CN114918055A - An upstream and downstream powder feeding nozzle for cold spraying and a coating cold spraying production system - Google Patents

Abstract

The invention provides an upstream and downstream powder feeding nozzle for cold spraying and a coating cold spraying production system, and relates to the technical field of cold spraying. The upstream and downstream powder feeding nozzle for cold spraying comprises a shrinking pipe section, an expanding pipe section and an extending pipe section, the shrinking pipe section is connected with the expanding pipe section, the end of the expanding pipe section far from the shrinking pipe section is connected with the extending pipe section, the shrinking pipe section is provided with an upstream powder feeding nozzle, and the extending pipe section is provided with There is at least one downstream powder nozzle. The upstream powder feeding nozzle and the downstream powder feeding nozzle can realize the simultaneous feeding of two powders, without the need to mix the powders before feeding, and the proportion and speed of the powders can be controlled. At the same time, it can also realize separate upstream powder feeding or separate downstream powder feeding, reduce the disassembly of the nozzle equipment, reduce the difficulty of operation, and can realize the preparation of gradient coatings with uniform powder ratio changes, especially suitable for composite coating of powders with large differences in properties. preparation, the structure is simple and the production cost is low.

Description

An upstream and downstream powder feeding nozzle for cold spraying and a coating cold spraying production system

technical field

The invention relates to the technical field of cold spraying, in particular to an upstream and downstream powder feeding nozzle for cold spraying and a coating cold spraying production system.

Background technique

The coating prepared by cold spraying technology has the advantages of no melting and phase transformation of materials and unlimited thickness, which has received extensive attention from many enterprises and scientific research institutions.

When cold spraying is used to prepare composite coatings (at least two powders), at least two powders are usually mixed, and then the mixed powders are fed to the Laval nozzle through a powder feeder to realize the preparation of composite coatings. This method can only produce coatings with uniform proportions, and it is difficult to prepare gradient coatings with uniform powder proportions. For some powders with different properties, some powders are suitable for process parameters with higher process temperature, and some powders are suitable for powders with lower process temperature, which makes it more difficult to use the same process for cold spraying of composite powders.

At the same time, the cold spray nozzle will wear and block when spraying cemented carbide powder and low melting point powder, which is the main form of nozzle failure. The main solution is to reduce the spraying process parameters, replace more wear-resistant nozzle materials or reduce Due to the spraying process parameters, the performance of the coating will not reach the required index, and the service life of the nozzle is short and the cost is high.

In view of this, this application is hereby made.

SUMMARY OF THE INVENTION

The objects of the present invention include, for example, to provide an upstream and downstream powder feeding nozzle for cold spraying and a coating cold spraying production system, which can precisely control the powder feeding ratio and rate, and effectively improve the problem of easy wear.

Embodiments of the present invention can be implemented as follows:

In a first aspect, the present invention provides an upstream and downstream powder feeding nozzle for cold spraying, which includes a shrinking pipe section, an expanding pipe section, and an extending pipe section, the shrinking pipe section is in communication with the expanding pipe section, and the expanding pipe section is away from the shrinking pipe section. One end is communicated with the extended pipe section, the shrinking pipe section is provided with an upstream powder feeding nozzle, and the extended pipe section is provided with at least one downstream powder feeding nozzle.

In an optional embodiment, the upstream powder feeding nozzle is arranged coaxially with the shrinking tube section.

In an optional embodiment, the downstream powder feeding nozzle is arranged at an angle of 30-90° with the side wall in the upstream direction of the extension pipe section.

In an optional embodiment, the downstream powder feeding nozzle is vertically communicated with the side wall of the extended pipe section.

In an optional embodiment, the shrinking tube section and the dilating tube section are detachably connected.

In an optional embodiment, the shrinking tube section is provided with a first convex ring, the expansion tube section is provided with a first groove, and the first convex ring is connected to the first convex ring by means of screw connection or sleeve connection. The inside of the groove thread.

In an optional embodiment, when the first convex ring and the first groove are sleeved connected, a sealing ring is further provided between the first convex ring and the first groove.

In an optional embodiment, the expansion tube section and the extension tube section are detachably connected.

In an optional embodiment, the expansion pipe segment is provided with a second convex ring, the extension pipe segment is provided with a second groove, and the second convex ring is connected to the second convex ring by means of screw connection or sleeve connection. inside the groove.

In an optional embodiment, the pipe diameter of the shrinking pipe section is gradually reduced along the direction from the shrinking pipe section to the extending pipe section, and the pipe diameter of the expanding pipe section is along the direction from the shrinking pipe section to the extending pipe section. The direction increases gradually, and the pipe diameter of the extended pipe section is uniform and equal to the maximum pipe diameter of the expanded pipe section.

In a second aspect, the present invention provides a coating cold spray production system, which includes the upstream and downstream powder feeding nozzles for cold spray according to any one of the foregoing embodiments.

The beneficial effects of the embodiments of the present invention include, for example:

The invention provides an upstream and downstream powder feeding nozzle for cold spraying, which is respectively provided with an upstream powder feeding nozzle in the constricted pipe section, and at least one downstream powder feeding nozzle is provided in the extended pipe section. The upstream powder feeding nozzle and the downstream powder feeding nozzle can realize the simultaneous feeding of two kinds of powders, without the need to mix the powders before feeding, and the proportion and speed of the powders can be controlled. At the same time, it can also realize separate upstream powder feeding or separate downstream powder feeding, which reduces the disassembly of the nozzle equipment and reduces the difficulty of operation. And in the powder feeding process, the upstream and downstream powder feeding quality can be adjusted, and then a gradient coating with uniform powder ratio can be prepared. For some powders with different properties, for example, some powders are suitable for process parameters with higher process temperature, and some powders are suitable for powders with lower process temperature, the upstream and downstream powder feeding nozzles for cold spraying provided in this application can pass The upstream and downstream powder feeding is suitable for the preparation of composite coatings for powders with large differences in the above properties. The upstream and downstream powder feeding nozzles for cold spraying provided by the present application are simple in structure and low in manufacturing cost. The coating cold spraying production system having the above-mentioned upstream and downstream powder feeding nozzles for cold spraying can realize the preparation of a variety of powder dipping coatings with large differences in quality.

Description of drawings

In order to illustrate the technical solutions of the embodiments of the present invention more clearly, the following briefly introduces the accompanying drawings used in the embodiments. It should be understood that the following drawings only show some embodiments of the present invention, and therefore do not It should be regarded as a limitation of the scope, and for those of ordinary skill in the art, other related drawings can also be obtained according to these drawings without any creative effort.

1 is a schematic structural diagram of an upstream and downstream powder feeding nozzle for cold spraying provided by the application;

FIG. 2 is a schematic view of the disassembly of the upstream and downstream powder feeding nozzles for cold spraying provided by the application.

Icon: 100-upstream and downstream powder feeding nozzles for cold spraying; 110-shrinking pipe section; 111-upstream powder feeding nozzle; 112-first convex ring; 120-expansion pipe section; 121-first groove; 122-second convex ring ; 130-extended pipe section; 131-downstream powder feeding nozzle; 132-second groove.

Detailed ways

In order to make the purposes, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments These are some embodiments of the present invention, but not all embodiments. The components of the embodiments of the invention generally described and illustrated in the drawings herein may be arranged and designed in a variety of different configurations.

Thus, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the invention as claimed, but is merely representative of selected embodiments of the invention. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

It should be noted that like numerals and letters refer to like items in the following figures, so once an item is defined in one figure, it does not require further definition and explanation in subsequent figures.

In the description of the present invention, it should be noted that, if the terms "upper", "lower", "inner", "outer", etc. appear, the orientation or positional relationship indicated is based on the orientation or positional relationship shown in the drawings, or It is the orientation or positional relationship that the product of the invention is usually placed in use, only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation , so it should not be construed as a limitation of the present invention.

In addition, where the terms "first", "second" and the like appear, they are only used to differentiate the description, and should not be construed as indicating or implying relative importance.

It should be noted that the features in the embodiments of the present invention may be combined with each other without conflict.

Referring to FIG. 1 , the present embodiment provides an upstream and downstream powder feeding nozzle 100 for cold spraying, which includes a shrinking tube section 110 , an expanding tube section 120 and an extending tube section 130 . The shrinking tube section 110 communicates with the expanding tube section 120 , and the expanding tube section 120 is far away from the shrinking tube section. One end of the pipe section 110 communicates with the extension pipe section 130 .

The diameter of the shrinking tube section 110 gradually decreases along the direction from the shrinking tube section 110 to the extending tube section 130 . In the present application, by arranging the upstream powder feeding nozzle 111 and the shrinking tube section 110 coaxially, the powder sent by the upstream powder feeding nozzle 111 can flow directly with the gas.

The diameter of the expanding tube section 120 gradually increases along the direction from the contracting tube section 110 to the extending tube section 130 .

The pipe diameter of the extension pipe section 130 is uniform and equal to the maximum pipe diameter of the expansion pipe section 120 . The extension pipe section 130 is provided with at least one downstream powder feeding nozzle 131 . The downstream powder feeding nozzle 131 is arranged at an angle of 30-90° with the side wall in the upstream direction of the extension pipe section 130 . In the present application, the downstream powder feeding nozzle 131 and the extension pipe section 130 are arranged at an angle, so that the powder sent from the downstream powder feeding nozzle 131 to the extension pipe can have a certain impact with the powder or gas from the shrinking pipe, which is convenient for downstream feeding. The powder fed by the powder nozzle 131 is evenly distributed. Preferably, in the present application, the downstream powder feeding nozzle 131 is vertically communicated with the side wall of the extension pipe section 130 . In the present application, the number of downstream powder feeding nozzles 131 can be determined according to the powder feeding quantity. When spraying two kinds of powders, the downstream powder feeding nozzle 131 is set to one, and when spraying multiple powders, the downstream powder feeding nozzle 131 can be 131 is set to multiple, and the specific quantity is the spray powder minus 1.

The structural arrangement of the shrinking tube section 110 and the expanding tube section 120 can generate supersonic flow of gas with a certain pressure and a relatively low velocity. The upstream powder feeding nozzle 111 sends the powder into the shrinking pipe. At this time, the powder spreads rapidly under the impact of the air flow, and is driven by the gas to move from the upstream to the downstream and is discharged from the discharge port. Similarly, the downstream powder feeding The nozzle 131 sends the powder into the extension pipe, and the powder in the extension pipe drives the powder from the downstream to the discharge port under the movement of the air flow. The feed powder can be thoroughly mixed in the extended pipeline.

Further, referring to FIG. 2 , in the present application, the shrinking tube section 110 , the expanding tube section 120 and the extending tube section 130 may be integrally formed, or may be a segmented structure. Preferably, the shrinkable tube section 110 , the expansion tube section 120 and the extension tube section 130 in the present application are all segmented structures, and the shrinkage tube section 110 and the expansion tube section 120 are detachably connected, and the expansion tube section 120 and the extension tube section 130 are detachably connected.

A detachable segmented structure is formed between the shrinking pipe section 110, the expanding pipe section 120 and the extending pipe section 130, which is easy to process. At the same time, since the nozzle is prone to blockage or wear during use, the segmented structure can be quickly realized. The worn and blocked parts are replaced, while the remaining unworn or blocked parts can continue to be used, which effectively reduces the production cost, and at the same time, the segmented structure also reduces the processing difficulty.

To realize the detachable connection between the shrinkable tube section 110 and the expansion tube section 120, there are many ways to detachably connect the expansion tube section 120 and the extension tube section 130, including but not limited to screw connection, clamp connection, sleeve connection and so on. Specifically in this embodiment, this embodiment shows a typical but non-limiting example, by providing a first convex ring 112 at one end of the shrinking tube section 110 , a first groove 121 at one end of the expanding tube section 120 , and a first groove 121 at the other end The second convex ring 122, the extension pipe section 130 is provided with a second groove 132, and the first convex ring 112 and the second convex ring 122 are respectively provided with external threads, and the first groove 121 and the second groove 132 are respectively provided Internal thread, the first convex ring 112 is threadedly connected to the inside of the thread of the first groove 121 , and the second convex ring 122 is threadedly connected to the inside of the second groove 132 . In this embodiment, the detachable connection between the shrinking pipe section 110, the expanding pipe section 120 and the extending pipe section 130 can be realized by the structure of the groove and the convex ring, and the thread processing is easy to implement, and the threaded connection is easy to operate during installation and disassembly. Easy to implement. It should be understood that the “sleeve connection” in this application means that the first convex ring 112 can also be directly sleeved on the inner side of the first groove 121 , and a seal is provided between the first convex ring 112 and the first groove 121 The first convex ring 112 and the first groove 121 are connected by the sleeve to realize the sleeve connection. At this time, there is no need to provide threads on the first convex ring 112 and the first groove 121 . The second convex ring 122 and the second groove 132 can also be connected by means of sleeve connection.

At present, cold spraying is mainly divided into high pressure and low pressure cold spraying. The powder of high pressure cold spraying is mainly fed through the upstream of the upstream and downstream powder feeding nozzles 100 for cold spraying. It has the characteristics of high pressure and high temperature, and is suitable for high hardness powder materials; The powder of low pressure cold spraying mainly enters into the upstream and downstream powder feeding nozzle 100 for cold spraying from the extended section of the upstream and downstream powder feeding nozzle 100 for cold spraying, that is, downstream powder feeding, which is suitable for powder materials such as low melting point.

The working principle of the upstream and downstream powder feeding nozzles 100 for cold spraying provided in this embodiment is as follows: according to the characteristics of the powder (high hardness powder materials or powder materials such as low melting points), the upstream powder feeding nozzle 111 and the downstream powder feeding nozzle 131 are selected respectively. At least one of them is used for powder feeding.

Embodiment 1:

When the copper coating is sprayed with the upstream and downstream powder feeding nozzles 100 for cold spraying provided in the present application, the upstream powder feeding nozzles are used. At this time, the extension section is directly removed, so that it directly becomes the upstream powder feeding nozzle. The spraying process parameters were set to 5MPa and 800°C.

Implementation 2:

When the babbitt alloy powder is sprayed with the upstream and downstream powder feeding nozzle 100 for cold spraying provided by the present application, the upstream powder feeding nozzle 111 is blocked, and then becomes the downstream powder feeding nozzle. At this time, the powder enters from the downstream powder feeding nozzle 131, The spraying process parameters were 0.5 MPa, and the temperature was set at 350 °C.

Embodiment 3:

When the Al/Al ₂ O ₃ composite powder is sprayed by using the upstream and downstream powder feeding nozzles 100 for cold spraying provided by the present application, the number of downstream powder feeding nozzles 131 is set to one, at this time, the Al powder is fed through the upstream and the Al ₂ O ₃ powder is passed through Downstream powder feeding, spraying process parameters are set: spraying temperature is 350 ℃, the powder feeding pressure of Al powder is 2MPa, the powder feeding pressure of Al ₂ O ₃ powder is 1 MPa, and the mass ratio of Al powder and Al ₂ O ₃ powder is 50:50.

It can be seen from the above-mentioned Embodiments 1-3 that the upstream and downstream powder feeding nozzles 100 for cold spraying provided by the present application can realize the operation of independent upstream powder feeding, independent downstream powder feeding, or simultaneous upstream and downstream powder feeding, and in the powder feeding process The upstream and downstream powder feeding quality can be adjusted, thereby enabling the preparation of gradient coatings with uniformly varying powder ratios. For some powders with widely different properties, for example, some powders are suitable for process parameters with higher process temperature, and some powders are suitable for powders with lower process temperature, the upstream and downstream powder feeding nozzle 100 for cold spraying provided in this application can be The composite coating is prepared by simultaneously feeding powder upstream and downstream to be suitable for powders with large differences in the above properties.

In addition, the present application also provides a coating cold spray production system, which includes the above-mentioned upstream and downstream powder feeding nozzles 100 for cold spray.

To sum up, the present invention provides an upstream and downstream powder feeding nozzle 100 for cold spraying, respectively provided with upstream powder feeding nozzles 111 in the constricted pipe section 110 , and at least one downstream powder feeding nozzle 131 in the extension pipe section 130 . The upstream powder feeding nozzle 111 and the downstream powder feeding nozzle 131 can realize the simultaneous powder feeding of two kinds of powders, without the need to mix the powders before powder feeding, and control the proportion and speed of the powders. At the same time, it can also realize separate upstream powder feeding or separate downstream powder feeding, which reduces the disassembly of the nozzle equipment and reduces the difficulty of operation. And in the powder feeding process, the upstream and downstream powder feeding quality can be adjusted, and then a gradient coating with uniform powder ratio can be prepared. For some powders with widely different properties, for example, some powders are suitable for process parameters with higher process temperature, and some powders are suitable for powders with lower process temperature, the upstream and downstream powder feeding nozzle 100 for cold spraying provided in this application can be The composite coating is prepared by simultaneously feeding powder upstream and downstream to be suitable for powders with large differences in the above properties. The upstream and downstream powder feeding nozzle 100 for cold spraying provided by the present application is simple in structure and low in manufacturing cost. The coating cold spraying production system having the above-mentioned upstream and downstream powder feeding nozzles 100 for cold spraying can realize the preparation of a variety of powder dip coatings with large differences in quality.

The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art who is familiar with the technical scope disclosed by the present invention can easily think of changes or substitutions. All should be included within the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims (10)

1. The upstream and downstream powder feeding nozzle for cold spraying is characterized by comprising a contraction pipe section, an expansion pipe section and an extension pipe section, wherein the contraction pipe section is communicated with the expansion pipe section, one end, far away from the contraction pipe section, of the expansion pipe section is communicated with the extension pipe section, the contraction pipe section is provided with an upstream powder feeding nozzle, and the extension pipe section is provided with at least one downstream powder feeding nozzle.

2. The upstream and downstream powder feeding nozzle for cold spray according to claim 1, wherein said upstream powder feeding nozzle is provided coaxially with said constricted tube section.

3. The upstream and downstream powder feeding nozzle for cold spray according to claim 1, wherein said downstream powder feeding nozzle is disposed at an angle of 30 to 90 ° to a side wall in an upstream direction of said elongated tube section.

4. The upstream and downstream powder feeding nozzle for cold spray according to claim 1, wherein said convergent tube section and said divergent tube section are detachably connected.

5. The upstream and downstream powder feeding nozzle for cold spray according to claim 4, wherein the convergent pipe section is provided with a first collar, and the divergent pipe section is provided with a first groove, and the first collar is connected to the inside of the first groove by means of a screw or a sleeve.

6. The upstream and downstream powder feeding nozzle for cold spray according to claim 5, wherein a seal ring is further provided between said first male ring and said first female groove when said first male ring and said first female groove are connected to each other.

7. The upstream and downstream powder feeding nozzle for cold spray according to claim 1, wherein the extension pipe section is detachably connected to the extension pipe section.

8. The upstream and downstream powder feeding nozzle for cold spray according to claim 7, wherein the extension pipe section is provided with a second collar, and the extension pipe section is provided with a second groove, and the second collar is connected to the inside of the second groove by means of a screw or a sleeve.

9. The upstream and downstream powder feeding nozzle for cold spraying according to any one of claims 1 to 8, wherein the pipe diameter of the constricted pipe section is gradually reduced in a direction from the constricted pipe section to the extended pipe section, the pipe diameter of the expanded pipe section is gradually increased in a direction from the constricted pipe section to the extended pipe section, and the pipe diameter of the extended pipe section is uniform and equal to the maximum pipe diameter of the expanded pipe section.

10. A coating cold spray production system comprising the upstream and downstream powder feeding nozzles for cold spray according to any one of claims 1 to 8.

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