Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16J—PISTONS; CYLINDERS; SEALINGS
  • F16J15/00—Sealings
  • F16J15/16—Sealings between relatively-moving surfaces
  • F16J15/34—Sealings between relatively-moving surfaces with slip-ring pressed against a more or less radial face on one member
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
  • F01D11/00—Preventing or minimising internal leakage of working-fluid, e.g. between stages
  • F01D11/003—Preventing or minimising internal leakage of working-fluid, e.g. between stages by packing rings; Mechanical seals
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16J—PISTONS; CYLINDERS; SEALINGS
  • F16J15/00—Sealings
  • F16J15/002—Sealings comprising at least two sealings in succession
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16J—PISTONS; CYLINDERS; SEALINGS
  • F16J15/00—Sealings
  • F16J15/16—Sealings between relatively-moving surfaces
  • F16J15/34—Sealings between relatively-moving surfaces with slip-ring pressed against a more or less radial face on one member
  • F16J15/3404—Sealings between relatively-moving surfaces with slip-ring pressed against a more or less radial face on one member and characterised by parts or details relating to lubrication, cooling or venting of the seal
  • F16J15/3408—Sealings between relatively-moving surfaces with slip-ring pressed against a more or less radial face on one member and characterised by parts or details relating to lubrication, cooling or venting of the seal at least one ring having an uneven slipping surface
  • F16J15/3412—Sealings between relatively-moving surfaces with slip-ring pressed against a more or less radial face on one member and characterised by parts or details relating to lubrication, cooling or venting of the seal at least one ring having an uneven slipping surface with cavities
  • F16J15/342—Sealings between relatively-moving surfaces with slip-ring pressed against a more or less radial face on one member and characterised by parts or details relating to lubrication, cooling or venting of the seal at least one ring having an uneven slipping surface with cavities with means for feeding fluid directly to the face
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16J—PISTONS; CYLINDERS; SEALINGS
  • F16J15/00—Sealings
  • F16J15/16—Sealings between relatively-moving surfaces
  • F16J15/34—Sealings between relatively-moving surfaces with slip-ring pressed against a more or less radial face on one member
  • F16J15/3464—Mounting of the seal
  • F16J15/348—Pre-assembled seals, e.g. cartridge seals
  • F16J15/3484—Tandem seals
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16J—PISTONS; CYLINDERS; SEALINGS
  • F16J15/00—Sealings
  • F16J15/44—Free-space packings
  • F16J15/447—Labyrinth packings

Definitions

• the invention relates to a shaft seal for sealing a gap of a passage of a shaft through a housing, wherein inside the housing a process fluid under ei ⁇ nem sealing pressure and outside the housing is an ambient fluid under an ambient pressure, the shaft seal at least two sealing modules, at least one fluid supply and at least one fluid discharge, wherein the sealing modules comprise at least a first main seal and an inner secondary seal, wherein the first
• Main seal as a radial gas seal, with a rotating sealing surface and a stationary sealing surface is filedbil ⁇ det, said sealing surfaces are opposite in a sealing plane, wherein the sealing plane has a substantially radial extent to the shaft, wherein the standing sealing surface and rotating sealing surface on a Carrier, Namely ⁇ a stationary support and a rotating support, are fixed, and the sealing surfaces, elastically braced against each other by either at least the stationary support or the rotating support is biased by an elastic element.
• the invention also relates to an arrangement with a shaft seal of the aforementioned type and a method for operating a fluid energy machine, in particular a turbo-compressor with a shaft seal of the type defined.
• Shaft seals of the aforementioned type are frequently used, in particular, on turbomachines which have a shaft which has been produced from the housing and which makes it possible to connect a drive or a drive. It is in the nature of the wave ⁇ seal that due to the relative movement of the shaft surface to the adjacent housing is not one hundred percent Tightness can be achieved. Particularly in the case of toxic or explosive process fluids which are to be kept away from the environment by means of the shaft seal, the leakages must be carefully deduced. Also, for example, in steam or gas turbines, the process fluid is hindered by ei ⁇ ner such shaft seal to leak into the environment and the leakage of the shaft seal or the quantum of the suction has a direct impact on the resulting thermal efficiency. Minimizing the leakage of a shaft seal is one of the most important tasks in the design of such machines.
• tandem gas seals In centrifugal compressors often assume gas seals, in particular so-called tandem gas seals, the task of the pressure chamber within said housing to the atmospherelockeddich ⁇ th.
• the tandem gas seals are non-contacting seals and belong to the dry gas seals. These are lubricated with dry filtered barrier fluid or barrier gas to prevent soiling and humidification that impair the function.
• the invention relates to gas seals always dry gas seals.
• Labyrinth seal known.
• the sealing gas is taken from the pressure side or a pressure stage of the fluid energy machine or the compaction ⁇ ter, dried, filtered and fed to thekowskigasdich- device.
• a pressure gradient of the sealing gas is taken from the pressure side or a pressure stage of the fluid energy machine or the compaction ⁇ ter, dried, filtered and fed to thekowskigasdich- device.
• a ⁇ set a seal gas booster This is a compressor of the gas from the compressor sucks in pressure increases thereby ensuring that he ⁇ ford variable pressure gradient to the barrier gas supply.
• the invention has therefore taken on the task to improve the An ⁇ order with the shaft seal of the type mentioned in such a way that the need for additional sealing fluid decreases without resulting in losses in terms of tightness and safety of operation and oh ⁇ ne that an additional compressor is necessary.
• this directional indication refers to an increasing or decreasing proximity to the interior of the housing or the exterior of the housing.
• the pressure sink at the first labyrinth seal can be further improved by an additional second labyrinth seal for pressure reduction, so that even less sealing gas is required.
• gas gas from the compressor and sealing gas
• gas can preferably be discharged via a pipe and a control valve into a low pressure disposal system.
• the control valve is preferably controlled by a control that regulates a differential pressure between the pressure in the compressor and the pressure in the pressure sink.
• Disposal system is derived with low pressure. This simpler option does not regulate the differential pressure as precisely as the solution with the control valve is costly. cheaper. Construction tolerances in the maze columns can affect the pressure in the pressure sink so that the regulation system ⁇ according to the requirements of Automatverdichtungsprozes- ses and its boundary conditions must be defined accordingly.
• the outflowing gas generates by the resulting pressure losses in the first
• Labyrinth seal a pressure sink. Due to this pressure drop, the differential pressure between pressure in the compressor and pressure in the pressure sink, which is required for drying and filtering of the sealing gas in a barrier gas system is produced. During the pressure relief of the compressor by Ab ⁇ let the gas within the compressor is thus ensured ⁇ that due to the pressure sink sufficient sealing gas supply of the dry gas seal takes place.
• the compressor can be expanded up to a pressure at which another external sealing gas supply is possible again or is expanded to atmospheric pressure without any further supply of external blocking gas.
• the shaft seal according to the invention is formed as a ne radial double seal, which is ⁇ be true by two gas seals, each with a ro ⁇ tierenden sealing surface and a stationary sealing surface, wel ⁇ ches sealing surface pair is in each case opposite in a sealing plane, wherein the two sealing planes have a substantially radial extent to the shaft, wherein a first sealing surface pair of the two sealing surface pairs is located on a larger radius than the second sealing surface pair and wherein standing sealing surfaces and rotating sealing surfaces of the two sealing surface pairs are each attached to a common carrier, namely a stationary support and a rotating support, and the sealing surfaces of the Dichtflä ⁇ chenpare are elastically braced against each other by ent ⁇ wede at least the stationary support or the rotating support ger is biased by means of an elastic element, wherein between the two sealing surface pairs extending in the circumferential direction barrier fluid chamber is provided, which by
• the sealing surface pairs are preferably arranged coaxially, so that there is a simple and space-saving design.
• the stationary carrier of the gas seal is biased by ei ⁇ nes elastic element in the direction of the rotating carrier. In this way, the centrifugal force ⁇ set construction of the rotor is less complicated Afterbil ⁇ det.
• a preferred operation of the sealing arrangement according to the invention provides that the first main seal is acted upon by process fluid as barrier fluid.
• the second main seal may also be formed as the first main seal ⁇ than a simple dry gas seal.
• the second main seal which is be ⁇ aufschlagt with an intermediate barrier fluid as a barrier fluid.
• the intermediate blocking fluid may be identical to the barrier fluid of the first main seal or another fluid, for example nitrogen.
• an additional first additional shaft seal preferably a labyrinth shaft seal is arranged. In this way it is ensured that no leaks of the first main ⁇ seal MSI get into the second derivative via the second main seal.
• the first barrier fluid drain is arranged on the inward side of this additional shaft seal between the two main seals.
• An advantageous development of the invention provides that a supply of an intermediate blocking fluid is provided between the second main seal and this aforementioned additional shaft seal.
• Main seal additionally two shaft seals, preferred
• Labyrinth shaft seals are arranged one behind the other, an inner fourth additional shaft seal and an outer fifth additional shaft seal.
• the partitioning becomes particularly effective if a supply line of a separation fluid is provided between these two additional shaft seals.
• This separation fluid may be filtered ambient medium.
• Such an arrangement is particularly interesting when the outside of the entire seal assembly, for example, an oil storage is provided, could escape from the leaking oil mist in the seal assemblies and would lead to possibly dangerous fluid mixtures.
• the supplied separation fluid can be conveniently derived between the second main seal and the two successively arranged fourth and fifth additional shaft seals by means of a second derivative.
• the discharges can be supplied to a combustion in a common flare.
• the externally required amount of barrier fluid is greatly ver ⁇ reduces, as compared to conventional arrangement, the required pressure level of the barrier fluid is lowered.
• it can be dispensed with a pressure increase of the barrier fluid, since the pressure sink according to the invention or the Sperrfluid- suction lowers the pressure level in the first main seal or in the main seals. Due Oblivion the pressure increases, the internal circular amounts be reduced to be compressed and the volumetric fluid We ⁇ ciency, for example, of a compressor improves.
• FIG. 1 shows a schematic representation of the shaft seal and arrangement according to the invention for operation by the method according to the invention.
• Figure 2 is an exemplary illustration of a radial
• FIG. 1 shows an inventive embodiment of an arrangement of a shaft S and a rotor R, a housing C and a shaft seal of a turbo compressor SSS TCO to collectively ⁇ more sealing modules SM.
• FIG. 1 shows also schematically a flowchart with different fluid streams and signal lines of a control CU.
• the arrows below the sealing modules SM respectively indicate the flow direction which is established in the interior when the compressor is at a standstill and, accordingly, lowered.
• the turbocompressor can be blocked by means of two valves, an inlet valve SVI and an outlet valve SVE, that is, the inflow and outflow line can be shut off.
• the sealing modules are arranged essentially mirror-symmetrically to an interior of the turbocompressor TCO and, because of the identity to the other side, in some cases not all individually designated.
• the sealing modules SM include - starting from the interior of the housing C.
• a first main seal MSI designed as a radial simple gas seal or as a radial double seal according to FIG. 2,
• a second main seal MS2 designed as a radial simple gas seal or as a radial double seal according to Figure 2 and
• Process Fluids PF Between the first labyrinth seal LTS1 and the second labyrinth seal LTS2 there is a barrier fluid suction SLF.
• the first main seal MSI is lubricated with barrier fluid SF supplied inwardly of the first main seal MSI.
• the second main seal MS2 is lubricated with interstitial fluid ISF supplied to the second main seal MSI, for example, nitrogen.
• sealing fluid SF is zessfluid in the form of purified product PF supplied with an overpressure, so that an outflow yields both inwardly of and in away by the two sealing surface pairs SSP of the radia ⁇ len double seal.
• the second main seal can be operated as a radial double seal.
• first main seal MSI and the second main seal MS2 there is a first derivative EX1 derived the from the first main seal MSI outwardly flowing process zessfluid PF and a partial amount of optionally present Zvi ⁇ rule barrier fluid ISF.
• first derivative EX1 derived the from the first main seal MSI outwardly flowing process zessfluid PF and a partial amount of optionally present Zvi ⁇ rule barrier fluid ISF.
• the space between the first main seal MSI and the second main seal MS2 a positive pressure to the degraded through the second main seal MS2, which is preferably embodied as a simple gas seal, white ⁇ ter becomes.
• a second derivative EX2 which discharges a mixture of intermediate barrier fluid and ISF fluid that comes from the away team following Dichtungskombina ⁇ tion.
• the surroundings AF are under an ambient pressure PAM.
• a separation fluid SPPF is supplied, which escapes in both directions and should prevent any contamination from the outside at the entrance to the arrangement.
• the separation fluid SPPF is either the n costume medium of the environment or an inert fluid, ⁇ example, be nitrogen.
• Labyrinth seal is formed, located between the two main seals MSI, MS2.
• the first derivative EX1 is located in this third additional one
• the intermediate blocking fluid ISF for example nitrogen, is introduced. This ensures that no barrier fluid SF of the first main seal MSI can reach the second main seal MS2 and can be discharged as leakage in the outlet EX2.
• the shaft seals of the turbocompressor TCO shown in FIG. 1 are supplied with barrier fluid SF from a barrier fluid system SFSY.
• the Sperrfluid- system SFSY obtained by means of a bleed line PFSF from the outlet of the turbocompressor TCO process fluid under a entspre ⁇ accordingly high discharge pressure, which is filtered and optionally gerei ⁇ nigt and dried so that it is the shaft seal as a barrier fluid SF available.
• the blocking fluid system SFSY can be supplied with external blocking fluid EXT by means of a line. This supply is used to seal the machine even in operating conditions in which no barrier fluid SF without the external barrier fluid EXT can be made available, for example as a result of too low pressure in the other barrier fluid system SFSY or other adversities.
• a central control unit CU detects the pressure difference in the barrier fluid system SFSY to the outlet of the compressor TCO.
• the pressure difference ⁇ between the outlet of the compressor TCO and the Sperrfluidabsaugung SLF is determined by means of a pressure measuring point PPSLF.
• the central control unit CU opens or closes a barrier fluid suction control valve CVSLF, by means of which the pressure level is externally adjusted to the internal secondary seals SS2.
• the Sperrfluidabsaugungsregelvertil CVSLF is opened in such a way that adjusts the supply of the barrier fluid SF inward of the first main seal MSI a lower pressure level than in the barrier fluid system SFSY, so that the inflow of the barrier fluid SF in the
• Gap G is ensured for the separation and, if necessary, lubrication of the first main seal MSI.
• the barrier fluid suction SLF leads into a pressure sink FL whose pressure level is always sufficiently low, so that there are no conflicts with the barrier fluid system SFSY with regard to insufficient pressure difference for supplying the barrier fluid SF.
• a pressure curve with the pressures at different axial positions is shown in the illustration.
• a first pressure curve PLB1 shows the pressure level in the blocked-in compressor TCO directly after a switch-off and a second pressure curve PLB2 shows the pressure level in the blocked-in compressor after the expansion.
• the pressure level of the second pressure profile PLB2 results in ⁇ We sentlichen by the supplied sealing gas SF.
• FIG. 2 shows a schematic representation of a radial double seal RDS, which seals a gap G between a shaft S and a rotor R and a housing C.
• the shaft S is provided with a circumferential shoulder SC, which carries a rotating part of the radial double seal RDS.
• the radial double seal essentially consists of two radially arranged one behind another gas seals DGSL, DGS2 each having a rotating sealing surface RSS and a stationary sealing surface SSS arising corresponding to two Dichtflä ⁇ chenzipe SSP.
• DGSL radially arranged one behind another gas seals
• DGS2 each having a rotating sealing surface RSS and a stationary sealing surface SSS arising corresponding to two Dichtflä ⁇ chenzipe SSP.
• a locking fluid is supplied into a located there, located in the circumferential direction extending chamber SFC which up respectively of the two sealing ⁇ surface pairs SSP escape due to the overpressure between the rotating sealing surface RSS and the stationary sealing surface SSS.
• the rotating sealing surfaces RSS and the stationary sealing surfaces SSS of the two sealing surface pairs SSP are firmly connected to each other by means of a common carrier RSUP, SSUP.
• the stationary carrier SSUP is biased by means of an elastic element EEL against the rotating carrier RSUP.

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• Engineering & Computer Science (AREA)
• General Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Structures Of Non-Positive Displacement Pumps (AREA)
• Sealing Using Fluids, Sealing Without Contact, And Removal Of Oil (AREA)

Applications Claiming Priority (2)

Publications (1)

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Family Applications (1)

Country Status (5)

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• 2014
  • 2014-09-19 DE DE102014218937.3A patent/DE102014218937A1/de not_active Withdrawn
• 2015
  • 2015-09-08 WO PCT/EP2015/070465 patent/WO2016041814A1/de active Application Filing
  • 2015-09-08 EP EP15763538.4A patent/EP3161357A1/de not_active Withdrawn
  • 2015-09-08 RU RU2017108794A patent/RU2657403C1/ru not_active IP Right Cessation
  • 2015-09-08 CN CN201580050742.8A patent/CN106687663B/zh not_active Expired - Fee Related

Non-Patent Citations (1)

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