NO793367L - AXIAL POWER RESTRICTION DEVICE, SPECIFICALLY FOR SUSPENSION BODIES. - Google Patents
AXIAL POWER RESTRICTION DEVICE, SPECIFICALLY FOR SUSPENSION BODIES.Info
- Publication number
- NO793367L NO793367L NO793367A NO793367A NO793367L NO 793367 L NO793367 L NO 793367L NO 793367 A NO793367 A NO 793367A NO 793367 A NO793367 A NO 793367A NO 793367 L NO793367 L NO 793367L
- Authority
- NO
- Norway
- Prior art keywords
- spindle
- spindle nut
- nut
- stated
- axial
- Prior art date
Links
- 239000000725 suspension Substances 0.000 title 1
- 238000006073 displacement reaction Methods 0.000 claims description 3
- 230000001105 regulatory effect Effects 0.000 claims description 3
- 238000002955 isolation Methods 0.000 description 3
- 230000036316 preload Effects 0.000 description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- 230000000903 blocking effect Effects 0.000 description 1
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- 239000010802 sludge Substances 0.000 description 1
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
- F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
- F16K31/00—Actuating devices; Operating means; Releasing devices
- F16K31/02—Actuating devices; Operating means; Releasing devices electric; magnetic
- F16K31/04—Actuating devices; Operating means; Releasing devices electric; magnetic using a motor
- F16K31/047—Actuating devices; Operating means; Releasing devices electric; magnetic using a motor characterised by mechanical means between the motor and the valve, e.g. lost motion means reducing backlash, clutches, brakes or return means
- F16K31/048—Actuating devices; Operating means; Releasing devices electric; magnetic using a motor characterised by mechanical means between the motor and the valve, e.g. lost motion means reducing backlash, clutches, brakes or return means with torque limiters
-
- 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
- F16H—GEARING
- F16H35/00—Gearings or mechanisms with other special functional features
- F16H35/10—Arrangements or devices for absorbing overload or preventing damage by overload
Description
Innretning for aksialkraftbegrensning, særlig for avstengningsorganer. Device for axial force limitation, especially for shut-off devices.
Foreliggende oppfinnelse vedrorer en innretning for aksialkraftbegrensning, særlig for avstengningsorganer, som angitt i hovedkravets innledning. The present invention relates to a device for axial force limitation, particularly for shut-off devices, as stated in the introduction of the main claim.
Ved de vanlige avstengningsarmaturer blir grensestillingene av de bevegelige deler, dvs. generelt spindelendestillingene, over-våket og styrt av avstandsbrytere. Dersom denne styring svikter eller blir forbikoblet, skjer utkobling av drivmotoren med momentbrytere. Som folge av tregheten i systemet drivmotor-drev, vil det moment som faktisk utoves mot de belastede armaturdeler dog være storre enn det moment som er innstilt på momentbryteren. Det faktisk opptredende moment kan bli så stort at det skader de berorte armaturdeler eller f.eks. skyver kileskyvere så langt inn i setet at de.ikke lenger kan åpnes. With the usual shut-off fittings, the limit positions of the moving parts, i.e. generally the spindle end positions, are monitored and controlled by distance switches. If this control fails or is bypassed, the drive motor is switched off with torque switches. As a result of the inertia of the drive motor-drive system, the torque that is actually applied to the loaded fitting parts will however be greater than the torque that is set on the torque switch. The actually occurring torque can be so great that it damages the fitting parts in contact or e.g. pushes wedge pushers so far into the seat that they can no longer be opened.
Det samme kan også sis om svikt av momentbryteren. Driften blir da som regel forst koblet ut ved egen termobeskytteIse. The same can also be said about failure of the torque switch. The operation is then usually switched off first by its own thermal protection ice.
På grunn av de usikre friksjonsforhold i driften og mellom spindelmutteren og spindelen er dreiemomentet et upålitelig mål på den aksiale spindelkraft. Due to the uncertain friction conditions in operation and between the spindle nut and the spindle, the torque is an unreliable measure of the axial spindle force.
Slurekoblinger benyttes ikke ved armaturer på grunn av manglen-de pålitelighet. Sludge couplings are not used for fittings due to the lack of reliability.
En dimensjonering av armaturen for det maksimalt mulige drivmo-ment ville medfore svære dimensjoner og store omkostninger. I tillegg til de ovennevnte usikkerhetsmomenter kommer påkjenninger ved ekspansjonsdifferanser som folge av temperaturforand-iringer mellom spindelen og armaturhuset, når spindelen sitter fast i endest.illingene. Det kan da opptre aksiale forkilinger med fare for at spindelen boyer seg eller brister, at kileskyvere setter hhv. skjærer seg fast osv. Dimensioning the fixture for the maximum possible drive torque would entail large dimensions and large costs. In addition to the above uncertainties, there are stresses due to expansion differences as a result of temperature changes between the spindle and the armature housing, when the spindle is stuck in the end bearings. Axial wedging can then occur, with the risk that the spindle bends or breaks, that the wedge pushers set or gets stuck etc.
Ved rorbrudd etter ventiler, f.eks. omstyrings- eller isolasjonsventiler, kan aksialkraften som ved lukning oppstår som folge av trykkdifferansen gjennom ventilskiven, bli så stor, avhengig av det preliminære trykk og bruddtverrsnittet etter armaturen, at spindelen utsettes for en utillatelig påkjenning eller at drivmomentet ikke lenger strekker til. for å bevege spindelen. In case of rudder breakage after valves, e.g. diverting or isolation valves, the axial force that occurs during closing as a result of the pressure difference through the valve disc can become so great, depending on the preliminary pressure and the fracture cross-section after the valve, that the spindle is exposed to an inadmissible stress or that the drive torque is no longer sufficient. to move the spindle.
Mangelfull lukking kan f.eks. ved omkoblingsarmaturer etter rorbrudd i forvarmeren fore til at turbinen settes i fare, idet vannet kunne stromme over bruddstedet til forvarmerens damprom og deretter fra tappeledningen til turbinen. Slike problemer kan også oppstå i ferskdamp- eller fodevanns-trykkledninger i kjernekraftverk, idet rorbrudd må forutsettes å kunne'forekomme. Armaturene må da kunne lukke pålitelig for at det ikke skal av-gis radioaktivitet til omgivelsene. Inadequate closure can e.g. in the case of switching fittings after a rudder break in the preheater causes the turbine to be put at risk, as the water could flow over the break point into the preheater's steam room and then from the tap line to the turbine. Such problems can also occur in fresh steam or feed water pressure lines in nuclear power plants, since rudder breakage must be assumed to be able to occur. The fittings must then be able to close reliably so that no radioactivity is emitted into the surroundings.
Ved bruk av drivhoder med avfjæret spindelmutter, slik det er vanlig i dag, vil mutteren boyes elastisk ned ("durchfedern") ved overskridelse av fjærforspenningen, slik at armaturen luk-kes selv uten drivmotor og spindelens aksialkraft begrenses. Ved storre nominelle bredder og slag er dette armaturhode dog meget langt. Derfor benyttes for slike formål ofte armaturer som betjenes med et eget medium. I trykkfri tilstand eller ved lavt trykk må disse armaturer dog betjenes manuelt eller med en ekstra drivmotor. When using drive heads with a sprung spindle nut, as is common today, the nut will bend elastically down ("durchfedern") when the spring preload is exceeded, so that the armature closes even without a drive motor and the spindle's axial force is limited. However, with larger nominal widths and strokes, this fitting head is very long. Therefore, fittings that are operated with a separate medium are often used for such purposes. However, in a depressurized state or at low pressure, these fittings must be operated manually or with an additional drive motor.
Ovenstående ulember unngås ved hjelp av oppfinnelsen, som er angitt i hovedkravets karakteriserende del. The above disadvantages are avoided by means of the invention, which is stated in the characterizing part of the main claim.
Oppfinnelsens gjenstand skal i det fSigende beskrives nærmere under henvisning av et utforelseseksempel som er vist i tegnin-gen, hvor The object of the invention shall be described in more detail below with reference to an embodiment shown in the drawing, where
fig. 1 er en skisse av en innretning ifolge oppfinnelsen brukt I på eh stor avstengningsarmatur, j. fig. 1 is a sketch of a device according to the invention used I on a large shut-off fitting, j.
fig. 2 viser innretningen ifolge fig. 1 i snitt. fig. 2 shows the device according to fig. 1 on average.
I fig. 1 er innretningen for aksialkraftbegrensning betegnet med 1. Den er anbrakt på en avstengningsarmatur, av hvilken ba-re ovre parti er vist og er festet til dennes flens 2,3. Ovre del av innretningen er drivenheten 4, som omfatter motor og drev for drift av spindelmutteren. Nedre del av innretningen In fig. 1, the device for limiting axial force is denoted by 1. It is placed on a shut-off fitting, of which the bare upper part is shown and is attached to its flange 2,3. The upper part of the device is the drive unit 4, which includes the motor and drive for operating the spindle nut. Lower part of the facility
er spindelmutterlagringen 5, som vil bli nærmere omtalt nedenfor i forbindelse med fig. 2. Gjengespindelen 6 strekker seg inn i drivenheten 4, hvor den •kan skrues inn i spindelmutteren som vist i fig. 2. I ovre ende av drivenheten 4 er det anordnet et ratt 7 for manuell betjening av spindelen 6. is the spindle nut bearing 5, which will be discussed in more detail below in connection with fig. 2. The threaded spindle 6 extends into the drive unit 4, where it •can be screwed into the spindle nut as shown in fig. 2. At the upper end of the drive unit 4, a steering wheel 7 is arranged for manual operation of the spindle 6.
Spindelmutteren er vist oppbrutt. I sin ovre ende har den en reguleringsfjær 9, som kan gli i et spor 10 for et drivhjul 11, som sitter på spindelmutteren med trang klaring. Drivhjulet 11, som drives av en ikke vist elektrisk motor, som er anordnet i drivenheten 4, og f.eks. et heller ikke vist tannhjuls- eller snekkegir, er fiksert i aksial retning. The spindle nut is apparently broken. At its upper end, it has a regulating spring 9, which can slide in a groove 10 for a drive wheel 11, which sits on the spindle nut with narrow clearance. The drive wheel 11, which is driven by an electric motor not shown, which is arranged in the drive unit 4, and e.g. a gear or worm gear, also not shown, is fixed in the axial direction.
Spindelmutterlagringen 5 omfatter et hus 12, som er lukket mot drivenheten 4 hhv. avstengningsarmaturen 2 med en ovre og en nedre flens 13 hhv. 14. Gjennom boringer 15 og 16 i flensene 13 hhv. 14 forloper spindelmutteren 8 oppover og inn i driven-, The spindle nut bearing 5 comprises a housing 12, which is closed against the drive unit 4 or the shut-off fitting 2 with an upper and a lower flange 13 respectively. 14. Through holes 15 and 16 in the flanges 13, respectively. 14, the spindle nut 8 extends upwards and into the driven,
heten 4 og over drivhjulet 11 samt ned i avstengningsarmaturen heat 4 and over the drive wheel 11 as well as down into the shut-off fitting
2. I sin ytterflate har spindelmutteren et omkretsspor 17 med 2. In its outer surface, the spindle nut has a circumferential groove 17 with
. likebent trapes-tverrsnitt. Dette omkretsspor opptar et antall kuler 18, som virker som tverrkulelagring for spindelmutteren når denne er fastholdt i lengderetning. Som ytre lopeflater for kulene 18 virker hulkileflater 19 og 20 for to lagerringer 21 hhv. 22, hvilkes sirkelsylindriske ytterflater sitter lengdefor-skyvbart i huset 12. Innbyrdes forskyvning av disse lagerringer . isosceles trapezoid cross-section. This circumferential groove accommodates a number of balls 18, which act as transverse ball bearings for the spindle nut when it is held longitudinally. As outer running surfaces for the balls 18, hollow wedge surfaces 19 and 20 act for two bearing rings 21 respectively. 22, whose circular-cylindrical outer surfaces sit longitudinally displaceable in the housing 12. Mutual displacement of these bearing rings
er begrenset avvet innad fremspringende anslag 23. i huset 12. I den normale stilling av spindelmutteren 8, dvs. fiksert stilling i lengderetningen, ligger lagerringene 21 og 22 under forspenningspåvirkning fra to tallerkenfjærsoyler 24 og 25, som er fastspent mellom de tilsvarende lagerringer 21,22 og flenser 13,14, i anlegg mot anslagets 23 skuldre. is limited inward projecting abutment 23 in the housing 12. In the normal position of the spindle nut 8, i.e. fixed position in the longitudinal direction, the bearing rings 21 and 22 are under the influence of preload from two plate spring columns 24 and 25, which are clamped between the corresponding bearing rings 21, 22 and flanges 13,14, in contact with the shoulders of the stop 23.
Ved tilsvarende valg av fjærkarakteristikken og forspenningen a] r fjærsoylene 24 og 25 oppnås at spindelmutteren, inntil en bestemt, fritt valgbar spindelkraft forblir fiksert i aksial retning av lageret som dannes av kulene 18, det ringformede spor 17 på spindelmutterens omkrets og de to hulkileflater 19 og 20 By corresponding selection of the spring characteristic and the preload a] r the spring coils 24 and 25, it is achieved that the spindle nut, until a specific, freely selectable spindle force, remains fixed in the axial direction by the bearing formed by the balls 18, the annular groove 17 on the circumference of the spindle nut and the two hollow wedge surfaces 19 and 20
i lagerringene 21 og 22. Når spindelmutteren dreies, vil gjengespindelen som er blokkert mot dreining bevege seg i aksial retning, opp eller ned, avhengig av mutterens dreieretning. Ved in the bearing rings 21 and 22. When the spindle nut is turned, the threaded spindle which is blocked against rotation will move in the axial direction, up or down, depending on the direction of rotation of the nut. By
overskridelse av spindelkraften som er avhengig av den innstil-te f jærf or spenning, frigis spindelmutteren og dermed spindelen i aksial retning, idet kulene 18 som folge av det ringformede exceeding the spindle force, which is dependent on the set spring tension, the spindle nut and thus the spindle is released in the axial direction, the balls 18 as a result of the annular
spors 17 skråflater presses ut av dette og presses inn i den ki-leformede spalte som dannes av de to hulkileflater 19,20 for lagerringene 21,22, og derved forskyver lagerringene mot mot-standen fra de to fjærsoylene 24,25. Spindelmutteren er da ikke the inclined surfaces of the track 17 are pressed out of this and pressed into the wedge-shaped gap formed by the two hollow wedge surfaces 19,20 for the bearing rings 21,22, thereby displacing the bearing rings against the resistance from the two spring coils 24,25. The spindle nut is not
bare fri i dreieretning, men også i aksial.retning. Den påvir-kes bare av friksjonskrefter. only free in the direction of rotation, but also in the axial direction. It is only affected by frictional forces.
Dersom overskridelsen av aksialkraften skyldes en aksial blokke-ring av spindelen, vil spindelmutteren etter utpressing av kulene 18 bevege seg i aksial retning. Denne bevegelse kan utnyttes for betjening av en grensebryter for utkopling av drivmotoren. Dersom denne bryter svikter, vil spindelmutteren forskyves så langt i aksial retning at den fores ut av drivtannhjulets 11 spor 10 med sin reguleringsfjær 9 eller at spindelen 6 er gått ut av gjengeinngrep. If the excess of the axial force is due to an axial blocking of the spindle, the spindle nut will move in the axial direction after the balls 18 have been pressed out. This movement can be used to operate a limit switch for disconnecting the drive motor. If this switch fails, the spindle nut will be displaced so far in the axial direction that it is pushed out of the drive gear 11's groove 10 with its regulating spring 9 or that the spindle 6 has gone out of thread engagement.
Dersom spindelen overbelastes av en aksialkraft som f.eks. opptrer som folge av trykkdifferanse på tvers av en ventiltallerken ved et rorbrudd etter en armatur, vil denne kraft påvirke spindelen og spindelmutteren i retning av lukking av ventiltallerkenen og spindel og mutter trekkes ut av spindelmutterlagringen inntil ventiltallerkenen sitter på sitt sete. Dette er uavhengig av om drivmotoren er i gang eller ikke. Denne aksialbevegelse av spindelmutteren kan igjen ut.lose en grensebryter eller en bryter for varsling av en skade i overvåkningsrommet eller for innkop-ling av drivmotoren, dersom denne var ute av drift, for tilbake-foring av spindelmutteren til den aksialt fikserte inngrepsstil-ling i spindelmutter-lagringen. If the spindle is overloaded by an axial force such as occurs as a result of a pressure difference across a valve plate in the event of a rudder break after an armature, this force will affect the stem and the stem nut in the direction of closing the valve plate and the stem and nut are pulled out of the stem nut bearing until the valve plate sits on its seat. This is independent of whether the drive motor is running or not. This axial movement of the spindle nut can again trigger a limit switch or a switch for notifying a damage in the monitoring room or for switching on the drive motor, if this was out of order, for returning the spindle nut to the axially fixed engagement position in the spindle nut bearing.
I tilfelle det opptrer et utillatelig hoyt trykk nedenfor ven-_ | tiltallerkenen ved lukket ventiltallerken, virker innretningen som sikkerhetsventil, idet ventiltallerkenen loftes fra sitt sete ved overskridelse av forspenningskraften.som er bestemt av fjærsoylene 24 og 25. In the event that an unacceptably high pressure occurs below ven-_ | the plate when the valve plate is closed, the device acts as a safety valve, as the valve plate is lifted from its seat when the biasing force, which is determined by the spring coils 24 and 25, is exceeded.
Påkjenninger, som skyldes ekspansjonsdifferanser som folge av temperaturforskjeller mellom spindelen og armaturhuset når spindelen sitter fast i endestillingene, begrenses kontrollert av de fjærbelastede lagerringer 21 og 22. Stresses, which are due to expansion differences as a result of temperature differences between the spindle and the armature housing when the spindle is stuck in the end positions, are controlled and limited by the spring-loaded bearing rings 21 and 22.
Denne innretning for aksialkraftbegrensning kan benyttes v.ed alle avstengningsarmaturer, f.eks. ved omkoblingsarmaturer, isolasjonsarmaturer m.v. Den tilfredsstiller kravet til kontrol-lerbar, begrensning av aksialkraften på spindelen, selv om strek-nings- og momentbryterne svikter eller forbikobles. Ved omkob-lings- eller isolasjonsventiler sikres således ved et rorbrudd etter armaturen ikke bare at spindelen beskyttes mot for hoy aksialkraft, men også at armaturen lukker. This device for limiting axial force can be used with all shut-off fittings, e.g. in the case of switching fittings, isolation fittings etc. It satisfies the requirement for controllable limitation of the axial force on the spindle, even if the tension and torque switches fail or are bypassed. In the case of switch-over or isolation valves, in the event of a rudder break after the armature, it is thus ensured not only that the spindle is protected against excessive axial force, but also that the armature closes.
Innretningen er også egnet for andre verktoy og arbeidsmaskiner, hvor begrensning av krefter som virker i lengderetning er nod-vendig for at skader skal hindres. The device is also suitable for other tools and work machines, where limiting forces acting in the longitudinal direction is necessary to prevent damage.
Claims (5)
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CH1092078 | 1978-10-23 |
Publications (1)
Publication Number | Publication Date |
---|---|
NO793367L true NO793367L (en) | 1980-04-24 |
Family
ID=4368212
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
NO793367A NO793367L (en) | 1978-10-23 | 1979-10-18 | AXIAL POWER RESTRICTION DEVICE, SPECIFICALLY FOR SUSPENSION BODIES. |
Country Status (8)
Country | Link |
---|---|
EP (1) | EP0010113A1 (en) |
JP (1) | JPS5557784A (en) |
AU (1) | AU5193579A (en) |
DK (1) | DK440679A (en) |
ES (1) | ES485261A1 (en) |
NO (1) | NO793367L (en) |
PL (1) | PL219107A1 (en) |
PT (1) | PT70351A (en) |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE3314781A1 (en) * | 1983-04-23 | 1984-10-25 | Deutsche Babcock Werke AG, 4200 Oberhausen | FITTING |
IT1258551B (en) * | 1992-06-08 | 1996-02-27 | Dante Cavalli | AXIAL STRESS LIMITER SAFETY DEVICE |
DE19535051C1 (en) * | 1995-09-21 | 1996-11-28 | Honeywell Ag | Spindle nut or threaded spindle arrangement |
DE10034482A1 (en) * | 2000-07-15 | 2002-01-24 | Ksb Ag | guard |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB793333A (en) * | 1956-03-12 | 1958-04-16 | Dodge Mfg Corp | Power transmission units with overload release means |
FR1397632A (en) * | 1964-05-19 | 1965-04-30 | Elmeg | Torque limiter for worm drive |
CH576672A5 (en) * | 1974-04-03 | 1976-06-15 | Sulzer Ag |
-
1978
- 1978-11-21 EP EP78200312A patent/EP0010113A1/en not_active Withdrawn
-
1979
- 1979-10-18 NO NO793367A patent/NO793367L/en unknown
- 1979-10-18 DK DK440679A patent/DK440679A/en unknown
- 1979-10-18 AU AU51935/79A patent/AU5193579A/en not_active Abandoned
- 1979-10-22 PT PT70351A patent/PT70351A/en unknown
- 1979-10-22 PL PL21910779A patent/PL219107A1/xx unknown
- 1979-10-22 ES ES485261A patent/ES485261A1/en not_active Expired
- 1979-10-23 JP JP13603179A patent/JPS5557784A/en active Pending
Also Published As
Publication number | Publication date |
---|---|
PT70351A (en) | 1979-11-01 |
ES485261A1 (en) | 1980-04-16 |
DK440679A (en) | 1980-04-24 |
AU5193579A (en) | 1980-05-01 |
PL219107A1 (en) | 1980-06-02 |
EP0010113A1 (en) | 1980-04-30 |
JPS5557784A (en) | 1980-04-28 |
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