Method for prolonging service life of water diaphragm pump

Abstract

The invention provides a method for prolonging the service life of a water diaphragm pump, which comprises the following steps: pretreating a water diaphragm pump pipeline inner wall material, observing and analyzing a workpiece after plasma electrolytic oxidation (PEO), and finally packaging and storing the water diaphragm pump pipeline inner wall material. According to the method, plasma electrolytic oxidation is carried out on the inner wall material (such as titanium alloy) of the water diaphragm pump pipeline, so that the wear resistance and corrosion resistance of the inner wall material of the water diaphragm pump pipeline are improved, the structural integrity of the pipeline is protected, and the stable medium conveying performance is maintained. And the method plays a crucial role in prolonging the service life of the water diaphragm pump and the pipeline thereof. The invention is mainly applied to the field of pump equipment.

Description

Technical Field

[0001] The invention belongs to the field of pump equipment, and in particular relates to a method for extending the service life of a water diaphragm pump. Background Art

[0002] The water diaphragm pump is developed on the basis of the water isolation pump (also known as the ball isolation pump) and the diaphragm pump (i.e., the Qihao pump). This pump combines the dual characteristics of the large flow of the water isolation pump and the high head of the diaphragm pump, with a maximum flow of 800 m3 / h and a maximum head of 10MPa. Due to the use of membrane isolation, there is no water consumption and no slurry mixing. Since the transmission medium is clean water, there is no oil consumption, so it also abandons the drawbacks of large water consumption of the water isolation pump, occasional slurry mixing, fast damage of the clean water pump, and oil consumption and environmental pollution of the isolation pump. Because of its excellent performance, the water diaphragm pump is widely used in the transportation of tailings and concentrates in ferrous and non-ferrous metal mines, chemical raw materials and other corrosive media.

[0003] The market demand for excellent pump equipment such as water diaphragm pumps has soared. After a large number of market evaluation feedback, water diaphragm pumps are unique in the performance of conveying high-concentration tailings slurry. Titanium alloy has good corrosion resistance and high strength. Therefore, it is widely used in the inner wall material of pump equipment pipelines. However, high-concentration tailings slurry contains a high proportion of solid particles. During transportation, the solid particles in the slurry flow at high speed, causing wear on the inner wall of the pipeline, and long-term operation may cause pipeline leakage; and high-concentration tailings may contain corrosive substances such as sulfides and cyanides. Long-term slurry transportation will cause corrosion of the inner wall of the pipeline. The wear and corrosion of the inner wall of the pipeline makes the inner wall of the pipeline rough and uneven, increasing the resistance to the flow of the slurry, and the flow rate of the slurry will decrease; pressure loss may occur in areas with severe local wear or corrosion, which requires the water diaphragm pump to overcome greater resistance to transport water to the specified height or distance, resulting in a reduction in the actual head that can be achieved. Due to the changes in flow and head caused by wear and corrosion on the inner wall of the pipeline, the water diaphragm pump needs to adjust the working state more frequently to maintain stable transportation. This frequent adjustment will cause the diaphragm to bear more irregular pressure changes, accelerating the fatigue damage of the diaphragm. Therefore, solving the wear and corrosion problems of the inner wall of the pipeline becomes the key to extending the life of the water diaphragm pump. Summary of the invention

[0004] Plasma oxidation technology (PEO) places the metal workpiece to be processed in a specific electrolyte, and by applying a high voltage, a plasma discharge phenomenon is generated in the micro-area of ​​the metal surface, forming a tiny arc channel. In this process, metal atoms lose electrons under the action of a high electric field and become metal ions that enter the electrolyte. At the same time, oxygen ions in the electrolyte also undergo complex chemical reactions with the metal ions, and finally form an oxide film with ceramic properties on the metal surface. The present invention aims to solve the problem that the service life of a water diaphragm pump is shortened due to wear and corrosion of the inner wall of the pipeline. To solve this problem, the present invention prolongs the service life of the water diaphragm pump, including the following steps: 1. Perform workpiece surface treatment on the inner wall material of the water diaphragm pump pipeline. Step 2. Perform workpiece size measurement and processing on the inner wall material of the water diaphragm pump pipeline. Step 3. Mark the workpiece number on the inner wall material of the water diaphragm pump pipeline. Step 4. Perform plasma electrolytic oxidation (PEO) on the inner wall material of the water diaphragm pump pipeline. Step 5. Observe and analyze the workpiece after PEO treatment. Step 6. Package and store the inner wall material of the water diaphragm pump pipe after plasma electrolytic oxidation (PEO) and wait for subsequent processing steps. Step 1 is to remove stains on the surface of the material to ensure the cleanliness of the workpiece. Step 2 is to facilitate the subsequent welding processing of the workpiece. Step 3 is to facilitate the management of the workpiece by the enterprise factory. Step 4 is the core technology, which can greatly improve the wear resistance and corrosion resistance of the inner wall material of the water diaphragm pump. Step 5 is a necessary step to test whether the invented method can improve the wear resistance and corrosion resistance, thereby extending the service life of the water diaphragm pump. Step 6 is to keep the workpiece in good condition to facilitate the subsequent processing process. BRIEF DESCRIPTION OF THE DRAWINGS

[0005] Figure 1 The PEO coating grown on the titanium alloy after the PEO treatment in the embodiment; Figure 2 It is a mechanism diagram of PEO treatment in the embodiment; Figure 3 The present invention is to analyze the composition of the titanium alloy film layer after PEO treatment; Figure 4 is a cross-sectional image of the PEO coating after PEO treatment in Example; Figure 5 This is the EIS image (reactive corrosion resistance) after PEO treatment in the example. DETAILED DESCRIPTION

[0006] The following implementation method describes the embodiment of the present invention in detail. It is exemplary and not restrictive. In the embodiment of the present invention, the present invention provides a method for extending the service life of a water diaphragm pump. Step 1. (1) After wiping or soaking the titanium alloy with an organic solvent (such as acetone solution) for 15 minutes, wipe it with a clean cotton cloth to remove surface oil. If the carbon steel surface is seriously contaminated, soak it for 30 minutes. (2) Use compressed air blowing, water rinsing, etc. to remove impurities on the surface of the titanium alloy to ensure that the surface of the workpiece is clean. Step 2. (1) Place the workpiece between the anvil and the micrometer screw of the micrometer, gently rotate the differential cylinder, and slowly approach the workpiece until the measuring surface of the micrometer screw gently contacts the surface of the workpiece, and read the size value on the micrometer (size of 20×20×2 mm³); (2) Use an electric spark CNC wire cutting machine to process the titanium alloy according to the size value (size of 20×20×2 mm³). Step 3. Number the cut titanium alloy workpiece. Start from 1 and increase from small to large. Step 4. Use a bench-top multi-function drill press to drill holes above the substrate surface with a drill bit diameter of 5 mm and connect to the sample using aluminum wire. Before plasma electrolytic oxidation (PEO) treatment, the workpiece needs to be sanded with #400 to #1500 sandpaper, polished, cleaned with deionized water, cleaned with anhydrous ethanol, and dried with hot air. The pulse power supply (DSM30H) uses a constant voltage mode with a positive voltage of 340V, a negative voltage of 60V, a duty cycle of 30%, and a reaction time of 10 minutes. PEO treatment was carried out in a silicate electrolyte system consisting of Na2SiO3 (10 g / L), KOH (1 g / L), and K2ZrF6 (0, 2, 4, 6, and 8 g / L). The pH values ​​of the electrolytes with different K2ZrF6 contents were measured by a pH meter (PB-10, Sartorius, Germany), which were 12.59, 12.60, 12.61, 12.62 and 12.62, respectively. The electrolyte was kept at 10-15°C by a cooling water bath stirring device to ensure that the PEO reaction proceeded normally. Step 5. 5.1 (1) The surface and cross-sectional morphology of the coating were observed by scanning electron microscopy (SEM, S4800, Hitachi). (2) Hardness measurement was performed on the surface of the PEO coating by a digital microhardness tester (HXD-1000TMB). (3) The phase structure of the ceramic coating was detected using an X-ray diffractometer (D / max-2500PC, Rigaku). These operations can accurately reflect the wear resistance of the material. 5.2 (1) The porosity and pore size were determined using ImageJ, and 3 measurements were performed. This operation can accurately reflect the corrosion resistance of the material. Step 6. (1) Thoroughly clean the PEO-treated workpiece (using clean water and detergent). (2) Dry it thoroughly in an oven at 60°C.(3) Add cushioning materials such as foam and sponge to the wooden box and use the wooden box to pack the workpiece. Results Analysis

[0007] After the operation of step 5. (1) It was found that the hardness of TC4 titanium alloy without PEO treatment was about 332.8HV. After PEO treatment, the hardness of the coating reached 488.4HV. In addition, the addition of K2ZrF6 increased the electric field strength of the system and intensified the reaction intensity. Under the action of the strong electric field force, anions such as ZrF6²⁻, SiO3²⁻, and OH⁻ quickly migrated to the anode surface, and more molten oxides were deposited on the substrate surface after cooling and solidification, which promoted the increase of film thickness. The above phenomenon shows that PEO treatment can greatly improve the hardness and thickness of the coating surface. Therefore, it can be seen that PEO treatment greatly increases the wear resistance of the material. (2) It was found that the composite ceramic coating showed a layered structure. There are multiple micropores in the external pores, which is conducive to inhibiting the contact between the corrosive medium and the substrate, thereby enhancing the protection of the substrate. The fitting results of EIS show that compared with TC4, the sample treated with PEO has a lower Y value, which means that PEO treatment can improve the corrosion resistance of the substrate.

[0008] The present invention provides a method for extending the service life of a water diaphragm pump. By treating the inner wall material of the water diaphragm pump pipeline with PEO, the wear resistance and corrosion resistance thereof are greatly improved, friction loss is reduced, the integrity of the pipeline structure is protected, and the medium conveying performance is maintained stable. This plays a vital role in extending the service life of the water diaphragm pump and its pipeline.

Claims

1. A method for extending the service life of a water diaphragm pump, characterized in that: Specifically, the following steps are included: step 1. performing workpiece surface treatment on the inner wall material of the water diaphragm pump pipe; step 2. performing workpiece size measurement and processing on the inner wall material of the water diaphragm pump pipe; step 3. marking the workpiece number on the inner wall material of the water diaphragm pump pipe; step 4. performing plasma electrolytic oxidation (PEO) on the inner wall material of the water diaphragm pump pipe; step 5. observing and analyzing the workpiece after PEO treatment; step 6. packaging and storing the inner wall material of the water diaphragm pump pipe after plasma electrolytic oxidation (PEO), waiting for subsequent processing steps.

2. A method for extending the service life of a water diaphragm pump according to claim 1, step 1: (1) performing workpiece surface treatment on the inner wall material of the water diaphragm pump pipeline, characterized in that Use an organic solvent (such as acetone solution) to wipe or soak the titanium alloy for 15 minutes, then wipe it with a clean cotton cloth to remove surface oil stains. If the titanium alloy surface is severely contaminated, soak it for 30 minutes. (2) Use compressed air blowing, water rinsing, etc. to remove impurities on the carbon steel surface to ensure the cleanliness of the workpiece surface.

3. A method for extending the service life of a water diaphragm pump according to claim 1, step 2: (1) measuring the workpiece size of the inner wall material of the water diaphragm pump pipeline and, characterized in that, Place the workpiece between the anvil and the micrometer screw of the micrometer, gently rotate the differential cylinder, and slowly move the micrometer screw closer to the workpiece until the measuring surface of the micrometer screw lightly contacts the workpiece surface, and read the size value on the micrometer (size of 20×20×2 mm³); (2) Use an EDM CNC wire cutting machine to process the titanium alloy substrate.

4. A method for extending the service life of a water diaphragm pump according to claim 1, step 3: marking the inner wall material of the water diaphragm pump pipeline with a workpiece number, characterized in that: The cut titanium alloy workpieces are numbered, starting from 1 and increasing from small to large.

5. A method for extending the service life of a water diaphragm pump according to claim 1, step 4: performing plasma electrolytic oxidation (PEO) on the inner wall material of the water diaphragm pump pipeline, characterized in that: The workpiece needs to be sanded with #400 to #1500 sandpaper, polished, cleaned with deionized water, cleaned with anhydrous ethanol and dried with hot air. The pulse power supply (DSM30H) adopts constant voltage mode, with a positive voltage of 340V, a negative voltage of 60V, a duty cycle of 30%, and a response time of 10 minutes.

6. According to the method for extending the service life of a water diaphragm pump as described in claim 1, step 5 needs to be performed. Some low-melting-point metals, such as tin, lead, etc., and some metals with high activity and easy oxidation, such as lithium, sodium, etc., are not suitable for plasma electrolytic oxidation (PEO). Therefore, step 5 needs to be performed. Refer to the embodiment pictures to determine whether it is suitable.

7. According to the method for extending the service life of a water diaphragm pump as claimed in claim 1, step 6: packaging and storing the inner wall material of the water diaphragm pump pipe after plasma electrolytic oxidation (PEO), characterized in that: Wash the PEO-treated workpiece thoroughly (with clean water and detergent), dry it fully, dry it in an oven at 60°, add foam, sponge and other cushioning materials to the wooden box, and pack the workpiece in the wooden box to maintain the good performance of the material to the greatest extent.

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