CN114182064A

CN114182064A - Mechanical vacuum pump system and control method thereof

Info

Publication number: CN114182064A
Application number: CN202111318022.9A
Authority: CN
Inventors: 严淑; 许海虹; 欧洪林
Original assignee: Wisdri Engineering and Research Incorporation Ltd
Current assignee: Wisdri Engineering and Research Incorporation Ltd
Priority date: 2021-11-08
Filing date: 2021-11-08
Publication date: 2022-03-15
Anticipated expiration: 2041-11-08
Also published as: CN114182064B

Abstract

The invention discloses a mechanical vacuum pump system and a control method thereof, belonging to the technical field of steel-making vacuum refining in the metallurgical industry, and comprising a first RH vacuum refining furnace, a second RH vacuum refining furnace, a vacuum pump mechanism and a valve mechanism, wherein the vacuum pump mechanism comprises a first pump, a second pump, a first set of third pump, a first set of fourth pump, a second set of third pump and a second set of fourth pump, and the first pump is respectively connected with the first RH vacuum refining furnace and the second RH vacuum refining furnace; the second-stage pump is connected with the first-stage pump; the first set of third-stage pump is connected with the second-stage pump; the first set of fourth-stage pump is respectively connected with the first set of third-stage pump, the second-stage pump and the first RH vacuum refining furnace; the second set of third-stage pump is connected with the second-stage pump; the second set of fourth-stage pump is respectively connected with the second set of third-stage pump, the second-stage pump and the second RH vacuum refining furnace. The invention achieves the technical effects of simplifying the structure and reducing the construction cost and the production cost.

Description

Mechanical vacuum pump system and control method thereof

Technical Field

The invention belongs to the technical field of steel-making vacuum refining in the metallurgical industry, and particularly relates to a mechanical vacuum pump system and a control method thereof.

Background

With the continuous expansion of the demand of users for steel products and the increasing demand for steel product quality, the RH vacuum treatment technology has become one of the effective means for expanding the product range and improving the product quality. The vacuum pump is a core component of the RH vacuum refining furnace, and the number of RH vacuum refining devices adopting the full-dry type mechanical vacuum pump is rapidly increasing due to excellent low operation cost, energy-saving and environment-friendly effects.

At present, in the vacuum refining technology of steel making in the existing metallurgical industry, a steam jet pump is generally adopted, or an electric arc furnace is taken as an indispensable scrap steel or reduced iron melting means of a modern short-flow steel plant, and 1: the RH vacuum finers associated with 1 have been increasingly unable to meet the requirements of the electric arc furnace for shorter tapping cycles, which would result in higher construction costs if one were to increase the number of RH vacuum finers associated with the electric arc furnace. Like this because the RH vacuum refining device quantity that adopts full dry-type mechanical vacuum pump is in rapid growth, the supporting vacuum pump system of every RH vacuum refining stove of current adoption for the supporting vacuum pump system quantity is more, and the structure is more complicated, can lead to the construction cost higher and manufacturing cost higher.

In conclusion, the prior steel-making vacuum refining technology in the metallurgical industry has the technical problems of complex structure, high construction cost and high production cost.

Disclosure of Invention

The invention aims to solve the technical problems of complex structure, high construction cost and high production cost.

To solve the above technical problem, the present invention provides a mechanical vacuum pump system, comprising: a first RH vacuum refining furnace and a second RH vacuum refining furnace; the vacuum pump mechanism comprises a first-stage pump, a second-stage pump, a first set of third-stage pump, a first set of fourth-stage pump, a second set of third-stage pump and a second set of fourth-stage pump, and the first-stage pump is respectively connected with a first RH vacuum refining furnace and a second RH vacuum refining furnace; the second-stage pump is connected with the first-stage pump; the first set of third-stage pump is connected with the second-stage pump; the first set of fourth-stage pump is respectively connected with the first set of third-stage pump, the second-stage pump and the first RH vacuum refining furnace; the second set of third stage pump is connected with the second stage pump; the second set of fourth-stage pump is respectively connected with the second set of third-stage pump, the second-stage pump and the second RH vacuum refining furnace; the valve mechanism comprises a first control valve, a second control valve, a third control valve, a fourth control valve, a fifth control valve, a sixth control valve, a seventh control valve, an eighth control valve, a ninth control valve and a tenth control valve, the first control valve is installed between a first RH vacuum refining furnace and a first-stage pump, and the second control valve is installed between the first control valve and the first-stage pump; the third control valve is arranged between the second-stage pump and the first set of third-stage pumps; the fourth control valve is arranged between the first set of fourth-stage pump and the second set of fourth-stage pump; the fifth control valve is arranged between the fourth control valve and the first control valve; the sixth control valve is arranged between the second RH vacuum refining furnace and the first-stage pump, and the seventh control valve is arranged between the sixth control valve and the first-stage pump; the eighth control valve is arranged between the second-stage pump and the second set of third-stage pump; the ninth control valve is arranged between the eighth control valve and the second set of fourth-stage pumps; the tenth control valve is installed between the ninth control valve and the sixth control valve.

Further, the first-stage pump comprises a plurality of roots vacuum pumps; the second-stage pump comprises a plurality of roots vacuum pumps; the first set of third-stage pumps comprises a plurality of roots vacuum pumps; the first set of fourth stage pumps comprises a plurality of screw vacuum pumps.

Further, the second set of third stage pumps comprises a plurality of roots vacuum pumps; the second set of fourth stage pumps comprises a plurality of screw vacuum pumps.

Further, the first control valve is a switching valve, the second control valve is a switching valve, the third control valve is a switching valve, the fourth control valve is a switching valve, the fifth control valve is a switching valve, the sixth control valve is a switching valve, the seventh control valve is a switching valve, the eighth control valve is a switching valve, the ninth control valve is a switching valve, and the tenth control valve is a switching valve.

Further, the first RH vacuum refining furnace is capable of processing a first target molten steel, the first target molten steel comprises a light processing steel grade, a present processing steel grade or a deep decarburization steel grade; the second RH vacuum refining furnace is configured to process a second target molten steel, which includes a light-treated steel grade, a present-treated steel grade, or a deep decarburized steel grade.

According to yet another aspect of the present invention, there is also provided a method of controlling a mechanical vacuum pump system, the method comprising: step S1, when the first RH vacuum refining furnace is in the end of the deep vacuum state and the second RH vacuum refining furnace is in the pre-pumping state, opening the first control valve, the second control valve, the third control valve, the ninth control valve and the tenth control valve, closing the fourth control valve, the fifth control valve, the sixth control valve, the seventh control valve and the eighth control valve, opening the first pump, the second pump, the first set of third pumps, the first set of fourth pumps and the second set of fourth pumps, and closing the second set of third pumps; step S2, when the first RH vacuum refining furnace is in the end of the deep vacuum state and the second RH vacuum refining furnace is in the rough vacuum state, opening the first control valve, the second control valve, the third control valve, the sixth control valve and the tenth control valve, closing the fourth control valve, the fifth control valve, the seventh control valve, the eighth control valve and the ninth control valve, and opening the first pump, the second pump, the first set of third pumps, the first set of fourth pumps, the second set of third pumps and the second set of fourth pumps; step S3, when the first RH vacuum refining furnace is in a pre-pumping state and the second RH vacuum refining furnace is in a deep vacuum state, opening a fourth control valve, a fifth control valve, a sixth control valve, a seventh control valve and an eighth control valve, closing the first control valve, the second control valve, the third control valve, the ninth control valve and the tenth control valve, opening a first pump, a second pump, a first set of fourth-stage pumps, a second set of third-stage pumps and a second set of fourth-stage pumps, and closing the first set of third-stage pumps; circularly executing the step S1, the step S2 and the step S3.

Has the advantages that:

the invention provides a mechanical vacuum pump system, wherein a first pump in the vacuum pump mechanism is respectively connected with a first RH vacuum refining furnace and a second RH vacuum refining furnace, a second pump is connected with the first pump, a first set of third pump is connected with the second pump, a first set of fourth pump is respectively connected with a first set of third pump, a second pump and the first RH vacuum refining furnace, a second set of third pump is connected with the second pump, a second set of fourth pump is respectively connected with the second set of third pump, the second pump and the second RH vacuum refining furnace, a first control valve in the valve mechanism is arranged between the first RH vacuum refining furnace and the first pump, a second control valve is arranged between the first control valve and the first pump, a third control valve is arranged between the second pump and the first set of third pump, a fourth control valve is arranged between the first set of fourth pump and the second pump, the fifth control valve is arranged between the fourth control valve and the first control valve, the sixth control valve is arranged between the second RH vacuum refining furnace and the first-stage pump, the seventh control valve is arranged between the sixth control valve and the first-stage pump, the eighth control valve is arranged between the second-stage pump and the second set of third-stage pump, the ninth control valve is arranged between the eighth control valve and the second set of fourth-stage pump, and the tenth control valve is arranged between the ninth control valve and the sixth control valve. Like this first-order pump and second level pump are connected with first RH vacuum refining stove, and first-order pump and second level pump also are connected with second RH vacuum refining stove, realize first-order pump in first RH vacuum refining stove and the sharing vacuum pump mechanism of second RH vacuum refining stove, and second level pump in first RH vacuum refining stove and the sharing vacuum pump mechanism of second RH vacuum refining stove, can simplify the structure, reduce construction cost and manufacturing cost, thereby reached and simplified the structure, reduce construction cost and manufacturing cost's technological effect.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.

FIG. 1 is a first schematic diagram of a mechanical vacuum pump system according to an embodiment of the present invention;

FIG. 2 is a second schematic diagram of a mechanical vacuum pump system according to an embodiment of the present invention;

FIG. 3 is a third schematic diagram of a mechanical vacuum pump system according to an embodiment of the present invention;

fig. 4 is a flowchart illustrating a method for controlling a mechanical vacuum pump system according to an embodiment of the present invention.

Detailed Description

The invention discloses a mechanical vacuum pump system, wherein a first-stage pump 31 in a vacuum pump mechanism is respectively connected with a first RH vacuum refining furnace 1 and a second RH vacuum refining furnace 2, a second-stage pump 32 is connected with the first-stage pump 31, a first set of third-stage pump 33 is connected with the second-stage pump 32, a first set of fourth-stage pump 34 is respectively connected with the first set of third-stage pump 33, the second-stage pump 32 and the first RH vacuum refining furnace 1, a second set of third-stage pump 35 is connected with the second-stage pump 32, a second set of fourth-stage pump 36 is respectively connected with the second set of third-stage pump 35, the second-stage pump 32 and the second RH vacuum refining furnace 2, a first control valve 41 in a valve mechanism is arranged between the first RH vacuum refining furnace 1 and the first-stage pump 31, a second control valve 42 is arranged between the first control valve 41 and the first-stage pump 31, a third control valve 43 is arranged between the second-stage pump 32 and the first set of third-stage pump 33, the fourth control valve 44 is installed between the first set of the fourth stage pump 34 and the second stage pump 32, the fifth control valve 45 is installed between the fourth control valve 44 and the first control valve 41, the sixth control valve 46 is installed between the second RH vacuum refining furnace 2 and the first stage pump 31, the seventh control valve 47 is installed between the sixth control valve 46 and the first stage pump 31, the eighth control valve 48 is installed between the second stage pump 32 and the second set of the third stage pump 35, the ninth control valve 49 is installed between the eighth control valve 48 and the second set of the fourth stage pump 36, and the tenth control valve 50 is installed between the ninth control valve 49 and the sixth control valve 46. Like this first order pump 31 and second level pump 32 are connected with first RH vacuum refining furnace 1, and first order pump 31 and second level pump 32 also are connected with second RH vacuum refining furnace 2, realize first order pump 31 in the vacuum pump mechanism is shared to first RH vacuum refining furnace 1 and second RH vacuum refining furnace 2, and second level pump 32 in the vacuum pump mechanism is shared to first RH vacuum refining furnace 1 and second RH vacuum refining furnace 2, can simplify the structure, reduce construction cost and manufacturing cost, thereby reached and simplified the structure, reduce construction cost and manufacturing cost's technological effect.

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments of the present invention belong to the protection scope of the present invention; the "and/or" keyword referred to in this embodiment represents sum or two cases, in other words, a and/or B mentioned in the embodiment of the present invention represents two cases of a and B, A or B, and describes three states where a and B exist, such as a and/or B, which represents: only A does not include B; only B does not include A; including A and B.

It will be understood that, although the terms first, second, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or section from another element, component, region, layer or section. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the example embodiments. Spatially relative terms, such as "below," "above," and the like, may be used herein to facilitate describing one element or feature's relationship to another element or feature. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements or features described as "lower" would then be oriented "upper" other elements or features. Thus, the exemplary term "below" can encompass both an orientation of above and below. The device may be oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

Also, in embodiments of the invention where an element is referred to as being "secured to" another element, it can be directly on the other element or intervening elements may also be present. When a component is referred to as being "connected" to another component, it can be directly connected to the other component or intervening components may also be present. When a component is referred to as being "disposed on" another component, it can be directly on the other component or intervening components may also be present. The terms "vertical," "horizontal," "left," "right," and the like as used in the embodiments of the present invention are for illustrative purposes only and are not intended to limit the present invention.

Example one

Referring to fig. 1, fig. 2 and fig. 3, fig. 1 is a first schematic diagram of a mechanical vacuum pump system according to an embodiment of the present invention, fig. 2 is a second schematic diagram of the mechanical vacuum pump system according to the embodiment of the present invention, and fig. 3 is a third schematic diagram of the mechanical vacuum pump system according to the embodiment of the present invention. The mechanical vacuum pump system provided by the embodiment of the invention comprises a first RH vacuum refining furnace 1, a second RH vacuum refining furnace 2, a vacuum pump mechanism and a valve mechanism, wherein the first RH vacuum refining furnace 1, the second RH vacuum refining furnace 2, the vacuum pump mechanism and the valve mechanism are respectively explained in detail:

for the first RH vacuum refining furnace 1:

the first RH vacuum refining furnace 1 is provided for processing a first target molten steel including a light-treated steel grade, a present-treated steel grade, or a deep decarburized steel grade; the second RH vacuum refining furnace 2 is provided for processing a second target molten steel including a light-treated steel grade, a present-treated steel grade, or a deep decarburized steel grade.

Specifically, the first RH vacuum refining furnace 1 is an RH vacuum refining furnace, that is, an RH vacuum circulation degassing refining furnace, and the first RH vacuum refining furnace 1 can be used for the treatment of a light-treated steel type, a present-treated steel type, or a deep decarburization steel type. The second RH vacuum refining furnace 2 is another RH vacuum refining furnace, and the second RH vacuum refining furnace 2 can be used for the treatment of the light treated steel grade, the present treated steel grade, or the deep decarburized steel grade.

For the vacuum pump mechanism:

the vacuum pump mechanism comprises a first-stage pump 31, a second-stage pump 32, a first set of third-stage pump 33, a first set of fourth-stage pump 34, a second set of third-stage pump 35 and a second set of fourth-stage pump 36, wherein the first-stage pump 31 is respectively connected with the first RH vacuum refining furnace 1 and the second RH vacuum refining furnace 2; the second-stage pump 32 is connected with the first-stage pump 31; the first set of third stage pumps 33 is connected with the second stage pump 32; the first set of fourth-stage pump 34 is respectively connected with the first set of third-stage pump 33, the second-stage pump 32 and the first RH vacuum refining furnace 1; the second set of third stage pumps 35 is connected with the second stage pump 32; the second set of fourth stage pump 36 is connected with the second set of third stage pump 35, the second stage pump 32 and the second RH vacuum refining furnace 2 respectively. Wherein the first-stage pump 31 comprises a plurality of roots vacuum pumps; the second-stage pump 32 comprises a plurality of roots vacuum pumps; the first set of third stage pumps 33 comprises a plurality of roots vacuum pumps; the first set of fourth stage pumps 34 comprises a plurality of screw vacuum pumps. The second set of third stage pumps 35 comprises a plurality of roots vacuum pumps; the second set of fourth stage pumps 36 comprises a plurality of screw vacuum pumps.

Specifically, the roots vacuum pump may be a variable displacement vacuum pump in which two vane-shaped rotors rotating synchronously in opposite directions are installed, and small gaps are formed between the rotors and the inner wall of the pump housing so as not to contact each other. The screw vacuum pump is an air-extracting device that performs suction and exhaust actions by a pair of screws rotating in a pump casing in a synchronized high-speed reverse direction. The first pump 31 is a vacuum chamber side, the first set of fourth pump 34 and the second set of fourth pump 36 can be exhaust sides, the first pump 31 is respectively connected with the first RH vacuum refining furnace 1 and the second RH vacuum refining furnace 2 through pipelines, the first pump 31 comprises a plurality of roots vacuum pumps, the first pump 31 comprises A roots vacuum pumps, and A can be a positive integer. The second-stage pump 32 is connected with the first-stage pump 31 through a pipeline, the second-stage pump 32 comprises a plurality of roots vacuum pumps, that is, the second-stage pump 32 comprises B roots vacuum pumps, and the value of B can be a positive integer. The first set of third-stage pump 33 is connected with the second-stage pump 32 through a pipeline, the first set of third-stage pump 33 comprises a plurality of roots vacuum pumps, the first set of third-stage pump 33 comprises C1 roots vacuum pumps, and the value of C1 can be a positive integer. The first set of fourth-stage pump 34 is respectively connected with the first set of third-stage pump 33, the second-stage pump 32 and the first RH vacuum refining furnace 1 through pipelines, the first set of fourth-stage pump 34 comprises a plurality of screw vacuum pumps, which means that the first set of fourth-stage pump 34 comprises D1 screw vacuum pumps, and the value of D1 can be a positive integer. The second set of third stage pumps 35 are connected with the second stage pump 32 through a pipeline, the second set of third stage pumps 35 comprise a plurality of roots vacuum pumps, that is, the second set of third stage pumps 35 comprise C2 roots vacuum pumps, and the value of C2 can be a positive integer. The second set of fourth-stage pump 36 is respectively connected with the second set of third-stage pump 35, the second-stage pump 32 and the second RH vacuum refining furnace 2 through pipelines, and the second set of fourth-stage pump 36 including a plurality of screw vacuum pumps may mean that the second set of fourth-stage pump 36 includes D2 screw vacuum pumps, and the value of D2 may be a positive integer.

For the valve mechanism:

the valve mechanism comprises a first control valve 41, a second control valve 42, a third control valve 43, a fourth control valve 44, a fifth control valve 45, a sixth control valve 46, a seventh control valve 47, an eighth control valve 48, a ninth control valve 49 and a tenth control valve 50, wherein the first control valve 41 is arranged between the first RH vacuum refining furnace 1 and the first stage pump 31, and the second control valve 42 is arranged between the first control valve 41 and the first stage pump 31; the third control valve 43 is installed between the second-stage pump 32 and the first set of third-stage pumps 33; the fourth control valve 44 is mounted between the first set of fourth stage pumps 34 and the second stage pump 32; the fifth control valve 45 is installed between the fourth control valve 44 and the first control valve 41; the sixth control valve 46 is installed between the second RH vacuum refining furnace 2 and the first stage pump 31, and the seventh control valve 47 is installed between the sixth control valve 46 and the first stage pump 31; the eighth control valve 48 is installed between the second stage pump 32 and the second set of third stage pumps 35; the ninth control valve 49 is installed between the eighth control valve 48 and the second set of fourth stage pumps 36; the tenth control valve 50 is installed between the ninth control valve 49 and the sixth control valve 46. The first control valve 41 is a switching valve, the second control valve 42 is a switching valve, the third control valve 43 is a switching valve, the fourth control valve 44 is a switching valve, the fifth control valve 45 is a switching valve, the sixth control valve 46 is a switching valve, the seventh control valve 47 is a switching valve, the eighth control valve 48 is a switching valve, the ninth control valve 49 is a switching valve, and the tenth control valve 50 is a switching valve.

Specifically, the switching valve can be a pneumatic switch valve, and the valve plate is opened and closed by utilizing a connecting rod structure principle. The first control valve 41, the second control valve 42, the third control valve 43, the fourth control valve 44, the fifth control valve 45, the sixth control valve 46, the seventh control valve 47, the eighth control valve 48, the ninth control valve 49, and the tenth control valve 50 may be all switching valves. A first control valve 41 is installed in the piping between the first RH vacuum refining furnace 1 and the first-stage pump 31, and the second control valve 42 is installed in the piping between the first control valve 41 and the first-stage pump 31. A third control valve 43 is installed in the piping between the second-stage pump 32 and the first set of third-stage pumps 33. A fourth control valve 44 is mounted in the conduit between the first set of fourth stage pumps 34 and the second stage pump 32. A fifth control valve 45 is installed in a pipe between the fourth control valve 44 and the first control valve 41. A sixth control valve 46 is installed in the piping between the second RH vacuum refining furnace 2 and the first-stage pump 31, and a seventh control valve 47 is installed in the piping between the sixth control valve 46 and the first-stage pump 31. An eighth control valve 48 is installed in the piping between the second stage pump 32 and the second set of third stage pumps 35. A ninth control valve 49 is mounted in the conduit between the eighth control valve 48 and the second set of fourth stage pumps 36. The tenth control valve 50 is installed in a pipe between the ninth control valve 49 and the sixth control valve 46.

It is noted that at the end of the deep vacuum state of first RH vacuum refining furnace 1 and the pre-draw state of second RH vacuum refining furnace 2, first control valve 41, second control valve 42, third control valve 43, ninth control valve 49 and tenth control valve 50 are all in the open state (i.e. the piping is open), fourth control valve 44, fifth control valve 45, sixth control valve 46, seventh control valve 47 and eighth control valve 48 are all in the closed state (i.e. the piping is closed), and at the same time, first stage pump 31, second stage pump 32, first set of third stage pump 33, first set of fourth stage pump 34 and second set of fourth stage pump 36 are all in the open state, and second set of third stage pump 35 is in the closed state. At the end of the deep vacuum phase of first RH vacuum refining furnace 1 and the rough vacuum phase of second RH vacuum refining furnace 2, first control valve 41, second control valve 42, third control valve 43, sixth control valve 46 and tenth control valve 50 are all in the open state, fourth control valve 44, fifth control valve 45, seventh control valve 47, eighth control valve 48 and ninth control valve 49 are all in the closed state, and at the same time, first stage pump 31, second stage pump 32, first set of third stage pump 33, first set of fourth stage pump 34, second set of third stage pump 35 and second set of fourth stage pump 36 are all in the open state. At the end of the pre-draw phase of the first RH vacuum refining furnace 1 and the deep vacuum phase of the second RH vacuum refining furnace 2, the fourth control valve 44, the fifth control valve 45, the sixth control valve 46, the seventh control valve 47 and the eighth control valve 48 are all in the open state, the first control valve 41, the second control valve 42, the third control valve 43, the ninth control valve 49 and the tenth control valve 50 are all in the closed state, and at the same time, the first pump 31, the second pump 32, the first set of fourth pumps 34, the second set of third pumps 35 and the second set of fourth pumps 36 are all in the open state, and the first set of third pumps 33 is in the closed state. The mechanical vacuum pump system provided by the embodiment of the invention can be shared by two RH vacuum refining furnaces, so that the first-stage pump 31 and the second-stage pump 32 are connected with the first RH vacuum refining furnace 1, and the first-stage pump 31 and the second-stage pump 32 are also connected with the second RH vacuum refining furnace 2, thereby realizing that the first-stage pump 31 in the vacuum pump mechanism is shared by the first RH vacuum refining furnace 1 and the second RH vacuum refining furnace 2, and the second-stage pump 32 in the vacuum pump mechanism is shared by the first RH vacuum refining furnace 1 and the second RH vacuum refining furnace 2, simplifying the structure, and reducing the construction cost and the production cost.

In addition, in practical operation, for light treatment steel grades, the working pressure is 6kPa to 10kPa, and when the mechanical vacuum pump system provided by the embodiment of the invention works, only the first set of third-stage pump 33, the first set of fourth-stage pump 34, the second set of third-stage pump 35 and the second set of fourth-stage pump 36 need to be started. The vacuum system occupies 22min, so that 8min of redundant time exists, and the vacuum treatment does not need to start the 1 st and 2 nd stage pumps, so that the design can completely meet the requirement of any redundant time. For the deep decarburization steel grade, the working pressure is 67Pa, and the first-stage pump 31, the second-stage pump 32, the first set of third-stage pump 33, the first set of fourth-stage pump 34, the second set of third-stage pump 35 and the second set of fourth-stage pump 36 are all started during working. Because the vacuum system occupies 30min and has no redundant time, but the first set of third-stage pump 33 and the first set of fourth-stage pump 34, the second set of third-stage pump 35 and the second set of fourth-stage pump 36 can work independently, and the pressure is reduced gradually until the time for putting the second-stage pump 32 and the first-stage pump 31 needs 8min (vacuum, oxygen blowing, coarse decarburization and the like), the mechanical vacuum pump system provided by the embodiment of the invention can meet the requirement of-8 min redundant time. For the steel grade treated (i.e. the steel grade close to the deep decarburized steel grade), the working pressure is 67Pa, and the first set of fourth pump 34 and the second set of fourth pump 36 are both started. The mechanical vacuum pump system provided by the embodiment of the invention can meet the requirement of 8min of redundant time because the vacuum system occupies 26min and has 4min of redundant time, and the first set of third-stage pump 33 and the first set of fourth-stage pump 34, the second set of third-stage pump 35 and the second set of fourth-stage pump 36 can work independently, and the pressure is reduced gradually until the time for inputting the second-stage pump 32 and the first-stage pump 31 needs 4 min.

The invention provides a mechanical vacuum pump system, wherein a first stage pump 31 in a vacuum pump mechanism is respectively connected with a first RH vacuum refining furnace 1 and a second RH vacuum refining furnace 2, a second stage pump 32 is connected with the first stage pump 31, a first set of third stage pump 33 is connected with the second stage pump 32, a first set of fourth stage pump 34 is respectively connected with the first set of third stage pump 33, the second stage pump 32 and the first RH vacuum refining furnace 1, a second set of third stage pump 35 is connected with the second stage pump 32, a second set of fourth stage pump 36 is respectively connected with the second set of third stage pump 35, the second stage pump 32 and the second RH vacuum refining furnace 2, a first control valve 41 in the valve mechanism is arranged between the first RH vacuum refining furnace 1 and the first stage pump 31, a second control valve 42 is arranged between the first control valve 41 and the first stage pump 31, a third control valve 43 is arranged between the second stage pump 32 and the first set of third stage pump 33, the fourth control valve 44 is installed between the first set of the fourth stage pump 34 and the second stage pump 32, the fifth control valve 45 is installed between the fourth control valve 44 and the first control valve 41, the sixth control valve 46 is installed between the second RH vacuum refining furnace 2 and the first stage pump 31, the seventh control valve 47 is installed between the sixth control valve 46 and the first stage pump 31, the eighth control valve 48 is installed between the second stage pump 32 and the second set of the third stage pump 35, the ninth control valve 49 is installed between the eighth control valve 48 and the second set of the fourth stage pump 36, and the tenth control valve 50 is installed between the ninth control valve 49 and the sixth control valve 46. Like this first order pump 31 and second level pump 32 are connected with first RH vacuum refining furnace 1, and first order pump 31 and second level pump 32 also are connected with second RH vacuum refining furnace 2, realize first order pump 31 in the vacuum pump mechanism is shared to first RH vacuum refining furnace 1 and second RH vacuum refining furnace 2, and second level pump 32 in the vacuum pump mechanism is shared to first RH vacuum refining furnace 1 and second RH vacuum refining furnace 2, can simplify the structure, reduce construction cost and manufacturing cost, thereby reached and simplified the structure, reduce construction cost and manufacturing cost's technological effect.

In order to describe the control method of the mechanical vacuum pump system provided by the invention in detail, the above embodiment describes one-to-one mechanical vacuum pump system in detail, and based on the same inventive concept, the application also provides a control method of the mechanical vacuum pump system, which is described in detail in embodiment two.

Example two

Referring to fig. 4, fig. 4 is a flowchart illustrating a method for controlling a mechanical vacuum pump system according to an embodiment of the present invention, and a second embodiment of the present invention provides a method for controlling a mechanical vacuum pump system, including: step S1, when the first RH vacuum refining furnace 1 is in the end of the deep vacuum state and the second RH vacuum refining furnace 2 is in the pre-pumping state, opening the first control valve 41, the second control valve 42, the third control valve 43, the ninth control valve 49, and the tenth control valve 50, closing the fourth control valve 44, the fifth control valve 45, the sixth control valve 46, the seventh control valve 47, and the eighth control valve 48, and opening the first pump 31, the second pump 32, the first set of third pumps 33, the first set of fourth pumps 34, and the second set of fourth pumps 36, and closing the second set of third pumps 35;

step S2, when the first RH vacuum refining furnace 1 is in the end of the deep vacuum state and the second RH vacuum refining furnace 2 is in the rough vacuum state, opening the first control valve 41, the second control valve 42, the third control valve 43, the sixth control valve 46 and the tenth control valve 50, closing the fourth control valve 44, the fifth control valve 45, the seventh control valve 47, the eighth control valve 48 and the ninth control valve 49, and opening the first stage pump 31, the second stage pump 32, the first set of third stage pump 33, the first set of fourth stage pump 34, the second set of third stage pump 35 and the second set of fourth stage pump 36;

step S3, when the first RH vacuum refining furnace 1 is in the pre-pumping state and the second RH vacuum refining furnace 2 is at the end of the deep vacuum state, opening the fourth control valve 44, the fifth control valve 45, the sixth control valve 46, the seventh control valve 47, and the eighth control valve 48, closing the first control valve 41, the second control valve 42, the third control valve 43, the ninth control valve 49, and the tenth control valve 50, and opening the first pump 31, the second pump 32, the first set of the fourth pump 34, the second set of the third pump 35, and the second set of the fourth pump 36, and closing the first set of the third pump 33; circularly executing the step S1, the step S2 and the step S3. Wherein the first-stage pump 31 comprises a plurality of roots vacuum pumps; the second-stage pump 32 comprises a plurality of roots vacuum pumps; the first set of third stage pumps 33 comprises a plurality of roots vacuum pumps; the first set of fourth stage pumps 34 comprises a plurality of screw vacuum pumps. The second set of third stage pumps 35 comprises a plurality of roots vacuum pumps; the second set of fourth stage pumps 36 comprises a plurality of screw vacuum pumps. The first control valve 41 is a switching valve, the second control valve 42 is a switching valve, the third control valve 43 is a switching valve, the fourth control valve 44 is a switching valve, the fifth control valve 45 is a switching valve, the sixth control valve 46 is a switching valve, the seventh control valve 47 is a switching valve, the eighth control valve 48 is a switching valve, the ninth control valve 49 is a switching valve, and the tenth control valve 50 is a switching valve. The first RH vacuum refining furnace 1 is capable of processing a first target molten steel including a light-treated steel grade, a present-treated steel grade, or a deep decarburized steel grade; the second RH vacuum refining furnace 2 is configured to process a second target molten steel including a light-treated steel grade, a present-treated steel grade, or a deep decarburized steel grade.

The invention provides a control method of a mechanical vacuum pump system, through step S1, when a first RH vacuum refining furnace 1 is in the end of a deep vacuum state and a second RH vacuum refining furnace 2 is in a pre-pumping state, opening a first control valve 41, a second control valve 42, a third control valve 43, a ninth control valve 49 and a tenth control valve 50, closing a fourth control valve 44, a fifth control valve 45, a sixth control valve 46, a seventh control valve 47 and an eighth control valve 48, opening a first pump 31, a second pump 32, a first set of third pumps 33, a first set of fourth pumps 34 and a second set of fourth pumps 36, and closing the second set of third pumps 35; step S2, when the first RH vacuum refining furnace 1 is in the end of the deep vacuum state and the second RH vacuum refining furnace 2 is in the rough vacuum state, opening the first control valve 41, the second control valve 42, the third control valve 43, the sixth control valve 46 and the tenth control valve 50, closing the fourth control valve 44, the fifth control valve 45, the seventh control valve 47, the eighth control valve 48 and the ninth control valve 49, and opening the first stage pump 31, the second stage pump 32, the first set of third stage pump 33, the first set of fourth stage pump 34, the second set of third stage pump 35 and the second set of fourth stage pump 36; step S3, when the first RH vacuum refining furnace 1 is in the pre-pumping state and the second RH vacuum refining furnace 2 is at the end of the deep vacuum state, opening the fourth control valve 44, the fifth control valve 45, the sixth control valve 46, the seventh control valve 47, and the eighth control valve 48, closing the first control valve 41, the second control valve 42, the third control valve 43, the ninth control valve 49, and the tenth control valve 50, and opening the first pump 31, the second pump 32, the first set of the fourth pump 34, the second set of the third pump 35, and the second set of the fourth pump 36, and closing the first set of the third pump 33; circularly executing the step S1, the step S2 and the step S3. Like this first order pump 31 and second level pump 32 are connected with first RH vacuum refining furnace 1, and first order pump 31 and second level pump 32 also are connected with second RH vacuum refining furnace 2, realize first order pump 31 in the vacuum pump mechanism is shared to first RH vacuum refining furnace 1 and second RH vacuum refining furnace 2, and second level pump 32 in the vacuum pump mechanism is shared to first RH vacuum refining furnace 1 and second RH vacuum refining furnace 2, can simplify the structure, reduce construction cost and manufacturing cost, thereby reached and simplified the structure, reduce construction cost and manufacturing cost's technological effect.

Finally, it should be noted that the above embodiments are only for illustrating the technical solutions of the present invention and not for limiting, and although the present invention has been described in detail with reference to examples, it should be understood by those skilled in the art that modifications or equivalent substitutions may be made on the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, which should be covered by the claims of the present invention.

Claims

1. A mechanical vacuum pump system, the system comprising:

a first RH vacuum refining furnace and a second RH vacuum refining furnace;

the vacuum pump mechanism comprises a first-stage pump, a second-stage pump, a first set of third-stage pump, a first set of fourth-stage pump, a second set of third-stage pump and a second set of fourth-stage pump, and the first-stage pump is respectively connected with a first RH vacuum refining furnace and a second RH vacuum refining furnace; the second-stage pump is connected with the first-stage pump; the first set of third-stage pump is connected with the second-stage pump; the first set of fourth-stage pump is respectively connected with the first set of third-stage pump, the second-stage pump and the first RH vacuum refining furnace; the second set of third stage pump is connected with the second stage pump; the second set of fourth-stage pump is respectively connected with the second set of third-stage pump, the second-stage pump and the second RH vacuum refining furnace;

the valve mechanism comprises a first control valve, a second control valve, a third control valve, a fourth control valve, a fifth control valve, a sixth control valve, a seventh control valve, an eighth control valve, a ninth control valve and a tenth control valve, the first control valve is installed between a first RH vacuum refining furnace and a first-stage pump, and the second control valve is installed between the first control valve and the first-stage pump; the third control valve is arranged between the second-stage pump and the first set of third-stage pumps; the fourth control valve is arranged between the first set of fourth-stage pump and the second set of fourth-stage pump; the fifth control valve is arranged between the fourth control valve and the first control valve; the sixth control valve is arranged between the second RH vacuum refining furnace and the first-stage pump, and the seventh control valve is arranged between the sixth control valve and the first-stage pump; the eighth control valve is arranged between the second-stage pump and the second set of third-stage pump; the ninth control valve is arranged between the eighth control valve and the second set of fourth-stage pumps; the tenth control valve is installed between the ninth control valve and the sixth control valve.

2. The mechanical vacuum pump system of claim 1, wherein:

the first-stage pump comprises a plurality of roots vacuum pumps; the second-stage pump comprises a plurality of roots vacuum pumps; the first set of third-stage pumps comprises a plurality of roots vacuum pumps; the first set of fourth stage pumps comprises a plurality of screw vacuum pumps.

3. The mechanical vacuum pump system of claim 1, wherein:

the second set of third-stage pump comprises a plurality of roots vacuum pumps; the second set of fourth stage pumps comprises a plurality of screw vacuum pumps.

4. The mechanical vacuum pump system of claim 1, wherein:

the first control valve is a switching valve, the second control valve is a switching valve, the third control valve is a switching valve, the fourth control valve is a switching valve, the fifth control valve is a switching valve, the sixth control valve is a switching valve, the seventh control valve is a switching valve, the eighth control valve is a switching valve, the ninth control valve is a switching valve, and the tenth control valve is a switching valve.

5. The mechanical vacuum pump system of claim 1, wherein:

the first RH vacuum refining furnace can be used for treating first target molten steel, and the first target molten steel comprises a light treatment steel grade, a present treatment steel grade or a deep decarburization steel grade; the second RH vacuum refining furnace is configured to process a second target molten steel, which includes a light-treated steel grade, a present-treated steel grade, or a deep decarburized steel grade.

6. A method of controlling a mechanical vacuum pump system, the method comprising:

step S1, when the first RH vacuum refining furnace is in the end of the deep vacuum state and the second RH vacuum refining furnace is in the pre-pumping state, opening the first control valve, the second control valve, the third control valve, the ninth control valve and the tenth control valve, closing the fourth control valve, the fifth control valve, the sixth control valve, the seventh control valve and the eighth control valve, opening the first pump, the second pump, the first set of third pumps, the first set of fourth pumps and the second set of fourth pumps, and closing the second set of third pumps;

step S2, when the first RH vacuum refining furnace is in the end of the deep vacuum state and the second RH vacuum refining furnace is in the rough vacuum state, opening the first control valve, the second control valve, the third control valve, the sixth control valve and the tenth control valve, closing the fourth control valve, the fifth control valve, the seventh control valve, the eighth control valve and the ninth control valve, and opening the first pump, the second pump, the first set of third pumps, the first set of fourth pumps, the second set of third pumps and the second set of fourth pumps;

step S3, when the first RH vacuum refining furnace is in a pre-pumping state and the second RH vacuum refining furnace is in a deep vacuum state, opening a fourth control valve, a fifth control valve, a sixth control valve, a seventh control valve and an eighth control valve, closing the first control valve, the second control valve, the third control valve, the ninth control valve and the tenth control valve, opening a first pump, a second pump, a first set of fourth-stage pumps, a second set of third-stage pumps and a second set of fourth-stage pumps, and closing the first set of third-stage pumps; circularly executing the step S1, the step S2 and the step S3.

7. The method of controlling a mechanical vacuum pump system of claim 6, wherein:

8. The method of controlling a mechanical vacuum pump system of claim 6, wherein:

9. The method of controlling a mechanical vacuum pump system of claim 6, wherein:

10. The method of controlling a mechanical vacuum pump system of claim 6, wherein: