CN204226640U - For the seal arrangement of High Temperature High Pressure rotating machinery - Google Patents

For the seal arrangement of High Temperature High Pressure rotating machinery Download PDF

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Publication number
CN204226640U
CN204226640U CN201420464871.4U CN201420464871U CN204226640U CN 204226640 U CN204226640 U CN 204226640U CN 201420464871 U CN201420464871 U CN 201420464871U CN 204226640 U CN204226640 U CN 204226640U
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China
Prior art keywords
seal
unit
face
temperature
pressure
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Withdrawn - After Issue
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CN201420464871.4U
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Chinese (zh)
Inventor
张有华
王威
伍娜
朱晓波
任俊明
周昌奎
侯晓东
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SICHUAN SUNNY SEAL CO Ltd
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SICHUAN SUNNY SEAL CO Ltd
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Abstract

For the seal arrangement of High Temperature High Pressure rotating machinery, the end face seal unit be made up of the rotating seal ring that can rotate with running shaft and the stationary seal ring be connected with base stand location arranged in the running shaft end through high-temperature high-pressure medium district.Wherein in the side, direction, high-temperature high-pressure medium district of the first end face sealing unit be made up of the first rotating seal ring and the first stationary seal ring, be disposed adjacent by being made up of throttling unit and being communicated with the first end face sealing unit Seal cage with high-temperature high-pressure medium district respectively and being provided with the depressor area be communicated with peripheral hardware low voltage unit simultaneously; The Seal cage of the first end face sealing unit is provided with the down cycles passage with heat exchange structure.Sealing device by the high-temperature high-pressure medium of conveying being carried out respectively lower the temperature, step-down, thus the reliable sealing that can adapt to high-temperature high-pressure medium, long service life, Security is high, and the zero leakage of high-temperature high-pressure medium can be realized, the rotating machinery that can be widely used under oil, chemical industry, nuclear power, military industry field high-end devices high temperature and high pressure condition seals.

Description

For the seal arrangement of High Temperature High Pressure rotating machinery
Technical field
The utility model relates to a kind of mechanical seal device for rotary dynamic seal, is applicable to the rotary dynamic seal under High Temperature High Pressure complex conditions.
Background technique
The rotation axis seal of current solution high temperature media operating mode, usually adopt the wavy metal seal of tube, tolerable temperature can reach 450 DEG C, but the pressure that simultaneously can bear is then limited, is the highlyest withstand voltagely also no more than 6MPa.For the rotation axis seal of high-pressure medium operating mode, can adopt spring type mechanical sealing, the highest proof pressure can reach 15MPa at present, but spring sealing configuration is because being subject to the restriction of wherein rubber parts, and its tolerable temperature is generally no more than 300 DEG C.
When temperature more than 300 DEG C, pressure more than 6MPa, the sealing of running shaft is the previous very scabrous problem of order.Due to the restriction by sealing technique, cause the application limiting relevant high parameter machinery equipment.For petrochemical industry, for adapting to energy-saving and emission-reduction requirement, usually need adopt and the hydrofining technology of oil product is refined, improve oil quality, reduce the content of the harmful substance such as sulphur, nitrogen in oil product.Such as, one of key equipment in diesel oil Continuous Liquid Phase hydrogenation technique is High Temperature High Pressure recycle pump, and its typical condition parameter comprises: medium: diesel oil; Pressure: 10.5 MPa; Temperature: 410 DEG C; Leakage rate performance requirement is: inner seal≤20ml/h, outer side seal≤5ml/h; Minimum working life: 8000h.For this kind of high temperature and high pressure condition, Fig. 1 is the current unlubricated seal arrangement of a kind of High Temperature High Pressure, what adopt is the superimposed use of resistant to elevated temperatures graphite packing (15), compressed by gland (18), graphite packing is flattened, outside diameter becomes large, and diameter of bore diminishes, and fills up Seal cage and realizes sealing.Inject the nitrogen also higher than material pressure from suction port, stop material from leakage, take away the heat of part seal friction simultaneously.This structure is embraced very tight because of packing (15) and axle (13), and axle rotates need overcome friction, loss air horsepower.Frictional heating is large simultaneously, and nitrogen fully can not take away heat.Due to high temperature friction effect, make axle be easy to grind away, seal inoperative after grinding gap, in equipment runs, repeatedly must tighten the screw (19) on gland (18), difficult in maintenance.Therefore, sealing structure is still a kind of packing seal essentially, because working life is short, power loss is large, frequency of maintenance is high, is thus only applicable to the high-temperature high-pressure apparatus that rotating speed is low, requirement in working life is not long.
Model utility content
For above-mentioned situation, the utility model provides a kind of seal arrangement being applicable to High Temperature High Pressure rotating machinery.
The utility model is used for the seal arrangement of High Temperature High Pressure rotating machinery, and the same end face seal unit be made up of the rotating seal ring that can rotate with running shaft in the running shaft end setting through high-temperature high-pressure medium district and the stationary seal ring be connected with base stand location that adopts realizes.Its basic structure comprises:
---in the side, direction, high-temperature high-pressure medium district of the first end face sealing unit be made up of the first rotating seal ring and the first stationary seal ring, be disposed adjacent by the depressor area be made up of a pair throttling unit along the static arrangement of new ro-tational axis, depressor area is communicated with the first end face sealing unit Seal cage with high-temperature high-pressure medium district by this two throttling unit simultaneously respectively, and with the pressure ports be communicated with the low voltage unit of peripheral hardware, the low-voltage equipment unit such as the closed low pressure head tank of its prime generally can be connected to;
---the Seal cage of the first end face sealing unit is provided with the down cycles passage with heat exchange structure.
On the basis of above-mentioned basic structure, for ensureing and improve safety, the reliability of sealing further, in the axially outside of the first end face sealing unit, preferably also be provided with the second end face seal unit be made up of the second rotating seal ring and the second stationary seal ring, and sealing fluid circulation canal is provided with in the Seal cage of the second end face seal unit, be provided with heat exchange unit and liquid storage unit in described sealing liquid circulation canal.
The improved procedure that can also adopt further comprises; in the axially outside of the first described end face sealing unit; or the second axially outside of end face seal unit; there is a seal protection district through spaced 3rd throttling arrangement isolation, in seal protection district, be provided with the cooling passage be communicated with cooling system with insulation blocking.
In the seal arrangement of the above-mentioned form of the utility model, can separately or with the further preferred embodiment adopted that combines with said structure in any way, also can comprise:
At described first end face sealing unit Seal cage with in the circulation temperature lowering passage of heat exchange structure, the fluid infusion passage be connected with the fluid infusion source of bank savings can also be provided with, be conducive in replenishment cycles process because of circulatory mediator liquid that different reason is lost.
Circulation is realized through described circulation temperature lowering passage for making the liquid in described first end face sealing unit Seal cage, except can in a conventional manner except the pumping equipment of this circulation temperature lowering channel setting appropriate format, one of optimal way that can also adopt, being the periphery at the first described rotating seal ring, being provided with the pump efficiency ring for driving the liquid in the first end face sealing unit Seal cage to carry out the conventionally form circulated through described circulation temperature lowering passage.
Adopt above-mentioned be provided with the second described end face seal unit time, in the sealing fluid circulation canal in the second end face seal unit Seal cage, usually can be provided with pumping equipment or the pumping unit of current common type, promote sealing fluid circulate.
In the seal arrangement that the utility model is above-mentioned, described the first end face sealing unit be made up of the first rotating seal ring and the first stationary seal ring is the primary seal unit realizing High Temperature High Pressure mechanical rotary seal.Due to the side, direction in its high-temperature high-pressure medium district, through being disposed adjacent a depressor area along a pair throttling unit of the static arrangement of new ro-tational axis, and can be communicated with the first end face sealing unit Seal cage with high-temperature high-pressure medium district respectively by this two throttling unit simultaneously, and also with the pressure ports be communicated with peripheral hardware low voltage unit, therefore high-temperature high-pressure medium can enter the Seal cage of this depressor area and the first end face sealing unit, but by the effect of throttling unit, then the pressure medium entering depressor area can be made to fall lower.By arranging equipment and the control valves such as corresponding pressure sensing, detection in pressure ports, can realize carrying out monitor and forecast to the pressure in depressor area.The reduction of pressure medium in depressor area, also reduces the pressure medium in the first end face sealing unit Seal cage simultaneously.Produce because the medium in depressor area has a large amount of vaporizer when only reducing pressure, enter Seal cage for avoiding vapour to have an impact to end face seal, by the down cycles passage with heat exchange structure that arranges in the Seal cage of the first end face sealing unit and corresponding fluid infusion passage, inject appropriate liquid and (be preferably the material identical with pumped medium, avoid polluting pumped medium), and make pressure in Seal cage suitably higher than the pressure of depressor area, vapour can be stoped to enter in the Seal cage of the first end face sealing unit, also the temperature reducing circulating liquid is conducive to, and provide required lubricant medium to sealing end face.
Because this first end face sealing unit is the primary seal unit sealed the medium material respectively after cooling, step-down process, cooling then cannot be realized when pump shaft non rotating, it is still hot environment in its Seal cage, therefore the sealing in this first end face sealing unit, can adopt as current normally used high temperature resistant sealing structures such as the wavy metal seals of tube.
Be appreciated that thus, the seal arrangement of the utility model said structure form, by the high-temperature high-pressure medium material that routine and sealing configuration/element are directly contacted, after first having carried out step-down and cooling process respectively, enter Seal cage again to contact with sealing configuration/element, thus make it can bear completely and reliably realize the medium material after to step-down, cooling process to seal.
Described second end face seal unit in the above-mentioned seal arrangement of the utility model, at the security seal unit as setting further on the first end face sealing unit basis of primary seal, object and effect are when primary seal is damaged, the second that institute's pumping material carries out is stopped, to avoid high-temperature high-pressure medium in abnormal cases to the leakage of atmosphere environment.The high pressure spring sealing that sealing in second end face seal unit can adopt reliability high usually.Wherein, the band temperature reducing unit arranged in the Seal cage of the second end face seal unit and the sealing fluid circulation canal of liquid storage unit; can by equipment such as the recycle pumps of current common type; the sealing fluid in outside liquid storage unit is allowed to participate in circulation; and provide one lower than the steady pressure of the first end face Seal cage to Seal cage; to take away the fricative heat of its seal face; Lubricants can be provided to the second end face seal unit simultaneously; the pressure reduction of the first end face sealing unit both sides as primary seal can also be reduced, protection primary seal.
The seal protection district that can be communicated with cooling system with the insulation blocking of independent peripheral hardware through cooling passage also arranged further in the outside of the second end face seal unit, on the basis of said structure, can provide further safe and reliable guarantee to sealing.Such as; low-pressure water, steam or nitrogen etc. can be provided by described insulation blocking and cooling system; by cooling passage realize further isolating oxygen, Leakage prevention oils coking, wash away leakage, reduce temperature outside security seal, the second end face seal unit is protected.
The seal arrangement that the utility model is above-mentioned, by respectively to high temperature, high-pressure medium material takes step-down, the measures such as cooling and fluid infusion, not only improve the operating mode operating conditions at end face seal position, and the combination that the two-stage passing through the second end face seal unit arranged seals, adapt to satisfactorily and solve achieve reliable sealing to high-temperature high-pressure medium, there is long service life and the high advantage of Security, the zero leakage of high-temperature high-pressure medium can be realized, oil can be widely used in, chemical industry, nuclear power, rotating machinery under military industry field high-end devices high temperature and high pressure condition seals.
Below in conjunction with the embodiment of accompanying drawing illustrated embodiment, foregoing of the present utility model is described in further detail again.But this should be interpreted as that the scope of the above-mentioned theme of the utility model is only limitted to following example.Do not departing from the above-mentioned technological thought situation of the utility model, the various replacement made according to ordinary skill knowledge and customary means or change, all should be included in scope of the present utility model.
Accompanying drawing explanation
Fig. 1 is the structural representation of the current unlubricated seal arrangement of a kind of High Temperature High Pressure.
Fig. 2 is the structural principle schematic diagram of the utility model for the seal arrangement of High Temperature High Pressure rotating machinery.
Fig. 3 is the schematic diagram of a kind of concrete structure of the first and second end face seal unit in the utility model seal arrangement.
Embodiment
As shown in Figure 2, the utility model is used for the seal arrangement of High Temperature High Pressure rotating machinery, include in running shaft 13 end of crossing high-temperature high-pressure medium district 14, two groups that are disposed adjacent the successively end face seal unit be made up of the rotating seal ring that can rotate with running shaft and the stationary seal ring be connected with base stand location.Wherein:
---in the side, direction, high-temperature high-pressure medium district of the first end face sealing unit (i.e. primary seal unit) of the wavy metal seal of tube be made up of the first rotating seal ring 9 and the first stationary seal ring 91, be disposed adjacent the depressor area 61 be made up of a pair throttling unit 6,7 along the static arrangement in running shaft 13 interval.This depressor area 61 is by this two throttling unit 6,7 can be communicated with the first end face sealing unit Seal cage 71 with high-temperature high-pressure medium district 14 simultaneously respectively, this depressor area 61 is simultaneously also with the pressure ports 1 be communicated with the low voltage unit of peripheral hardware, in pressure ports 1, also according to actual conditions and needs, suitable valve and pressure monitoring devices can be set.
---the Seal cage 71 of the first end face sealing unit is provided with heat exchange unit 21(as all kinds of conventional dividing wall type heat exchanger etc.) down cycles passage 2, temperature, the pressure checking device of appropriate format also can be set in passage according to actual needs.In this circulation temperature lowering passage 2 with heat exchange structure 21, also can be provided with the fluid infusion passage 3 be connected with the fluid infusion source of bank savings (medium identical with institute conveying material can be adopted).For the liquid promoted in Seal cage 71 circulates through this circulation temperature lowering passage 2, the periphery of this first rotating seal ring 9 can be provided with the pump efficiency ring 11 of appropriate format.
---in the outside of the first end face sealing unit, be disposed adjacent the second end face seal unit (i.e. security seal unit) sealed by the high pressure spring be made up of the second rotating seal ring 10 and the second stationary seal ring 101.Its Seal cage 12 is also provided with sealing liquid circulation canal 4, and in sealing liquid circulation canal 4, be provided with temperature reducing unit 41(as all kinds of conventional dividing wall type heat exchanger etc.) with as the conventional liquid storage unit 42 of the forms such as liquid container, and for the pumping equipment that promotes liquid-circulating or unit 43.
In the axially outside of above-mentioned second end face seal unit (i.e. security seal unit), also isolate through spaced 3rd throttling arrangement 8 and have a seal protection district 81, in seal protection district 81, be provided with the cooling passage 5 be communicated with cooling system with insulation blocking.
Fig. 2 is a sealing device structure (structure of main presentation first and second end face seal unit) that typically can be used for diesel oil liquid-phase hydrogenatin main circulating pump.Be 400 DEG C of conveying, 10MPa and the High Temperature High Pressure diesel oil of sulfide hydrogen and molten hydrogen in High Temperature High Pressure district, it is by throttling unit 6 and enter depressor area 61, draws a part to extraneous low pressure diesel tank field by the pressure ports 1 controlled by pressure regulator valve.Through throttling unit 6 and pressure ports, can by the Pressure Drop in depressor area 61 to 2.6MPa, part diesel oil, molten hydrogen, hydrogen sulfide also will exist in depressor area with gaseous state simultaneously.
By extracted out by raw oil pump 120 DEG C, that the diesel oil of 3MPa separates aliquot is not shown in fluid infusion passage 3(way) and temperature adjustment passage 2 inject face, main side Seal cage 71 endlessly, because its pressure is higher than the pressure of pressure letdown chamber, the diesel oil of injection blocks gaseous component and enters Seal cage.The liquid of Seal cage is by temperature adjustment passage 2, pump efficiency ring 11 and thermosyphon effect, constantly enter temperature adjustment passage 2 and cool through heat exchange structure 21 and circulate, make Seal cage liquid stabilising at 260 DEG C, below 3MPa, for mechanical seal provides a good running environment.
Security seal unit is had in primary seal unit arranged outside.The diesel oil of the sealing liquid circulation canal 4 in security seal unit Seal cage separate with raw oil pump 120 DEG C, 3MPa, by reduction valve by the Pressure Drop of Seal cage 12 to 0.8Mpa, for security seal provides Lubricants, take away the heat that seal friction produces simultaneously, then stay back conventional liquid storage unit 42.
Primary seal unit, if any a small amount of leakage, can enter in the lump in the sealing liquid circulation canal 4 of security seal unit, can not enter in air.When primary seal lost efficacy, security seal can continue to work, and simultaneously the pressure of its Seal cage raises, and spread out of alarm signal, notice parking maintenance equipment by sensing equipments such as the pressure transmitters that arranges in sealing liquid circulation canal 4.

Claims (7)

1. for the seal arrangement of High Temperature High Pressure rotating machinery, the end face seal unit that be made up of the rotating seal ring that can rotate with running shaft and the stationary seal ring be connected with base stand location that running shaft (13) end be included in through high-temperature high-pressure medium district (14) is arranged, is characterized in that:
---in the side, direction, high-temperature high-pressure medium district of the first end face sealing unit be made up of the first rotating seal ring (9) and the first stationary seal ring (91), be disposed adjacent by a pair throttling unit (6 along the static arrangement in running shaft (13) interval, 7) depressor area (61) formed, depressor area (61) is by this two throttling unit (6,7) be communicated with the first end face sealing unit Seal cage (71) with high-temperature high-pressure medium district (14) respectively simultaneously, and with the pressure ports (1) be communicated with the low voltage unit of peripheral hardware;
---the Seal cage (71) of the first end face sealing unit is provided with the down cycles passage (2) with heat exchange structure (21).
2. seal arrangement as claimed in claim 1, it is characterized in that the axially outside at the first end face sealing unit, be provided with the second end face seal unit be made up of the second rotating seal ring (10) and the second stationary seal ring (101), the Seal cage (12) of the second end face seal unit is provided with sealing fluid circulation canal (4), and in sealing fluid circulation canal (4), is provided with heat exchange unit (41) and liquid storage unit (42).
3. seal arrangement as claimed in claim 1; it is characterized in that the axially outside at the first end face sealing unit; there is a seal protection district (81) through spaced 3rd throttling arrangement (8) isolation, in seal protection district (81), be provided with the cooling passage (5) be communicated with cooling system with insulation blocking.
4. seal arrangement as claimed in claim 2; it is characterized in that the axially outside at the second end face seal unit; there is a seal protection district (81) through spaced 3rd throttling arrangement (8) isolation, in seal protection district (81), be provided with the cooling passage (5) be communicated with cooling system with insulation blocking.
5. the seal arrangement as described in one of Claims 1-4, it is characterized in that at described first end face sealing unit Seal cage (71) with in the circulation temperature lowering passage (2) of heat exchange structure (21), be provided with the fluid infusion passage (3) be connected with the fluid infusion source of bank savings.
6. the seal arrangement as described in one of Claims 1-4, it is characterized in that the periphery of the first rotating seal ring (9) in described first end face sealing unit, being provided with for driving the liquid in the first end face sealing unit Seal cage (71) to carry out the pump efficiency ring (11) circulated through described circulation temperature lowering passage (2).
7. the seal arrangement as described in claim 2 or 4, is characterized in that being provided with pumping unit (43) in described sealing fluid circulation canal (4) in the second end face seal unit Seal cage (12).
CN201420464871.4U 2014-08-18 2014-08-18 For the seal arrangement of High Temperature High Pressure rotating machinery Withdrawn - After Issue CN204226640U (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201420464871.4U CN204226640U (en) 2014-08-18 2014-08-18 For the seal arrangement of High Temperature High Pressure rotating machinery

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Application Number Priority Date Filing Date Title
CN201420464871.4U CN204226640U (en) 2014-08-18 2014-08-18 For the seal arrangement of High Temperature High Pressure rotating machinery

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104895825A (en) * 2014-10-15 2015-09-09 邢宇 A shaft sleeve for cooling a double mechanical seal friction pair and a centrifugal pump cooling system having the same
CN105351521A (en) * 2014-08-18 2016-02-24 四川日机密封件股份有限公司 Sealing device for high-temperature and high-pressure rotating machinery
CN106838331A (en) * 2017-03-30 2017-06-13 四川高博环保工程有限公司 Agitating shaft gas blowing seal structure in a kind of tank for sludge hydrolytic processing equipment
CN110307337A (en) * 2019-07-09 2019-10-08 中国航发哈尔滨东安发动机有限公司 A kind of rubber sealing structure having refrigerating function

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105351521A (en) * 2014-08-18 2016-02-24 四川日机密封件股份有限公司 Sealing device for high-temperature and high-pressure rotating machinery
CN104895825A (en) * 2014-10-15 2015-09-09 邢宇 A shaft sleeve for cooling a double mechanical seal friction pair and a centrifugal pump cooling system having the same
CN104895825B (en) * 2014-10-15 2017-12-22 邢宇 The axle sleeve and its centrifugal pump cooling system for cooling down double mechanical seal friction pair
CN106838331A (en) * 2017-03-30 2017-06-13 四川高博环保工程有限公司 Agitating shaft gas blowing seal structure in a kind of tank for sludge hydrolytic processing equipment
CN110307337A (en) * 2019-07-09 2019-10-08 中国航发哈尔滨东安发动机有限公司 A kind of rubber sealing structure having refrigerating function

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C14 Grant of patent or utility model
GR01 Patent grant
AV01 Patent right actively abandoned
AV01 Patent right actively abandoned

Granted publication date: 20150325

Effective date of abandoning: 20171003