CN212615397U

CN212615397U - Frosting prevention device for cryogenic liquid pump

Info

Publication number: CN212615397U
Application number: CN202020503651.3U
Authority: CN
Inventors: 姚力; 倪志强; 刘永东; 刘兰涛; 杨立志
Original assignee: Tangshan Tangsteel Gas Co ltd
Current assignee: Tangshan Tangsteel Gas Co ltd
Priority date: 2020-04-09
Filing date: 2020-04-09
Publication date: 2021-02-26
Anticipated expiration: 2030-04-09

Abstract

The utility model relates to a frosting prevention device for cryogenic liquid pump belongs to cryogenic liquid supercharging equipment technical field. Comprises a connecting pipeline (5), a pressure gauge (6), an adjusting valve (7) and two sealing shaft sleeves (3); the two sealing shaft sleeves (3) penetrate through the fixing bolt holes (12) through bolts to be fixedly connected, the connecting pipeline (5) is respectively connected with the sealing air connectors (13) of the two sealing shaft sleeves (3), and the upper end of the connecting pipeline (5) is sequentially provided with the adjusting valve (7) and the pressure gauge (6). The device solves the problem of icing at the sealing part of the low-temperature liquid pump body, reduces the leakage of low-temperature liquid, reduces the leakage of liquid while ensuring safe production, can ensure safe and efficient operation of the low-temperature liquid pump, ensures timely supply of gas, and has remarkable economic and social benefits.

Description

Frosting prevention device for cryogenic liquid pump

Technical Field

The utility model relates to a frosting prevention device for cryogenic liquid pump belongs to cryogenic liquid supercharging equipment technical field.

Background

Cryogenic liquid pumps are special pumps used to transport cryogenic liquids (such as liquid oxygen, liquid nitrogen, liquid argon, liquid hydrocarbons, liquefied natural gas, etc.). In the air separation field, the cryogenic liquid pump is mainly used for conveying liquid products, such as liquid oxygen pumps, liquid nitrogen pumps, liquid argon pumps and other liquid pumps, and is used for conveying cryogenic liquid from a place with low pressure to a place with high pressure, such as pressurizing the liquid product in a storage tank, then feeding the pressurized liquid product into a vaporizer, and then feeding the vaporized liquid product to users. According to different working principles, cryogenic liquid pumps are mainly classified into a reciprocating type and a centrifugal type. The working principle of the centrifugal low-temperature liquid pump is the same as that of a centrifugal water pump. The rotating impeller is used to do work on the liquid and transfer the mechanical energy of the prime mover to the liquid, so as to raise the pressure of the liquid.

However, the cryogenic liquid pump is different from a general pump in that it is required to maintain a low temperature during the liquid transfer process to minimize the cold loss, otherwise the cryogenic pump may not work due to vaporization of the liquid. In order to prevent vaporization of the cryogenic liquid, the pump body and the inlet pipeline must be insulated and insulated, and pearlife or foaming materials are generally used. The sealing is one of the key parts in the cryogenic liquid pump, and the sealing of the pump adopts a closed type or a shaft sealing type. There are three types of shaft seals: mechanical seals, labyrinth seals and stuffing box seals. For the pump with lower temperature, mechanical seal is usually adopted, but no matter which kind of seal can inevitably produce liquid leakage, after the low-temperature liquid leakage, the moisture in the air is desublimated into frost, after long-time operation, ice is formed at the seal and the rotating shaft, so that the rotation of the shaft is blocked, the power consumption is increased, the service lives of the liquid pump and the motor are reduced, if the low-temperature liquid pump is not used for a long time, the motor is easily burnt when the shaft and the seal are restarted, and the normal air supply can not be carried out, thereby influencing the steel production.

In order to prevent the low-temperature liquid pump body sealing part from icing, the following technical problems must be solved:

1. the seal must be effectively isolated from moisture in the air;

2. the low-temperature liquid and the low-temperature gas leaked from the sealing position are required to be quickly vaporized and heated, so that the low-temperature gas is prevented from de-subliming water into frost;

3. the leakage amount of low-temperature liquid and low-temperature gas at the sealing position is reduced as much as possible;

therefore, there is a need for a cryogenic liquid pump anti-frosting device that can solve the above problems.

SUMMERY OF THE UTILITY MODEL

The utility model aims to solve the technical problem that a frosting prevention device is provided to cryogenic liquid pump, this kind of frosting prevention device of cryogenic liquid pump can prevent that the sealed department of liquid pump from frosting to can adjust purge gas pressure, thereby satisfy the demand of different pressure liquid pumps, reach the purpose that reduces sealed department liquid leakage.

The technical scheme for solving the technical problems is as follows:

a frosting prevention device for a cryogenic liquid pump comprises a connecting pipeline, a pressure gauge, an adjusting valve and two sealing shaft sleeves; the sealing shaft sleeve comprises a sealing air injection hole, a sealing partition plate, a fixing bolt hole, a sealing air connector, a shaft sleeve shell cavity, a shaft sleeve isolation cavity, a shaft sleeve outer shell, a shaft sleeve inner shell and a connecting plate, and the sealing shaft sleeve is of a semi-cylindrical structure formed by the shaft sleeve outer shell and the shaft sleeve inner shell; a shaft sleeve shell cavity is formed between the shaft sleeve outer shell and the shaft sleeve inner shell, and a shaft sleeve isolation cavity is formed in the shaft sleeve inner shell; a sealing air joint is arranged on the shaft sleeve shell and is communicated with the shaft sleeve shell cavity; the upper part of the shaft sleeve inner shell is provided with a sealing air injection hole, and a shaft sleeve shell cavity is communicated with a shaft sleeve isolation cavity; a sealing clapboard is arranged at the lower part of the inner shell of the shaft sleeve; connecting plates are arranged on the outer sides of semicircular diameter openings on two sides of the sealing shaft sleeve, and fixing bolt holes are arranged on the connecting plates; semicircular gaps are formed in the semicircular central parts of the shaft sleeve outer shell, the shaft sleeve inner shell and the sealing partition plate, and the size of each gap is matched with that of the rotating shaft; the two sealing shaft sleeves penetrate through the fixing bolt holes through bolts to be tightly connected, the connecting pipeline is respectively connected with the sealing air connectors of the two sealing shaft sleeves, and the upper end of the connecting pipeline is sequentially provided with an adjusting valve and a pressure gauge.

The side opening part of the sealing shaft sleeve is provided with a sealing gasket, the central semicircular gap part of the upper end surface of the sealing shaft sleeve is provided with a sealing rubber ring, and the inner diameter size of the sealing rubber ring is matched with the size of the pump body seal.

The inner diameter of the shaft sleeve outer shell is 230-340 mm, and the inner diameter of the shaft sleeve inner shell is 200-300 mm.

The diameter of the sealing gas injection holes is 4-8 mm, and the number of the sealing gas injection holes is 60-120.

The thickness of the sealing partition plate is 2-4 mm, and the number of the sealing partition plates is 8-14.

A central hole is formed in the sealing partition plate, and a 1 mm gap is reserved between the central hole and the rotating main shaft and serves as a gas channel.

The utility model discloses useful part lies in: this device simple structure, separate good, the pressure is adjustable of nature, can satisfy the demand of different liquid pumps, and the installation is simple simultaneously, can effectually keep apart the moisture in low-temperature gas and the air, keeps apart the chamber and forms the malleation environment, can effectual reduction cryogenic liquids's leakage. The anti-frosting method of the device solves the problem of icing at the sealing position of the low-temperature liquid pump body, reduces leakage of low-temperature liquid, ensures safe production, reduces leakage of liquid, can ensure safe and efficient operation of the low-temperature liquid pump, ensures timely supply of gas, and has remarkable economic and social benefits.

Drawings

FIG. 1 is a front view of the device of the present invention;

fig. 2 is a top view of the inventive apparatus;

fig. 3 is a side view of the inventive apparatus;

FIG. 4 is a schematic view of the device according to the present invention in use;

fig. 5 is a cross-sectional view of the inventive apparatus;

fig. 6 is a cross-sectional view of the inventive apparatus;

the figures are labeled as follows: the low-temperature liquid pump comprises a low-temperature liquid pump body 1, a liquid pump seal 2, a seal shaft sleeve 3, a motor 4, a connecting pipeline 5, a pressure gauge 6, an adjusting valve 7, a seal gasket 8, a seal rubber ring 9, a seal air injection hole 10, a seal partition plate 11, a fixing bolt hole 12, a seal air joint 13, a shaft sleeve shell cavity 14, a shaft sleeve isolation cavity 15, a shaft sleeve outer shell 16, a shaft sleeve inner shell 17, a connecting plate 18 and a rotating shaft 19.

Detailed Description

The invention will be further explained by way of example with reference to the accompanying drawings.

As shown in the attached drawing, the anti-frosting device for the cryogenic liquid pump comprises a connecting pipeline 5, a pressure gauge 6, an adjusting valve 7 and two sealing shaft sleeves 3; the sealing shaft sleeve 3 comprises a sealing air injection hole 10, a sealing partition plate 11, a fixing bolt hole 12, a sealing air connector 13, a shaft sleeve shell cavity 14, a shaft sleeve isolation cavity 15, a shaft sleeve outer shell 16, a shaft sleeve inner shell 17 and a connecting plate 18, and the sealing shaft sleeve 3 is of a semi-cylindrical structure formed by the shaft sleeve outer shell 16 and the shaft sleeve inner shell 17; a shaft sleeve shell cavity 14 is formed between the shaft sleeve outer shell 16 and the shaft sleeve inner shell 17, and a shaft sleeve isolation cavity 15 is formed in the shaft sleeve inner shell 17; a sealing air joint 13 is arranged on the shaft sleeve shell 16 and is communicated with a shaft sleeve shell cavity 14; the upper part of the shaft sleeve inner shell 17 is provided with a sealing air injection hole 10, and a shaft sleeve shell cavity 14 is communicated with a shaft sleeve isolation cavity 15; a sealing clapboard 11 is arranged at the lower part of the shaft sleeve inner shell 17; the outer sides of semicircular diameter openings at two sides of the sealing shaft sleeve 3 are provided with connecting plates 18, and the connecting plates 18 are provided with fixing bolt holes 12; the semi-circular central parts of the shaft sleeve outer shell 16, the shaft sleeve inner shell 17 and the sealing partition plate 11 are provided with semi-circular gaps, and the sizes of the gaps are matched with the size of the rotating shaft 19; the two sealing shaft sleeves 3 penetrate through the fixing bolt holes 12 through bolts to be tightly connected, the connecting pipeline 5 is respectively connected with the sealing air connectors 13 of the two sealing shaft sleeves 3, and the upper end of the connecting pipeline 5 is sequentially provided with the adjusting valve 7 and the pressure gauge 6. The side opening part of the sealing shaft sleeve 3 is provided with a sealing gasket 8, the central semicircular gap part of the upper end surface is provided with a sealing rubber ring 9, and the inner diameter size of the sealing rubber ring 9 is matched with the size of the pump body seal 2. The inner diameter of the shaft sleeve outer shell 16 is 230 mm, and the inner diameter of the shaft sleeve inner shell 17 is 200 mm. The diameter of the seal gas injection hole 10 is 4 mm, and the number thereof is 60. The thickness of the sealing partition plate 11 is 2 mm, and the number of the sealing partition plates is 8. A central hole is formed in the sealing partition plate 11, and a 1 mm gap is reserved between the central hole and the rotating main shaft to serve as a gas channel.

The method for preventing the low-temperature liquid pump from frosting by adopting the device for preventing the low-temperature liquid pump from frosting comprises the following steps:

a. the two sealing shaft sleeves 3 are sleeved on the rotating shaft 19 at the outer side of the liquid pump seal 2, the two sealing shaft sleeves 3 are fixedly connected by bolts penetrating through the fixing bolt holes 12, the upper end faces of the sealing shaft sleeves 3 and the pump body seal 2 are compacted by the sealing rubber rings 9, and the position is kept sealed and airtight;

b. connecting the upper end of the connecting pipeline 5 with a high-pressure drying air source;

c. and opening the regulating valve 7, introducing high-pressure dry gas into the sealing shaft sleeve 3 through the connecting pipeline 5, and keeping the gas pressure in the shaft sleeve isolation cavity 15 lower than the pressure in the low-temperature liquid pump body 1, thereby effectively reducing the leakage of the low-temperature liquid.

The moisture content of the drying gas was 30 ppm.

When the low-temperature liquid pump body 1 is opened, the pressure of the introduced high-pressure drying gas is 0.35 MPa. The proper pressure lower than the working pressure of the liquid pump can be kept in the sealed shaft sleeve isolation cavity 15 by adjusting the valve 7 according to the working pressure of the liquid pump, and the leakage amount of the low-temperature liquid is reduced while air is isolated.

When the low-temperature liquid pump body 1 is closed, the pressure of the introduced high-pressure drying gas is 0.058 MPa. The regulating valve 7 always keeps a small opening degree, so that the inner cavity 15 of the sealing shaft sleeve is in a micro-positive pressure state to effectively isolate air.

This device simple structure, separate good, the pressure is adjustable of nature, can satisfy the demand of different liquid pumps, and the installation is simple simultaneously, can effectually keep apart the moisture in low-temperature gas and the air, keeps apart the chamber and forms the malleation environment, can effectual reduction cryogenic liquids's leakage. The anti-frosting method of the device solves the problem of icing at the sealing position of the low-temperature liquid pump body, reduces leakage of low-temperature liquid, ensures safe production, reduces leakage of liquid, can ensure safe and efficient operation of the low-temperature liquid pump, ensures timely supply of gas, and has remarkable economic and social benefits.

Claims

1. A frosting prevention device for a cryogenic liquid pump is characterized by comprising a connecting pipeline (5), a pressure gauge (6), an adjusting valve (7) and two sealing shaft sleeves (3);

the sealing shaft sleeve (3) comprises a sealing air injection hole (10), a sealing partition plate (11), a fixing bolt hole (12), a sealing air joint (13), a shaft sleeve shell cavity (14), a shaft sleeve isolation cavity (15), a shaft sleeve outer shell (16), a shaft sleeve inner shell (17) and a connecting plate (18), and the sealing shaft sleeve (3) is of a semi-cylindrical structure formed by the shaft sleeve outer shell (16) and the shaft sleeve inner shell (17); a shaft sleeve shell cavity (14) is formed between the shaft sleeve outer shell (16) and the shaft sleeve inner shell (17), and a shaft sleeve isolation cavity (15) is formed in the shaft sleeve inner shell (17); a sealing air joint (13) is arranged on the shaft sleeve shell (16) and is communicated with the shaft sleeve shell cavity (14); a sealing air injection hole (10) is formed in the upper portion of the shaft sleeve inner shell (17), and a shaft sleeve shell cavity (14) is communicated with a shaft sleeve isolation cavity (15); a sealing clapboard (11) is arranged at the lower part of the shaft sleeve inner shell (17); a connecting plate (18) is arranged at the outer side of the semicircular diameter openings at the two sides of the sealing shaft sleeve (3), and a fixing bolt hole (12) is arranged on the connecting plate (18); semicircular gaps are formed in the semicircular central parts of the shaft sleeve outer shell (16), the shaft sleeve inner shell (17) and the sealing partition plate (11), and the sizes of the gaps are matched with the size of the rotating shaft (19);

the two sealing shaft sleeves (3) penetrate through the fixing bolt holes (12) through bolts to be fixedly connected, the connecting pipeline (5) is respectively connected with the sealing air connectors (13) of the two sealing shaft sleeves (3), and the upper end of the connecting pipeline (5) is sequentially provided with the adjusting valve (7) and the pressure gauge (6).

2. The anti-frosting device for the cryogenic liquid pump, according to claim 1, is characterized in that the sealing gasket (8) is disposed at the side opening of the sealing shaft sleeve (3), the sealing rubber ring (9) is disposed at the central semicircular gap of the upper end surface, and the inner diameter of the sealing rubber ring (9) is matched with the pump body seal (2).

3. The anti-frosting device for cryogenic liquid pump as claimed in claim 1, wherein the inner diameter of said shaft sleeve outer shell (16) is 230-340 mm, and the inner diameter of said shaft sleeve inner shell (17) is 200-300 mm.

4. The anti-frosting apparatus for cryogenic liquid pump as claimed in claim 1, wherein said sealing gas injection holes (10) have a diameter of 4-8 mm and a number of 60-120.

5. The anti-frosting device for cryogenic liquid pump according to claim 1, wherein the thickness of the sealing partition (11) is 2-4 mm, and the number is 8-14.

6. The anti-frosting device for cryogenic liquid pump, according to claim 5, wherein the sealing partition (11) is provided with a central hole, and a 1 mm gap is left between the central hole and the main rotating shaft as a gas passage.