HUE027666T2 - Sealing system for centrifugal pumps - Google Patents

Description

»» SYSTEM FOR CENTRIFU€AL PUMPS tTescripttou p0Oii| Use invention concerns a sealing arthagemsstt te mainlaimag fes smallest gaps between rotor and easing: of a hqmdWfetivmng íkád vs^:«dfe^r^>esM%«.ôëâtn&g*î pump. |0ÖP| ín fiáid m>ik machines, ülte leakage flow Through gaps between rotating and smdonáfy parts with diííerent présures upstream Md downstream Sássá tits gap* constitute a sfgmicam loss factor, iSwcfe gaps are used at vmms places is Sold work machines. They thlghT fee the places râr : mstaliamm «if split rings, mm rings, piston aod&sr dtskmhaped relief devices, step seals In the tsedthmugh area of shall wheels -mdfar rotors m parts thereof Since the sire of such: gap greatly of"ö|«; stashlhes,. esne etide;rvoers w keep the«» as narrow and long as possible, is order ig avoid an excessive leakage Sow. Many variants are known in «he literature for: the sealing of such gaps and their configuration. The mimnmm gap which cap be achieved in such designs is limited, since one idust always allow for mana&chnmg and tolerances to enable a umbility between the parts. A low -friction relative movement xn the area of such a seeing gap is of advantage, especially for the rotor a®d ihr the casing. PEH&t It is known fenn EF ! 305 156 B1 how t© masatam clo^rf^pcds^pp seals Id The aiha of tir® seal. When using plastic as sealing material in a water pump, however, there: is tfee drawback that the plastic will swell up under the action of the water and result in a narrowing of the sealing diameter. This incr eases the friction between seal and rotor, whieh increases the power eonsiunphon of the: pomp, is osier to decrease the power Toss of a pump «mit its the region of the gap seal, an additional saififening elementis ppposed for the gap seafe which is surronnded at feast in putt by a sealing matériái. The materials of the sitting sfenent and the sealing material are chosen sash: that at least owe scaling dimension of the gap seal remaps essendaMy cesstMi under the action of a fluid, fm ids, the shrinkage or swelling of the one material coanTerfeaiaaeesfte shrinkage or swelling of the other msterihí in the desired direction, so that an essentially constant dimension of the seal should be achieved. This ref aires the use of materials lor stlffehihg element and: sealing matcrM^ which swell up íhllhmatly uhdsf The mtluenee of the Said. The siiihssses of sealing material and: stifiening material should he aitiStcd to each other so that even an ioereasiitg of the diameter of the stihemsg ring due the three produced fey the swelling of the sealing gtgferial is compensated and the sealing dimension remains constant, P0fc*i Front US 4913S19 A there Is known a device of this kind fm a ceramic seal in a pump, In which the two sealing components are pmss fitted in the casing. f(M)05f From EP 0 4ÜÖ 261 Bl there is known a multiple-past guiding device transporting a Sow for centrl&gai pumps, whose parts alternately lie against a fitting site thanks to the use of différent: «natenals in dependence on The particular UMperature. This prevents a striking of the puatp shafi: against: bearing Ideations or seal bashings and a comaet between stationary and rotaiing p««rts. P§§dJ EP 2 S4§ 096 AI shows a nmitiple-part sealing arrangement -hat is placed between a wall of the pump casing sod the impels* of a cetärÄgaf pomp and seals It plf into a shelf shaped section. la this kind of spit ring seal, additional complex parts have: to he hell mhe- impeller and easing, which involves considerable expose and restîSts In larger size of structurai parts and laager volume. pSÖ2| OB 10 20ÖE 001 814 Ai likewise shews a ven’ complex multiple-part impeller seal la a centrifugal pump, consisting of a rigid pressure ring and an elastic sealing ring, la eperathm of the centrifugal pomp»·, the sea&g; ring thrusts against a siding surface to provide a seal, while the sliding; ring is hissed agamst the sliding surface, The drawback here is that És biasing has to he precisely adin^I of else the imiter sealing result will contest the cost of no increased irierioHsl power. p§S8| The problem which the hwenitea proposes to solve is to create a device Sir controlling the gap width between rotor and easing of a fcid work machine., Is particular a cenbirugal pomp* guiding liquid and/or steam, which enables m automatic adlusting of the gap width without enlatgh^ liie structural; part; and which can also be used as a replacement for existing gap seals. Ρ@θ$1 13» solution calls lor a device made of a composite material for csoiroimg the gap width between rotor and casing of a Hold work Machine, io particular a centrifugal pump, wherein: at least a first material component of the composite materiál is designed as a fern-giving stabilization composent and a second matedai composes! of the composite material is designed as a swelling npierial producing usddr the Miluence of moisture a change hi volume, and wherein at: leapt One gsp-limiting wall surface of the device can be spatially altered by means of the swelling Material, |8dl0| A detdee according to the invention, especially a spitting, swells up upon first contact with the delivered fluid until the gap hetween rotor and casing: & mlnhnieed. lire dnsensions of a new, nonswellen spit ring are: less than required far operation, this affords the advantage,: when installing the new split ring, that it is easy to monoti Its operation, the split f ihg part made from swelling material swells up due to contact with she irassported fluid, $o that it takes oh the optinsal dlsmnsions for the operation and minimizes the gap hounded by the device. The device according to hi® invention consists of at least two ehrest material components, wherein at least one irst material competent predefines the geometric hson of the device .and one second material component Is designed as a swelling Mmerial with gap: widM-ehangiog properties. Advantageously, the swelling material is arranged ip the eornposde material over the entire sorfáé« of the latter,, in layers, pomts and/or segmeMs. Thus, a precise changing of the gap can occur for a design model and/or a loading condition. The pointlike and/or segmented arrangement in the composite material also include the so-called gradient materials or graded stracturai parts made from them. Their texture design enables an adapting m arpsi&g of Ésse -w»lf mimen- which delimit a sealing gap, border us it, or have: an e&eet of changing: it pol l! According io other embodiments, the material components have different swelling behaviour and/or dithregt fluid permeability. It; is likewise possible for the ffest materia! component: to he designed as: a pmtecbvy layer which temporarily or paffkliy rifields the sec opd material component, la this way, a. controlled swelling behaviour cas be achieved. A device used as a gap seal can be installed with minimal tolerances, and the swelling material isi jmsteeied by a shieidipigagainst contact with its 11¾¾¾¾ iffy ohspge id the gap occurs itt thé course of tfrs operating fife* for example doe to wear and testy this will occur1 tat the irsti thsterial component. The swelling process at the second material component will decaf depesidlftg oh Its degree of wear or liquid peàtsæÉdfity. Thus, longer tgtetating tithes with minimal sealing: gaps cap he accomplished without overhauling work interrupting the operation. PÔ12J Ih case advantageous: embodiment, the device consists of a compaslie ovateml, especially a layered cmnppslte material, wherein at least ope of the layers consists of a material which swells npna contact with P hansported hold. The layering makes it possible to Increase the stability of the device. layering thanks to a combination of stabiliring layers and swelling layers makes it possible to redueethe effeet of abrasion. If a non-swelling layer is gradually worn down in the course of the operating life, tire next swelling layer is freed up and swells until the gap is once again reduced to a necessary minimum, Use sepraion of the IhdMpal swelling layers allows for p adapting of the seal as needed to the diifeest opemting cmrdftiops, P0$3f ;|b traditional spit rings, when the rotor strikes against the.split tang the result is a pednapent widening of the gap, and hi Ée worst case a blockage. In the case of the invention, however, only the «pearneable first matetld is damaged, so that the second material freed up in this way once more readjusts the gap thanks to its swelling, |0014| in 'm -Usee ease of altosting; layer position of the composite material, the: layer thickness of the second material increases; toward Ée side away froth the gap. When the split ting is gradually worn down dnring operation, the sealing element will swell ap mots In order to close the Widening gap. This is accomplished If the lap* thickness of the swelling: malaria! increases, fhhlSf The second materia! for me in a sealing arrangemesi according to the invention is a biogenic material, in particular wood or thermally treated wood. This allows the use of a simple and cost-effective materia! which is available !»: large volume and «nth dlierenl Prslerial properties. pNIMj Furthermore, the first material Can be a polymer materia! based oh renewable: raw materials. It is advantageous for the material to hh exactly adjustable to the needs of the gáp aéa! and for the necessary raw materials to he awlsbfe with: almost no limit, f8®f7| ht the use of the device aocordmg io fite ítpepíion, such as a spit ting, ft fe advantageous for the materials used to have dblerept sitopgths with respect to &e mating frlehon partner. Since the split ring is easily biased by the swelling, a friction arising during operation between spit ring and casing or between splft ring and rotor can result in abrasion of material This is dependent on the choice of the material of äse friction. patiner. As a result oftfee abrasion* île spilt-ting is mm ground down, until tse biasing ©Äs ^limg'éisitô swelling no longer results ja friction between the mdlvldual structural paris, In adthtion, one must take Mo acemast te Epical overlook scenarios for te particular application, and the time coarse of the swelling should be optimally adjastcd to tent, |#0J8| The layers áré: tribologically adjusted to the individual case of usually high relative: velocities and different pressing forces nom radial deflection of the rotor, so thaï in event of contact the efficiency is not redoeeti by te friction losses outweighing Ée ;gte írom the sealing effect; p03:Sff fn order to measure the material ahmsfop, id ;anoter «teodtraeföt there is provided a sensor for demoting when te devise is word down. Thaoks to this sensor, if is possible to detect te; ktetent wear on the device. If the device is entirely tent down, an evalumiug device; of the sensor will semi a signal thai te device has to be replaced soon. ffteÖJ la s® especially prefeed embodiment, a molstnre sensor is integrated In te gap at te tetesi removed stvoümg region. which responds to te moisture initiating the swelling and dots indicates that the last Stelling region is being utilized. |ÖÖ3? J For use in rotational fluid work machines, te device is configured as a split ring. Split rings of te most di verse kind are cteteary; te reducing the gap between the rotor and the casing of a laid; work machine. The spilt ring according to te; invention can he designed in its geometry a&d its aterteliMly ®fnsting pfogerdes so that it «as fee retrofitted without problem in already existing fluid vte%tenbtes- f8i22| f artitemote the invention desedfees a. method of eonshueting a device for mtetaihmg the smallest gap width iMweeu rote and casing of a Hold work machte, wherein te matériái pairing of te gap-forming surfaces of device and casing or rotor is chosen such that wear occurs only at te devstej and the at least one Stelling layer of te device is chosen in dependence os the transported fluid so that a sweiing of ins teyàt. hrisgs about art automatic aigastméstof the gap width to a mioteum gap, This and tes a loss teoagh fidetipn and wear of te device are prevented. |8S23] in one embodiment of te meted, the material pairing when designing toe device is chosen such that wear is minimized. The choice of te materials lakes into account difeent teters pfisrdteoee, such as the area of application of the fluid work machine, te transported fluid and te tehsport: ttedÄns stte as pressure and temperature. If ail factors are attuned to each other, it is possible to keep down te wear sat te gap-forming surfaces. |0024| Funher embodiments will emerge from the combination of those presented thus far and therefore are not further mdieted hte.: PS2S] Sample embodimenis of fee Invenfeul m presented iss fee drawings md shall be described more closely below. There are shows fig. 3, a perspective view of a device according tsik& festest«*»

Fig, 2, a section along plane A of Fig. I,

Fig, .3,. a sectionalong plane 8 of fig, 1 for a first sample epfeodlment Fig. 4 a section along plane: B of Fig, ! for a second sample! embodiment,

Fig. 3, a section aloitg plarse B öfl%. 1 f^.i^irdslaillál'i^abQáiíöesd

Fig, 6, a section along plane B of Fig. 3 for a fourth sample em bodiment Fig, % a parte o f fee device of Fig. 2 in sectional view along pksse A of Fig, 1,

Fig. 8, another variant of die device of Fig. 2 in sectioned view along plane A of Fig, 3 and Fig, P, aucsfeer variant of the device of Fig, 2 in sectional view along plane A of Fig. I.

[ßö26| Fig, 1 shows a perspective view of a device according ίο fee invention. The device is configured as so annular gap seal 1, In inis repfesefeatkm, only a first material 2 can be seen, forming the surface of the gap seal 1,. |ÖÖ27J The gap seal I can either be connected on the eater sprite :3 firmly and statically sealing to another structural patt, for example a pump casing, in which case a gap to be sealed is present at the inner surface 4. A noch of hub part of a rbtteg pump impeller, sot shows hete Sír masons of clarity, would he msesíeá loto fee Space enclosed by fee Inner surface 4, Imre shown la tlw form of an anmdar internal clrcunderendai surface. Between these two parts, a sealing gap weald be formed to ensfes fee relative movemem of fee impeller, On fee other hand, fen gap seal 1 can also he firmly connected on the inner surface 4 to a rotating impeller. The sealing gap would then be formed between fee Outer surface 2, in this ease in fee form of an annular rotating outer eimuBferehtlal sdrfeee, and a stationary opening feot: shownl of a puipp casing seal. In order to produce a roiaaooaliy firm connection to the particular structural part, the gap seal I can fee further provided wife grooves, toothings, or ofeer twist prevention designs* ffesse are familiar items and therefore are not otherwise shown in fee present representation. The end face δ lies each time against the structural part holding fee device. Generally speaking, fee surface of the gap seal lasing fee particular gap shall be designated add represented as fee gap wall 7. The sectional planes  and B have been drawn to further explain fee following figures. P$28:| Fig, 2 shows a seetta through the gap seal 1 along section plane A shown to Fig. I, It is clearly sees feat fee overall: device -has; a layered constmction, where one layer of a first material 2 is followed in aiterttafisg fashion by a layer of a second material 5. The ferm-glvfeg first material 2 completely encloses lie layers of fee swelling second material 5, fit a device consiteg of several layers in succession, this prevents these layers vfeieh: consist of the second material 5 from coming into direct contact wife a transported fiaid. This dependably pevents a swelling: ©f fee layers .5, In fee Installed state of the gap sea! t and in an iterative connexion wife a easing andfer an impeller, fee outer surface 3 ond&e the inner surface 4 are exposed to a wear-producing loading, especially in the ease of the pump under stress outside of the design range, such as a partial load or as excess load, in: this way, dartag the course of the ogafolipg period a material abrasion ffom the fust material 2 woekl occur, and the sealfeg. gap feoapitsd fey it tyotil atersase. if this material abrasion eposes the iayer of®« second materM 5, Its swelling polity would then eatssea change m shape of the inner surface 4 and/or eater surface 3·, In the aunaior contlgnratiss àe here, the swelling would result Is a corresponding change lu the diameter, so that the gap-bounding wall surface decreases the seating gap pK&ff Fig. 3 shows & longitudinal section throsgh 1nvÉÉtaâiloKgpîa8« '% M F%,. 1. Äs eueapsulatifeh of the second material 5 m at the order snrfaces of the device: Is tXmty seen In the figure si M, Both the esd faces S and dte gap wall 7 as weil as the side lying opposite it ate made of dp first material 2. Upon wearing of the gap wall % matériái abrasion oceans on this surface bounding the gap* so that a. gap cross section Is Increased, stmtiar to wear. If, thanks to the wear, a gap wall T iodkated by broken lue Isexposed, the swelling second tnstmal 5 is then In direct contact with the dúld being sealed off Ceæsegaendy, the volume of dîe seecmd màtënâi S laemtKseSy thereby forming feere a new gap wall 7” of smaller diameter, as shown in Fig. 3 at right. Tire radiai p^üS:M:^,now"sd^s#}stfe^ gap wad T causes a redaction of the gaps feeing sealed and: reducing the flow passage, which improves the efficiency of a fluid machine, The influence of the shorter gap fcægtb» which Is mmmmltee thanks to -the slightly shorter length or width of the newly formed gup waif ?” with no tnaterial irtásion at the end face, is negligible,

Pdlftl Fig.4 shows a Songi tudlnai section th rough asecond stemple embodiment of the spilt ring according to the invsntkm along plane B of fig, I, The end faces 4 consist of a Sfst materia! % the gap wad 7 emisists of the second materii! S ásd in: the statdihg condition it is not encapsulated in the direction of the gap, Upon first contact with the fluid, a swelling occurs, which narrows the gap. Tfef figure shows two additional layers of the swelling tnaterial 5, which are entirely encapsulated by the first material 2, These áré exposed only upon eonfltming wear sad begin to swell later os, PCKMJ Fig. 5 and Fig.O show longitudinal sections aiong plans B of Fig. ! for two iirthef sample embodiments of the split ripg according to the Invention, la there embodiments: the gap wall T is prövided m. the: axial direction, i,C:,, at one of the end faces 6. The outer surface 2 and the mm surface 4 are firmly joined to the neighbouring structural part. pd331 Use esnbodhnent in fig, S shows a split ring In which the swelling second material $ is cootplefely «sUétipstdaled by the first material 2. Only when the first materia! 2 is worn down by idodpu at the gap wall 7 can fluid penetrate into the second material 5 a cause it to swell thereby further reducing the gap,. ÍSÖ33I Th« embodiment In Fig, 6 is comparable m the split ring shown io fig. Ί, The second matériái 5 at the gap wall 7 is exposed to the fluid from the outset ind can Itphtödíatfeiy begin swelling, which lets its gap be reduced to a minimum. |0I)34] Fig» 7 shows s variant of the device according to the invention in a sectional view m the plane A of Fig. 1, in Which Öté thickness of the swelling layer, consisting of the second material 5, increases. In the figure, at the centre of the ring, is shown the region of the gap wail ? at the inner surface 4 in wh ich the fete makes contact with Été nfefihg: umvable park its file esse of the rotor seal*, die rotor Is arranged here. Thanks to the swelling, the device is pressed against the rotes. See to the resulting fefetion, the device Is gradually worn down. Thu continuing swelling of Éve somsad material 5 closes the gap during the operrimo. When Me first layer of the second material 5 Is completely worn down, an increased swelling is seeded is order to close the enlarged gap. This is nw.de possible by the thicker layer of second material 5. fOi&Sl Fig. $ shows in a sectional view along plane A of Fig. 1 a variant in which the swelling .fejset rtf the second material 5 is arranged in individual segments, These segments are sash time completely eheapMated by the first material 2, ;S0 that each segment can swell sspfatelyi Thanks to Ä: aribugenamL one can specifically compensate for differences in die gap width depehdiflg im lódat wearing rites, without letSng the entire: eírghöíferense of the split ring swell up. In this way, one can prevent die seeosd material Som swelling in areas where it Is again removed at once by abrasion, which might needlessly increase the friction. A segmenting of the second material 5 is also possible in the axial direction, which is not shown in Fig. S tor technical reasons, |0d36|: Another variant of this; segmented arrangement of the second materia! 5 within a closed matrix formed by the first menial 2 Is shown Is: Fig. 9. la the euf-uut detail of Fig, Id, lenses of the second material 5 are shown, having a gradation, Le„ a steady Increase in volume. With increasing abrasion, äü ever iactearing swelling is needed to close the gap. This circumstance is handled by the increasing size of the lenses of the second material. A simtlar arrangement has already been shown in Fig, 7. |0837] The lenses Is Fig, Id are shown in orderly arrangement. Also advisable are split rings in which the lenses of dte second material $ are stafisfieally distributed in the first material. Likewise, the size relations is the example shown she only ekemfdmy, since the swelling lenses can also he: provided as rnwroparticles. The effects made possible fey^Ése gradation can also be ohmised when the lenses ate Is a radially disorderly arrasgement. ptBSl For rimplicity, Ém individual layers are ritpws here in parallel, fleométries are also conceivable in Which idssrieai layers are isierecnmected by spine-ilhe dsfi>nsalioss. This aeltieves as increased stability or a specific, swelling in the entire device. One can also use split ring forms which mimic fire geometry of the gap space*

List of reference symbol*: PÖ39] 1 Gap seal 2 First material 3 Outer snrfrce 4 inner surface

Claims (7)

5 Second material 6 see face 7 Gap wall A Sectional plane B Sectional plane mainframe m Exposure requirements Ready-made gor. dick® machine, sweetheart ^ siii'a ^ sl fbt ^ build your house for scaling your braided width, dumbbell material for your brain, ssmm3Si ^^ ms & as a composite material, wherein the composite material is as a swelling agent (5) as a material component, where it causes the moisture of the material to penetrate, and wherein the wall surface of the at least one slot of the structure is the writing material of the swelling material (5). inegvàÎÎôàÂïaSio, 2. The structure according to the invention is composed of at least two different gate valves, wherein at least one of the gp ^ ssftivb ¢ 2} defines the geometric shape of the structure and at least one prime molding component is a mesh. The doping material is formed as a swelling material (5). 3 »· te-L or claim 2: serite structures, mset of the swelling material is a millenary, layered, pomegranate or staple material arranged in the kotnpozii material. 4 * Structure according to claim 1: ,,, 2 :, or 3; they have different swelling behaviors and different agility. 5, 1-4; The device according to any one of claims 1 to 3, the medicament, the first material mixer (2) being temporarily formed as a partial shield (5), optionally in partial shade, The structure according to any one of claims 1 to 3, wherein the layered composite material is at least one of the layers with a carrier medium of: a. (5). % A. Structures according to any one of claims 1 to 7, characterized in that the layer material of the second material has an alternating layer position p). the farther side of the gap is growing, 9. The 14 *. Device according to any one of the claims, characterized in that the second material is {S} a friable material, mainly wood or heat-treated wood. 111. $ 1-. One of the at least one of the foregoing claims is a polymeric material based on the present invention. ti The 1-kk t æ æ æ æ æ æ æ æ æ æ æ æ anyagok anyagok anyagok anyagok anyagok anyagok anyagok anyagok anyagok anyagok anyagok anyagok anyagok anyagok anyagok anyagok anyagok anyagok anyagok anyagok anyagok anyagok anyagok anyagok anyagok anyagok anyagok anyagok anyagok anyagok anyagok anyagok anyagok anyagok anyagok anyagok anyagok anyagok anyagok anyagok anyagok anyagok anyagok anyagok anyagok anyagok anyagok anyagok anyagok anyagok anyagok anyagok anyagok anyagok anyagok anyagok 2,5 2,5 2,5 2,5 2,5 2,5 2,5 2,5 2,5 2,5 2,5 2,5 2,5 2,5 2,5. 12. A structure according to any one of the claims, characterized in that a sensor is installed to overcome the wear and tear of the structure. 13. M 1 -12. Device according to any one of claims 1 to 4, characterized in that a. structure is made of split mgaktsss lizard iron.