Centrifugal pump

Description

[0001] Technical field

[0002] The utility model relates to pump engineering, in particular to a centrifugal pump, which is designed for pumping fluids, in particular oil, water, water-oil mixture, water-gas-oil mixture in oil and gas wells, in oilfield transport systems and installations for oil and gas preparation.

[0003] Technology Level

[0004] A device for hydrophobicizing the flow paths of dynamic pumps is known from the prior art. This technical solution is aimed at increasing pump efficiency by applying a hydrophobic coating to the pump's flow paths (RU 51619).

[0005] A technical solution is known from the prior art, adopted as the closest analogue, a centrifugal pump, in which the inner surface of the housing, the surfaces of the guide vanes and impellers are coated with a polymer hydrophobic composition (RU 52128).

[0006] As is well known, during operation, pump wet-end components, even those made of high-alloy steel with a corrosion-resistant coating, are exposed to aggressive environments. As a result, such surfaces may become highly rough, and pitting and microcracks may develop, which can degrade the quality of the coating applied to the pump wet-end components. Also, exposure to high temperatures, for example, above 50°C, increases the likelihood of defects during coating application.

[0007] A common technical problem with known solutions is that the surface quality of the flow path elements is insufficient for the efficient operation of the pump. During operation, the surfaces become highly rough, which creates additional friction and turbulence, as a result of which the required efficiency of liquid pumping and protection of the pump elements from erosion and corrosion are not ensured, which in turn leads to a decrease in the reliability and efficiency of the centrifugal pump.

[0008] The technical result is to increase the reliability of the centrifugal pump.

[0009] The technical result is achieved by a centrifugal pump comprising a casing with suction and pressure chambers, a diffuser chamber with an impeller and auger located within the casing. A corrosion-resistant, hydrophobic, and wear-resistant coating is applied to the inner surfaces of the casing, as well as to the outer surfaces of the impeller and auger. This problem is solved, and the technical result is achieved, by applying a wear-resistant coating to the surfaces of the suction and pressure chambers, the outer surface of the auger, the impeller, and the diffuser chamber, which are resistant to temperatures in the range from 10°C to 50°C. The wear-resistant coating is a two-component coating containing epoxy resin and a hardener, with the thickness of the wear-resistant coating ranging from 0.4 to 0.5 mm.

[0010] Content of epoxy resin and hardener 1:1.

[0011] Brief description of drawings

[0012] The utility model is illustrated:

[0013] The figure shows a longitudinal section of a centrifugal pump with a coating applied,

[0014] where 1 - housing; 2 - impeller; 3 - shaft; 4 - suction chamber; 5 - pressure chamber; 6 - screw; 7 - diffuser chamber; 8 - multiplier.

[0015] Implementation of a utility model

[0016] The centrifugal pump comprises a casing 1, which ensures sealing and directs fluid flow. Within casing 1 is an impeller 2, mounted on a shaft 3, which is secured within casing 1 for rotation. The inner surface of casing 1 is coated with a wear-resistant coating. The pump casing contains a discharge and suction chamber. The discharge chamber converts dynamic pressure into pressure. The suction chamber supplies fluid from the suction line directly to the inlet edges of the impeller blades.

[0017] The surface of the pressure chamber 5 is located between the impeller 2 and the casing. The surface of the suction chamber is located on the end side of the pump casing. The surfaces of the suction 4 and pressure 5 chambers, the outer surface of the screw 6, the impeller 2, and the diffuser chamber 7 are made with a wear-resistant coating resistant to temperatures in the range from 10 to 50°C. The screw is installed behind the suction chamber on the shaft in front of the impeller. The screw 6 is a screw shaft with blades that mix the liquid, creating pressure and flow. To increase the rotation speed of the impeller 2, a multiplier 8 is used, which is mounted on shaft 3 and, when rotating, creates centrifugal force to move the liquid into the diffuser chamber 7 for an even distribution of the liquid flow.

[0018] Belzona 1341, a two-component coating consisting of an epoxy resin and hardener, was used as a wear-resistant coating. This coating is a two-component metal-polymer based on epoxy resin, designed to create a hydrophobic coating to protect metal surfaces from corrosion and erosion. A component of cold-curing composite materials is used as a hardener. A 1:1 ratio of epoxy resin to hardener ensures the most effective result; improper use will degrade the coating's quality.

[0019] Before applying the wear-resistant coating, the surfaces are pre-cleaned to remove dirt, rust, grease, old paint, and other contaminants. For better adhesion, the surfaces should be slightly roughened. Then, the surfaces are degreased, dried, and the wear-resistant coating is applied.

[0020] Applying a wear-resistant coating helps protect centrifugal pump components from corrosion, which is especially important when operating in aggressive environments.

[0021] The thickness of the wear-resistant coating is preferably 0.4 to 0.5 mm.

[0022] Applying a layer thickness of less than 0.4 mm reduces the wear resistance of the material due to insufficient coating thickness, which may lead to coating peeling and reduce pump efficiency. Applying a coating thickness of more than 0.5 mm may increase the risk of dripping due to excessive layer thickness, which will increase the curing time of the coating, which will also negatively impact surface quality.

[0023] The optimal thickness of the wear-resistant coating is from 0.4 to 0.5 mm:

[0024] The first layer is applied evenly, avoiding gaps;

[0025] The second layer is applied after the first layer has been cured for 4-6 hours at 20°C, but not later than 24 hours to avoid oxidation.

[0026] By mixing the base and solid components (epoxy resin and hardener) and then spraying them onto the surfaces of the suction and discharge chambers, the outer surface of the screw, the impeller, the diffuser chamber, and the inner surface of the housing, smooth and even surfaces with low roughness are achieved. Application of the coating at temperatures below 10°C will result in a disruption of the coating's adhesion, leading to peeling of the applied layer from the surface, uneven curing, and a deterioration in its protective properties. At temperatures above 50°C, the coating will be ineffective, as peeling, cracking, and chipping are possible. This will result in the protective layer losing its effectiveness and the base metal will be subject to intense wear.

[0027] Thus, the proposed solution makes it possible to create a centrifugal pump with a wear-resistant coating on the surface of the suction and pressure chambers, the outer surface of the screw, and the diffuser chamber, resistant to temperatures in the range from 10 to 50°C, which helps to increase the reliability of the centrifugal pump and wear resistance due to the application of a wear-resistant coating.

Claims

1. A centrifugal pump comprising a housing with suction and pressure chambers, a diffuser chamber with an impeller and auger located inside the housing, wherein the inner surface of the housing is made with a coating, characterized in that the surfaces of the suction and pressure chambers, the outer surface of the impeller and auger, and the diffuser chamber are made with the application of a corrosion-resistant, hydrophobic, wear-resistant coating that is resistant to temperatures in the range from 10 to 50°C, wherein a two-component coating containing epoxy resin and a hardener is used as the wear-resistant coating, wherein the thickness of the wear-resistant coating is from 0.4 mm to 0.5 mm.

2. A centrifugal pump according to paragraph 1, characterized in that the content of epoxy resin and hardener is 1:1.

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