustion gas from a thermal spray material supply unit 104 disposed on the tip side of the thermal spray nozzle 103. As described above, the supply position (104a) of the thermal spray material from the thermal spray material supply unit 104 is set to a position where the thermal spray material is supplied to the combustion gas and discharged from the injection port 103a before the particles of the thermal spray material are melted. Is done. Therefore, the thermal spray material supplied to the combustion gas is injected outside the thermal spraying apparatus 100 before being melted, and does not adhere to the thermal spray nozzle 103 or the like. The thermal spray material sprayed without adhering to the inside of the thermal spray apparatus 100 reaches a temperature suitable for thermal spraying of each thermal spray material until it reaches the thermal spray material, and collides with the thermal spray material to form the thermal spray coating. It is formed. Here, in the case of a thermal spray material having a particle size of about 10 μm to 30 μm as in the prior art, the temperature is less likely to rise compared to a fine powder thermal spray material. Therefore, if the distance from the introduction to the combustion gas until it collides with the sprayed material is too short, the material reaches the sprayed material before it rises to a temperature suitable for spraying. If it does so, the fall of the quality of a sprayed coating will be caused. However, when a thermal spray material having a small particle size (average particle size of 10 μm or less) is used as in the thermal spraying apparatus of this embodiment, the temperature is likely to rise, as can be seen from the graph shown in FIG. Therefore, even if the tip of the thermal spray nozzle 103 is introduced into the combustion gas, the thermal spray reaches a temperature suitable for thermal spraying and is sprayed.

  Further, since the thermal spray material supply unit 104 of this embodiment directly supplies the thermal spray material to the combustion gas flowing at supersonic speed, the thermal spray material is quickly drawn into the combustion gas by the negative pressure due to dynamic pressure. To go. Therefore, the thermal spray material is not blown away by the combustion gas and the thermal sprayer is not damaged. In addition, the yield can be improved.

(Example 2)
FIG. 7 is a cross-sectional view of the high-speed gas spraying apparatus 200 of Example 2 of the present embodiment. The second embodiment is different from the thermal spraying apparatus 100 of the first embodiment in that the thermal spray material supply unit 204 is inclined. Since the other configuration is the same as that of the high-speed gas spraying apparatus 100 of the first embodiment, the duplicate description is omitted. Moreover, the same number is attached | subjected to the same member as the thermal spraying apparatus 100 of Example 1. FIG.

  Although the thermal spray material supply part 104 of Example 1 shown in FIG. 6 is formed so as to supply the thermal spray material in a direction orthogonal to the thermal spray direction, the thermal spray material supply part 204 of the present example is in the thermal spray direction. Inclination is formed on the thermal spray nozzle 103 side with respect to the direction orthogonal to the nozzle. That is, the thermal spray material supply unit 104 is disposed so as to be inclined so that the thermal spray material is supplied in a direction inclined to the downstream side in the thermal spraying direction with respect to the direction orthogonal to the thermal spraying direction. As a result, the thermal spray material is supplied in the direction in which the combustion gas travels, as compared with the case where the thermal spray material supply unit 204 is arranged perpendicular to the thermal spray direction. It can be easily pulled in.

  The inclination angle of the thermal spray material supply unit 204 may be arranged such that the extension line in the spraying material supply direction is outside the thermal spray apparatus 200 with respect to the spray port 103a. By disposing the thermal spray material supply unit 204 in this way, even if the thermal spray material advances through the combustion gas, the extension line in the thermal spray material supply direction is outside the thermal spraying apparatus 200, so that the thermal spray material is It is possible to prevent the inside of the thermal spraying apparatus such as the inner surface of the thermal spray nozzle 203 from colliding or adhering.

  In the thermal spray material supply unit 204 of the present embodiment, the thermal spray material supplied from the tip end portion 204a of the thermal spray material supply unit 204 to the combustion gas in the thermal spraying apparatus 200 is generated by the combustion gas, as in the case of the first embodiment. It arrange | positions in the position which can supply a thermal spray material so that it may discharge | emit outside from the injection nozzle 103a of the thermal spray apparatus 200, before it fuse | melts.

Furthermore, when the melting temperature of the thermal spray material is T1, and the temperature at the spray port 103a of the particles of the thermal spray material is T2,
T1> T2 (1)
It is preferable to arrange the tip end portion 204a of the thermal spray material supply unit 204 at a position where the thermal spray material can be supplied while satisfying the above conditions.

  In the present embodiment, as in the first embodiment, the tip end portion 204a of the thermal spray material supply unit 204 is disposed at a position within 30 mm from the injection port 103a located at the tip end of the thermal spray apparatus 200. .

  The thermal spray material supply unit 204 may be formed in any way as long as the thermal spray material is supplied in the direction inclined toward the thermal spray direction as described above. That is, the tip portion 204a (supply position) of the thermal spray material supply unit 204 is disposed on the front side in the thermal spray direction with respect to the upstream portion in the thermal spray material supply direction, thereby forming an inclined portion and passing through the inclined portion. By doing so, it is sufficient that the thermal spray material can be supplied obliquely to the combustion gas. In the thermal spraying apparatus 200 of the present embodiment shown in FIG. 6, the entire thermal spray material supply unit 204 is disposed to be inclined. However, for example, only the tip side of the thermal spray material supply unit 204 may be inclined. In other words, any shape that allows the spray material to be supplied so that the supply direction of the spray material has a component in the flow direction of the combustion gas may be used.

(Example 3)
FIG. 8 is a cross-sectional view of the high-speed gas spraying apparatus 300 according to the third embodiment. The thermal spraying apparatus 300 of the third embodiment supplies a cylindrical gas 311 of a cylindrical airflow so as to surround a combustion gas containing a thermal spray material injected from the injection port 103a from the tip of the thermal spraying apparatus. The point which has the gas supply part 310 differs from the previous Example. By supplying an inert gas from the cylindrical gas supply unit 310 to form a cylindrical gas 311 surrounding the combustion gas, the inside of the air flow of the cylindrical gas 311 is made an inert gas atmosphere, and the combustion gas It is possible to prevent the flow of oxygen from entraining oxygen in the atmosphere and to suppress oxidation of the thermal spray material. The conditions of the arrangement position of the tip end portion 104a of the thermal spray material supply unit 104 and other configurations are the same as those of the thermal spray apparatus 100 of the first embodiment.

  Hereinafter, the thermal spraying apparatus 300 will be specifically described. In addition, description is abbreviate | omitted about the same point as the structure already demonstrated.

  The cylindrical gas supply part 310 injects the inert gas supplied from the gas supply apparatus not shown from the slit-shaped cylindrical gas supply hole 310a formed so that the injection port 103a might be surrounded. Since the cylindrical gas supply hole 310a is formed so as to surround the injection port 103a, when the inert gas is injected from the cylindrical gas supply hole 310a, the combustion gas injected from the injection port 103a is not surrounded. An active gas cylindrical (tunnel-shaped) air flow (cylindrical gas 311) can be formed.

  Thus, by performing thermal spraying while surrounding the combustion gas containing the thermal spray material with the cylindrical gas 311, it is possible to prevent the surface of the thermal spray material in the combustion gas from being oxidized. When the cylindrical gas 311 is not present, the combustion gas is in contact with the air until the sprayed material collides with the sprayed material after the combustion gas containing the sprayed material is injected from the injection port 103a. It flows at high speed. For this reason, the combustion gas entrains the surrounding air, and the surface of the particles of the thermal spray material is oxidized by oxygen in the air. Particles having an oxide film have a low bonding force between the particles and a low adhesion force to the sprayed material.

  However, if the thermal spraying apparatus 300 of the present embodiment is used to spray the combustion gas while being surrounded by the inert gas cylindrical gas 311, the combustion gas flows in the inert gas atmosphere, and the combustion gas is involved. Air can be reduced. As a result, the oxygen partial pressure in the combustion gas is lowered, and the sprayed material in the combustion gas can be prevented from being oxidized.

  The cylindrical gas supply hole 310a may have any shape that can surround the combustion gas. However, the injection port 103a is usually circular, and the combustion gas is also injected in a cylindrical shape, so that it is circular. Is preferred.

  Moreover, nitrogen gas, argon gas, helium gas etc. are mentioned as an inert gas of the cylindrical gas 311 supplied from the cylindrical gas supply part 310. FIG. In addition, air may be supplied to form a cylindrical gas, and even in the case of air, it is possible to prevent oxidation of the thermal spray material to some extent by reducing the pressure in the cylindrical gas.

  The flow rate of the cylindrical gas 311 is preferably 1 liter / sec or more.

  Further, in order to improve the convergence of the cylindrical gas 311 injected from the cylindrical gas supply hole 310a, the outer peripheral surface of the cylindrical gas supply hole 310a may be extended forward in the injection direction. FIG. 9 shows a thermal spraying apparatus 300 having an extension 310e in which an outer portion of the cylindrical gas supply hole 310a extends forward in the injection direction.

  Thus, the cylindrical gas 311 flows along the part of the extended outer peripheral surface by extending the outer peripheral surface of the cylindrical gas supply hole 310a ahead of the inner peripheral surface in the injection direction. As a result, the cylindrical gas 311 can be prevented from bulging outward as compared with the case where the extension portion 310e is not provided, so that the cylindrical gas 311 closer to the cylinder can be formed. And the effect which prevents the oxidation of a thermal spray material can be improved by suppressing the breadth of the cylindrical gas 311. FIG. Further, the effect of rectifying the combustion gas can be obtained, and the quality of the sprayed coating can be improved as a whole.

  In addition, although the length which the extension part 310e extends can be set suitably, it is preferable that it is 10 mm or more. Further, the extension 310e shown in FIG. 9 has a shape in which the entire tip portion of the thermal spraying apparatus 300 including the outer peripheral surface of the cylindrical gas supply hole 310a is extended forward in the injection direction, but is not limited thereto. You may make it attach a cylindrical extension part so that only an outer peripheral surface may be extended.

  8 and 9 shown in the third embodiment, the spray material supply unit 104 is formed in a direction orthogonal to the spray direction as in the first embodiment. As shown in Example 2, it is also possible to arrange the sprayed material supply section in an inclined manner. If the thermal spray material supply unit is disposed at an inclination and the thermal spray material is supplied in the thermal spraying direction, the turbulence in the flow of the combustion gas can be reduced.

Example 4
FIG. 10 is a sectional view of the high-speed gas spraying apparatus 400 of the fourth embodiment. The thermal spraying apparatus 400 according to the present embodiment is different from the above-described embodiment in that the thermal spraying apparatus 400 includes an injection unit 420b as an injection port member through which combustion gas is injected at the tip of the thermal spray nozzle 103. The thermal spray material supply unit 404 is disposed in the injection unit 420b, and the thermal spraying device main body 420a excluding the injection unit 420b has the same configuration as that of the conventional high-speed gas spraying device. The tip portion 404a, which is the spray material supply position of the spray material supply unit 404, is disposed at a position that satisfies the same conditions as those in the above-described embodiment from the injection port 403a through which the combustion gas of the injection unit 420b is injected. Thereby, like the thermal spraying apparatus 100 of Example 1, adhesion and spitting of the thermal spray material to the inside of the thermal spraying apparatus can be prevented.

  Therefore, since the thermal spraying apparatus 400 of the present embodiment can be configured by attaching the injection section 420b to the conventional high-speed gas spraying apparatus, the conventional thermal spraying apparatus is used as it is and is a fine powder spraying material having a small particle size. Even in this case, the thermal spraying apparatus 400 is obtained in which spitting hardly occurs.

  Hereinafter, the structure of the thermal spraying apparatus 400 of a present Example is demonstrated concretely. Note that the description of overlapping parts is omitted.

  As described above, the thermal spraying apparatus 400 according to the present embodiment includes the thermal spraying apparatus main body 420a and the spraying part 420b serving as a spraying port member attached to the tip of the spraying nozzle 103 in the spraying direction. The thermal spraying device main body 420a has the same configuration as the conventional thermal spraying device as shown in FIG. 1, and unlike the thermal spraying devices of the first to third embodiments, the thermal spray material supply unit is disposed at the tip of the thermal spraying nozzle 103 in the thermal spraying direction. It has not been.

  The thermal spray nozzle 103 of the thermal spraying device main body 420a is connected to an injection unit 420b having an injection port 403a having an inner diameter equal to or larger than the inner diameter of the thermal spray nozzle 103. The injection port 403a has a constant diameter from the connection portion with the spray nozzle 103 to the opening 403b at the tip in the spray direction. The inner diameter is the same as or larger than the inner diameter of the thermal spray nozzle 103. If the inner diameter is smaller than the inner diameter of the thermal spray nozzle 103, a step is formed at the connecting portion between the thermal spray nozzle 103 and the injection port 403 a, which is not preferable.

  The thermal spray material supply unit 404 of the thermal spraying apparatus 400 is disposed on the opening 403b side at the tip of the spray port 403a in the spraying direction. The thermal spray material supply unit 404 is opened so that the tip end 404a does not protrude from the inner surface of the injection port 403a. The thermal spray material supply unit 404 is connected to a thermal spray material supply device (not shown), and the thermal spray material is supplied from the device to the thermal spray material supply unit 404 by a carrier gas.

  The tip portion 404a (spray material supply position) of the spray material supply unit 404 is an injection port of the spray device 400 before the spray material supplied from the spray material supply unit 404 to the combustion gas is melted by the combustion gas. It arrange | positions in the position which can supply a thermal spray material so that it may be discharged | emitted from the opening part 403b of 403a. That is, before the thermal spray material supplied from the thermal spray material supply unit 404 is heated by the combustion gas inside the injection port 403a and reaches the melting temperature of the thermal spray material and melts, it is injected out of the thermal spraying device 400 from the opening 403b. The tip portion 404a of the thermal spray material supply unit 404 is disposed at such a position.

  By disposing the tip portion 404a of the thermal spray material supply unit 404 at such a position, the thermal spray material is discharged to the outside of the thermal spraying device 400 before the thermal spraying particles are melted and are likely to adhere to the inside of the thermal spraying device. Can do. Thereby, it can reduce that a thermal spray material adheres to the inside of the thermal spray apparatus main body 420a or the injection part 420b, and can also prevent spitting.

Further, the position of the tip portion 404a of the thermal spray material supply unit 404 that satisfies the above conditions can be defined from the temperature condition of the thermal spray material as in the case of the above-described embodiment. That is, when the melting temperature of the thermal spray material is T1, and the temperature at the opening 403b of the spray port 403a of the thermal spray material is T3,
T1> T3 (2)
It is preferable to dispose the tip end portion 404a at a position where the thermal spray material can be supplied while satisfying the above conditions. By disposing the tip portion 404a at such a position, the sprayed material is discharged from the spraying device 400 before it is in a molten state where it can easily adhere, and adhesion of the sprayed material to the inside of the device and spitting can be prevented.

  In the present embodiment, the tip portion 404a, which is the spray material supply position of the spray material supply unit 404, is disposed at a position within 30 mm from the tip of the spray unit 420b. At this position, the above conditions can be satisfied, and even if the spray material is supplied from the spray material supply unit 404 into the combustion gas, the spray material does not adhere to the inner surface of the injection port 403a and the like. It is sprayed out and spitting can be prevented.

  Further, when the thermal spray material supply unit 404 is arranged at a position within the range, the thermal spray material does not pass through the thermal spray nozzle 103, so that the inner surface of the thermal spray nozzle 103 is not worn by the thermal spray material. Moreover, since the distance which passes through the inside of the injection port 403a is short, it can prevent that a thermal spray material collides with the inner surface of the injection port 403a, and wears.

  In the thermal spraying apparatus 400 shown in FIG. 10, the thermal spray material supply unit 404 is provided at two locations on the top and bottom of the injection unit 420b, but it may be provided at one location or a plurality of locations.

  Further, as shown in the second embodiment, the thermal spray material supply unit 404 can be arranged to be inclined, and if the supply direction of the thermal spray material is supplied in the thermal spray direction, the same as in the second embodiment. In addition, it is possible to reduce the disturbance of the combustion gas flow.

  In the thermal spray material supply unit 404 of the present embodiment, the tip end portion 404a is disposed without protruding from the inner surface of the injection port 403a of the injection unit 420b, and does not protrude into the combustion gas flowing through the injection port 403a. When the tip 404a of the thermal spray material supply unit 404 protrudes from the combustion gas, the flow of the combustion gas may be disturbed, and the supplied thermal spray material may be blown off by the combustion gas. Therefore, it is preferable to arrange the thermal spray material supply unit so as not to protrude from the inner surface of the injection port 403a as in this embodiment. Furthermore, since the tip portion 404a of the thermal spray material supply unit 404 does not protrude into the high-temperature combustion gas, it is possible to prevent the thermal spray material supply unit 404 from being melted.

  Moreover, the injection part 420b of the thermal spraying apparatus 400 of a present Example shown in FIG. 10 has the cylindrical gas supply part 410 which injects the cylindrical gas 411 demonstrated in Example 3. FIG. The operation and effect of the cylindrical gas supply unit 410 and the cylindrical gas supply hole 410a and the cylindrical gas 411 formed by the inert gas injected from the cylindrical gas supply hole 410a are the same as those described in the third embodiment. Is the same.

  That is, when spraying a thermal spray material having a small particle size using a conventional high-speed gas sprayer, the injection unit 420b including the cylindrical gas supply unit 410 is attached in this way to inject the cylindrical gas 411. And the oxidation of the thermal spray material in combustion gas can be suppressed by injecting the combustion gas containing a thermal spray material in cylindrical gas.

  As shown in FIG. 9, the cylindrical gas supply hole 410 a may be provided with an extension that extends the outer peripheral surface of the cylindrical gas supply hole 410 a. By doing so, as mentioned above, the convergence of the cylindrical gas 411 can be improved, and the effect of preventing the thermal spray material from being oxidized can be improved.

  In addition, when it is not necessary to inject the cylindrical gas 411, the cylindrical gas supply part 410 and the cylindrical gas supply hole 410a may be omitted.

(Example 5)
FIG. 11 is a cross-sectional view of the high-speed gas spraying apparatus 500 of the fifth embodiment. The thermal spraying apparatus 500 of the present embodiment includes a temperature adjusting gas supply unit 512 that supplies an inert gas for controlling the temperature of the combustion gas between the connection portions of the Laval nozzle 102 and the thermal spray nozzle 103.

  The high-speed gas spraying apparatus of the present embodiment can perform spraying using a fine powder spraying material having an average particle diameter of 10 μm or less while suppressing the adhesion of the spraying material to the inside of the spraying apparatus and the occurrence of spitting. When the particle size of the thermal spray material is reduced, the proportion (bulk density) of the thermal spray material in the thermal spray coating formed on the material to be sprayed is increased, and pores can be reduced, so that a dense thermal spray coating is formed. be able to. Further, as shown in FIG. 2, since the speed of the spray particles in the combustion gas is also increased, a sprayed coating having high adhesion strength with the sprayed material can be obtained.

  However, as shown in FIG. 4, when the particle size of the thermal spray material is reduced, the temperature of the particles in the combustion gas also increases. This is because, when the thermal spray material is a thermal spray material having an average particle size of 10 μm or less and a small thermal spray material, the specific surface area is increased as compared with an ordinary thermal spray material having an average particle size of 30 μm to 40 μm. This is because the amount of heating increases and the particle temperature is more likely to rise. Materials having various compositions are used as the thermal spray material, but the optimum temperature for thermal spraying differs depending on the material. Therefore, it is necessary to adjust the temperature of the combustion gas so that it can be sprayed at an optimum temperature. However, in the conventional thermal spraying apparatus, there is only a method for adjusting the temperature of the combustion gas by adjusting the amounts of fuel and oxygen. . Therefore, the adjustment range in which the temperature can be adjusted is narrow, and only a thermal spray material having an optimum temperature for spraying in the adjustment range can be sprayed.

  And when the particle size of the thermal spray material is small, the particle temperature tends to rise as described above and may exceed the optimum temperature, but depending on the conventional temperature adjustment method, the adjustment range may be as described above. It was narrow and it was difficult to perform thermal spraying by adjusting to an optimum particle temperature.

Therefore, the thermal spraying apparatus 500 of the fifth embodiment includes a temperature adjustment gas supply unit 512 that supplies an inert gas to adjust the temperature to an optimum temperature for thermal spraying even when a finely sprayed thermal spray material is used. By supplying an inert gas into the combustion gas from the temperature adjustment gas supply unit 512, the temperature of the combustion gas can be lowered. By lowering the temperature of the combustion gas, the temperature of the spray particles in the combustion gas is also lowered. The temperature of the spray particles can be controlled by changing the flow rate of supplying the inert gas. Table 1 shows the results of measuring the temperature of the spray particles at a position 200 mm downstream of the combustion gas flow from the tip of the spray nozzle when the flow rate of the nitrogen gas supplied from the temperature adjusting gas supply unit 512 is changed. Measurement conditions were such that Mo fine particles having an average particle diameter of 5 μm were used as the thermal spray material, the kerosene flow rate was 20.8 liter / h, and the oxygen flow rate was 51 m ³ / h.

  As can be seen from Table 1, the temperature of the spray particles can be adjusted by changing the flow rate of the gas blown from the temperature adjusting gas supply unit 512. As a result, it is possible to adjust the temperature of the finely sprayed material, which was impossible with the conventional thermal spraying apparatus, and even the finely sprayed material can be sprayed at a temperature suitable for spraying.

  A thermal spraying apparatus 500 of the present embodiment shown in FIG. 11 is obtained by adding a temperature adjustment gas supply unit 512 to the thermal spraying apparatus 100 of the first embodiment shown in FIG. Similarly, a temperature adjustment gas supply unit 512 can be added.

  The temperature adjusting gas supply unit 512 is preferably arranged on the front side in the thermal spraying direction from the Laval nozzle 102. This is because if the fuel is disposed closer to the combustion chamber 101 than the Laval nozzle 102, the amount of combustion in the combustion chamber 101 decreases and the speed of the combustion gas decreases.

  Moreover, when using the conventional thermal spraying apparatus as it is for the thermal spraying apparatus main body 420a of the thermal spraying apparatus 400 shown in Example 4, it is for temperature adjustment from the nozzle for spraying material supply provided in the conventional thermal spraying apparatus. By supplying the inert gas, the temperature adjustment gas supply unit 512 can be substituted.

  Thus, the temperature of the thermal spray material can be controlled by providing the thermal spraying apparatus of the present embodiment with the temperature adjusting gas supply unit 512. Furthermore, by supplying an inert gas, an effect of reducing the partial pressure of oxygen in the combustion gas and preventing the sprayed material from being oxidized can be obtained.

  According to the high-speed gas spraying apparatus shown in the embodiment according to the present invention, it is possible to prevent the sprayed material from adhering to the inside of the spraying apparatus and causing spitting. As a result of the fact that adhesion and spitting are less likely to occur inside the thermal spraying device, it becomes possible to use thermal spraying particles with a smaller particle size as the thermal spraying material, compared to the case where a thermal spraying material with a larger particle size is used. A denser sprayed coating having fewer pores can be formed.

  Furthermore, if a cylindrical gas supply hole is provided to supply a cylindrical gas that surrounds the combustion gas into which the thermal spray material has been blown, it prevents the thermal spray material from taking in ambient air and oxidizing the thermal spray material. Is possible. By preventing oxidation of the thermal spray material, it is possible to form a film having high adhesion to the thermal spray material.

  In addition, in this embodiment, although the high-speed gas spraying apparatus was demonstrated, the structure demonstrated in Examples 1-5 can be similarly applied also to a plasma spraying apparatus.

  That is, a spray material supply unit is arranged on the tip side of a spray nozzle of a normally used plasma spray apparatus, and the spray material supplied from the spray material supply unit is moved by the heat of the plasma jet. It sets to the position which can supply a thermal spray material so that it may discharge | emit from the injection nozzle of the front-end | tip of a thermal spraying apparatus before fuse | melting. In addition, the configuration of each of the above embodiments can be applied to a plasma spraying apparatus as well as a high-speed gas spraying apparatus. As a result, in the plasma spraying apparatus, as in the case of the high-speed gas spraying apparatus, adhesion of the sprayed material to the inside of the apparatus and spitting can be prevented, and the fine powder sprayed material can be sprayed stably.

Sectional drawing of the conventional high-speed gas spraying apparatus. The figure which shows the relationship between the particle velocity of the thermal spray material of a high-speed gas spraying apparatus, and a particle diameter. Schematic which shows adhesion of the thermal spray material to the thermal spray nozzle of a high-speed gas spraying apparatus. The figure which shows the relationship between the particle temperature and particle diameter of the thermal spray material of a high-speed gas spraying apparatus. Sectional drawing of the other conventional high-speed gas spraying apparatus. Sectional drawing of the high-speed gas spraying apparatus of Example 1 of this embodiment. Sectional drawing of the high-speed gas spraying apparatus of Example 2 of this embodiment. Sectional drawing of the high-speed gas spraying apparatus of Example 3 of this embodiment. Sectional drawing of the high-speed gas spraying apparatus provided with the extension part of the high-speed gas spraying apparatus shown in FIG. Sectional drawing of the high-speed gas spraying apparatus of Example 4 of this embodiment. Sectional drawing of the high-speed gas spraying apparatus of Example 5 of this embodiment.

Explanation of symbols

100,200,300,400,500 High-speed gas spraying apparatus 101 Combustion chamber 102 Laval type nozzle 103 Spray nozzle 103a Spray ports 104, 204, 404 Thermal spray material supply parts 104a, 204a, 404a Tip (spray material supply position)
106 Fuel supply part 107 Oxygen supply part 108 Cooling pipe 310 Cylindrical gas supply part 310a Cylindrical gas supply hole 311 Cylindrical gas 420a Thermal spray apparatus main body 420b Injection part 512 Temperature control gas supply part

Claims (15)

A thermal spray nozzle that injects the combustion gas in the thermal spray direction; and a thermal spray material supply unit that supplies the thermal spray material to the combustion gas flowing in the thermal spray nozzle, and sprays the thermal spray material onto the thermal spray material by the combustion gas. A thermal spraying device,
The sprayed material supply unit supplies the sprayed material so that the sprayed material supplied from the sprayed material supply unit is discharged from the spray port at the tip of the sprayed nozzle before being melted by the heat of the combustion gas. The thermal spraying apparatus characterized by having set. The supply position of the thermal spray material by the thermal spray material supply unit,
When the melting temperature of the thermal spray material is T1, and the temperature of the thermal spray material at the injection port is T2,
T1> T2
The thermal spraying device according to claim 1, wherein the thermal spraying device is set at a position that satisfies the following condition. A thermal spray nozzle that injects the combustion gas in the thermal spray direction; and a thermal spray material supply unit that supplies the thermal spray material to the combustion gas flowing in the thermal spray nozzle, and sprays the thermal spray material onto the thermal spray material by the combustion gas. A thermal spraying device,
The thermal spraying apparatus according to claim 1, wherein the thermal spray material supply position by the thermal spray material supply unit is set at a position within 30 mm from the spray port at the tip of the thermal spray nozzle.   The thermal spraying device according to any one of claims 1 to 3, wherein the thermal spray material supply unit is a supply pipe and is arranged so that a tip thereof does not protrude into the combustion gas.   The supply position of the thermal spray material supply unit for supplying the thermal spray material to the combustion gas is located on the front side in the thermal spray direction from the position upstream of the supply direction by a predetermined distance from the supply position. The thermal spraying device according to claim 1, wherein the thermal spraying device is characterized in that:   The thermal spraying device according to any one of claims 1 to 5, wherein the thermal spray material is fine particles having an average particle size of 10 µm or less.   It has a cylindrical gas supply hole that is formed in a cylindrical shape so as to surround the injection port and supplies a cylindrical air flow surrounding the combustion gas and the sprayed material injected from the thermal spraying device in the spraying direction. The thermal spraying device according to any one of claims 1 to 6.   The thermal spraying device according to claim 7, wherein an outer peripheral wall of the cylindrical gas supply hole extends forward in the spraying direction from an inner peripheral wall.   The thermal spraying apparatus according to claim 7 or 8, wherein the gas supplied from the cylindrical gas supply hole is an inert gas or air.   The thermal spraying apparatus according to claim 1, further comprising a temperature adjustment gas supply unit that adjusts a temperature of the combustion gas by blowing an inert gas into the combustion gas.   The thermal spraying device according to any one of claims 1 to 10, wherein the combustion gas is a plasma gas. A spraying device attached to the tip of the spray nozzle of a spraying device for spraying a sprayed material on a sprayed material by a combustion gas sprayed in the spraying direction from a spray nozzle,
An inner diameter equal to or greater than an inner diameter of the thermal spray nozzle, an injection port that communicates with the thermal spray nozzle and injects the combustion gas supplied from the thermal spray nozzle in the thermal spray direction, and the combustion gas that flows in the injection port A thermal spray material supply unit for supplying the thermal spray material to
The supply position of the thermal spray material by the thermal spray material supply unit is set so that the thermal spray material supplied from the thermal spray material supply unit is discharged from the injection port before being melted by the heat of the combustion gas. A jet port member characterized. A spraying device attached to the tip of the spray nozzle of a spraying device for spraying a sprayed material on a sprayed material by a combustion gas sprayed in the spraying direction from a spray nozzle,
An inner diameter equal to or greater than an inner diameter of the thermal spray nozzle, an injection port that communicates with the thermal spray nozzle and injects the combustion gas supplied from the thermal spray nozzle in the thermal spray direction, and the combustion gas that flows in the injection port A thermal spray material supply unit for supplying the thermal spray material to
The spray port member characterized in that the spray material supply position by the spray material supply unit is set at a position within 30 mm from the spray port.   The injection port member according to claim 12 or 13, wherein the combustion gas is a plasma gas.   A thermal spraying apparatus comprising the spray port member according to any one of claims 12 to 14.

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