Corrosion-resistant dry-grinding-resistant centrifugal pump

Abstract

The invention discloses a corrosion-resistant dry-grinding-resistant centrifugal pump, which comprises a pump shell, a main shaft, a shaft seal on the main shaft, a bearing seat and an impeller installed at the end of the main shaft and located in a pump shell volute cavity. The shaft seal comprises a sealing box assembly and a mechanical seal. The mechanical seal comprises a static ring and a movable ring; the sealing box assembly is fixedly connected with the pump shell; the movable ring is fixed on the main shaft; the movable ring is positioned in the pump cavity and is in contact with conveyed feed liquid; the sealing box assembly comprises a sealing box, a sealing box pressing rear cover which is separated from or integrated with the sealing box, and a static ring pushing elastic circle arranged in the sealing box; two ends of the static ring pushing elastic circle are compressed between the sealing box pressing rear cover and the static ring; the static ring pushing elastic circle is in an elastic compression state, a static ring friction amplitude and a movable ring friction amplitude are contacted and sealed, a rigid partition plate is fixedly connected to the sealing end face of the sealing box and the sealing end face of the pump shell, the circumferential face of an inner hole of the rigid partition plate makes contact with the outer circumferential face of the static ring in a sealed mode, and the outer circumferential face of the static ring pushing elastic circle, the sealing box pressing rear cover, the rigid partition plate and the static ring form a liquidstorage cavity in a surrounding mode.

Description

technical field [0001] The invention relates to the field of anticorrosion centrifugal pump manufacture, in particular to a centrifugal pump for conveying corrosive slurry containing chlorine ion components and the like. Background technique [0002] Centrifugal pumps are used to transport the clear liquid or slurry containing chloride ions in the flue gas desulfurization process of iron and steel enterprises and coal chemical enterprises, and in the nickel-cobalt hydrometallurgy process. However, this type of medium is very corrosive to metals, especially the pump shaft seal, which requires metal components such as metal springs, bolts and nuts, and these components are easily corroded by the transported chlorine-containing ionic liquid or corrosive gas. It is therefore thought of developing a centrifugal pump with a pump shaft seal in which the liquid does not come into contact with the metal components. [0003] Some people use a lip-shaped rubber seal with a dynamic sea...

AI Technical Summary

Problems solved by technology

This kind of pump shaft seal has excellent anti-corrosion performance, and all mechanical seal components will not be corroded by the conveying medium, but there are the following disadvantages: First, the conveying medium in the pump chamber is in contact with the rubber push ring, and the rubber push ring is immersed In the conveyed medium, the acidity or alkalinity in the conveying medium will produce a reduction reaction of the vulcanizing agent on the rubber push ring, which will soften the rubber push ring and lose its elasticity, thereby causing the seal to fail

The third is that the machine seal cannot be equipped with external cooling water, so as long as the pump loses fluid and runs, the machine seal will be burned by dry grinding

Through innovation and improvement, the rubber push ring in the original technology has no contact with the conveying liquid in the pump chamber, and the push ring will not be deformed by the acid and alkali medium in the pump chamber, and the seal can also run empty , has good anti-dry wear performance, but there are still the following problems that are difficult to solve: First, because the cavity between the pump chamber and the sealing box is separated by a flexible partition with a "U"-shaped ring groove, the flexible partition Due to the pressure change of the fluid in the pump chamber, the plate body will be tightened and compressed or pushed away. The dynamic and static rings are disengaged, causing the delivery liquid in the pump cavity to leak into the cooling water cavity, making the pump seal invalid

The second is that the shaft seal 5 that seals the cooling water has a short service life, generally only 3 to 4 months, and there is still a hidden danger of cooling water leakage

The third is that each pump consumes 2~3 tons of cooling water per day, which is very considerable

[0006] Therefore, the mechanical seal of the centrifugal pump with good anti-corrosion performance and the fluid does not contact the metal components of the sealing part in the original technology still has the shortcomings of unstable performance and leakage of cooling water, and there is still a need for improvement.

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