阅读说明：本技术 氟树脂涂膜泵工艺 (Fluororesin coating pump process ) 是由 康庆刚 于 2020-06-22 设计创作，主要内容包括：一种氟树脂涂膜泵工艺,其特征在于,包括以下步骤：(1)酸洗除垢；(2)高温去油污；(3)喷砂除锈；(4)清洗；(5)喷涂底层；(6)喷涂面层；(7)喷涂强化层。本发明专利的优点是：金属表面处理程度高,结合能力好；分底层和面层多次喷涂,均匀致密无缺陷,结合强度高；能够将含氟树脂涂装在泵内的全部过流面,不留死角；涂层最外层的硬化层提高涂层的表面强度。(A fluororesin coating pump process is characterized by comprising the following steps: (1) acid washing and descaling; (2) removing oil stains at high temperature; (3) sand blasting and rust removing; (4) cleaning; (5) spraying a bottom layer; (6) spraying a surface layer; (7) and spraying a strengthening layer. The invention has the advantages that: the metal surface treatment degree is high, and the binding capacity is good; the bottom layer and the surface layer are sprayed for multiple times, and the coating is uniform, compact and free of defects and high in bonding strength; the fluorine-containing resin can be coated on all the overflowing surfaces in the pump without dead angles; the hardened layer of the outermost layer of the coating improves the surface strength of the coating.)

1. A fluororesin coating pump process is characterized by comprising the following steps:

(1) acid washing and descaling;

(2) removing oil stains at high temperature;

(3) sand blasting and rust removing;

(4) cleaning;

(5) spraying a bottom layer;

(6) spraying a surface layer;

(7) and spraying a strengthening layer.

2. The fluororesin coating pump process according to claim 1, wherein the specific method for acid washing and descaling in step (1) is: the component is soaked or washed by acid water solution, the volume concentration of the acid water solution is 50-100%, and the pickling time is 10min after a scale layer on the surface of the component cannot be seen by naked eyes.

3. The fluororesin coating pump process according to claim 1, wherein the specific method for removing oil stains at high temperature in the step (2) is as follows: and (3) placing the component subjected to acid cleaning and descaling into a high-temperature furnace, automatically heating the temperature in the furnace from room temperature to 350 +/-10 ℃, keeping the temperature for more than 1h, and then discharging the component out of the furnace for air cooling.

4. The fluororesin coating pump process according to claim 1, wherein the step (3) is a concrete method for blasting rust removal: and carrying out full-surface sand blasting treatment on the component to remove deep corrosion and slag residue on the surface of the component.

5. The fluororesin coated pump process according to claim 1, wherein the cleaning in the step (4) is carried out by: the surface of the pump member was rinsed with ultrasonic waves and boiling water for more than 1 hour to remove any residue.

6. The fluororesin coating pump process according to claim 1, wherein the step (5) is a specific method of spraying a primer layer: preheating the cleaned component to 390 +/-10 ℃, and keeping the temperature for more than 0.5 h; spraying fluorine-containing resin primer on the surface of the member by using a high-pressure spray gun with the caliber of 0.3-0.8 mm and the pressure of not less than 0.6Mpa to form a fluorine-containing resin bottom layer; drying and sintering at constant temperature for more than 5 h; cooling to room temperature along with the furnace;

and (5) spraying a surface layer on the surface of the bottom layer in the step (6) by adopting the same method as the step (5).

7. The fluororesin coating pump process according to claim 6, wherein the spraying of the topcoat of step (6) is repeated a plurality of times depending on the specific coating thickness.

Technical Field

The invention relates to a fluororesin coating pump process, which is used for manufacturing a fluororesin coating with high bonding force on the surface of a metal workpiece of a pump.

Background

The fluororesin coating technology can achieve the capabilities of no scaling and no other media adhesion when applied to the surface of a metal component of the pump. However, the prior art has the disadvantage that the bonding force between the coating film and the pump component is insufficient, which is mainly reflected in that the coating is easy to fall off from the coated metal pump component. In particular, when rotating components (such as centrifugal pump impellers, vanes, etc.) are operated, cavitation erosion occurs on the surfaces of the rotating components, which is a complex phenomenon of fluid dynamics, materials science, and physics and chemistry, and is difficult to avoid, so that the coating life can be prolonged only by improving the bonding strength.

The insufficient bonding strength between the fluororesin coating film and the surface of the pump member is mainly caused by:

1. the surface of the metal pump piece is unqualified before spraying, and the combination is not in place due to dirt, oil stain and corrosion.

2. The liquid fluorine-containing resin has fluidity, permeability and surface tension, and can well wet the whole surface.

3. The fluorine-containing resin can not be uniformly sprayed in a narrow space in the flow surface of the pump, so that a flow channel is narrow and blocked, or spray leakage corrosion is caused.

4. The fluororesin coating layer has insufficient surface strength and is broken from the surface of the coating layer.

Disclosure of Invention

In order to overcome the defects in the prior art, the invention provides a fluororesin coating pump process.

The technical scheme of the invention is as follows: a fluororesin coating pump process is characterized by comprising the following steps: (1) acid washing and descaling; (2) removing oil stains at high temperature; (3) sand blasting and rust removing; (4) cleaning; (5) spraying a bottom layer; (6) spraying a surface layer; (7) and spraying a strengthening layer.

The invention has the advantages that: the problems of uneven coating and dead angles are effectively solved by spraying the liquid fluororesin; the problems of incomplete coating and dead angles are solved by spraying liquid polytetrafluoroethylene resin for many times. The liquid fluorine-containing resin is sprayed by a small-caliber high-pressure spray gun for multiple times, so that the liquid can uniformly cover and permeate the surfaces of all narrow spaces. The metal surface treatment degree is high, and the binding capacity is good; the bottom layer and the surface layer are sprayed for multiple times, and the coating is uniform, compact and free of defects and high in bonding strength; the fluorine-containing resin can be coated on all the overflowing surfaces in the pump without dead angles; the hardened layer of the outermost layer of the coating improves the surface strength of the coating.

Drawings

FIG. 1 is a schematic diagram of pickling and descaling by a soaking method adopted in the invention;

FIG. 2 is a schematic diagram of the present invention for descaling by acid washing using a rinsing method;

FIG. 3 is a temperature-time curve for high temperature degreasing according to the present invention;

FIG. 4 is a schematic of the cleaning apparatus and method of the present invention:

FIG. 5 is a temperature-time curve for spray coating of a primer layer and a topcoat in accordance with the present invention;

FIG. 6 is a temperature-time curve of a spray hardened layer of the present invention.

Description of reference numerals: 1. the method comprises the following steps of (1) a container, 2) an acid pickling solution, 3, a component, 4, an ultrasonic generator, 5, boiling water, a heating section, b, a constant-temperature preheating section, c, a bottom layer (surface layer) spraying section, d, a constant-temperature drying section, e, a cooling section, f, a hardening layer spraying section and g, a high-temperature deoiling constant-temperature section.

Detailed Description

Referring to fig. 1-6, the invention is a fluororesin coating pump process, which comprises the whole process procedures of acid cleaning and descaling 1, high-temperature degreasing 2, sand blasting and derusting 3, cleaning 4, spraying a bottom layer 5, spraying a surface layer 6 and spraying a hardened layer 7.

The specific method for acid washing and descaling in the step (1) comprises the following steps: soaking (soaking method shown in figure 1) or washing (washing method shown in figure 2) the component with weak acid aqueous solution, wherein the concentration of the weak acid aqueous solution is 50% -100%, and the pickling time is 10min after the scale layer on the surface of the component is invisible to naked eyes; the weak acid comprises hydrochloric acid or oxalic acid.

The technical effects of the acid washing and descaling in the step (1) of the invention are explained as follows: the carbonate is common, and because the carbonate has very low solubility, the calcium and magnesium in water exist mostly in the form of bicarbonate, and the bicarbonate has the following equilibrium relationship with the carbonate and carbon dioxide:

Ca(HCO₃)＝＝＝CaCO₃+CO₂↑+H₂O

Mg(HCO₃)＝＝＝MgCO₃+CO₂↑+H₂O

carbonate scale is generated as a result of temperature or other factors moving the equation to the right. The reaction mechanism is as follows (with HCl and HNO)₃For example):

Ca(HCO₃)+2HCL→CaCO₃+CO₂↑+H₂O

Mg(HCO₃)+2HCL→MgCO₃+CO₂↑+H₂O

Ca(HCO₃)+2HNO₃→Ca(NO₃)₂+CO₂↑+H₂O

Mg(HCO₃)+2HNO₃→Mg(NO₃)₂+CO₂↑+H₂O

besides rust, the reaction mechanism is as follows (taking hydrochloric acid as an example):

FeO+2HCl→FeCl₂+H₂O

Fe₂O₃+6HCl→2FeCl₃+3H₂O

Fe2O₄+8HCl→2FeCl₃+FeCl₃+4H₂O

the generated ferrous chloride and ferrous trichloride can be dissolved in the solution, and meanwhile, the acid solution can react with the steel matrix as follows:

FeO+2HCl→FeCl₂+2[H]

2[H]→H2↑

the generated hydrogen plays a role in mechanical stripping and shedding of scale and hydride which are difficult to dissolve, and is beneficial to descaling.

In the cleaning and descaling process, because acid reacts with scale to generate carbon dioxide and hydrogen, the insoluble sulfate scale, silica scale and the like are dissolved with a large amount of carbonate scale and then become loose residue pieces which automatically fall off or are pneumatically washed off by washing, and meanwhile, the insoluble calcium and magnesium salts automatically fall off and are washed off.

Referring to fig. 3, the specific method for removing oil stain at high temperature in step (2) is as follows: and (3) placing the component subjected to acid cleaning and descaling into a high-temperature furnace, automatically heating the temperature in the furnace from room temperature to 350 +/-10 ℃, keeping the temperature for more than 1h, and then discharging the component out of the furnace for air cooling (naturally cooling to room temperature).

The oil stain has permeability on the metal surface, deep oil stain is difficult to clean, the oil stain can be volatilized rapidly at 350 +/-10 ℃, the infiltration amount is limited, the oil stain is cleaned by acid cleaning in the previous period, the residual oil is very little, and the oil stain is volatilized completely in the temperature rise process. But in order to ensure that the surface is clean and no oil stain is left, the high-temperature oil stain removal method is adopted to ensure the process quality, the components can be internally soaked at constant temperature for one hour, the oil stain is continuously promoted to be completely volatilized, and the possibility that the oil stain is not left is ensured! The air cooling of tapping is in order to let the component break away from by the environmental space of oil smoke pollution, and component temperature slowly reduces gradually in the air cooling in-process, so surface oil smoke pollution can be thoroughly volatilized, thoroughly keeps away from the greasy dirt.

The concrete method for sand blasting and rust removing in the step (3) comprises the following steps: and carrying out full-surface sand blasting treatment on the component to remove deep corrosion and slag residue on the surface of the component.

Referring to fig. 4, the method for cleaning in step (4) is as follows: boiling water 5 is provided in the vessel 1, an ultrasonic generator 4 is provided at the bottom of the vessel 1, the component 3 is placed in the boiling water 5, and any residue on the surface of the component 3 is removed by immersion cleaning using ultrasonic waves and the boiling water.

Referring to fig. 5, the step (5) is a specific method for spraying the primer layer: preheating the cleaned component to 390 +/-10 ℃, and keeping the temperature for more than 0.5 h; spraying liquid fluororesin (without limitation) or fluororesin powder on the surface of the member by using a high-pressure spray gun with the caliber of 0.3-0.8 mm and the pressure of not less than 0.5Mpa to form a coating bottom layer; drying and sintering at constant temperature for more than 5 h; cooling to room temperature along with the furnace.

And (5) spraying a surface layer on the surface of the bottom layer in the step (6) by adopting the same method as the step (5).

And (4) repeating the step (6) of spraying the surface layer for multiple times according to the specific coating thickness to form multiple layers of surface layers until the required thickness is reached.

The spraying of the bottom layer can be carried out for multiple times according to the specific thickness requirement. The bottom layer is in contact with the surface of the component, and the bottom layer is used for filling the rough surface and the tiny defects of the component on the basis of fully covering the surface of the component, so that a good stress layer is formed on the surface of the component.

The spraying hardening layer can be carried out for multiple times according to specific thickness requirements until the required thickness is reached.