KR101029582B1 - powder feeding and coating apparatus with low pressure spray nozzle - Google Patents

Abstract

Metal powder supply and coating device using the low pressure nozzle according to the present invention is a powder supply tank connected by a high-pressure generating means having a high-pressure gas tank, a first connection pipe provided with a tank and the first valve of the high-pressure generating means, A metal powder lead-out unit installed in the discharge pipe connected to the powder supply tank to draw metal powder from the powder supply tank by a pressure difference, a second connection pipe connected to the high pressure gas tank and provided with the metal powder lead-out unit, and the high pressure The third connecting pipe is connected to the gas tank and provided with a heating means for heating the gas to be transported, and the third connecting pipe and the second connecting pipe to which the metal powder is supplied are combined to spray metal powder at a high speed for low temperature coating. A spray nozzle is included.

Metal powder, spraying, high pressure, metal powder supply, spray nozzle

Description

Metal powder supply and coating apparatus using low pressure nozzle {powder feeding and coating apparatus with low pressure spray nozzle}

The present invention relates to a coating apparatus for forming a porous metal film for heat dissipation, and to a relatively low pressure due to metal powder supply, to a metal powder supply using a low pressure nozzle that can recycle waste heat and to a coating apparatus thereof will be.

Typically, the porous coating layer formed on the surface of the member can bring about an improvement in the thermal mechanical properties of the member. For example, when a porous coating layer composed of interconnected pores is formed on the surface of the heat exchanger, the heat exchanger may have a wider contact area with the surrounding air to achieve more efficient heat exchange performance. On the other hand, in the case of the friction member, the member may be required to have a low strength and hardness depending on the relationship with the peripheral components, and the porous coating layer may satisfy this requirement. In addition, in the bonding of the base material and the dissimilar material, stress due to lattice mismatching may occur at the bonding interface, and the porous coating layer may also act as a buffer layer to solve such bonding stress.

In particular, the heat transfer tube has a large number of micro-sized structures on the heat transfer surface, that is, a nucleus ratio, etc., that is, a pore size larger than 1 µm and smaller than 1 mm. It has a structure that dramatically increases the active site such as nuclear boiling with an appropriate heat transfer area.

These heat pipes have more than twice the heat transfer performance compared to the conventional fin-type heat pipes, and the use of raw materials such as copper, nickel, and titanium by embossing coating can be reduced by 1/2, and manufacturing costs can be reduced by 30%.

Various coating methods have been used as a method of forming the metal coating layer on the surface of the heat transfer tube. For example, electroplating, hot-dip plating or thermal spraying is an example. However, these methods are subject to application constraints, thermal shock to the substrate or

It may cause thermal deformation. In addition, it is practically difficult to artificially control the porosity or control the pore distribution in the coating layer by these methods.

Therefore, the porous coating film is formed by using a low temperature spraying method, which uses a powder supplying device capable of inserting high pressure air into a spray nozzle capable of producing a supersonic speed and supplying a predetermined amount of metal powder to be coated over the same pressure. Should be used. Since the powder supplying device has a high pressure of 8 to 40 atm, the tank and the pipe should be designed and manufactured in consideration of stability, and thus, a lot of manufacturing costs are required. In addition, in the case of the conventional metal powder supply apparatus, the supply of the metal powder tends to be non-uniform, and thus there is a problem in that the porous metal coating film cannot be formed to a uniform thickness.

Korean Patent Laid-Open Publication No. 2005-0081252 discloses a manufacturing method using a porous metal member and a low temperature spraying method. This manufacturing method has a problem in that the powder may not be uniformly supplied or the powder may be supplied using low pressure, and waste heat cannot be utilized.

In view of the above-described problems, the present invention can supply a metal powder for forming a porous metal coating film using a low pressure at a uniform speed, and a metal using a low pressure nozzle capable of forming a porous metal coating film at a uniform thickness. Its purpose is to provide a powder feed and a coating apparatus thereof.

Another object of the present invention is to provide a metal powder supplying and coating apparatus thereof using a low pressure nozzle capable of continuously supplying a predetermined amount in a state where low pressure is applied to a tank in which the metal powder is stored.

Metal powder supply and coating apparatus thereof using the low pressure nozzle of the present invention for achieving the above object is connected by a high pressure generating means having a high pressure gas tank, a tank of the high pressure generating means and a first connecting pipe provided with a first valve Powder feed tank,

A metal powder extracting part installed at an outlet pipe connected to the powder supply tank and for extracting the metal powder from the powder supply tank by a pressure difference;

A second connection pipe connected to the high pressure gas tank and provided with the metal powder outlet;

The third connecting pipe is connected to the high-pressure gas tank and provided with a heating means for heating the gas to be transported, and the third connecting pipe is connected to the second connecting pipe to which the metal powder is supplied to inject metal powder at high speed so that it can be cooled. Characterized in that it comprises a spray nozzle to be deposited.

In the present invention, the metal powder lead-out portion is provided on the second connecting pipe, the first pipe is formed in the orifice is formed in the main body, the second pipe is formed in the orifice is connected to the discharge pipe.

The powder supply tank further includes a powder supply means for continuously supplying powder to the discharge pipe.

The powder supply means is installed in the lower portion of the powder supply tank and the base member is formed in the metal powder discharge hole communicating with the discharge pipe, the withdrawal wing is installed at the end of the rotating shaft rotatably installed on the base member, And a disk having a divided supply hole communicating with the metal powder discharge hole at predetermined intervals, and a driving motor for rotating the rotating shaft.

Further, there is further provided a recovery means for recovering the metal powder dispersed after the dispersion from the injection nozzle.

The powder supply using the low pressure nozzle and the coating apparatus according to the present invention can supply the metal powder from the powder storage tank continuously and uniformly, and can lower the pressure applied to the powder storage tank. In addition, it is possible to recover the metal powder scattered without being attached to the pipe member by being injected from the injection nozzle to prevent the loss of the metal powder, it is possible to recover the waste heat.

Metal powder supply and coating device using the low pressure nozzle according to the present invention is to form a porous coating film for heat dissipation on the surface of the pipe member used in the heat exchanger or refrigeration apparatus, subsonic or supersonic the metal powder to form a coating layer Accelerated by spraying to pipe member. The coating apparatus ejects about 1 to 50 μm of metal powder provided from the powder supply tank by a compressed gas of about 5 to 20 atmospheres at a speed of about 300 to 1200 mm / s through a spray nozzle. The powder ejected with the gas impinges on the tube member, where the kinetic energy of the powder plastically deforms the metal powder during the collision of the tube member and provides a bonding force on the surface of the tube part, resulting in a very high density porous coating layer. To form.

An embodiment of a coating apparatus according to the present invention for forming such a porous coating layer is shown in FIG. 1.

Referring to the drawings, the coating apparatus 10 includes a high pressure generating means 20 having a high pressure gas tank 21, a first connecting pipe 31 provided with the high pressure gas tank 21 and the first valve 41. It is provided with a powder supply tank 50 connected by. The high pressure generating means 22 is provided with a compressor 22 for compressing gas, that is, air, in the high pressure gas tank 21.

And a metal powder extracting part 60 installed in the discharge pipe 51 connected to the powder supply tank 50 to extract the metal powder from the powder supply tank 50 due to the pressure difference, and the high pressure gas tank 21. A second connecting pipe 32 connected to or connected to the first connecting pipe 31 and provided with the metal powder extracting part, and connected to the first connecting pipe 31 or connected to a high pressure gas tank to heat the gas transferred. The third connecting pipe 33 is provided with a heating means 70 for the purpose, the third connecting pipe 33 and the second connecting pipe 32 is supplied with a metal powder is combined to spray metal powder at high speed to low temperature A spray nozzle 80 for depositing is provided.

The first, second, and third flow pipes 31, 32, and 33 are first, second, and third flowmeters 44-46, and the first, second, and third valves 41, 42, 43, respectively. Is installed. The first, second and third valves are preferably used to control the pressure.

The rapid powder withdrawal unit 60 is installed on the second connecting pipe 32, the first pipe passage 63 is formed with an orifice 62 is formed in the main body 61, the orifice 62 A second conduit 64 is formed in the forming portion and connected to the discharge pipe 51. The metal powder withdrawal unit is preferably a negative pressure acts on the second conduit 64 by the high-pressure gas flowing through the first conduit 63 so that the metal powder in the powder supply tank 50 is sucked.

In addition, the powder supply tank 50 in which pressure acts inside by the gas supplied to the first connection pipe 31 is supplied to discharge a predetermined amount of metal powder through the discharge pipe 51 having a closed configuration. A powder supply means 90 is further provided.

The powder supply means 90 is installed in the lower portion of the powder supply tank 50 as shown in Figure 2 and the base member 92 is formed with a metal powder discharge hole 91 in communication with the discharge pipe 51, It is provided with a take-out wing 94 is installed at the end of the rotating shaft 93 rotatably installed on the base member 92. The disk 96 and the disc supply hole 95 are installed in the rotating shaft 93 and communicate with the metal powder discharge hole 91 at predetermined intervals and are in close contact with the base member 92. It includes a drive motor 97 for rotating the rotating shaft (93). A hole communicating with the metal powder discharge hole is formed in the lower portion of the base member 92, and an auxiliary cover 98 for sealing is coupled, and the divided supply hole is provided between the auxiliary cover 98 and the base member 92. An auxiliary disk 99 in which an auxiliary dividing hole 99a corresponding to 95 is formed is installed.

The heating means 70 is to heat the air supplied through the third connecting pipe 33, the chamber 71 is installed in the third connecting pipe 33, and the heater is installed in the chamber 71 And 72.

On the other hand, as shown in Figure 3 is further provided with a recovery means 100 for recovering the metal powder scattered after being injected from the injection nozzle (80). The recovery means 100 includes a housing 101 having an opening formed at a side corresponding to the injection nozzle 80 and surrounding the pipe member 200 to form a porous coating film, and a dust collector 102 connected to the housing 101. ) And an exhaust pump 103 installed in the fourth connecting pipe 34 connected to the dust collector. The dust collector 102 rotates the gas sucked by mixing with the metal powder from the housing using the principle of cyclone to generate a fire flow so that the metal powder is discharged to the lower side of the dust collector. The fourth connection pipe is further provided with a heat exchanger 110 for recovering heat from the discharged gas. The heat recovered by the heat exchanger 110 may be used to heat the gas transferred through the second discharge pipe or the third discharge pipe.

The metal powder for coating may be Al, Ti, Si, Mn, Cr, Fe, Co, Ni, Cu, etc., and binary or Al-Mg such as Al-Mg, Al-Zn, Al-Sn. Ternary or higher metals, such as -Zn, may be used.

Referring to the operation of the coating apparatus according to the present invention configured as described above are as follows.

First, the gas is compressed in the high pressure gas tank 21 by using the compressor 22, and the powder supply tank 50 is filled with a metal powder for forming a coating film on the surface of the pipe member 200. The tubular member 200 for forming the coating film is mounted on the housing 101 corresponding to the nozzle 80.

In this state, the first, second, and third valves 41, 42, 43 are lower than the pressure of the gas supplied to the first, second, and third pipes 32 and 33 through the first connection pipe 31. A relatively low pressure is supplied to the inside of the powder supply tank 50. Then, the motor of the powder supply means 90 is driven to drive the rotating shaft 93 supported by the base member 92. In this case, while the extraction blade 94 installed at the end of the rotary shaft 93 rotates, the metal powder installed inside the powder supply tank 50 is stirred, and the disk 96 rotates. In this process, the divided supply holes 95 and the discharge holes 91 formed in the disk 96 coincide with each other, and the metal powder is supplied by a predetermined amount. At this time, even if a high pressure for discharging the metal powder is not applied to the powder supply tank 50, the metal powder is smoothly discharged by the negative pressure acting on the discharge pipe 51 by the metal powder inlet / out part 60. .

The metal powder discharged as described above is supplied to the injection nozzle 80 through the second connection pipe 32 and piggybacked on high-pressure high-speed air supplied through the third connection pipe 33 connected to the injection nozzle to provide a pipe member ( 200) to form a porous coating film.

In the process of forming a porous coating film on the tubular member 200 as described above, the metal powder that is not attached to the tubular member 200 after being sprayed from the spray nozzle 80 is scattered by the exhaust pump 103 of the recovery means 100. Is sucked into the dust collector 102 by the driving of the dust collector, and is collected by the dust collector 102. Therefore, it is possible to recover the metal powder scattered without being attached to the metal member. In addition, since the heat exchanger is installed in the fourth connection pipe, waste heat may be recovered and recycled for heating such as air supplied to the second connection pipe.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the scope of the invention.

Therefore, the true scope of protection of the present invention should be defined only by the appended claims.

The present invention is widely applicable to the formation of a porous thin film of a material for releasing heat such as a tube and a plate.

1 is a view showing a powder supply and a porous metal coating apparatus using a low pressure nozzle according to the present invention,

Figure 2 is an exploded perspective view showing an extract powder supply means according to the present invention.

3 is a view showing another embodiment of a powder supply and porous metal coating apparatus using a low pressure nozzle according to the present invention,

Claims (4)

A high pressure generating means having a high pressure gas tank, a powder supply tank connected by a tank of the high pressure generating means and a first connecting pipe provided with a first valve, and a discharge powder connected to the powder supply tank, and the metal powder Is provided with a metal powder lead-out unit for withdrawing the powder from the powder supply tank, a second connecting pipe connected to the high pressure gas tank and provided with the metal powder lead-out unit, and a heating means connected to the high pressure gas tank to heat the gas to be transferred. A third connecting pipe and a second connecting pipe supplied with the third connecting pipe and the metal powder are coupled to each other to include a spray nozzle for spraying metal powder at a high speed to perform low temperature deposition; The powder supply tank further comprises a powder supply means for continuously supplying powder to the discharge pipe, the powder supply means is installed in the lower portion of the powder supply tank and the base member is formed with a metal powder discharge hole in communication with the discharge pipe, A disc having a drawing blade provided at an end of the rotating shaft rotatably installed at the base member, a split supply hole provided at the rotating shaft and communicating with the metal powder discharge hole, and a drive motor for rotating the rotating shaft. Metal powder supply and coating device thereof using a low pressure nozzle comprising a. The method of claim 1, The metal powder lead-out portion is installed on the second connecting pipe, the first pipe is formed in the orifice is formed in the main body, the low pressure nozzle, characterized in that the second pipe is connected to the discharge pipe formed in the forming portion in the orifice Metal powder supply and coating device thereof. delete The method of claim 1, Metal powder supply using the low-pressure nozzle and coating device characterized in that it further comprises a recovery means for recovering the metal powder scattered from the spray nozzle after scattering.

Images