DK9400202U4

DK9400202U4 - Roots pump

Info

Publication number: DK9400202U4
Application number: DK9400202U
Authority: DK
Inventors: Holm Ejner Iversen; Bundgaard Bent Petersen
Original assignee: Agrometer A S
Priority date: 1994-05-02
Filing date: 1994-05-02
Publication date: 1994-10-28

Description

Den foreliggende opfindelse angår en Roots-pumpe, fortrinsvis til transport af væsker og omfattende et hus, der har en central husdel, et første og et andet sidedæksel og montageflanker for pumpens montering på et fundament, to indgribende stempler, der er placeret i huset, og som er i kontakt med slidplader i huset, hvorhos det første sidedæksel tillige afgrænser et gearhus, der understøtter den ene ende af pumpens aksler, og som har en udragende trækaksel for pumpens drift.The present invention relates to a Roots pump, preferably for transporting liquids and comprising a housing having a central housing portion, a first and a second side cover and mounting flanks for mounting the pump on a foundation, two engaging pistons located within the housing, and in contact with wear plates in the housing, the first side cover also defining a gear housing supporting one end of the pump shafts and having a protruding pull shaft for the pump operation.

Pumper af denne type anvendes oftest til at pumpe trægtflydende væsker samt væsker, der indeholder forskellige urenheder, som forårsager et slid på pumpens tænder samt på den indvendige side i pumpehuset. Pumpen anvendes for eksempel til slam fra rensningsanlæg og til olieindustri .Pumps of this type are most often used to pump inert liquids as well as liquids containing various impurities which cause wear on the pump teeth and on the inside of the pump housing. The pump is used, for example, for sewage sludge and for the oil industry.

Pumpen er som regel beregnet til at blive monteret på et fundament, hvor pumpehusets trækaksel skal liniestilles med trækakslen på en motor. Såfremt pumpen og/eller motoren afmonteres for udskiftning af stempler og/eller slidplader, kræves der en efterfølgende opretning af pumpen. Ved de kendte pumper er det således ikke usædvanligt, at der til udskiftning af slidplader og stempler medgår seks til otte timer. Det er således nødvendigt at afmontere pumpen fra rørstrengen for at kunne adskille pumpen og udtage stemplerne og slidpladerne og isætte nye stempler og slidplader.The pump is usually intended to be mounted on a foundation where the pump shaft of the pump housing must be aligned with the shaft of an engine. If the pump and / or motor is removed for replacement of pistons and / or wear plates, a subsequent alignment of the pump is required. Thus, with the known pumps, it is not uncommon for six to eight hours to replace wear plates and pistons. Thus, it is necessary to remove the pump from the pipe string in order to separate the pump and remove the pistons and wear plates and insert new pistons and wear plates.

Det er formålet med den foreliggende opfindelse at anvise en Roots-pumpe af den indledningsvis nævnte type, hvori ulemperne ved en langsom renovering er afhjulpet.It is the object of the present invention to provide a Roots pump of the type mentioned above, wherein the disadvantages of a slow renovation are remedied.

Dette opnås ifølge den foreliggende opfindelse med en Roots-pumpe af den indledningsvis nævnte type, som er særpræget ved, at det andet sidedæksel definerer et lejedæksel for understøtning af den anden ende af pumpens aksler, at montageflangerne er fastgjort til den centrale husdel, at pumpens udløb og indløb kun er forbundet med husets centrale del, at pumpens aksler har et tværsnit for rotationsmæssig med-bringning af stemplerne, som er frit aksialt forskydelige på akslerne, at i det mindste slidpladen ved gearhuset har en ydre kontur svarende til den indre kontur af husets centrale del, og at i det mindste denne slidplade er fastholdt i pumpen ved fastskruning til endedækslet.This is achieved according to the present invention with a Roots pump of the type mentioned initially, which is characterized in that the second side cover defines a bearing cover for supporting the other end of the pump shafts, that the mounting flanges are attached to the central housing part, outlet and inlet are connected only to the central part of the housing, that the pump shafts have a cross section for rotationally carrying the pistons which are freely axially displaceable on the shafts, that at least the wear plate at the gear housing has an outer contour corresponding to the inner contour of the the central part of the housing, and that at least this wear plate is retained in the pump by screwing to the end cover.

Med en sådan Roots-pumpe kan den centrale husdel samt sidedækslet, der er forbundet med gearhuset samt den dermed forbundne motor, forblive monteret på fundamentet fast forbundet med motoren og den rørstreng, hvori pumpen er monteret. Samtidig er pumpen indrettet til at klare store belastninger, da pumpens aksler er lejret i begge ender.With such a Roots pump, the central housing portion as well as the side cover associated with the gear housing as well as the associated motor can remain mounted on the foundation firmly connected to the motor and the pipe string in which the pump is mounted. At the same time, the pump is designed to handle large loads as the pump shafts are mounted on both ends.

Når slidplader og/eller stempler skal udskiftes, er det således alene tilstrækkeligt at afmontere det sidedæksel, som definerer lejedækslet. Herefter vil det være muligt at forskyde stemplerne aksi alt for eventuel udskiftning eller for at fjerne disse ved udskiftning af den slidplade, som er monteret ved gearhuset. Ved at fastskrue slidpladen fra endedækslet ved gearhuset kan denne slidplade forskydes gennem husets centrale del, da slidpladens ydre kontur svarer til den centrale dels indre kontur. Herefter kan slidpladen eventuelt vendes, hvis den er beregnet til dobbeltsidet slid, eller en ny slidplade kan monteres, hvorefter de gamle stempler eller nye stempler kan forskydes ind over akslerne. Slidpladen ved det afmonterede endedæksel udskiftes eller vendes ligeledes. Herefter kan sidedækslet, der definerer lejedækslet, igen monteres på husets centrale del. Roots-pumpen er herefter klar til brug uden behov for fornyet opretning af motor/trækaksel og/eller yderligere montagearbejde.Thus, when wear plates and / or pistons need to be replaced, it is sufficient to remove the side cover which defines the bearing cover. Thereafter, it will be possible to displace the pistons axially for any possible replacement or to remove them by replacing the wear plate mounted at the gear housing. By screwing the wear plate from the end cover at the gear housing, this wear plate can be displaced through the central part of the housing, since the outer contour of the wear plate corresponds to the inner contour of the central part. The wear plate may then be reversed if it is intended for double-sided wear or a new wear plate can be mounted, after which the old pistons or new pistons can be displaced over the shafts. The wear plate at the removed end cover is also replaced or reversed. Then the side cover, which defines the bearing cover, can be mounted again on the central part of the housing. The Roots pump is then ready for use without the need to re-align the motor / shaft and / or further assembly work.

Det har vist sig, at en renovering af pumpen ifølge opfindelse kan ske på ca. ¼ time. Der er således tale om en væsentlig besparelse i forhold til de kendte pumper.It has been found that a refurbishment of the pump according to the invention can take place in approx. ¼ hour. Thus, this is a significant saving compared to the known pumps.

Ved renovering af Roots-pumpen er det stemplerne, der hyppigt skal skiftes eller vendes. Således skal stemplerne skiftes ca. 10 gange for hver gang, der skal skiftes lejer i pumpen, og slidpladerne skal skiftes ca. hver 3. gang, der skiftes stempler. Det er således ganske væsentligt, at især stemplerne skiftes hurtigt og enkelt, og at dette skift kan ske på stedet uden brug for opretning, da udskiftning herved kan foretages uden avanceret hjælpeudstyr af en person uden særlig fagmæssig kunnen.When renovating the Roots pump, the pistons often need to be changed or turned over. Thus, the pistons must be changed approx. 10 times for each time that bearings need to be changed in the pump and the wear plates must be changed approx. every 3 times, pistons are changed. Thus, it is essential that the pistons in particular be replaced quickly and simply, and that this change can take place on the spot without the need for rectification, since replacement can be done without advanced auxiliary equipment by a person with no special skill.

En Roots-pumpe ifølge opfindelsen er ifølge en fordelagtig udførelsesform forsynet med en slidforing i husets centrale del. En sådan slidforing vil kunne udskiftes efter behov blot ved at løsne spændeor-ganer i huset og foretage en aksial forskydning af slidforingen i for- hold til den centrale del i forbindelse med udskiftning af slidplader. Det vil således være muligt at forlænge Roots-pumpens levetid, og det vil samtidig være muligt at renovere den centrale del af huset uden væsentlig forøgelse af den tid, der medgår ved renovering.According to an advantageous embodiment, a Roots pump according to the invention is provided with a wear liner in the central part of the housing. Such a wear liner can be replaced as needed simply by loosening the clamping means in the housing and making an axial displacement of the wear liner relative to the central part in connection with the replacement of wear plates. Thus, it will be possible to extend the service life of the Roots pump, and at the same time it will be possible to renovate the central part of the house without significantly increasing the time spent on renovation.

Opfindelsen vil herefter blive forklaret nærmere under henvisning til den medfølgende tegning, hvor fig. 1 viser et eksploderet billede af de væsentligste dele for en Roots-pumpe ifølge opfindelsen, fig. 2 et længdesnit gennem Roots-pumpen, og fig. 3 et partielt snit af Roots-pumpen. set fra den ene ende.The invention will now be explained in more detail with reference to the accompanying drawing, in which fig. 1 shows an exploded view of the essential parts of a Roots pump according to the invention; FIG. 2 is a longitudinal section through the Roots pump; and FIG. 3 is a partial section of the Roots pump. seen from one end.

Roots-pumpen vil blive beskrevet under samtidig henvisning til tegningens tre figurer.The Roots pump will be described with reference to the three figures of the drawing.

I fig. 1 ses en Roots-pumpe 1, der er beregnet til væsketransport. Pumpen l's hus omfatter en central husdel 2 samt to sidedæksler 3,4. Sidedækslet 3 er samtidigt et gearhus med en udragende trækaksel 4, som er forbundet med en gearmotor 5. Gearmotoren 5 er monteret på et fundament 6. Inde i pumpen er der monteret to indgribende stempler 7. Stemplerne 7 er på hver side i indgreb med slidplader 8,9, der er fastskruet til hvert sit endedæksel 3 henholdsvis 4. Stemplerne 7 er tillige i indgreb med en slidforing 10, der er beregnet til anbringelse inde i den centrale husdel 2. Endedækslet 4, der tjener som lejedæksel for aksler 11, er fastskruet til husets centrale del ved hjælp af et antal skruer 12, der er anbragt langs lejedækslet 4's omkredskant. Roots-pumpen 1 er monteret på fundamentet 6 via montageflanger 13, der kun er fastgjort til den centrale husdel 2. Pumpen er forsynet med et indløb og et udløb 14,15, der kun er fastgjort til husets centrale del 2. Det bemærkes, at gennemstrømningsretningen gennem pumpen kan vælges valgfrit afhængigt af omdrejningsretningen for gearmotoren 5.In FIG. 1 is a Roots pump 1 intended for fluid transport. The housing of the pump 1 comprises a central housing part 2 as well as two side covers 3,4. The side cover 3 is at the same time a gear housing with a protruding shaft 4, which is connected to a gear motor 5. The gear motor 5 is mounted on a foundation 6. Two engaging pistons 7 are mounted inside the pump. The pistons 7 engage on each side with wear plates. 8,9, which are screwed to each end cap 3 and 4 respectively. The pistons 7 are also engaged with a wear liner 10 intended for placement within the central housing part 2. The end cap 4, which serves as a bearing cap for shafts 11, is screwed to the central portion of the housing by means of a plurality of screws 12 disposed along the circumferential edge of the bearing cover 4. The root pump 1 is mounted on the foundation 6 via mounting flanges 13, which are attached only to the central housing part 2. The pump is provided with an inlet and an outlet 14,15, which is only attached to the central part of the housing 2. It is noted that the flow direction through the pump can be optionally selected depending on the direction of rotation of the gear motor 5.

Slidpladerne 8,9 er monteret på sidedækslerne ved hjælp af skruer 16. I det mindste slidpladen 8, der er monteret ved gearhuset 3, har en ydre kontur svarende til den indre kontur af husets centrale del 2. Herved kan slidpladen forskydes gennem huset, efter endedækslet 4 er afmonteret, og efter stemplerne 7 er trukket af akslerne 11. Akslerne 11 er spline-aksler, hvorpå stemplerne 7 er anbragt frit aks i alt forskydeligt. Slidpladen 8 og stemplerne 7 kan således udskiftes, uden det er nødvendigt at demontere husets centrale del 2 fra fundamentet eller fra den rørstreng, hvortil flanger 14,15 for indløb og udløb er monteret.The wear plates 8,9 are mounted on the side covers by means of screws 16. At least the wear plate 8, which is mounted at the gear housing 3, has an outer contour corresponding to the inner contour of the central part of the housing 2. This allows the wear plate to be displaced through the housing, after the end cover 4 is removed and after the pistons 7 are pulled by the shafts 11. The shafts 11 are spline shafts, on which the pistons 7 are disposed freely in all slidable positions. Thus, the wear plate 8 and the pistons 7 can be replaced without the need to remove the central part 2 of the housing from the foundation or from the pipe string to which flanges 14,15 for inlet and outlet are mounted.

Idet husets centrale del 2 er forsynet med en slidforing 10, er det muligt at opnå længere drifttid mellem de totale renoveringer, samtidig med at det kun er slidforingen og ikke hele huset, der skal skiftes. Slidforingen udskiftes meget enkelt ved, at løsne fire styk spæn-dejern 24 i huset og foretage en aksial forskydning af slidforingen 10 i forhold til husets centrale del 2.As the central part 2 of the housing is provided with a wear liner 10, it is possible to achieve longer operating time between the total renovations, while only the wear liner and not the whole housing need to be changed. The wear liner is replaced very simply by loosening four pieces of tensioner 24 in the housing and making an axial displacement of the wear liner 10 relative to the central part 2 of the housing.

Drifttiden mellem renoveringer er gjort så lang som mulig, idet stemplerne ved hver stempel top er forsynet med en skrabekant 17. Hvert af stemplerne er i det mindste delvis fremstillet af et kunststofmateriale, og eventuel slidende elementer i den væske, som skal pumpes, vil derfor kunne forårsage et stort slid på stemplerne, hvis ikke disse var forsynet med en skrabekant 17. Eventuelle urenheder, som befinder sig inde i pumpehuset, vil således blive medbragt af skrabekanterne istedet for at slide stempel toppene eller den indre kontur i husets centrale del 2.The operating time between renovations is made as long as possible, with the pistons at each piston top being provided with a scratching edge 17. Each of the pistons is at least partially made of a plastic material and any abrasive elements in the liquid to be pumped will therefore could cause excessive wear on the pistons if they were not provided with a scraper edge 17. Any impurities located inside the pump housing will thus be carried by the scraping edges instead of sliding the piston peaks or the inner contour of the central part of the housing.

Husets indløb og udløb er forsynet med flanger 14,15 ifølge DIN-norm til direkte montering i en rørstreng. Herved bliver Roots-pumpen lettere at montere.The inlet and outlet of the housing are provided with flanges 14,15 according to DIN standard for direct mounting in a pipe string. This makes the Roots pump easier to install.

I lejedækslet 4 er der dannet en boring 18, som står i forbindelse med forsiden af tætningerne. Boringen 18 er altid afproppet ud til det fri, og ved normal drift, det vil sige under 5 Bar, er der ikke forbindelse med sugesiden og forsiden af tætningerne, og det vil være muligt uden gener for levetid at vende omdrejningsretningen og dermed pumperetningen.In the bearing cover 4, a bore 18 is formed which communicates with the front of the seals. The bore 18 is always plugged out into the open, and in normal operation, that is, below 5 Bar, there is no connection with the suction side and the front of the seals, and it will be possible without reversing the life direction and thus the pump direction.

Såfremt pumpen skal benyttes ved et tryk, der er over 5 Bar, kan der opstå levetidsproblemer med tætningerne og dermed lejerne. I denne situation vendes slidpladerne 8 og 9, så huller 21 vender mod sugesiden. Ved at benytte huller 21 som borebøsning kan man på stedet gennembryde den tynde væg 20 mellem boringen 18 og husets indre. Dermed skabes kortslutning mellem sugesiden og forsiden af tætningerne 19. Det betyder, at tætningerne nu kun skal modstå sugetrykket. Det betyder samtidig, at man ikke kan vende pumperetningen. Denne gennembrydning foretages meget enkelt på stedet, hvor pumpen monteres. Det gennemgående hul 21 i slidpladen 8 er i det mindste anbragt ved pumpens sugeside. Boringen 18 er lavet i både tryk- og sugeside, og aflastningsboringen 21 kan derfor frit foretages afhængigt af pumpens rotationsretning.If the pump is to be used at a pressure exceeding 5 Bar, there may be lifetime problems with the seals and thus the bearings. In this situation, the wear plates 8 and 9 are turned so that holes 21 face the suction side. By using holes 21 as a drilling socket, the thin wall 20 can be pierced on the spot between the bore 18 and the interior of the housing. This creates a short circuit between the suction side and the front of the seals 19. This means that the seals now only have to withstand the suction pressure. This also means that the pump direction cannot be reversed. This breakthrough is made very easily at the site where the pump is mounted. The through hole 21 in the wear plate 8 is at least disposed at the suction side of the pump. The bore 18 is made in both the pressure and suction side, and the relief bore 21 can therefore be freely made depending on the direction of rotation of the pump.

Ved at forbinde pumpens sugeside med boringen 18 opnås en trykaflastning i tætningerne 19, således at eventuel utæthed i pumpen undgås. Herved kan pumpens drifttid mellem renoveringer forøges.By connecting the suction side of the pump with the bore 18, a pressure relief is obtained in the seals 19, so that any leakage in the pump is avoided. This allows the pump operating time between renovations to be increased.

Som det især fremgår af fig. 2, er pumpen 1 af en type, hvor akslerne 11 er lejret såvel i lejerne 23 i lejedækslet som i lejer 22 ved gearhuset 3. Herved kan pumpen arbejde med større belastninger end det er muligt med pumper, som blot er understøttet i lejer ved akslens ene ende.As can be seen in particular from FIG. 2, the pump 1 is of a type in which the shafts 11 are mounted both in the bearings 23 in the bearing cover and in bearings 22 at the gear housing 3. This allows the pump to work with greater loads than is possible with pumps supported only in bearings by the shaft. one end.

Claims

A Roots pump, preferably for transporting liquids and comprising a housing having a central housing portion, a first and a second side cover and mounting flanks for mounting the pump on a foundation, two engaging pistons located in the housing which are in contact with wear plates in the housing, the first side cover also defining a gear housing which supports one end of the pump shafts and having a protruding shaft for the pump operation, characterized in that the second side cover defines a bearing cover for supporting the other end of the pump shafts, that the mounting flanges are attached to the central housing part, that the outlet and inlet of the pump are connected only to the central part of the housing, that the pump shafts have a cross section for rotationally carrying the pistons which are freely axially displaceable on the shafts, that in the the smallest wear plate at the gear housing has an outer contour corresponding to the inner contour of the central part of the housing, and that at least this wear plate is firmly held dt in the pump by screwing to the end cover.

Roots pump according to claim 1, characterized in that a wear liner is mounted inside the central part of the housing.

Roots pump according to claim 1 or 2, characterized in that the inlet and outlet of the housing are integral with flanges molded in the central part with flanges according to DIN standard for direct mounting in a pipe string.

Roots pump according to any one of the preceding claims, characterized in that the shafts of the pump are spline shafts on which the pistons are mounted.