Switchable mechanical pump air-exhausting device for vacuum refining of molten steel

Abstract

The invention provides a switchable mechanical pump air-exhausting device for vacuum refining of molten steel and belongs to the technical field of external refining of steel-making furnaces. The switchable mechanical pump air-exhausting device comprises a water-cooled air exhausting pipe (1), an air cooler (2), an air exhausting pipe (3), a vacuum fast switching box (4), a high-temperature dust filter (5), a front pump valve (6), a lobe pump unit (7), a rear pump valve (8), a switching valve (9), a screw pump unit (10), a water ring pump unit (11) and an emptying pipeline (12). According to the switchable mechanical pump air-exhausting device, four different combination modes can be achieved through the vacuum fast switching box (4) and the switching valve (9) so as to adapt to different working conditions in the vacuum treatment process. The switchable mechanical pump air-exhausting device for vacuum refining of molten steel has the advantages that the air exhausting efficiency of a mechanical pump is high, the service life of equipment is long, and the operating cost is low.

Description

technical field [0001] The invention belongs to the technical field of refining outside a steelmaking furnace, and in particular relates to a switchable mechanical pump exhaust device for vacuum refining of molten steel, which is suitable for the vacuum refining process of molten steel in steelmaking, including RH, VD, VCD, VOD, VC vacuum treatment and the like. Background technique [0002] At present, the refining technology outside the steelmaking furnace is widely used, especially the vacuum refining of molten steel is getting more and more attention from steel mills to improve the cleanliness of products. The molten steel vacuum refining process mainly has different forms such as RH, VD, VCD, VOD, VC, etc., and their common feature is that they all need a vacuum system, which is used to keep the sealed molten steel environment below atmospheric pressure (negative pressure). Under different negative pressure environments, different forms of vacuum treatment processes ach...

AI Technical Summary

Problems solved by technology

However, the traditionally used primary Roots pump + secondary Roots pump + three-stage screw pump has the following problems: 1. Due to the high temperature and dust content of the exhaust gas extracted during the vacuum treatment process, there are Roots pumps and screw pumps. The efficiency of the pump is reduced after heat generation and dust wear on the pump body; 2. Even as described in the patent CN204401047U: the primary Roots pump + secondary Roots pump + three-stage water ring pump system still has long pre-pumping time and high power consumption

The above-mentioned first-stage Roots pump + second-stage Roots pump + third-stage screw pump or first-stage Roots pump + second-stage Roots pump + third-stage water ring pump cannot all adapt to these working conditions

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