CN204692588U - The gas lubrication mechanical seal device that a kind of closing force is adjustable online - Google Patents
The gas lubrication mechanical seal device that a kind of closing force is adjustable online Download PDFInfo
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- CN204692588U CN204692588U CN201520344626.4U CN201520344626U CN204692588U CN 204692588 U CN204692588 U CN 204692588U CN 201520344626 U CN201520344626 U CN 201520344626U CN 204692588 U CN204692588 U CN 204692588U
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- 238000005461 lubrication Methods 0.000 title claims abstract description 16
- 230000033001 locomotion Effects 0.000 claims description 9
- 239000012530 fluid Substances 0.000 claims description 4
- 230000001105 regulatory effect Effects 0.000 abstract description 6
- 238000007789 sealing Methods 0.000 description 18
- 230000003068 static effect Effects 0.000 description 5
- 230000001276 controlling effect Effects 0.000 description 3
- 230000006835 compression Effects 0.000 description 2
- 238000007906 compression Methods 0.000 description 2
- 230000002153 concerted effect Effects 0.000 description 2
- 230000007812 deficiency Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000001050 lubricating effect Effects 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
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Abstract
The gas lubrication mechanical seal device that a kind of closing force is adjustable online, comprise rotating ring axially locating ring, end cover, rotating seat, piston, working spring, piston limit ring, throw-out collar, stationary ring, rotating ring and seal chamber, described rotating ring to be fixed on rotating seat and to rotate with axle, and described stationary ring is installed on end cover; Piston cavity is provided with in described end cover; Described end cover offers outer air supply channel, and communicates with the piston cavity of piston side; Be provided with working spring between the opposite side of piston and stationary ring, described piston moves axially along piston cavity the decrement changing working spring; The opposite side of piston is exposed in seal chamber, and seal chamber is communicated with cushion gas passage.By regulating the decrement of the adjustable working spring of outer supply gas pressure, and then realize the on-line control to seal closure power.
Description
Technical field
The utility model relates to a kind of shaft end seal of rotating machinery, is specifically related to the gas lubrication mechanical seal that a kind of seal closure power is adjustable online, can be used for the shaft end seal of the high speed rotating machineries such as various compressor, blower fan and centrifugal pump.
Background technique
Gas lubrication non-contact mechanical seal (also known as " dry gas seals ") because of its friction power loss low, stable and reliable for performance, auxiliary system is simple, the significant performance advantage such as long service life, and obtains extensive use on the high speed rotating machineries such as centrifugal compressor, blower fan, centrifugal pump.Dry gas seals by offering the fluid sound die mould groove of various shape on seal face, when rotating ring rotates, utilize the active and static pressure effect of type groove gas medium to be pumped into seal face produce certain opening force and push end face open, form the air film of one deck micron order thickness between two seal faces and keep non-contact to run.But when sealing startup and stopping, because between two seal faces, relative rotation speed is lower, be not enough to produce enough hydrodynamics, may cause seal face that direct contact wear occurs.Dry Gas Seal can cause seal face temperature rise too high in this contact friction wearing and tearing in start and stop stage, or makes end face scratch and affect sealability; And in the high speed operation phase, the hydrodynamic pressure produced due to Hydrodynamic pressure type groove is remarkable, two seal faces may be pushed open and form excessive seal clearance, cause the leakage of sealing medium to exceed standard.Can open rapidly in open stage for making Dry Gas Seal, and the air film of one deck 3 ~ 5 μm can be maintained and keep lower leakage between high speed stable operation stage end face, realize by the method in different operation phase on-line control closing forces or opening force.
Chinese patent CN101776152A proposes a kind of outside pressurized type dynamic and static pressure gas lubricating and sealing device, passage and the throttle orifice that can introduce compressed gas from the external world is offered in stationary seal ring, balancing slit is offered at stationary ring end face, increase active and static pressure opening force in the sealing start and stop stage to being filled with the cushion gas of certain pressure between seal face, thus realize the quick unlatching of seal face.The control to opening force size between seal face can be realized by the pressure of adjustment cushion gas, but this structure needs the cushion gas (pressure is higher than the pressure 0.15 ~ 0.45MPa of sealed medium) of elevated pressures, therefore need a set of comparatively complicated outer air supply source, make auxiliary system become complicated, and the control accuracy of external air supply source pressure require higher.Chinese patent CN104179975A proposes a kind of controllable type mechanical seal based on changing closing force, its principle be curent change by controlling electromagnetic loading device to realize the ACTIVE CONTROL to sealing, but this structure needs a set of electromagnetic loading device and assistant regulating and controlling system thereof.Patent CN102128272A proposes the controlled mechanical seal device of a kind of closing force, by forming the regulatable labyrinth seal of leakage rate at stationary ring outside diameter hoop and comb ring, utilizes the throttle effect of labyrinth seal to realize changing the object of closing force.
Existing technological scheme is by the regulation and control to mechanical seal opening force or closing force, to realize the regulation and control to different operation phase seal face contact condition, but still there is external regulator control system and the monitoring system of Structure of need complexity, be unfavorable for applying in high speed rotating machinery dry gas seals.
Summary of the invention
The utility model will overcome the seal face start and stop stage existed in dry gas seals prior art and easily come in contact fretting wear, and it is excessive and cause leakage and exceed standard at high speed operation phase end face thickness, closing force cannot realize the deficiency of online regulation and control, and in existing unseal power or closing force controlling technology scheme regulator control system or sealing configuration comparatively complicated, be unfavorable for deficiencies such as applying in rotating machinery dry gas seals, a kind of structure is proposed simple, the gas lubrication mechanical seal device that seal closure power is adjustable online.
The technical solution of the utility model is:
The gas lubrication mechanical seal device that a kind of closing force is adjustable online, comprise rotating ring axially locating ring 1, end cover 2, rotating seat 3, piston 4, working spring 7, piston limit ring 8, throw-out collar 9, stationary ring 10, rotating ring 11 and seal chamber 12, described rotating ring 11 to be fixed on rotating seat 3 and to rotate with axle, and described stationary ring 10 is installed on end cover 2; It is characterized in that:
Piston cavity 15 is provided with in described end cover 2; Described end cover 2 offers outer air supply channel 14, and communicates with the piston cavity 15 of piston 4 side; Be provided with working spring 7 between the opposite side of piston 4 and stationary ring 10, described piston 4 moves axially along piston cavity 15 decrement changing working spring 7; The opposite side of piston 4 is exposed in seal chamber 12, and seal chamber 12 is communicated with cushion gas passage 16.
Further, between the internal face of described piston 4 and piston cavity wall, be provided with the first auxiliary seal ring, between the outer wall of described piston 4 and piston cavity wall, be provided with the second auxiliary seal ring; The end face contacted with working spring 7 of described piston 4 is provided with mounting hole or the mounting groove of working spring 7, and described stationary ring 10 is connected with working spring 7 by throw-out collar 9.
Further, the inwall of described piston cavity 15 is provided with the limited step of piston 4, for the shift motion of the side of working spring dorsad of limited piston 4; Piston limit ring is fixed on end cover, for the shift motion of limited piston towards working spring side.
Further, described outer air supply channel 14 is communicated with outer supply air line, described cushion gas passage 16 and cushion gas pipeline connection, be provided with the first pressure regulator valve 13, be provided with the second pressure regulator valve 17 between described cushion gas pipeline and source of the gas between described outer supply air line and source of the gas.
Further, described working spring 7 is circumferential equally distributed little spring, described little spring number be 6 ~ 30.
Or described working spring 7 is big spring.
Further again, in described rotating ring 11 or stationary ring 10, at least one seal face is provided with fluid. dynamic pressure groove.
Form closed piston cavity between described piston and end cover, described piston can move axially along piston cavity the decrement changing working spring, described end cover offers outer air feed gas-entered passageway, and communicates with piston cavity.By regulating the decrement of the adjustable working spring of outer supply gas pressure, and then realize the on-line control to seal closure power.
The inwall of described piston cavity is provided with the limited step of piston, and when described piston movement contacts to piston left side with limited step, described working spring has minimum amount of spring compression, and now spring pressure selection range is 0.005MPa ~ 0.009MPa.
Described piston limit ring is fixed on end cover, for the shift motion of limited piston to working spring side, when described piston moves to piston right side and piston limit loop contacts, described working spring has maximum decrement, and now spring pressure selection range is 0.013MPa ~ 0.020MPa.
Outer air supply channel on described end cover is communicated with outer supply air line, cushion gas passage on described seal chamber and cushion gas pipeline connection, be provided with pressure regulator valve between described outer supply air line and source of the gas, between described cushion gas pipeline and source of the gas, be provided with pressure regulator valve.
For general dry gas sealing structure, the active length of spring is difficult to regulate in running, therefore sealing can only stable operation near operating point for design, the start and stop stage then easy because of face opening power not enough, or closing force is excessive and cause opening difficulty.The fitting seat of working spring is designed to the piston structure that can move axially by the utility model, moves axially the decrement that can change working spring by piston in piston cavity, reaches the object regulating closing force.By between piston inner wall face and piston cavity wall, and between piston outer wall face and piston cavity wall, auxiliary seal ring is installed, thus constructs a closed piston cavity.When sealing is in static pressure state or start and stop stage, regulate the pressure regulator valve between outer supply air line and source of the gas, when closed piston chamber China and foreign countries, air feed pressure medium is less than p
1time, outer air feed pressure medium is less than making a concerted effort of sealed medium pressure and working spring power, piston left side contacts with piston cavity limited step, working spring is in minimal compression, now closing force is less, seal face can be opened rapidly, but the minimum spring pressure of working spring should be not less than 0.005MPa, to ensure the parking sealer with no pressure of dry gas seals; When sealing is in the high speed operation phase, regulate the pressure regulator valve between outer supply air line and source of the gas, when closed piston chamber China and foreign countries, air feed pressure medium is greater than p
2time, outer air feed pressure medium is greater than making a concerted effort of sealed medium pressure and working spring power, piston right side and piston limit loop contacts, working spring is in most compressed state, spring pressure is now the working spring specific pressure designed by given operating point, to ensure that seal face air film gap is in suitable scope, avoids the leakage rate of sealing medium excessive.
The gas lubrication mechanical seal device that the utility model provides a kind of closing force adjustable online, compared with prior art, its beneficial effect is:
(1) in the dry gas seals start and stop stage, by the outer air feed pressure medium of on-line control to reduce working spring decrement, thus reduce seal closure power, seal face is opened fast, avoid direct contact friction and the wearing and tearing of start and stop stage seal face, improve working life and the reliability of sealing.
(2) in dry gas seals high speed stable operation stage, by increasing outer air feed pressure medium online to increase working spring decrement, thus increase seal closure power, to ensure that seal face can maintain the stable operation of one deck 3 ~ 5 μm of thickness air films, and keep lower leak-down rate, improve sealing.
(3) closing force on-line control structure is simple, without the need to changing the structure of moving sealing ring or stationary ring, being all easy to realize, can being applicable to very wide rotating speed and pressure working condition scope in laboratory and engineer applied scene.
Accompanying drawing explanation
Fig. 1 is the sealing configuration sectional view of a kind of embodiment of the present utility model;
Fig. 2 be in the utility model piston movement to sealing configuration sectional view during stroke high order end;
Fig. 3 be in the utility model piston movement to sealing configuration sectional view during stroke low order end;
Fig. 4 is the force analysis figure of piston in the utility model;
Fig. 5 is the force analysis figure of stationary ring in the utility model;
Fig. 6 is that in the utility model, working spring is the sealing configuration sectional view of big spring;
Embodiment
Below in conjunction with embodiment shown in the drawings, the utility model content is described in further detail.
Embodiment one
With reference to Fig. 1, Fig. 2, Fig. 3, Fig. 4 and Fig. 5:
The gas lubrication mechanical seal device that a kind of closing force is adjustable online, comprise rotating ring axially locating ring 1, end cover 2, rotating seat 3, piston 4, working spring 7, piston limit ring 8, throw-out collar 9, stationary ring 10, rotating ring 11 and seal chamber 12, described rotating ring 11 to be fixed on rotating seat 3 and to rotate with axle, and described stationary ring 10 is installed on end cover 2; Piston cavity 15 is provided with in described end cover 2; Described end cover 2 offers outer air supply channel 14, and communicates with the piston cavity 15 of piston 4 side; Be provided with working spring 7 between the opposite side of piston 4 and stationary ring 10, described piston 4 moves axially along piston cavity 15 decrement changing working spring 7; The opposite side of piston 4 is exposed in seal chamber 12, and seal chamber 12 is communicated with cushion gas passage 16.
By regulating the decrement of the adjustable working spring 7 of outer supply gas pressure, and then realize the on-line control to seal closure power.
Be provided with the first auxiliary seal ring 6 between the internal face of described piston 4 and piston cavity wall, between the outer wall of described piston 4 and piston cavity wall, be provided with the second auxiliary seal ring 5; The end face contacted with working spring 7 of described piston 4 is provided with mounting hole or the mounting groove of working spring 7, and described stationary ring 10 is connected with working spring 7 by throw-out collar 9.
When dry gas seals is in static pressure state or start and stop stage, piston is generally in position as shown in Figure 2, the inwall of described piston cavity 15 is provided with the limited step of piston 4, when described piston 4 move to piston left side contact with limited step time, described working spring 7 is in minimum compressive state, and now spring pressure is not less than 0.005MPa.
When dry gas seals is in the high speed operation phase, piston is generally in position as shown in Figure 3, described piston limit ring 8 is fixed on end cover 2, for the shift motion of limited piston to working spring side, when described piston 4 move to piston right side contact with piston limit ring 8 time, described working spring 7 has maximum decrement.
Described working spring 7 is circumferential equally distributed little spring, and the preferred value scope of described little spring number is 6 ~ 30.
Outer air supply channel 14 on described end cover 2 is communicated with outer supply air line, cushion gas passage 16 on described seal chamber and cushion gas pipeline connection, be provided with the first pressure regulator valve 13 between described outer supply air line and source of the gas, between described cushion gas pipeline and source of the gas, be provided with the second pressure regulator valve 17.
Described stationary ring 10 end face is provided with fluid dynamic pressure groove.
Described piston 4 as shown in Figure 4 stressed, the left side of described piston 4 is subject to outer air feed pressure medium, right side is subject to working spring power and cushion gas pressure medium, by regulating pressure regulator valve 13, the adjustment to piston cavity 15 China and foreign countries air feed pressure medium can be realized, thus the outer air feed pressure medium changed suffered by piston 4 left side, and then change the decrement of working spring 7, also namely change the spring force of working spring 7.
Described stationary ring 10 as shown in Figure 5 stressed, closing force suffered by described stationary ring 10 comprises working spring power and cushion gas pressure medium, and when working spring power changes, seal closure power changes, and then the air-film thickness between change seal face, thus realize the regulation and control to seal face contact condition.
Embodiment two
With reference to Fig. 1,2,3,4,6, the difference of the present embodiment and embodiment one is that described working spring 7 is big spring, and all the other structures are identical with embodiment one with mode of execution.
Content described in this specification embodiment is only enumerating the way of realization that model utility is conceived; protection domain of the present utility model should not be regarded as being only limitted to the concrete form that embodiment states, protection domain of the present utility model is also and in those skilled in the art according to the thinkable equivalent technologies means of the utility model design.
Claims (7)
1. the gas lubrication mechanical seal device that a closing force is adjustable online, comprise rotating ring axially locating ring (1), end cover (2), rotating seat (3), piston (4), working spring (7), piston limit ring (8), throw-out collar (9), stationary ring (10), rotating ring (11) and seal chamber (12), described rotating ring (11) is fixed on rotating seat (3) and goes up and rotate with axle, and described stationary ring (10) is installed on end cover (2); It is characterized in that:
Piston cavity (15) is provided with in described end cover (2); Described end cover (2) offers outer air supply channel (14), and communicate with the piston cavity (15) of piston (4) side; Be provided with working spring (7) between the opposite side of piston (4) and stationary ring (10), described piston (4) moves axially along piston cavity (15) decrement changing working spring (7); The opposite side of piston (4) is exposed in seal chamber (12), and seal chamber (12) is communicated with cushion gas passage (16).
2. the gas lubrication mechanical seal device that a kind of closing force as claimed in claim 1 is adjustable online, is characterized in that:
Be provided with the first auxiliary seal ring between the internal face of described piston (4) and piston cavity wall, between the outer wall of described piston (4) and piston cavity wall, be provided with the second auxiliary seal ring; The end face contacted with working spring (7) of described piston (4) is provided with mounting hole or the mounting groove of working spring (7), and described stationary ring (10) is connected with working spring (7) by throw-out collar (9).
3. the gas lubrication mechanical seal device that a kind of closing force as claimed in claim 2 is adjustable online, is characterized in that:
The inwall of described piston cavity (15) is provided with the limited step of piston (4), for the shift motion of the side of working spring dorsad of limited piston (4); Piston limit ring is fixed on end cover, for the shift motion of limited piston towards working spring side.
4. the gas lubrication mechanical seal device that a kind of closing force as claimed in claim 3 is adjustable online, is characterized in that:
Described outer air supply channel (14) is communicated with outer supply air line, described cushion gas passage (16) and cushion gas pipeline connection, be provided with the first pressure regulator valve (13) between described outer supply air line and source of the gas, between described cushion gas pipeline and source of the gas, be provided with the second pressure regulator valve (17).
5. the gas lubrication mechanical seal device that a kind of closing force as claimed in claim 4 is adjustable online, is characterized in that:
Described working spring (7) is circumferential equally distributed little spring, described little spring number be 6 ~ 30.
6. the gas lubrication mechanical seal device that a kind of closing force as claimed in claim 4 is adjustable online, is characterized in that: described working spring (7) is big spring.
7. the gas lubrication mechanical seal device that a kind of closing force as described in one of claim 1-6 is adjustable online, is characterized in that: in described rotating ring (11) or stationary ring (10), at least one seal face is provided with fluid dynamic pressure groove.
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Cited By (8)
Publication number | Priority date | Publication date | Assignee | Title |
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CN104896104A (en) * | 2015-05-25 | 2015-09-09 | 浙江工业大学 | Online adjustable closing force gas lubricating mechanical sealing device |
CN106545523A (en) * | 2016-10-28 | 2017-03-29 | 沈阳透平机械股份有限公司 | Prevent the end cover structure and processing method of vertical subdivision compressor operating gas leakage |
CN109648706A (en) * | 2019-01-28 | 2019-04-19 | 河南三和水工机械有限公司 | It is a kind of with can on-line control lubricating arrangement environment-friendly dry blended mortar mixer |
CN110259397A (en) * | 2019-05-30 | 2019-09-20 | 北京石油机械有限公司 | A kind of mechanical sealing washing pipe assembly |
CN110425129A (en) * | 2019-06-21 | 2019-11-08 | 中国计量大学上虞高等研究院有限公司 | A kind of low leakage double acting symmetrical expression fluid flow precision metering device |
CN110425103A (en) * | 2019-06-21 | 2019-11-08 | 中国计量大学上虞高等研究院有限公司 | A kind of two D supercharging equipment of sludge and sealing mechanism |
CN110439780A (en) * | 2019-06-21 | 2019-11-12 | 中国计量大学上虞高等研究院有限公司 | One kind zero reveals interior self-powered rotary piston fluid conveying device |
CN110594415A (en) * | 2019-09-05 | 2019-12-20 | 山东正铭流体控制设备有限公司 | Increase dry gas seal of life-span |
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2015
- 2015-05-25 CN CN201520344626.4U patent/CN204692588U/en active Active
Cited By (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN104896104A (en) * | 2015-05-25 | 2015-09-09 | 浙江工业大学 | Online adjustable closing force gas lubricating mechanical sealing device |
CN106545523A (en) * | 2016-10-28 | 2017-03-29 | 沈阳透平机械股份有限公司 | Prevent the end cover structure and processing method of vertical subdivision compressor operating gas leakage |
CN109648706A (en) * | 2019-01-28 | 2019-04-19 | 河南三和水工机械有限公司 | It is a kind of with can on-line control lubricating arrangement environment-friendly dry blended mortar mixer |
CN110259397A (en) * | 2019-05-30 | 2019-09-20 | 北京石油机械有限公司 | A kind of mechanical sealing washing pipe assembly |
CN110259397B (en) * | 2019-05-30 | 2023-09-29 | 北京石油机械有限公司 | Novel mechanical seal flushing pipe assembly |
CN110425129A (en) * | 2019-06-21 | 2019-11-08 | 中国计量大学上虞高等研究院有限公司 | A kind of low leakage double acting symmetrical expression fluid flow precision metering device |
CN110425103A (en) * | 2019-06-21 | 2019-11-08 | 中国计量大学上虞高等研究院有限公司 | A kind of two D supercharging equipment of sludge and sealing mechanism |
CN110439780A (en) * | 2019-06-21 | 2019-11-12 | 中国计量大学上虞高等研究院有限公司 | One kind zero reveals interior self-powered rotary piston fluid conveying device |
CN110425129B (en) * | 2019-06-21 | 2020-12-29 | 中国计量大学上虞高等研究院有限公司 | Low-leakage double-acting symmetric fluid flow precision metering device |
CN110594415A (en) * | 2019-09-05 | 2019-12-20 | 山东正铭流体控制设备有限公司 | Increase dry gas seal of life-span |
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