CN112642680A

CN112642680A - Surface powder coating spraying process of metal separation net

Info

Publication number: CN112642680A
Application number: CN202011451562.XA
Authority: CN
Inventors: 舒建兵
Original assignee: Shanghai Techlab Metal Fence Co ltd
Current assignee: Shanghai Techlab Metal Fence Co ltd
Priority date: 2020-12-10
Filing date: 2020-12-10
Publication date: 2021-04-13

Abstract

The application discloses a surface powder coating spraying process of a metal separation net, which comprises the following steps: pre-treating; drying: drying the metal isolation net; powder spraying: spraying powder coating on the surface of the metal isolation net in an electrostatic spraying mode; and (3) curing: and curing the sprayed metal isolation net in a heating mode, wherein the curing temperature and the curing time are in direct proportion to the thickness of the metal isolation net, and the curing temperature or the curing time is adjusted according to the thickness of the metal isolation net. According to the method, the curing temperature and the curing time are adjusted according to the thickness of the metal isolation net, so that the optimal powder coating curing effect is achieved, the spraying operation steps are simplified, the problems that the powder coating adhesion and the curing corrosion prevention effect are unstable and the spraying process is complex to operate in the prior art are solved, and the high finished product qualification rate is guaranteed.

Description

Surface powder coating spraying process of metal separation net

Technical Field

The application relates to the technical field of fences, in particular to a surface powder coating spraying process of a metal isolation net.

Background

The fence is common outdoor protection equipment, is generally used in places such as highways, stadiums, parks, construction sites and the like, and has the functions of separating the places and warning and preventing burglary. The existing fence structure generally comprises metal separation nets and net sheets arranged between the metal separation nets, particularly, the metal separation nets are generally made of metal materials and are prone to rusting and corrosion after being exposed to an open environment for a long time, so powder paint is generally sprayed on the surface of the fence.

For example, the Chinese patent application with the publication number of CN110142192A discloses a spraying method of a two-in-one composite coating for a metal isolation net and a corrugated guardrail plate of a highway guardrail, and relates to the technical field of spraying methods. According to the technical scheme, the metal isolation net to be sprayed can be effectively degreased, derusted and decontaminated by carrying out spraying pretreatment during spraying; and by adopting a silane treatment process, the surface of the metal isolation net to be sprayed is sealed and a continuous, complete and compact composite film is formed, so that the spraying effect of the surface of the metal isolation net is improved.

However, in the above technical scheme, the spraying process includes pre-treatment of spraying, drying and preheating, primary spraying, primary curing, primary forced cooling, secondary spraying, secondary curing and secondary forced cooling, so that the purposes of improving the coating adhesion and curing corrosion prevention effect can be achieved, the operation steps are complicated, the processes of primary spraying and secondary spraying are not strictly limited, the sprayed finished product can not reach the expected effect, and the qualified rate of the finished product is not high.

Disclosure of Invention

The application aims to provide a surface powder coating spraying process of a metal separation net, and the problems that in the prior art, the powder coating is unstable in adhesive force and curing and corrosion prevention effect, and the spraying process is complex to operate are solved.

In order to achieve the above purpose, the embodiments of the present application adopt the following technical solutions: a surface powder coating spraying process of a metal separation net comprises the following steps:

pretreatment: sequentially carrying out pre-degreasing, main degreasing, primary water washing, secondary water washing, tertiary water washing, vitrification treatment, fourth water washing and fifth water washing on the metal isolation net, wherein degreasing agents with the same concentration are adopted for the pre-degreasing and the main degreasing to carry out degreasing treatment on the surface of the metal isolation net, industrial tap water is adopted for the primary water washing, the secondary water washing, the third water washing and the fourth water washing to carry out water washing on the surface of the metal isolation net, and a vitrification agent is adopted for the vitrification treatment to form a vitrification membrane on the surface of the metal isolation net; washing the surface of the metal isolation net with pure water for five times;

drying: drying the metal isolation net;

powder spraying: spraying powder coating on the surface of the metal isolation net in an electrostatic spraying mode;

and (3) curing: and curing the sprayed metal isolation net in a heating mode, wherein the curing temperature and the curing time are in direct proportion to the thickness of the metal isolation net, and the curing temperature or the curing time is adjusted according to the thickness of the metal isolation net.

In the technical scheme, the curing temperature and the curing time are adjusted according to the thickness of the metal isolation net so as to achieve the best powder coating curing effect, the spraying operation steps are simplified, the problems of unstable powder coating adhesion, curing and corrosion prevention effects and complex spraying process operation in the prior art are solved, and the high finished product qualification rate is ensured.

Further, according to the embodiment of the present application, wherein, in the pre-treatment step, the free alkali concentration of the degreasing agent used for pre-degreasing is 8-10 o/ml, the temperature is 20-40 ℃, and the time is 1-2 minutes.

Further, according to the embodiment of the present application, wherein, in the pre-treatment step, the free alkali concentration of the degreasing agent used for the main degreasing is 6-8 o/ml, the temperature is 20-40 ℃, and the time is 2-5 minutes.

Further, according to the examples of the present application, wherein, in the pre-treatment step, the pH of the industrial tap water is 8 to 10.

Further, according to the embodiment of the present application, wherein, in the pre-treatment step, the concentration of the vitrification agent is 3 to 7%.

Further, according to the examples of the present application, wherein, in the pre-treatment step, the pH of the vitrification agent is 4.5 to 5.5.

Further, according to the embodiment of the present application, wherein, in the pre-treatment step, the time period of the vitrification treatment is 3 to 6 minutes.

Further, according to the examples of the present application, wherein, in the pre-treatment step, the pH of the pure water is 6 to 8.

Further, according to the embodiment of the present application, wherein, in the pre-treatment step, the time length of the first water washing, the second water washing, the third water washing, the fourth water washing and the fifth water washing is 1-2 minutes.

Further, according to the embodiment of the application, in the drying step, the drying temperature is 95-105 ℃, and the drying time is 10-30 minutes.

Further, according to the embodiment of the present application, wherein, in the curing step, the curing temperature is 200-.

Further, according to an embodiment of the present application, wherein in the curing step, the curing temperature is inversely proportional to the curing time for the same thickness of the metal separation net.

Further, according to the embodiment of the present application, wherein in the curing step, the curing temperature is increased by 10-15 ℃ for each 0.5-1mm increase of the thickness of the metal separation net under the condition of the same curing time length.

Further, according to the embodiment of the application, in the curing step, under the condition of the same curing temperature, the curing time is increased by 1-5 minutes for every 3-5mm of the thickness of the metal separation net.

Further, according to the embodiment of the application, the metal separation net moves between the processes of the steps through the conveying of the hanging conveying chain, the conveying speed of the hanging conveying chain is linear speed, the curing time is in inverse proportion to the linear speed, and the curing time is controlled by adjusting the linear speed.

Further, according to the embodiment of the application, the linear speed is 15-40 HZ.

In order to achieve the purpose, the embodiment of the application also discloses a metal separation net, wherein the surface of the metal separation net is provided with a powder coating, and the powder coating is formed by spraying through the powder coating spraying process.

In order to achieve the purpose, the embodiment of the application also discloses a fence, which is characterized in that the fence is provided with the metal isolation net.

Compared with the prior art, the method has the following beneficial effects: according to the method, the curing temperature and the curing time are adjusted according to the thickness of the metal isolation net, so that the optimal powder coating curing effect is achieved, the spraying operation steps are simplified, the problems that the powder coating adhesion and the curing corrosion prevention effect are unstable and the spraying process is complex to operate in the prior art are solved, and the high finished product qualification rate is guaranteed.

Drawings

Fig. 1 is a flow chart of a powder spraying process for the surface of a metal separation net in the present application.

Fig. 2 is a flow chart of a pretreatment step in the powder spraying process of the surface of the metal separation net in fig. 1.

Figure 3 is a schematic structural view of a lifting tool of the present application.

Fig. 4 is a sectional view of fig. 3.

Fig. 5 is a normal force-bearing schematic diagram of the fixing mechanism in fig. 3.

Fig. 6 is a schematic force diagram of the hoisting tool during loading and unloading of the metal separation net.

In the attached drawings

1. Upright post

2. Hoisting tool 21, housing 211, and accommodating chamber

212. Side wall 213, limiting part 22, and turntable

221. Mounting groove 23, fixing mechanism 231 and slider

232. First connecting rod 234, fixed block 235 and second connecting rod

236. Baffle 24, main shaft 241 and mounting seat

233. Guide post

3. Lifting lug

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention clear and fully described, embodiments of the present invention are further described in detail below with reference to the accompanying drawings. It is to be understood that the specific embodiments described herein are merely illustrative of some embodiments of the invention and are not limiting of the invention, and that all other embodiments obtained by those of ordinary skill in the art without the exercise of inventive faculty are within the scope of the invention.

In the description of the present invention, it should be noted that the terms "center", "middle", "upper", "lower", "left", "right", "inner", "outer", "top", "bottom", "side", "vertical", "horizontal", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present invention. Furthermore, the terms "a," "an," "first," "second," "third," "fourth," "fifth," and "sixth" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

For the purposes of simplicity and explanation, the principles of the embodiments are described by referring mainly to examples. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the embodiments. It will be apparent, however, to one skilled in the art that the embodiments may be practiced without these specific details. In some instances, well-known methods and structures have not been described in detail so as not to unnecessarily obscure the embodiments. In addition, all embodiments may be used in combination with each other.

Fig. 1 is a flow chart of a powder spraying process for the surface of a metal separation net in the application, and fig. 2 is a flow chart of a pretreatment step in the spraying process. As shown in fig. 1-2, the powder spraying process for the surface of the metal isolation net comprises the following steps:

drying: drying the metal isolation net;

and (3) curing: and curing the sprayed metal isolation net in a heating mode, wherein the curing temperature or the curing time is in direct proportion to the thickness of the metal isolation net, and the curing temperature and the curing time are adjusted according to the thickness of the metal isolation net.

In contrast, the curing temperature and the curing time are adjusted according to the thickness of the metal isolation net so as to achieve the best powder coating curing effect, the spraying operation steps are simplified, the problems that the powder coating adhesion and the curing corrosion prevention effect are unstable and the spraying process is complex to operate in the prior art are solved, and the high finished product yield is guaranteed.

In the pretreatment step, grease and dirt on the surface of the metal isolation net are removed through the pre-degreasing and main degreasing functions, and the pre-degreasing operation is performed before the main degreasing, so that consumption of main degreasing raw materials can be reduced, and a better degreasing effect is guaranteed. The pre-degreasing and the main degreasing may be performed by soaking or spraying, and in the present application, in order to seek a better degreasing effect, a soaking method is preferably used. Specifically, a first groove and a second groove are respectively arranged on the pre-degreasing process and the main degreasing process, the groove amount of the degreasing agent in the first groove and the second groove is 0.3-3%, and the soaking temperature is 20-40 ℃.

In addition, the degreasing agent can adopt Ridoline1022R, Ridoline1020S or a mixture of the two, wherein the mixing ratio of the Ridoline1022R, the Ridoline1020S or the mixture of the Ridoline and the Ridoline is 10: 1. Wherein, in order to ensure the degreasing effect, the concentration of free alkali of the degreasing agent is preferably 8-10 points/ml and the soaking time is 1-2 minutes during pre-degreasing; in the main degreasing, the concentration of free alkali of the degreasing agent is preferably 6-8 o/ml, and the soaking time is 2-5 minutes. In this application, the free base concentration of the degreaser needs to be monitored and adjusted in time. The monitoring method comprises the following steps of sampling and detecting the concentration of free alkali in the degreasing agent once every four hours, and specifically comprises the following steps: and (3) adding 5 drops of phenolphthalein indicator into 10 ml of tank liquor, titrating with 0.1N sulfuric acid until pink disappears, and taking the number of ml of used group solution as the number of free alkali points. The adjustment method is that 80kg Ridoline1022R and 8kg Ridoline1020S are added into the first groove or the second groove, namely, the concentration of free alkali in the degreasing agent is increased by a point.

After degreasing is finished, the degreasing agent on the surface of the metal isolation net is washed away through primary washing, secondary washing and tertiary washing. The primary washing, the secondary washing and the tertiary washing are all carried out at normal temperature in a spraying or soaking mode, and the soaking mode is preferably adopted. Specifically, a third tank, a fourth tank and a fifth tank are respectively arranged on the primary washing procedure, the secondary washing procedure and the tertiary washing procedure, and the pH value of the industrial tap water is 8-10. The industrial tap water in the fifth tank can continuously overflow into the fourth tank, the industrial tap water in the fourth tank can continuously overflow into the third tank, and the industrial tap water in the third tank can continuously overflow and be discharged, so that the consumption of the industrial tap water can be saved, and the pH value of the industrial tap water can be adjusted.

In addition, the ceramic treatment has the effect of forming a ceramic film on the surface of the metal isolation net, and providing-OH groups on the surface of the metal isolation net after film formation to perform chemical reaction with coating groups, so that the adhesive force of the powder coating is improved, and the curing corrosion-resistant effect is enhanced. The vitrification treatment can be carried out in a spraying and soaking mode, and preferably in a soaking mode based on the vitrification effect and the consideration of saving raw materials, and the soaking time is 3-6 minutes. Specifically, a sixth tank is provided in the vitrification treatment step, and the amount of the vitrification agent to be contained in the sixth tank is 3%.

Wherein the adopted vitrification agent is Bonderite HC-1 from Hanbang, Germany, the concentration is 3-7 percent, and the pH value is 4.5-5.5. In this application, the pH of the vitrification agent needs to be detected and adjusted in time. The detection method comprises the following steps: the bath solution was filtered through Whatman42 filter paper, 10 ml of the bath solution was accurately pipetted with a 10 ml pipette into a 205 ml Erlenmeyer flask, 20 ml of a buffer solution with pH 1.4 was added, less than xylenol orange indicator was added, the flask was heated to 80-90 ℃ on a hotplate, and the solution was titrated with 1mmol/LEDTA standard solution while hot, the titration end point was the point at which the solution changed from magenta to bright yellow, whereby the concentration (%) of BonderiteHC-1 was calculated as (x-0.3209)/1.2738, where x is the number of ml of 1mmol/LEDTA standard solution consumed. The adjusting method comprises the following steps: 200kg of Bonderite HC-1 solution was added to the sixth tank, increasing the concentration by 1%; 2520 was added to lower the pH and N700 was added to raise the pH.

The vitrified agent remained on the surface of the metal isolation net is washed by four times of water, and the four times of water washing can be carried out by adopting a spraying or soaking mode, preferably a soaking mode. Specifically, a seventh tank is provided in the fourth washing step, in which the parameters of the industrial tap water are the same as those of the first washing, and the pH is adjusted by continuous overflow discharge.

The last procedure of the pretreatment is five times of water washing, which is used for replacing the ionized water on the surface of the metal isolation net and reducing the residue of the light metal. The five times of water washing is carried out in a spraying or soaking mode, and the soaking mode is preferably adopted. Specifically, the fifth washing step is provided with an eighth tank in which pure water has a pH of 6 to 8, and the pure water continuously overflows into the seventh tank, and the pH is adjusted by replenishing the water for the fourth washing step.

In addition, the drying step is to dry the moisture on the surface of the metal isolation net, the drying temperature is 95-105 ℃, the drying time is 10-30 minutes, and the subsequent powder spraying treatment is convenient.

After the powder spraying is finished, the powder coating needs to be cured, and in the application, the determination of the curing temperature and the curing time is related to the thickness of the metal separation net. Specifically, for metal separation nets of the same thickness, the curing temperature is inversely proportional to the curing time; under the condition of the same curing time, the curing temperature is increased by 10-15 ℃ when the thickness of the metal isolation net is increased by 0.5 mm; under the condition of the same curing temperature, the curing time is increased by 1-5 minutes when the thickness of the metal separation net is increased by 3-5 mm. According to the method, the curing temperature and the curing time are adjusted according to the thickness of the metal isolation net, so that the optimal powder coating curing effect is achieved, the spraying operation steps are simplified, the problems that the powder coating adhesion and the curing corrosion prevention effect are unstable and the spraying process is complex to operate in the prior art are solved, and the high finished product qualification rate is guaranteed. Preferably, the curing temperature is 200-. The above-mentioned curing temperature and curing time are adjusted based on the standard that a metal separation net with a thickness of 1mm is subjected to curing treatment at 200 ℃ for 10 minutes.

In addition, in the present application, the metal separation net is moved between the processes of the respective steps by the suspended conveyor chain, and the conveying speed of the suspended conveyor chain is the linear speed, so that the curing time period is inversely proportional to the linear speed, and the curing time period can be controlled by adjusting the linear speed. Preferably, the linear velocity is 15-40 Hz.

The fence metal isolation net sprayed by the process has good powder coating adhesive force and curing and corrosion preventing effects.

The present application will be described below by way of examples 1 to 10 and comparative examples 1 to 4, but the present application is not limited to these examples. In which table 1 shows the thickness, curing temperature and curing time of the metal separation net (i.e., metal separation net) in examples 1 to 10 and comparative examples 1 to 4.

TABLE 1

In this example, the coating performance test was performed on the above examples and comparative examples according to the test standard in GB/T26941.1-2011, and the test results are shown in Table 2.

In addition, the process can also be used for spraying the surface of the stand column, but the structure of the stand column is different from that of the metal isolation net, and a special hoisting tool is needed for assisting in spraying.

Further, this application connects the stand and hangs the conveying chain through lifting device 2 as shown in fig. 3, lifting device 2 the lower extreme stretch into the inside of stand 1 and with stand 1 fixed connection, be provided with lug 3 on lifting device 2's top, be connected with hanging the conveying chain through lug 3. By using the hoisting tool 2, on one hand, the outer side surface of the upright post 1 is not shielded, so that the powder coating effect is not influenced; on the other hand, this lifting device 2 can drive stand 1 rotatory around its self center pin at the removal in-process, further ensures the effect of application.

In particular, fig. 4 is a partial cross-sectional view of fig. 3, and as shown in fig. 3-4, the lifting tool 2 includes a housing 21, a turntable 22, a fixing mechanism 23, and a spindle 24.

Wherein, the upper end of the shell 21 is closed, the lower end is provided with an opening, and the lifting lug 3 is fixedly arranged on the upper end surface. The housing 21 has a receiving cavity 211 therein, and the receiving cavity 211 is used for mounting the motor. The inner side of the sidewall 212 of the housing 21 is provided with a position-limiting part 213, the outer contour of the position-limiting part 213 matches with the accommodating cavity, and the center is provided with a circular hole.

The rotary plate 22 is disposed at a lower end of the housing 21 and connected to a motor in the receiving cavity 211, and the rotary plate 22 is driven to rotate by the motor. The middle of the turntable 22 is provided with an annular mounting groove 221, the mounting groove 221 is matched with the limiting part 213, that is, the limiting part 213 is mounted in the mounting groove 221, and the mounting groove 221 is clamped on the periphery of the limiting part 213.

The main shaft 24 is arranged at the center of the turntable 22, the lower end of the main shaft 24 extends into the inner side of the upright post 1, the lower end of the main shaft 24 is provided with an installation seat 241, and the installation seat 241 is provided with an installation groove.

The fixing mechanism 23 is mounted on the main shaft 24 and includes a slider 231, a first link 232, a fixed block 234, a second link 235, and a baffle 236. Specifically, the sliding block 231 is installed between the installation groove 221 and the limiting portion 213, and an elastic member is disposed on one side of the sliding block 231, which is close to the limiting portion 213. In the normal state, the elastic member is in a slightly contracted state; when the slider 231 moves toward the stopper 213, the elastic member is pressed. The number of the sliding blocks 231 is at least 2, and the sliding blocks are uniformly distributed in the mounting groove 221. One end of the first connecting rod 232 is hinged to the sliding block 231, and a moving groove is formed in the lower end of the rotating disc 22, and the first connecting rod 232 extends out of the moving groove. The width of the moving slot is smaller than that of the slider 231, so that the slider 231 is prevented from falling from the moving slot. The moving slot is perpendicular to the side wall 212 of the housing 21. The fixing block 234 is fixedly installed in the middle of the main shaft 24, a guide hole is formed in the fixing block 234, a guide post 233 is installed in the guide hole, and the guide post 233 can move up and down in the guide hole. The upper end of the guide column 233 is hinged with the other end of the first connecting rod 232. One end of the second link 234 is hinged with the lower end of the guide column 233. The baffle 236 is T-shaped and has a plane perpendicular to each other and a mounting portion, the mounting portion is mounted in a mounting groove of the mounting base 241, and the mounting portion is hinged with the other end of the second connecting rod 234. The number of the sliding blocks 231, the first connecting rods 232, the guide posts 233, the second connecting rods 235 and the baffles 234 is consistent and in one-to-one correspondence.

In the above technical solution, when the hoisting device 2 is installed on the column 1, the elastic member located between the sliding block 231 and the limiting portion 213 applies an elastic force to the sliding block 231, the sliding block 231 applies a downward pressure to the guide post 233 through the first connecting rod 232, the guide post 233 applies an outward force to the baffle 236 through the second connecting rod 23, and the plane of the baffle 236 abuts against the inner side wall of the column 1, so that the hoisting device 2 is fixed to the column 1. The specific stress situation is shown in fig. 5.

When the upright 1 is to be assembled and disassembled, an outward force is applied to the first connecting rod 232 (i.e., the first connecting rod 232 is pulled outward), or an inward force is applied to the second connecting rod 235 (i.e., the second connecting rod 235 is pushed inward), so that the sliding block 231 extrudes the elastic member and moves towards the limiting portion 213, and the baffle 234 displaces towards the main shaft direction, thereby realizing the assembly and disassembly of the upright 1.

Although the illustrative embodiments of the present application have been described above to enable those skilled in the art to understand the present application, the present application is not limited to the scope of the embodiments, and various modifications within the spirit and scope of the present application defined and determined by the appended claims will be apparent to those skilled in the art from this disclosure.

Claims

1. A surface powder coating spraying process of a metal separation net is characterized by comprising the following steps:

pretreatment: sequentially carrying out pre-degreasing, main degreasing, primary washing, secondary washing, tertiary washing, vitrification treatment, fourth washing and fifth washing on the metal isolation net, wherein degreasing agents with the same concentration are adopted for the pre-degreasing and the main degreasing to carry out degreasing treatment on the surface of the metal isolation net, industrial tap water is adopted for the primary washing, the secondary washing, the third washing and the fourth washing to carry out washing on the surface of the metal isolation net, and a vitrification agent is adopted for the vitrification treatment to form a vitrification membrane on the surface of the metal isolation net; the fifth washing step is to wash the surface of the metal isolation net by pure water;

drying: drying the metal isolation net;

2. The process of claim 1, wherein in the pre-treatment step, the concentration of free alkali in the degreasing agent used for pre-degreasing is 8-10 o/ml, the temperature is 20-40 ℃, and the time is 1-2 minutes.

3. The process of claim 1, wherein in the pre-treatment step, the concentration of free alkali in the degreasing agent used for the main degreasing is 6-8 o/ml, the temperature is 20-40 ℃, and the time is 2-5 minutes.

4. The process of claim 1, wherein the tap water has a pH of 8-10 in the pre-treatment step.

5. The process of claim 1, wherein the concentration of the vitrification agent is 3 to 7% in the pre-treatment step.

6. The process of claim 1, wherein the pH of the vitrification agent is 4.5 to 5.5 in the pretreatment step.

7. The process of claim 1, wherein the ceramic treatment is performed for 3 to 6 minutes in the pretreatment step.

8. The process of claim 1, wherein the pH of the pure water is 6 to 8 in the pretreatment step.

9. The process of claim 1, wherein the time period of the first water washing, the second water washing, the third water washing, the fourth water washing and the fifth water washing in the pretreatment step is 1-2 minutes.

10. The process of claim 1, wherein the drying step is carried out at a temperature of 95-105 ℃ for 10-30 minutes.