US3126338A

US3126338A - Hermetically sealable mounting means

Info

Publication number: US3126338A
Authority: US
Priority date: 1959-11-30
Publication date: 1964-03-24
Anticipated expiration: 1981-03-24
Also published as: FR1273346A; NL108445C; DE1094193B; NL256419A; CH383884A; GB948789A

Description

United States Patent 3,126,338 IETICALLY SEALABLE MOUNTING MEANS FUR A CENTRIFUGAL DRUM Peter Steinacker, Oelde, Westphalia, Germany, assignor to Westfalia Separator A.G., Oelde, Westphalia, Germany,

a German corporation Filed Nov. 29, 1960, Ser. No. 72,404 (Ilairns priority, application Germany Nov. 30, 1959 7 Claims. (Cl. 233-23) The present invention relates to a hermetically sealable mounting means for a centrifugal drum, and more particularly to such mounting means which are oscillatingly displaceable together with the drum out of the normal position thereof.

Hermetically sealed centrifugal drums, such as conventional separator drums, usually have stationary inlet and outlet lines sealed with respect to the rotating drum. Such constructions are generally used for the separation of liquid mixtures, especially where the material to be centrifugally treated must not be exposed to contact with the atmosphere. Additionally, drum separators of the foregoing type are useful for the centrifuging of solids from liquids advantageously, since the smooth passage into the drum of the material to be treated takes place without the breaking up of solids suspended in the incoming liquid. For example, it may be desirable to clarify a liquid with respect to suspended solids yet recover the solids portion of the material being treated substantially in its identical form and without the same having been broken up by the centrifugal action. For the most part, however, since the clarifying capacity of a centrifugal drum depends to a great degree upon the size of solids particles, a higher clarifying capacity of the drum separator is achieved when the breaking up of the solids particles is avoided. An efiicient clarification or separation of solids particles from liquids as well as any separation of a lighter from a heavier fraction of material, albeit a mixture of a lighter liquid fraction and heavier liquid fraction, a lighter liquid fraction and heavier solid fraction, may accordingly take place. It is known to employ solid packings or liquid seals for the sealing of the stationary inlet and outlet lines with respect to the rotating centrifugal drum parts, in order to achieve the passage into the drum of material to be treated and the passage from the drum of separated fractions without leakage. However, the radial oscillations of the centrifugal drum out of the normal position thereof act unfavorably on such packings or seals. Radial oscillations of the drum shaft out of the normal axial position thereof often disadvantageously occur during centrifugal operations. Consequently, liquid packings or seals between the stationary inlet and outlet lines and the corresponding drum parts either permit the leakage of liquid or the entry of air, while solid packings or seals are subject to high wear and tear so as eventually to permit such leakage, entry of air, or remixing of the separated components.

Attempts have been made to decrease the rate of wear and tear on solid packings and seals by constructing the same, for example, as sealing sleeves such that the point of connection will form an abutting edge developed as a thin sealing lip. In such constructions either the sleeve will be stationary and the stationary lip will slidingly abut a rotating conduit of the centrifuge, or else the sealing sleeve and lip will rotate with the centrifuge and will slidingly abut a stationary conduit for the centrifugal drum. By employing a thin sealing lip as the only abutting connecting surface, the wear is decreased since an edge is employed having minimal sliding contact area. By employing such sealing sleeves having a thin sealing lip in the form of rubber, flexibleplastic or other material, the elasticity of the connection is increased.

Constructions have also been proposed whereby the with this arrangement.

3,126,338 Patented Mar. 24, 1964 ice stationary inlet and outlet lines which flow-connect with sealing sleeves of the foregoing type are formed of flexible or elastic material or include a flexible or elastic portion therealong so that such stationary lines will yield in consequence of varying lateral pressure caused by the radial oscillations of the drum out of the normal path. Therefore the pressure which would otherwise be exerted fully against the sealing sleeves by the drum parts is taken up to some extent by the elastic or flexible inlet and outlet line construction. With respect to slight radial oscillations out of the normal path of rotation wherein only a slight deflection or movement of the elastically or flexibly arranged inlet and outlet lines is required, the pressure transmitted by the sealing sleeve connected therewith is correspondingly slight so that thedesired function is achieved On the other hand, however, greater oscillations of the centrifugal drum out of its normal path, i.e., wherein a greater amplitude of radial movement is encountered, would require a correspondingly greater deflection or movement such that the forces to be transmitted by the sealing sleeves would be correspondingly greater. Accordingly, considerable wear and tear will occur with respect to the sealing sleeves since such greater forces are not readily transmitted to the flexibly connected stationary inlet and outlet lines.

Particularly large amplitude oscillations of the drum out of its normal axial path will occur where solids separated from a carrier liquid are ejected from the drum at specific time intervals. This is normally carried out using a drum separator, for example, having peripheral discharge openings therein which are closed during the separating operation and then opened for discharging the collected solids. The sudden opening of the discharge openings to effect the emptying of the solids from the drum and the irregular emergence of the solids through the discharge openings result in imbalances. These cause strong and violent shaking of the rotating drum and consequently lead to radial oscillations of the drum out of its normal rotational path and strong wear and tear on the seals. Moreover, with respect to marine centrifugal drum arrangements, because of the rocking and rolling of the ship, relative movements of considerable extent occur between the rotating and stationary parts of the centrifugal drum arrangement leading to similar problems of wear and tear. This is particularly true at the outermost positions of the drum axis with respect to the normal axis of rotation, i.e., at the point where the ocsillating direction reverses from one side to the other.

For the aforementioned reasons, it has not been possible in the past to use effectively self-discharging or automatically discharging sludge separators and marine separators of the heremeticaly sealed type.

It is an object of the present invention to overcome the foregoing drawbacks and to provide a hermetically sealable radially displaceable mounting means for a centrifugal drum whereby the mounting means may be displaced together with the drum out of the normal position so that no undue pressure will be exerted on the packing or seal between the stationary and rotating parts of the drum arrangement.

Other and further objectives will become apparent from a study of the within specification and accompanying drawing, in which FIGURE 1 is a schematic side elevational view partly in section of a centrifugal drum arrangement in accordance with the invention, and

found that a hermetically scalable mounting arrangement may be provided for a centrifugal drum having inlet means and outlet means for the material treated within the drum, which comprises mounting means for rotatably receiving the drum, said mounting means being positioned for oscillatory displacement together with the drum out of the normal rotational path of the drum. The mounting means includes chamber means for outwardly enclosing the drum inlet and outlet means for the material treated in the drum in hermetically sealed, rotatable condition, the chamber means being adapted for flow connecting the inlet and outlet means with an inlet source and outlet recovery means, respectively, for the material treated within the drum.

The mounting means is normally rotationally stationary and the arrangement is provided with means for rotating the drum within the mounting means with the inlet and outlet means of the drum in hermetically sealed condition. In this manner the mounting means may be limitedly radially displaced as a unit together with the drum out of the normal position.

Preferably the mounting means includes bearing means for rotatably receiving the drive shaft of the centrifugal drum and a casing enclosing the bearing means having a removable hood or cover portion for permitting access to the interior of the casing.

The chamber means includes at least one inlet-sourceconnectable inlet chamber flow connected with the drum inlet means and at least one outlet-recovery-means-connectable outlet chamber flow connected with the drum outlet means. The portions of each said chamber connected with the drum inlet and outlet means are preferably defined as resilient annular surfaces or edges adapted to slidably contacting the corresponding portions of the drum inlet and outlet means in rotational sealing abutment therewith.

In accordance with the preferred embodiment of the invention, the drum inlet means is flow connected to an inlet source for the material treated within the drum through the inlet chamber, and the drum outlet means is flow connected to an outlet recovery means for said material through the outlet chamber, by flexible conduit means, respectively.

In accordance with one embodiment of the invention wherein the centrifugal drum is equipped with peripheral discharge openings therein for the removal of solids material separately from a liquid carrier therefor, for example a conventional sludge discharge drum separator having automatic means for opening and closing the discharge openings, the cover means is additionally provided with peripheral discharge conduit means for conducting away material peripherally discharged from the drum through the peripheral discharge openings or ports.

Thus, a hermetically sealed centrifugal drum arrangement is provided in accordance with the present invention wherein a centrifugal drum having drum inlet and outlet means for material treated therewithin is provided with mounting means for rotatably receiving the drum, said mounting means being positioned for displacement together with the drum out of the normal rotational path of the drum. The mounting means specifically include support means or bearing means for rotatably receiving the drum and cover means or casing for enclosing the drum and support means. Advantageously, the support means and cover means are both mounted for radial oscillatory displacement together with the drum out of the normal position thereof, such that the chamber means forming a part of the cover means which outwardly encloses the drum inlet and outlet means in hermetically sealed condition will also be displaced in like manner. As a result, no wear and tear will take place between the rotating inlet and outlet parts of the drum and the chamber means operatively connected thereto, since all of these parts will be simultaneously radially displaced as the drum is subjected to radial displacement. Due to the provision for flexible connections between the inlet source and outlet recovery means, on the one hand, and

the chamber means on the other, any radial displacement will be taken up and not transmitted to the stationary inlet source and outlet recovery means, respectively.

In accordance with the invention, therefore, a centrifugal drum is provided in which even very great amplitudes of oscillation and corresponding radial displacement of the centrifugal drum may be accommodated without unfavorably influencing the packing or seal between the ro tating and stationary parts of the drum arrangement for feeding and withdrawing flowable materials treated within the drum. In this manner, the major cause for accelerated wear and tear of the packings or seals between the rotating and stationary parts of the drum arrangement is avoided and only the normal wear and tear of such parts will occur independently of the movements of the centrifugal drum out of its normal rotational path.

Referring to FIGURE 1 of the drawing, a centrifugal drum 9 is arranged within a frame 1 such that its shaft 3 is operatively connected to the drive wheel 2 of any conventional drive means (not shown). The drum 9 is positioned within a cover 7 which generally encloses the drum. The shaft 3 is mounted for rotation within the lower portion of cover or casing 7 by means of upper radial bearing 4, lower radial bearing 5 as well as end bearing 6, so that shaft 3 may be rotated by means of drive wheel 2 operatively connected with gear 2' of shaft 3. The lower portion of cover or casing 7 is positioned on resilient mounting surface 1" which may be formed of rubber or other suitable shock-absorbing material positioned on frame 1 while the intermediate portion of cover 7 adjacent to the upper portion of shaft 3 is connected to frame 1 by means of a plurality of circumferential resiliently mounted neck bearings 8 which serve to dampen the simultaneous radial oscillations of cover 7 and drum 1. It will be appreciated in this manner that as drum 9 is subjected to radial displacement with respect to its normal axis of rotation, the cover 7 within which shaft 3 is mounted will also be radially displaced in the same manner. Generally, a pendulum movement or oscillation of the drum 9, shaft 3 and cover 7 will take place about the mid-point of surface 1" as pivot point which will be dampened by neck bearings 8.

Attached to the upper portion of stationary cover 7 is a removable hood 10 also stationarily positioned with respect to the rotating drum. The upper portion of hood 10 is constructed as a chamber means 10 for enclosing the inlet and outlet means of the drum in hermetically sealed condition.

The upper portion of drum 9 is provided with a neck portion 17 including three concentric flow pipes. The outermost flow pipe of neck portion 17 terminates within lower outlet chamber 16', the intermediate flow pipe terminates within upper outlet chamber 15, while the innermost flow pipe terminates within inlet chamber 17 An annular outlet flow conduit 16" passes from the drum interior between the outermost and intermediate flow pipes and communicates in hermetically sealed condition with lower outlet chamber 16' and, in turn, with outlet recovery pipe 16 having interposed therealong a flexible pipe portion 20 capable of accommodating axial movement of pipe 16. Flow conduit 16 serves to remove a heavier liquid fraction from the drum separately from a lighter liquid fraction and solids content of the material being treated in the drum.

In the same way, an annular outlet flow conduit 15" passes from the drum interior between the intermediate and innermost flow pipes and communicates in hermetically sealed condition with upper outlet chamber 15' and, in turn, with outlet recovery pipe 15 having interposed therealong a flexible pipe portion 19 for the same purpose as flexible pipe portion 20. Flow conduit 15" serves to remove from the drum a lighter liquid fraction separately from the heavier liquid fraction removed through flow conduit 16".

The innermost flow pipe extends through the lower outlet chamber 16 and the uppermost outlet chamber and terminates within inlet chamber 1'7 so as to communicate in hermetically sealed condition flexible inlet conduit 18, inlet pipe 14 and inlet chamber 17' with the interior of the drum by means of the flow conduit 17 the innermost flow pipe of neck portion 17. Flexible inlet conduit 18 serves the same purpose for the inlet arrangement as flexible portions 19 and serve for the outlet arrangements. The material to be treated in the drum, therefore, may comprise a sludge material including a mixture of a lighter and a heavier liquid fraction as well as solids material suspended in the liquid.

An annular resilient seal 13, such as a rubber seal, is interposed between the lower adjacent portion or lower outlet chamber 16 and the outermost concentric pipe of neck portion 17 so as to form a connection between the adjacent rotating portion of drum 9 and the stationary portion of chamber means 10 thereat. In like manner, a seal 12 is *mterposed between the lower adjacent portion of upper outlet chamber 15 and the intermediate concentric pipe of neck portion 17 so as to form a connection between the adjacent rotating portion of drum 9 and the stationary portion of chamber means 10" therea-t. A similar seal 11 is interposed between inlet chamber 17' and the innermost concentric pipe of neck portion 17 so as to form a connection between the adjacent rotating portion of drum 9 and the stationary portion of chamber means 10 thereat. In this connection, the chamber means 10' includes the housing portion of hood 1% which encloses chambers 16, 15' and 17' which form the connection between the stationary parts of the hermetically scalable chamber means and the rotating parts of the drum therewithin.

Centrifugal drum 9 is provided in this embodiment as a sludge discharge separating drum having a plurality of spaced apart openings or ports 9" defined along its periphery at a level intermediate the upper and lower ends of the drum. At the level of ports 9 an annular opening 23' with interposed ribs is provided along the periphery of cover 7. Frame 1 in turn includes a trough chamber 23 outwardly of and peripherally enclosing the portion of cover 7 provided with opening 23. A suitable discharge conduit 23" flow communicates trough chamber 23 with collecting means (not shown) for recovering the sludge fraction separated within the drum. in order topermit radial movement ct" hood 10 in relation to frame 1, resilient rings or strips 24 interconnect the upper and lower edges of the peripheral portion of cover 7 containing opening 23 with the adjacent edges of trough chamber 26.

For control of the opening and closing of sludge discharge ports 9 of drum 9, any conventional means may be provided, such as a slidable piston having an annular ring portion axially movable from a position closing to a position opening ports 9 and vice versa. Such constructions are well known, and commonly use a control liquid, such as water, which in this case continuously passes through flexible conduit 22 (which serves the same purpose as flexible portions 18, 19 and 21)), pipe 21 and nozzle 21' into a lower annular recess 9 in drum 9. Due to the centrifugal motion of drum 9, the liquid received within recess 9" will pass into the drum via control inlet 9". Such liquid serves to displace the piston within the drum to close the ports 9'. After interruption of the liquid feed, the ports 9 are opened under the pressure of the bowl-fillings (as is known). It will be appreciated in this respect that when the control liquid is allowed to pass through nozzle 21, the same will enter drum 9 and displace the slidable piston to axially move the annular ring portion from a position normally opening to a position closing the ports 9. Upon termination of the flow of the control liquid through nozzle 21, the control liquid within the drum will flow out through suitable exit ports so that the piston return to the 6 a position normally opening ports 9". Any control liquid which may be lost in the vicinity of recess 9" will be prevented by shield 21" from permeating the lower drum parts, including shafit 3, bearings 4, etc., and such control liquid will leave by means of exit ports 7 and 1'.

It will be appreciated that with respect to stationary frame 1, cover 7 including hood 1t} and chamber means 10 will execute pendulum movements or radial displacements from the normal axis of rotation together with drum 9, shaft 3 and neck portion 17 Without any load being placed on the resilient seals 11, 12 and 13 other than the normal load present by dint of the sliding contact between the moving parts, i.e., the concentric flow pipes of neck portion 17, and the stationary parts, i.e., chambers 16, 15' and 17, connected to the pipes of neck portion 17 by means of said resilient seals 11, 12 and 13. Any pendulum movements or radial displacement will be radially taken up by the flexible portions 18, 1-9 and 2G, neck bearings 8, as well as the surface 1" which serves as a base pivot point for the entire mounting on frame 1.

Thus, a construction is provided in accordance with the invention wherein the drum 9 and inlet and outlet means, including neck portion 17, on the one hand, and the chamber means for flow connecting said inlet and outlet means with the drum exterior in hermetically sealed condition, on the other hand, are unable to execute any relative movements with respect to one another other than the rotational movement of the drum parts.

In FIGURE 2 a similar embodiment of the hermetically sealed chamber means in accordance with the invention is shown in enlarged detail. Drum is provided with conventional outlet flow conduits 150" and outlet flow conduits 150" for the specifically heavier liquid fraction and lighter liquid fraction, respectively, passing out from the drum interior. Flow conduits 16%" are spaced about the periphery of the drum Wall and communicate with lower outlet chamber 160', while flow conduits 150" pass from the drum interior to upper outlet chamber 150'. An axial inlet flow conduit 17h" flow communicates inlet chamber 17% with the interior of the drum for feeding the materials to be treated into the drum, The lower connection between outlet chamber 160' and the neck portion 176, which includes outlet flow conduits 160 and 15% as well as inlet flow conduit 170", is provided by annular resilient seal 130. In the same manner, annular resilient seals are provided as the upper connection of chamber 160' and as the lower connection of chamber 150, respectively. Annular resilient seals 110 are provided as the upper connection of chamber 15th and as the lower connection of chamber 170', respectively. Chamber 160 flow communicates with outlet recovery pipe 160 having interposed therealong a flexible pipe portion 200 capable of accommodating axial movement of pipe 160. In the same Way, chamber 159' flow communicates with outlet recovery pipe 150 having interposed therealong a flexible pipe portion 190 capable of accommodating axial movement of pipe 150. Flexible inlet conduit 18h interposed in the inlet conduit flow communicates inlet pipe and inlet chamber 170' with the interior of the drum via flow conduit 17%". The function and arrangement of the foregoing parts are similar to those of the corresponding parts in FIGURE 1.

The chamber means 160, which includes in hermetically sealed condition the inlet and outlet conduits for drum 90, is positioned upon hood 100 which is releasably connected to cover 70 by spring loaded latches 70'. It will be seen that chamber 160 is defined by annular element ltitla and annular element 160a situated in pressing engagement upon the upper portion of hood 100. Chamber 1513 is defined by annular element a and annular element 170a situated in pressing engagement upon the upper portion of annular element a. Chamber is defined by annular element 140a situated in pressing engagement upon annular element 150a. The particular annular elements making up the chamber means 100' are maintained in stacked relationship in pressing engagement one upon the next by means of lever 30 and coacting spindle 31 pressing against cover 33 of annular element 140a. Lever 30 and spindle 31 are positioned on bracket 32 secured to hood 100 by bolt 34.

The chamber means 100, therefore, will efficiently maintain the inlet and outlet flow conduits of the drum in hermetically sealed condition so that the material to be treated in the drum may be passed therethrough via flexible portion 180 and the liquid material already treated in the drum may be passed therefrom via

flexible portions

190 and 200. In the same manner as carried out in accordance with the construction of FIGURE 1, the chamber means 100', hood 100 and cover 70 will be radially displaced together with drum 90 and neck portion 170 out of the normal path of rotation. It will be appreciated that any leakage which may occur in the normal centrifugal operations at the seals 110, 120 and 130, as is known, will be carried off by means of conventional run-

off grooves

101, 102, 103, 104 and 105.

What is claimed is:

1. Hermetically sealable centrifugal drum arrangement which comprises a centrifugal drum having at the top end portion thereof drum inlet means and outlet means for the material treated within the drum, mounting means rotatably receiving and completely enclosing the drum, stationary base means, said mounting means being pivotally positioned on said base means for displacement together with the drum out of the normal rotational path of the drum and including chamber means outwardly resiliently enclosing in hermetically sealed rotatable condition the drum inlet and outlet means for the material treated in the drum, inlet source flexible conduit means and outlet recovery flexible conduit means, said chamber means flow communicating said inlet and outlet means with said inlet source and outlet recovery means, respectively, for the material treated within the drum, and said chamber means being displaceable together with the drum inlet and outlet means out of said normal path.

2. Drum arrangement according to claim 1 wherein said mounting means are rotationally stationary yet mounted on said base means for limited oscillatory displacement together with the drum out of normal position.

3. Drum arrangement according to claim 2 wherein said chamber means includes at least one inlet chamber flow connecting said inlet source means with the drum inlet means and at least one outlet chamber flow connecting said outlet recovery means with the drum outlet means.

4. Drum arrangement according to claim 3 wherein the corresponding portions of said chambers connected with the drum inlet and outlet means are defined as resilient annular surfaces adapted to slidably contact the corresponding portions of said drum inlet and outlet means in rotational sealing abutment therewith.

5. Drum arrangement according to claim 4 wherein said drum is provided with a drive shaft, said mounting means include bearing means for rotatably receiving the drive shaft of the centrifugal drum and a casing enclosing said bearing means and the drum, said casing having a emovable hood portion for permitting access to the interior of the casing, said chamber means being positioned on said hood portion, and said bearing means, casing, hood portion and chamber means being mounted resiliently on said base means for limited oscillatory displacement together with the drum out of normal position.

6. Drum arrangement according to claim 5 wherein said drum is provided with peripheral drum discharge ports and said casing is additionally provided with hermetically sealed peripheral discharge conduit means, for conducting away material peripherally discharged from the drum through said peripheral drum discharge ports.

7. In a centrifugal drum arrangement, including a centrifugal drum mounted for rotation and having inlet and outlet means rotatable therewith and stationary inlet source means and outlet recovery means, respectively, for the material treated in the drum, the improvement which comprises mounting means rotatably receiving and completely enclosing the drum, stationary base means, said mounting means being positioned resiliently pivotally on said base means for oscillatory displacement together with the centrifugal drum, and said mounting means including chamber means outwardly resiliently enclosing the drum inlet and outlet means in hermetically sealed rotatable condition, and flexible conduit means, said chamber means hermetically sealably flow communicating said inlet and outlet means by said flexible conduit means with said inlet source and outlet recovery means, respectively, for the material treated in the drum, said chamber means being displaceable together with the drum inlet and outlet means out of the normal rotational path of the drum.

References Cited in the file of this patent UNITED STATES PATENTS 2,043,350 Forsberg June 9, 1936 2,358,779 Tholl Sept. 26, 1944 2,461,674 Aronson Feb. 15, 1949 2,575,689 Smith Nov. 20, 1951 2,916,201 Hemfort et al. Dec. 8, 1959 3,026,701 Houser Mar. 27, 1962 3,040,899 Kron June 26, 1962 3,061,181 Gooch Oct. 30, 1962 FOREIGN PATENTS 630,307 Germany May 25, 1936

Claims

1. HERMETICALLY SEALABLE CENTRIFUGAL DRUM ARRANGEMENT WHICH COMPRISES A CENTRIFUGAL DRUM HAVING AT THE TOP END PORTION THEREOF DRUM INLET MEANS AND OUTLET MEANS FOR THEMATERIAL TREATED WITHIN THE DRUM, MOUNTING MEANS ROTATABLY RECEIVING AND COMPLETELY ENCLOSING THE DRUM, STATIONARY BASE MEANS, SAID MOUNTING MEANS BEING PIVOTALLY POSITIONED ON SAID BASE MEANS FOR DISPLACEMENT TOGETHER WITH THE DRUM OUT OF THE NORMAL ROTATIONAL PATH OF THE DRUM AND INCLUDING CHAMBER MEANS OUTWARDLY RESILIENTLY ENCLOSING IN HERMETICALLY SEALED ROTATABLE CONDITION THE DRUM INLET AND OUTLET MEANS FOR THE MATERIAL TREATED IN THE DRUM, INLET SOURCE FLEXIBLE CONDUIT MEANS AND OUTLET RECOVERY FLEXIBLE CONDUIT MEANS, SAID CHAMBER MEANS FLOW COMMUNICATING SAID INLET AND OUTLET MEANS WITH SAID INLET SOURCE AND OUTLET RECOVERY MEANS, RESPECTIVELY, FOR THE MATERIAL TREATED WITHIN THE DRUM, AND SAID CHAMBER MEANS BEING DISPLACEABLE TOGETHER WITH THE DRUM INLET AND OUTLET MEANS OUT OF SAID NORMAL PATH.