CN112275519A

CN112275519A - Vacuum hole sealing equipment and hole sealing method suitable for thermal spraying coating

Info

Publication number: CN112275519A
Application number: CN202011391261.2A
Authority: CN
Inventors: 邓春银; 覃恩伟; 刘成威; 陆海峰; 史一岭; 黄骞; 王博; 吴树辉; 魏少翀; 陈国星
Original assignee: China General Nuclear Power Corp; CGN Power Co Ltd; Suzhou Nuclear Power Research Institute Co Ltd
Current assignee: China General Nuclear Power Corp; CGN Power Co Ltd; Suzhou Nuclear Power Research Institute Co Ltd
Priority date: 2020-12-02
Filing date: 2020-12-02
Publication date: 2021-01-29
Anticipated expiration: 2040-12-02
Also published as: CN112275519B

Abstract

The invention discloses vacuum hole sealing equipment suitable for a thermal spraying coating, which is used for sealing a thermal spraying coating of a coating component. According to the vacuum hole sealing equipment suitable for the thermal spraying coating, when hole sealing is carried out, the penetration depth of a hole sealing agent is deep; hot water circulation cleaning and curing are adopted, so that the coating hole sealing efficiency is improved; can realize automatic hole sealing assembly line in batches, improve hot spraying production efficiency.

Description

Vacuum hole sealing equipment and hole sealing method suitable for thermal spraying coating

Technical Field

The invention belongs to the technical field of hole sealing, and particularly relates to vacuum hole sealing equipment suitable for thermal spraying coatings and a method for sealing holes of coating components by adopting the hole sealing equipment.

Background

The thermal spraying technology is a method of heating a spraying material to a molten or semi-molten state by using a heat source, spraying and depositing the spraying material on the surface of a pretreated substrate at a certain speed to form a coating, and endowing the surface of the substrate with special properties.

Thermal spray coatings are composed of particles superimposed on one another, and voids necessarily exist between the superimposed particles, and these void defects are channels through which corrosive media rapidly diffuse, significantly reducing the corrosion resistance of the coating. In particular, the presence of the through pores allows corrosive media to reach the surface of the protected substrate through the pores, causing chemical or electrochemical erosion of the coating and the substrate, corrosion products to accumulate at the interface, cracking and peeling of the thermal spray coating, and ultimately leading to failure of the coating.

The main approach for solving the problem of pores in the thermal spraying coating is to adopt a hole sealing technology, namely, a hole sealing agent (generally organic material oily matter) is coated and permeates into the thermal spraying coating to plug the pores of the thermal spraying coating, so that the hole sealing treatment of the thermal spraying coating is realized.

However, there are two problems to be solved in the current field of coating sealing:

firstly, the pore sealing agent is limited by the structural stability of the organic matter, and the service temperature of the pore sealing agent of the pure organic matter component is limited (generally less than 300 ℃).

Secondly, the traditional hole sealing method is a normal pressure brush coating type, namely, the organic hole sealing agent is manually and uniformly brushed on the surface of the coating under the normal pressure environment, and the hole sealing agent permeates into the pores of the coating by depending on the self-fluidity. The normal-pressure brushing type hole sealing process has the following defects:

(1) the technical defects of the normal-pressure brushing type hole sealing process are as follows:

the normal-pressure brushing type hole sealing process has the defects of shallow penetration depth of a hole sealing agent and nonuniform penetration depth of the hole sealing agent, and the service life of a coating is restricted. The surface of the coating is continuously worn by the medium during the service period of the coating, once the wear amount exceeds the penetration depth of the sealant, the pores among the particles in the coating are exposed to the medium environment, the corrosive medium can reach the protected matrix through the pores, the coating is easy to peel off, and the corrosion resistance or sealing effect is lost.

1. The penetration depth of the hole sealing agent is shallow: under the normal pressure brushing process, the sealant permeates into tiny pores on the surface of the coating by means of self-fluidity, and because air remains in the pores and the self-fluidity of the sealant is limited, the sealant can only permeate to the shallow surface of the coating, and the general penetration depth is about 20 mu m.

General industrial experience shows that the coating on the surface of a rotating part of rotating mechanical equipment operating in a conventional medium environment can fall off within 1-3 years of service time, and the coating which is controlled improperly by a hole sealing process falls off and fails within 1 year of service.

2. The penetration depth of the sealant is not uniform: the normal-pressure brushing process is manually operated, and the experience and proficiency of operators and the geometric shape of the surface of a coating all influence the brushing uniformity of the sealant. If the thickness of the coating layer is not uniform, it may cause the penetration depth of the sealant to be shallower at the portion of the thin coating layer than at other portions. Industry experience has shown that the depth of penetration under the brush-coating process is 50% less at the shallowest depth than at the deepest depth. The penetration shallow part becomes the weak point of the service life of the coating and influences the service life of the coating.

(2) The normal-pressure brushing type hole sealing process has low production efficiency and is embodied in two aspects:

1. the curing time of the sealant is long: the sealant curing time refers to the time required for the sealant to brush on the surface of the coating until the sealant solidifies in the pores of the coating.

The normal-pressure brush-coating type hole sealing process depends on the fact that the self-fluidity of the hole sealing agent permeates into the pores of the coating, the fluidity of the hole sealing agent is generally poor, and the time consumption of the dynamic process that the hole sealing agent flows into and fills the pores is long. Industry experience has shown that cure times require at least 24 hours.

2. Difficult to automate: as mentioned above, the brush-coating hole sealing process is a manual operation activity, and the manual construction according to parts must be carried out by experienced personnel, and at present, the industrial automation process is not realized, so that the activity of carrying out high-efficiency thermal spraying construction on a large scale and in batches is restricted.

Disclosure of Invention

In view of the above, in order to overcome the defects of the prior art and achieve the above object, the present invention aims to provide a vacuum hole sealing device suitable for thermal spraying coatings, wherein the hole sealing of the thermal spraying coatings is performed by using the vacuum hole sealing device, the penetration depth of a hole sealing agent is deep, and the hole sealing effect is good.

In order to achieve the purpose, the invention adopts the following technical scheme:

the utility model provides a vacuum hole sealing equipment suitable for hot spraying coating for carry out the hole sealing to the hot spraying coating of coating part, vacuum hole sealing equipment include the container, with the sealant of container intercommunication stores jar, hot-water cylinder and vacuum pump, the container includes the box body of below and the closing cap of top, has seted up first opening, second opening and third opening on the lateral wall of box body, and fourth opening and fifth opening have been seted up to the bottom of box body, the sealant store jar with the container passes through second opening and fourth opening intercommunication, hot-water cylinder and container pass through third opening and fifth opening intercommunication, the vacuum pump passes through first opening with the container intercommunication, the vacuum pump is used for making it makes the sealant get into to form the negative pressure in the hole of hot spraying coating in the hole.

According to some preferred implementation aspects of the invention, the first opening and the second opening are located on the same side wall, the height of the second opening is lower than that of the first opening, and the third opening is located on the opposite side wall.

According to some preferred implementation aspects of the invention, the device comprises a pressurizing pump, the first opening is communicated with a pressurizing pipeline and a vacuum pipeline, the pressurizing pipeline is provided with the pressurizing pump and a first isolation valve, and the vacuum pipeline is provided with a vacuum pump and a second isolation valve.

According to some preferred embodiments of the present invention, the sealant storage tank has a sixth opening disposed on a sidewall thereof and a seventh opening disposed on a bottom, a sealant delivery conduit is disposed between the sixth opening and the second opening, and a sealant return conduit is disposed between the seventh opening and the fourth opening.

According to some preferred embodiment aspects of the present invention, a sealant delivery pump and a third isolation valve are disposed on the sealant delivery pipe, and a fourth isolation valve is disposed on the sealant return pipe.

According to some preferred implementation aspects of the invention, the hot water tank has an eighth opening provided on a side wall thereof and a ninth opening provided on a bottom, a hot water delivery pipe is provided between the ninth opening and the fifth opening, and a hot water return pipe is provided between the eighth opening and the third opening.

According to some preferred implementation aspects of the invention, the hot water delivery pipe is provided with a hot water circulation pump and a fifth isolation valve, and the hot water return pipe is provided with a sixth isolation valve.

The invention also provides a hole sealing method of the thermal spraying coating, which comprises the following steps: placing a coating component with a thermal spraying coating in a closed container, adding a hole sealing agent into the closed container, filling the hole sealing agent into the closed container, and controlling the closed container to be in a negative pressure state so that the hole sealing agent flows into pores in the coating; and discharging the hole sealing agent in the closed container, cleaning the coating part, taking out the coating part and drying.

According to some preferred embodiments of the invention, the sealing method further comprises a pressurizing step before discharging the sealing agent in the closed container, and specifically comprises the following steps: and after the pressure in the closed container is recovered to be normal pressure, pressurizing the closed container, and maintaining for a certain time. Namely, a positive pressure process is carried out after the negative pressure, so that the sealant can better enter the pores of the coating.

According to some preferred embodiments of the invention, the cleaning is to add water into the closed container and perform circulating cleaning, the temperature of the water is not lower than 85 ℃, so as to better clean the sealant remained on the surface of the coating part, and meanwhile, the organic components in the sealant are solidified and cured in the temperature environment of more than 85 ℃ to fill the pores in the coating.

In some embodiments of the present invention, the hole sealing method specifically includes the following steps:

A. and placing the coating component to be sealed in a closed container.

B. And feeding the liquid hole sealing agent into the closed container.

C. And pumping air in the container from the top of the closed container, finally filling the whole closed container with the hole sealing agent, and maintaining the container in a negative pressure state, wherein the negative pressure is maintained at 0-10 pa (absolute pressure) for 20-30 min. The negative pressure state can pump out air in the pores, which is helpful for the sealant to flow into the pores in the coating and reach deeper penetration depth.

D. The container is communicated with the atmosphere, and the pressure in the closed container is recovered to be normal pressure.

E. And pressurizing the inside of the closed container from the top of the closed container, wherein the pressure is maintained at 6-50 bar (absolute pressure) and the maintaining time is 20-30 min. The pressurization further forces the sealant to enter the pores inside the coating and reach a deeper penetration depth.

F. And discharging the hole sealing agent in the closed container.

G. And (3) communicating the closed container with a hot water tank, circulating hot water for about 10-15 min, and cleaning residual hole sealing agent adhered to the surface of the coating part, wherein the temperature of the hot water is not lower than 85 ℃. And under the heating of high-temperature water, the sealant remained in the pores of the coating is solidified and fills the pores.

H. And taking out the coating part and airing.

Compared with the prior art, the invention has the advantages that: according to the vacuum hole sealing equipment suitable for the thermal spraying coating, when hole sealing is carried out, the hole sealing agent can reach the penetration filling of the full coating thickness or the penetration thickness more than 100 microns, and the penetration depth is deep; hot water circulation cleaning and curing are adopted, so that the coating hole sealing efficiency is greatly improved; can realize automatic hole sealing assembly line in batches, improve hot spraying production efficiency greatly.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

FIG. 1 is a schematic view of a vacuum sealing apparatus according to a preferred embodiment of the present invention;

wherein: 1 container body, 2 container cover, 3 sealant, 41 first opening, 42 second opening, 43 third opening, 44 fourth opening, 45 fifth opening, 46 sixth opening, 47 seventh opening, 48 eighth opening, 49 ninth opening, 51 first isolation valve, 52 second isolation valve, 53 third isolation valve, 54 fourth isolation valve, 55 fifth isolation valve, 56 sixth isolation valve, 6 sealant storage tank, 7 sealant delivery pump, 8 hot water tank, 9 heater, 10 thermometer, 11 hot water, 12 flow meter, 13 pressure gauge, 14 pressure pump, 15 vacuum pump, 16 pressure pipe, 17 vacuum pipe, 18 sealant delivery pipe, 19 sealant return pipe, 20 hot water delivery pipe, 21 hot water return pipe, 22 hot water circulation pump.

Detailed Description

In order to make those skilled in the art better understand the technical solution of the present invention, the technical solution in the embodiment of the present invention will be clearly and completely described below with reference to the drawings in the embodiment of the present invention, and it is obvious that the described embodiment is only a part of the embodiment of the present invention, and not a whole embodiment. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Embodiment one hole sealing equipment

The vacuum hole sealing equipment suitable for the thermal spraying coating in the embodiment is used for sealing the thermal spraying coating of the coating component. Referring to fig. 1, the vacuum sealing apparatus includes a container, a sealing agent storage tank 6 communicated with the container, a hot water tank 8, a vacuum pump 15 and a pressure pump 14, the container includes a lower box body 1 and an upper sealing cover 2, a first opening 41, a second opening 42 and a third opening 43 are opened on a side wall of the box body 1, and a fourth opening 44 and a fifth opening 45 are opened at a bottom of the box body 1. The first opening 41 and the second opening 42 are located on the same side wall, the height of the second opening 42 is lower than that of the first opening 41, and the third opening 43 is located on the opposite side wall.

The sealant storage tank 6 has a sixth opening 46 provided in a side wall thereof and a seventh opening 47 provided in a bottom thereof, a sealant delivery pipe 18 is provided between the sixth opening 46 and the second opening 42, and a sealant return pipe 19 is provided between the seventh opening 47 and the fourth opening 44. The hole sealing agent conveying pipeline 18 is provided with a hole sealing agent conveying pump 7 and a third isolation valve 53, and the hole sealing agent return pipeline 19 is provided with a fourth isolation valve 54.

The hot water tank 8 has an eighth opening 48 provided on a side wall thereof and a ninth opening 49 provided on a bottom thereof, a hot water supply pipe 20 is provided between the ninth opening 49 and the fifth opening 45, and a hot water return pipe 21 is provided between the eighth opening 48 and the third opening 43. The hot water delivery pipe 20 is provided with a hot water circulation pump 22 and a fifth isolation valve 55, and the hot water return pipe 21 is provided with a sixth isolation valve 56.

The hot water tank 8 is also provided with a heater 9 and a thermometer 10 to further control the temperature of the hot water 11. The hot water return pipe 21 is provided with a flow meter 12 for controlling the flow rate of the hot water 11 during circulation.

The second opening 42 is communicated with a pressurizing pipeline 16 and a vacuum pipeline 17, the pressurizing pipeline 16 is provided with a pressurizing pump 14 and a first isolating valve 51, the vacuum pipeline 17 is provided with a vacuum pump 15 and a second isolating valve 52, and the tail ends of the pressurizing pipeline 16 and the vacuum pipeline 17 are communicated with the atmosphere.

The container is also provided with a pressure gauge 13, and the pressure in the container is observed in real time through the pressure gauge 13. And the pressure gauge 13 is in communication with the pressurizing pump 14 and the vacuum pump 15 to control the pressure inside the container by the pressurizing pump 14 and the vacuum pump 15.

Example two hole sealing method

The embodiment provides a method for sealing a thermal spray coating component based on the sealing device in embodiment 1, which specifically comprises the following steps:

A. the coating component to be sealed is placed in the box body 1 of the container, then the sealing cover 2 is covered to seal the container, and at the moment, all the isolation valves are closed. If the parts are heavy, it is conceivable to use a spreader such as a crane.

B. The third isolation valve 53 is opened, the fourth isolation valve 54 is closed, and the liquid sealant 3 is introduced into the closed container through the sealant delivery pump 7 on the sealant delivery pipe 18.

C. And (3) opening the vacuum pump 15 and the second isolation valve 52 on the vacuum pipeline 17, pumping air in the container from the top of the container through the first opening 41, and finally filling the sealing agent 3 in the whole closed container and maintaining the container in a negative pressure state. The pressure gauge 13 displays the pressure value in the container, the pressure value is confirmed to be 8pa (absolute pressure) through real-time monitoring, and the maintaining time is 30 min.

The negative pressure state can pump out air in the pores, which is helpful for the sealant 3 to flow into the pores inside the coating and reach deeper penetration depth.

D. The vacuum pump 15 is stopped, and the sealed container is communicated with the atmosphere through the second isolation valve 52 and the vacuum pump 15, so that the pressure in the container is recovered to the normal pressure.

E. The second isolation valve 52 is closed, the first isolation valve 51 on the pressurizing pipeline 16 is opened, the pressurizing pump 14 is operated, the pressurizing pipeline 16 is used for pressurizing the inside of the closed container, the pressure gauge 13 displays the pressure value in the container, the pressure is maintained at 10bar (absolute pressure), and the maintaining time is 30 min. Namely, a positive pressure process is carried out after the negative pressure, and the pressurizing operation can further force the sealant 3 to enter the inner pores of the coating and achieve deeper penetration depth.

F. And (3) stopping the pressure pump 14, opening the fourth isolation valve 54 on the hole sealing agent return pipeline 19, and discharging the hole sealing agent 3 out of the container through the hole sealing agent return pipeline 19 where the fourth isolation valve 54 is located by using the self gravity to enter the hole sealing agent storage tank 6.

G. Checking the thermometer 10, confirming that the temperature of the hot water 11 in the hot water tank 8 is 90 ℃, opening a fifth isolation valve 55 on the hot water conveying pipeline 20 and a sixth isolation valve 56 on the hot water return pipeline 21, connecting the container with the hot water tank 8, and starting a hot water circulating pump 22 on the hot water conveying pipeline 20, wherein the circulating time is 15 min. The surface of a coating part in the closed container is cleaned by hot water 11, the residual sealant 3 attached to the surface of the coating part is cleaned, and meanwhile, under the heating of high-temperature water, the organic components of the sealant 3 remained in the coating pores are solidified and fill the pores, so that the curing time of the sealant is shortened.

And C, after all the air in the pores is pumped away, the pores are in negative pressure, so that the sealant 3 in the pores cannot flow out, and the hot water 11 can only clean the residual sealant 3 adhered to the surface of the coating part.

H. The cover 2 of the container is opened, and the coating component is taken out and dried.

By adopting the hole sealing equipment and the hole sealing process, the hole sealing agent 3 can penetrate into the pores of the coating, the hole sealing effect is fully achieved, and the hole sealing maintaining effect is good.

The hole sealing process can be designed into a production line through the steps A to H, and automatic operation is realized.

The operation states of the main components in the hole sealing equipment in each step are shown in the following table:

by adopting the hole sealing equipment and the hole sealing method, for the coating prepared by the electric arc spraying process, the hole sealing method of the embodiment can realize 100% penetration filling of the full thickness, and the conventional normal-pressure brushing type hole sealing method can only penetrate to 20% of the thickness of the coating; for the coating prepared by the supersonic flame spraying process, the penetration depth of the coating prepared by the supersonic flame spraying process is improved by 40 percent compared with that of the normal-pressure brushing hole sealing method. Therefore, the penetration depth can be effectively increased by adopting the hole sealing equipment and the hole sealing method.

The hole sealing equipment and the hole sealing method have the following advantages:

(1) by adopting the hole sealing equipment and the corresponding hole sealing method, the penetration depth of the hole sealing agent is 5 times that of a normal-pressure brushing type hole sealing process, namely not less than 100 um; for the thermal spraying coating with the thickness less than 100um, the full-thickness penetration filling can be realized; greatly improving the service life of the coating.

(2) The hot water circulation cleaning and curing are adopted, the hole sealing curing time is shortened to 20% of that of the normal-pressure brush-coating type hole sealing process, namely, the hole sealing curing of a single coating part is not more than 5h, and the coating hole sealing efficiency is greatly improved.

(3) The automatic hole sealing assembly line for workpieces in batches can be realized, and the production efficiency of thermal spraying is greatly improved.

The above embodiments are merely illustrative of the technical concept and features of the present invention, and the purpose thereof is to enable those skilled in the art to understand the content of the present invention and implement the invention, and not to limit the scope of the invention, and all equivalent changes or modifications made according to the spirit of the present invention should be covered by the scope of the present invention.

Claims

1. A vacuum hole sealing equipment suitable for thermal spraying coating is used for sealing the thermal spraying coating of a coating component, and is characterized in that: vacuum hole sealing equipment include the container, with the hole sealing agent storage tank, hot-water cylinder and the vacuum pump of container intercommunication, the container includes the box body of below and the closing cap of top, has seted up first opening, second opening and third opening on the lateral wall of box body, and fourth opening and fifth opening have been seted up to the bottom of box body, hole sealing agent storage tank with the container passes through second opening and fourth opening intercommunication, hot-water cylinder and container pass through third opening and fifth opening intercommunication, the vacuum pump passes through first opening with the container intercommunication, the vacuum pump is used for making it makes the hole sealing agent get into to form the negative pressure in the hole of hot spraying coating in the hole.

2. The plugging apparatus according to claim 1, wherein: the first opening and the second opening are located on the same side wall, the height of the second opening is lower than that of the first opening, and the third opening is located on the other opposite side wall.

3. The plugging apparatus according to claim 1, wherein: including the force (forcing) pump, the intercommunication has pressurization pipeline and vacuum pipe on the first opening, be provided with on the pressurization pipeline force (forcing) pump and first isolation valve, be provided with on the vacuum pipe vacuum pump and second isolation valve.

4. The plugging apparatus according to claim 1, wherein: the hole sealing agent storage tank is provided with a sixth opening arranged on the side wall of the hole sealing agent storage tank and a seventh opening arranged on the bottom of the hole sealing agent storage tank, a hole sealing agent conveying pipeline is arranged between the sixth opening and the second opening, and a hole sealing agent backflow pipeline is arranged between the seventh opening and the fourth opening.

5. The plugging apparatus according to claim 4, wherein: the hole sealing agent conveying pipeline is provided with a hole sealing agent conveying pump and a third isolating valve, and the hole sealing agent return pipeline is provided with a fourth isolating valve.

6. The plugging apparatus according to claim 1, wherein: the hot water tank is provided with an eighth opening arranged on the side wall of the hot water tank and a ninth opening arranged on the bottom, a hot water conveying pipeline is arranged between the ninth opening and the fifth opening, and a hot water return pipeline is arranged between the eighth opening and the third opening.

7. The plugging apparatus according to claim 6, wherein: the hot water conveying pipeline is provided with a hot water circulating pump and a fifth isolating valve, and the hot water return pipeline is provided with a sixth isolating valve.

8. A hole sealing method of a thermal spraying coating is characterized by comprising the following steps: placing a coating component with a thermal spray coating in a container, adding a sealant into the container and filling the sealant into the container, and controlling the container to be in a negative pressure state so that the sealant flows into the interior of coating pores; and discharging the hole sealing agent in the container, cleaning the coating part, taking out the coating part and drying the coating part.

9. The pore sealing method according to claim 8, characterized in that: the hole sealing method also comprises a pressurizing step before the hole sealing agent in the container is discharged, and specifically comprises the following steps: after the pressure in the container is recovered to the normal pressure, the container is pressurized and maintained.

10. The pore sealing method according to claim 8, characterized in that: and the cleaning step is to add water into the container and perform circulating cleaning, wherein the temperature of the water is not lower than 85 ℃.