Nitrogen purging device for cryopump

Abstract

The nitrogen purging device for the low-temperature pump comprises a supporting table, the supporting table is used for containing the low-temperature pump, a nitrogen supply device is arranged on the supporting table, the nitrogen supply device is connected with a gas pipe, the gas pipe is connected with a nitrogen purging ring, and the nitrogen purging ring is movably arranged at the mechanical seal part of the driving end of the low-temperature pump in a sleeving mode. The nitrogen purging ring is used for blowing nitrogen to the driving end mechanical seal part of the low-temperature pump, the supporting table is further provided with a swing mechanism, the swing mechanism is used for driving the nitrogen purging ring to rotate back and forth at the corresponding amplitude, and the low-temperature pump has the advantages that the purging sufficiency of the whole mechanical seal part of the low-temperature pump can be improved, and the freezing risk of the mechanical seal part of the low-temperature pump is reduced.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of cryogenic pump protection, and particularly relates to a nitrogen blowing device for a cryogenic pump. BACKGROUND

[0002] A cryogenic liquid pump (referred to as a cryogenic pump) is a special pump used for conveying cryogenic liquids (such as liquid oxygen, liquid nitrogen, liquid argon, liquid hydrocarbon and liquefied natural gas) in petroleum, air separation and chemical plants. When the cryogenic pump is not running, especially in winter or in cold regions, the driving end seal part is prone to icing. When it needs to be used, the ice needs to be removed in a tool mechanical destructive manner, which not only is low in efficiency, but also is prone to damage to the seal structure and affects the normal operation of the cryogenic pump.

[0003] In order to solve the problem that the seal part of the cryogenic pump is prone to icing, a nitrogen blowing device is currently designed, which can continuously blow nitrogen to the seal part of the cryogenic pump to prevent icing. However, the existing nitrogen blowing device has a simple structure, a limited blowing area and can only blow nitrogen to the seal part of the cryogenic pump locally, so that the blowing is insufficient and there is still a risk of local icing of the seal part of the cryogenic pump. CONTENT OF THE UTILITY MODEL

[0004] The main purpose of the application is to provide a nitrogen blowing device for a cryogenic pump, which aims to solve the technical problem that the existing nitrogen blowing device cannot sufficiently blow the entire seal part of the cryogenic pump.

[0005] In order to achieve the above-mentioned purpose, the application provides a nitrogen blowing device for a cryogenic pump, which comprises a support table for placing the cryogenic pump, a nitrogen supply device arranged on the support table, a gas pipe connected to the nitrogen supply device, a nitrogen blowing ring connected to the gas pipe, the nitrogen blowing ring movably sleeving the driving end seal part of the cryogenic pump, the nitrogen blowing ring being used for blowing nitrogen to the driving end seal part of the cryogenic pump, and a swing mechanism arranged on the support table and used for driving the nitrogen blowing ring to reciprocatingly rotate at a corresponding amplitude.

[0006] Optionally, the swing mechanism comprises an arc-shaped rack arranged at the bottom of the nitrogen blowing ring, the arc-shaped rack being meshingly connected with a straight rack, the straight rack being slidingly arranged on the support table, and the support table being provided with a driving mechanism used for driving the straight rack to reciprocatingly move.

[0007] Optionally, a guide sliding groove matched with the straight rack is formed in the top of the support table, the driving mechanism comprises a driving motor arranged at the top of the support table, a driving-connected output shaft movably extending into the guide sliding groove and being connected with a cam, the cam being used for contacting one side wall of the straight rack, the other side wall of the straight rack being connected with a compression spring, and the other end of the compression spring being connected to the corresponding wall of the guide sliding groove.

[0008] Optionally, the nitrogen purging ring is provided with an annular air cavity, the outer wall of the nitrogen purging ring is provided with an inlet port in communication with the annular air cavity, the inlet port is connected with the air pipe, the outer wall of the nitrogen purging ring is provided with a plurality of air outlets in communication with the annular air cavity, and the plurality of air outlets are arranged in an annular array.

[0009] Optionally, the inner diameter of the air outlet gradually decreases away from the annular air cavity.

[0010] Optionally, the support table is provided with a support seat, the support seat is adjustable in height, the top of the support seat is provided with an arc-shaped clamping plate for clamping the cryogenic pump, and the two side walls of the arc-shaped clamping plate are threadedly connected with a plurality of fastening screws for abutting against the cryogenic pump.

[0011] Optionally, the support table is provided with a receiving cavity, the support seat comprises a first wedge block slidingly arranged at the bottom of the receiving cavity, the top surface of the first wedge block is slidingly provided with a second wedge block, one side of the first wedge block and the second wedge block in contact with each other is a bevel surface, the second wedge block is movably penetrated through the top of the support table, the arc-shaped clamping plate is arranged on the top of the second wedge block, and one side wall of the first wedge block is connected with a push-pull piece for sliding the first wedge block.

[0012] Optionally, the push-pull piece comprises a movable bearing arranged on the side wall of the first wedge block, the movable bearing is connected with a rotating handle, the rotating handle is penetrated through the side wall of the support table, and the rotating handle is provided with a threaded segment threadedly matched with the side wall of the support table.

[0013] The beneficial effects that can be achieved by the present application are as follows:

[0014] The present application comprises a support table for placing a cryogenic pump, the support table is provided with a nitrogen supply device, the nitrogen supply device is connected with an air pipe, the air pipe is connected with a nitrogen purging ring, the nitrogen purging ring is movably sleeved on the drive end mechanical seal part of the cryogenic pump, the nitrogen purging ring is used for blowing nitrogen to the drive end mechanical seal part of the cryogenic pump, the support table is further provided with an oscillating mechanism, and the oscillating mechanism is used for driving the nitrogen purging ring to reciprocatingly rotate at a corresponding amplitude. Based on the structure of the present application, when the cryogenic pump is temporarily not needed, the cryogenic pump is placed on the support table, then the nitrogen purging ring is sleeved and installed on the drive end mechanical seal part of the cryogenic pump, the nitrogen supply device is started to supply nitrogen, so that the drive end mechanical seal part of the cryogenic pump is purged by the nitrogen purging ring, and under the action of the oscillating mechanism, the nitrogen purging ring can be driven to reciprocatingly rotate at a corresponding amplitude, so that the air port of the nitrogen purging ring reciprocatingly rotates around the drive end mechanical seal part of the cryogenic pump, thereby the purging area can be increased, the purging completeness is improved, and the risk of icing of the mechanical seal part of the cryogenic pump is reduced. BRIEF DESCRIPTION OF DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the specific embodiments or the prior art of the present application, the drawings needed to be used in the description of the specific embodiments or the prior art will be briefly introduced below. In all the drawings, similar elements or parts are generally identified by similar reference signs. In the drawings, the elements or parts are not necessarily drawn according to the actual proportions.

[0016] Fig. 1 A structure schematic diagram of a nitrogen purging device for a cryogenic pump in an embodiment of the present application;

[0017] Fig. 2 A structure schematic diagram of a nitrogen purging device for a cryogenic pump in an embodiment of the present application;

[0018] Fig. 3 A connection structure schematic diagram of a nitrogen purging ring, a swing mechanism and a driving mechanism based on a side view in an embodiment of the present application.

[0019] Reference signs:

[0020] 110 - support table, 111 - guide chute, 112 - containing cavity, 120 - cryogenic pump, 130 - nitrogen supply device, 140 - gas pipe, 150 - nitrogen purging ring, 151 - annular gas cavity, 152 - inlet, 153 - gas outlet hole, 160 - swing mechanism, 161 - arc-shaped rack, 162 - straight rack, 170 - driving mechanism, 171 - driving motor, 172 - cam, 180 - compression spring, 190 - support seat, 191 - first wedge block, 192 - second wedge block, 210 - arc-shaped clamping plate, 220 - fastening screw, 230 - push-pull piece, 231 - movable bearing, 232 - rotating handle.

[0021] The implementation, functional features and advantages of the present application will be further described with reference to the embodiments in combination with the drawings. DETAILED DESCRIPTION

[0022] The technical solutions in the embodiments of the present application will be described clearly and completely below in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all the other embodiments obtained by those skilled in the art without any creative work under the premise that the present application falls within the scope of protection.

[0023] It should be noted that all the directionality indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present application are only used to explain the relative position relationship, movement condition, etc. between the components in a certain specific posture, and if the specific posture changes, the directionality indications will also change accordingly.

[0024] In this application, unless otherwise clearly specified and limited, the terms "connection", "fixation" and the like should be understood in a broad sense, for example, "connection" can be fixed connection, or detachable connection, or integral; can be mechanical connection, or electrical connection; can be directly connected, or indirectly connected through an intermediate medium, can be internal communication of two elements or interaction relationship between two elements, unless otherwise clearly limited. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

[0025] In addition, if the description of "first", "second" and the like is involved in the embodiments of the present application, the description of "first", "second" and the like is only for the purpose of description, and cannot be understood as indicating or implying the relative importance of the indicated technical features or implicitly indicating the number of the indicated technical features. Therefore, the features limited by "first", "second" can explicitly or implicitly include at least one of the features. In addition, the meaning of "and / or" appearing throughout the text includes three parallel schemes. For example, "A and / or B" includes A scheme, or B scheme, or A and B scheme. In addition, the technical solutions of each embodiment can be combined with each other, but it must be based on the realization of ordinary skilled in the art, when the combination of technical solutions appears contradictory or unachievable, it should be considered that the combination of technical solutions does not exist, nor within the scope of protection claimed by the present application.

[0026] Embodiments

[0027] Reference Figs. 1-3 The embodiment provides a nitrogen purging device for a cryogenic pump, which comprises a support table 110 used for placing a cryogenic pump 120, a nitrogen supply device 130 arranged on the support table 110, a gas pipe 140 connected to the nitrogen supply device 130, a nitrogen purging ring 150 connected to the gas pipe 140, the nitrogen purging ring 150 movably sleeving a driving end seal part of the cryogenic pump 120, the nitrogen purging ring 150 being used for blowing nitrogen to the driving end seal part of the cryogenic pump 120, and a swing mechanism 160 arranged on the support table 110 and used for driving the nitrogen purging ring 150 to reciprocatingly rotate at a corresponding amplitude.

[0028] In the embodiment, when the cryogenic pump 120 is temporarily not needed to be used, the cryogenic pump 120 is placed on the support table 110, and then the nitrogen purging ring 150 is sleeved and installed at the driving end seal part of the cryogenic pump 120. The nitrogen supply device 130 is started to supply nitrogen, so that the driving end seal part of the cryogenic pump 120 is purged by nitrogen through the nitrogen purging ring 150. Under the action of the swing mechanism 160, the nitrogen purging ring 150 can be driven to reciprocate at a corresponding amplitude, so that the gas port of the nitrogen purging ring 150 reciprocates around the driving end seal part of the cryogenic pump 120, thereby forming a swing purging, so that the purging area is increased, the purging sufficiency is improved, and the risk of icing of the seal part of the cryogenic pump 120 is reduced. It should be noted that the nitrogen supply device 130 is a nitrogen storage tank with an automatic valve, which is a prior art and will not be described here.

[0029] As an optional implementation, the swing mechanism 160 includes an arc-shaped rack 161 arranged at the bottom of the nitrogen purging ring 150, the arc-shaped rack 161 is engaged with a straight rack 162, the straight rack 162 is slidingly arranged on the support table 110, and the support table 110 is provided with a driving mechanism 170 for driving the straight rack 162 to reciprocate.

[0030] In the embodiment, during operation, the driving mechanism 170 drives the straight rack 162 to reciprocate, and under the action of the gear engagement structure, the arc-shaped rack 161 is driven to reciprocate, so as to drive the nitrogen purging ring 150 to reciprocate, which is a clever structure design and meets the use requirements.

[0031] As an optional implementation, the top of the support table 110 is provided with a guide sliding groove 111 matched with the straight rack 162, and the driving mechanism 170 includes a driving motor 171 arranged at the top of the support table 110, a driving-connected output shaft movably extending into the guide sliding groove 111 and connected with a cam 172, the cam 172 is used to contact one side wall of the straight rack 162, the other side wall of the straight rack 162 is connected with a compression spring 180, and the other end of the compression spring 180 is connected to the corresponding wall of the guide sliding groove 111.

[0032] In the embodiment, during operation, the driving motor 171 drives the cam 172 to rotate, and utilizes the eccentric structure of the cam 172. When the excentric end of the cam 172 contacts the side wall of the straight rack 162, the straight rack 162 is pushed to press the compression spring 180. When the endocentric end of the cam 172 contacts the side wall of the straight rack 162, the straight rack 162 is pushed to move towards the cam 172 under the elastic reset action of the compression spring 180, so as to realize the automatic reciprocation of the straight rack 162.

[0033] As an optional implementation, the nitrogen purging ring 150 is provided with an annular air cavity 151, the outer wall of the nitrogen purging ring 150 is provided with an access port 152 communicating with the annular air cavity 151, the access port 152 is connected with the air pipe 140, and the outer wall of the nitrogen purging ring 150 is provided with a plurality of air outlets 153 communicating with the annular air cavity 151, and the plurality of air outlets 153 are arranged in an annular array.

[0034] In the embodiment, when the nitrogen enters the annular air cavity 151 of the nitrogen purging ring 150 and is discharged through the plurality of air outlets 153, the low-temperature pump 120 seal part is uniformly purged, but due to the size structure limitation of the air outlet 153 (the aperture is not too large, and the number is not too many), the purging area of each air outlet 153 is limited, and therefore the above-mentioned swing purging structure is adopted.

[0035] As an optional implementation, the inner diameter of the air outlet 153 gradually decreases away from the annular air cavity 151, which can improve the air pressure of the nitrogen discharged by the air outlet 153, thereby improving the purging effect.

[0036] As an optional implementation, the support table 110 is provided with a support seat 190, the support seat 190 is height-adjustable, the top of the support seat 190 is provided with an arc clamping plate 210, the arc clamping plate 210 is used for clamping the low-temperature pump 120, and the two side walls of the arc clamping plate 210 are threadedly connected with a plurality of fastening screws 220 used for abutting against the low-temperature pump 120.

[0037] In the embodiment, when the low-temperature pump 120 is installed on the support table 110, the low-temperature pump 120 is first placed on the arc clamping plate 210, and the low-temperature pump 120 is clamped and fixed through the two side fastening screws 220, then the nitrogen purging ring 150 provided with the arc gear rack 161 is installed and sleeved on the driving end seal part of the low-temperature pump 120, since the size specifications of the low-temperature pump 120 can be different, the height of the support seat 190 can be adjusted at this time, that is, the installation height of the low-temperature pump 120 is adjusted, until the arc gear rack 161 can be meshed and connected with the straight gear rack 162 below, thereby improving the universality.

[0038] As an optional implementation, the support table 110 is provided with an accommodating cavity 112, the support seat 190 includes a first wedge block 191 slidingly arranged on the bottom of the accommodating cavity 112, a second wedge block 192 is slidingly arranged on the top surface of the first wedge block 191, and the surfaces of the first wedge block 191 and the second wedge block 192 in contact with each other are both inclined surfaces, the second wedge block 192 is movably penetrated through the top of the support table 110, the arc clamping plate 210 is arranged on the top of the second wedge block 192, and one side wall of the first wedge block 191 is connected with a push-pull piece 230, and the push-pull piece 230 is used to drive the first wedge block 191 to slide.

[0039] In the embodiment, when the installation height of the cryogenic pump 120 needs to be adjusted, the first wedge 191 is driven to slide leftward or rightward by the push-pull piece 230, and the second wedge 192 is correspondingly moved downward or upward under the action of gravity, so as to realize the adjustment of the installation height of the cryogenic pump 120, which is convenient and fast and can facilitate fine adjustment.

[0040] It should be noted that the top of the support table 110 should be provided with a guide limiting groove matched with the second wedge 192, the guide limiting groove being communicated with the accommodating cavity 112, so that the second wedge 192 can only move upward and downward.

[0041] As an optional embodiment, the push-pull piece 230 comprises a movable bearing 231 arranged on the side wall of the first wedge 191, the movable bearing 231 being connected with a rotating handle 232, the rotating handle 232 penetrating the side wall of the support table 110, and the rotating handle 232 being provided with a threaded segment matched with the side wall of the support table 110 in a threaded manner.

[0042] In the embodiment, when the adjustment is performed, the rotating handle 232 can be directly manually operated to rotate, the threaded segment on the rotating handle 232 is screwed into or out of the accommodating cavity 112, and the movable bearing 231 can be matched with the rotation, so as to play a pushing and pulling role on the first wedge 191, and the rotating handle 232 cannot rotate under the action of no external force by utilizing the threaded self-locking effect, so as to ensure that the first wedge 191 does not slide after the adjustment.

[0043] It should be noted that if the vibration environment exists, a locking mechanism can be additionally arranged to fix the position of the adjusted rotating handle 232 to prevent the rotation, and the locking mechanism can adopt a locking piece such as a bolt.

[0044] The above is only the preferred embodiment of the application, and does not limit the patent scope of the application, and any equivalent structure or equivalent process transformation by using the content of the specification and the drawings, or direct or indirect application in other related technical fields, are also included in the patent protection scope of the application.

Claims

1. A nitrogen purge device for a cryogenic pump, characterized by, The system includes a support platform for placing the cryogenic pump, a nitrogen supply device connected to a gas pipe, a nitrogen purging ring movably fitted onto the mechanical seal of the drive end of the cryogenic pump, and a swing mechanism for driving the nitrogen purging ring to reciprocate at a corresponding amplitude.

2. A nitrogen purge device for a cryopump as defined in claim 1, characterized in that, The oscillating mechanism includes an arc-shaped rack located at the bottom of the nitrogen purge ring, which meshes with a straight rack. The straight rack is slidably mounted on a support platform, and a drive mechanism is provided on the support platform to drive the straight rack to reciprocate.

3. A nitrogen purge device for a cryopump as defined in claim 2, characterized in that, The top of the support platform is provided with a guide groove that cooperates with the rack. The drive mechanism includes a drive motor located on the top of the support platform. The output shaft of the drive motor extends movably into the guide groove and is connected to a cam. The cam is used to contact one side wall of the rack. The other side wall of the rack is connected to a compression spring. The other end of the compression spring is connected to the corresponding side wall of the guide groove.

4. A nitrogen purge device for a cryogenic pump as claimed in any one of claims 1 to 3, characterised in that, The nitrogen purging ring has an annular gas chamber inside, and the outer wall of the nitrogen purging ring has an inlet that communicates with the annular gas chamber. The inlet is connected to a gas pipe. The outer wall of the nitrogen purging ring has multiple gas outlets that communicate with the annular gas chamber. The multiple gas outlets are distributed in a ring array.

5. A nitrogen purge device for a cryopump as defined in claim 4, characterized in that, The inner diameter of the air outlet gradually decreases in the direction away from the annular air chamber.

6. A nitrogen purge device for a cryopump as defined in claim 1, wherein A support base is provided on the support platform. The height of the support base is adjustable. An arc-shaped clamping plate is provided on the top of the support base. The arc-shaped clamping plate is used to clamp the cryogenic pump. Several fastening screws for tightening the cryogenic pump are threaded on both sides of the arc-shaped clamping plate.

7. A nitrogen purge device for a cryopump as defined in claim 6, characterized in that The support platform has a receiving cavity. The support base includes a first wedge block that is slidably disposed at the bottom of the receiving cavity. A second wedge block is slidably disposed on the top surface of the first wedge block. The surfaces of the first and second wedge blocks that are in contact with each other are both inclined surfaces. The second wedge block moves through the top of the support platform. An arc-shaped clamping plate is disposed on the top of the second wedge block. A push-pull member is connected to one side wall of the first wedge block. The push-pull member is used to drive the first wedge block to slide.

8. A nitrogen purge device for a cryopump as defined in claim 7, characterized in that The push-pull component includes a movable bearing disposed on the side wall of the first wedge block, the movable bearing being connected to a rotating handle, the rotating handle passing through the side wall of the support platform, and the rotating handle being provided with a threaded section that engages with the threaded side wall of the support platform.

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