TRANSVERSE DISC OF A CENTRIFUGE SCREW, AND SOLID-BOWL SCREW CENTRIFUGE

Abstract

The invention relates to a transverse disc (60) of a centrifuge screw (30) for stabilising a screw hub structure. According to the invention, at least one opening (70) is formed at least in some sections on at least 75% of all the imaginary circle lines (71) of the transverse disc (60) between the centre point (M) and the transverse disc circumference (72).

Claims

1. A transverse disc (60) of a centrifuge screw (30) for stabilizing a screw hub structure (56), characterized in that at least one opening (70) is formed, at least in some sections, on at least 75% of all the imaginary circle lines (71) of the transverse disc (60) between the center point (M) and the transverse disc circumference (72).

2. The transverse disc (60) according to claim 1, characterized in that at least one opening (70) is formed at least in some sections on all of the imaginary circle lines (71) of the transverse disc (60)

3. The transverse disc (60) according to claim 1, characterized in that the openings (70, 73, 75, 78, 80) have different geometries and/or opening sizes and/or arrangement patterns.

4. The transverse disc (60) according to claim 1, characterized in that several openings (74) are formed in a cam-shape or an oval-shape or elliptically and are in particular arranged in pairs.

5. The transverse disc (60) according to claim 1, characterized in that, based on the transverse disc circumference (72), several openings (78) are formed as recesses, in particular as U-shaped recesses arranged in particular in pairs.

6. The transverse disc (60) according to claim 1, characterized in that several openings (73) are circularly formed and in particular arranged in pairs.

7. The transverse disc (60) according to claim 1, characterized by an opening (80) formed in the center point (M) of the transverse disc (60) having a circular shape (81) with additional further circle segment-like recesses (82), in particular three circle segment-like recesses (82).

8. The transverse disc (60) according to claim 1, characterized by substantially semicircular recesses (90) formed at the transverse disc circumference (72) and arranged to be evenly distributed.

9. A solid bowl screw centrifuge (10) having a centrifuge screw (30) comprising a screw hub (32) preferably created of longitudinal bars (58) at least in some sections, characterized in that at least one transverse disc (60) according to claim 1 is arranged within the screw hub (32).

10. The solid bowl screw centrifuge (10) according to claim 9, characterized in that, independent of the pond depth (52) formed within the drum (16) of the solid bowl screw centrifuge (10), the transverse disc (60) forms an axial passage for a centrate produced within the solid bowl screw centrifuge (10).

Description

[0058] Shown are in:

[0059] FIG. 1 a longitudinal cut of a solid bowl screw centrifuge according to the invention having at least one transverse disc according to the invention; and

[0060] FIG. 2 a representation of a transverse disc according to the invention.

[0061] In the following, the same reference numerals will be used for identical parts or parts of identical action.

[0062] In FIG. 1, a solid bowl screw centrifuge 10 is represented, which extends substantially along a horizontal longitudinal axis 12. The solid bowl screw centrifuge 10 has an outer housing 14, in which a drum 16 is mounted to be rotational about the longitudinal axis 12. By rotating the drum 16 at high rotational speed, a centrifugal force can be produced within it, by means of which a product to be clarified can be separated into a heavy phase and a light phase. For this purpose, the drum 16 is supported at a first drum bearing 18 and a second drum bearing 20. The represented solid bowl screw centrifuge 10 is a 2-phase solid bowl screw centrifuge. The transverse disc according to the invention, however, can also be realized in a 3-phase solid bowl screw centrifuge.

[0063] At the drum 16, an inlet 22 for the product to be clarified and an outlet 24 for the heavy phase and an outlet 26 for the light phase are formed. For rotating the drum 16, a drive 28 is provided. The outlet 26 acts as an overflow for the light phase located radially inside the drum 16, so that the light phase exits there autonomously, if a predetermined level, the so-called pond depth 52, is reached within the drum 16.

[0064] So that the heavy phase located radially outside within the drum can be discharged from the drum 16, a centrifuge screw 30 is provided within the drum 16. The centrifuge screw 30 is rotated relative to the drum 16 by means of the drive 28. Thereby, the material of the heavy phase is discharged to radially inside and thus to the outlet 24 along a cone formed at the drum 16.

[0065] For this purpose, the centrifuge screw 30 is configured having a screw hub 32 extending longitudinally to the longitudinal axis 12, which screw hub is surrounded radially outside by a screw spiral coil 34. The screw hub 32 consequently serves the purpose of supporting the screw spiral coil 34 in the radial direction, of transmitting a torque from the drive 28 to the screw spiral coil 34, and of receiving in particular tensile forces and thrust forces in this case. The screw hub 32 is configured by a grid structure 56 in the cylindrical longitudinal section 36.

[0066] The grid structure 56 is configured by means of twelve longitudinal bars 58, which are evenly distributed at uniform distances across the circumference of the screw hub 32 in the longitudinal direction thereof, thus in parallel to the longitudinal axis 12.

[0067] The preferred number of longitudinal bars 58 is between 8 and 16, in particular between 10 and 14. Radially outside, the longitudinal bars 58 each create a contact surface for the screw spiral coil 34 and are supported radially inside on transverse discs 60. The longitudinal bars 58 extend in this case beyond the transverse discs 60, which are oriented transversely to the longitudinal axis 12 and thus create an inner support for the longitudinal bars 58.

[0068] Between two and six oblique struts 64 extend in each case between two transverse discs 60.

[0069] Within the conical longitudinal section 38, a screw hub 32 having a shell surface 44 is formed. The shell surface 44 is substantially closed and in particular configured by means of a sheet metal or a tube surface. The centrifuge screw 30 is mounted to be rotatable by means of a first screw bearing 40 and a second screw bearing 42.

[0070] The inlet region 48 is in particular defined by the inlet tube 46. The inlet tube 46 serves for supplying the product to be clarified centrally within the inlet region 48 into the interior of the screw hub 32. Due to the screw hub 32 created of longitudinal bars 58, the solid bowl screw centrifuge 10 has a large pond depth 52.

[0071] In FIG. 2, a transverse disc 60 according to the invention is represented in an enlarged manner.

[0072] It can be recognized that a plurality of openings 70 is formed within the transverse disc 60. These openings 70 have different geometries, cross-sections and arrangement patterns. The openings are arranged in such a manner, are formed with respect to the geometry in such a manner, and have such opening sizes that on at least 75% of all of the imaginary circle lines 71 of the transverse disc 60 from the center point M to the transverse disc circumference 72 at least one opening 70 or a section of an opening 70 is formed at least in some sections.

[0073] In other words, the transverse disc 60 enables an axial passage of the centrate due to the openings 70 formed at each pond depth 52 prevailing within the solid bowl screw centrifuge 10. At the same time, the stability of the transverse disc 60 and thus of the screw hub 32 or the centrifuge screw 30 is not negatively affected.

[0074] First, an opening 70/80 formed in the center point M of the transverse disc 60 can be recognized. This opening 80 has a circular form 81 with additionally further circle segment-like recesses 82. In the present case, three circle segment-like recesses 82 are formed. The circle segment-like recesses are evenly distributed over the circumference of the circular form 81. In other words, the circle segment-like recesses 82 each are arranged at an angle of 120° relative to one another.

[0075] Starting from the center point M in the radial direction, furthermore openings 70 are arranged, which are formed as circular openings 73. As compared to all of the other openings 70 of the transverse disc 60, these openings 73 have the smallest opening size.

[0076] It can be recognized that these circular openings 73 each are arranged in pairs. Two circular openings 73 create a group of openings 83 in each case. Six circular openings 73, and thus three groups of openings 83 are formed.

[0077] The groups of openings 83 in turn are evenly arranged in the circular arc direction on the transverse disc 60. In other words, the groups of openings 83 are in turn arranged at an angle of 120° relative to one another. It can be recognized that the groups of openings 83 are arranged in relation to the center point opening 80 such that a group of openings 83 is in each case arranged between two circle segment-like recesses 82. In other words, the groups of openings 83 are in turn arranged at an angle of 120° relative to one another. It can be recognized that in some sections the openings 73 as well as the circle segment-like recesses 82 of the opening 80 are formed at the exemplary circle line 71′.

[0078] Additionally, three circular openings 73′ are formed. The openings 73′ have a smaller diameter than the circular openings 73. The three circular openings 73′ each are formed to lie radially inside a recess 90. Moreover, the circular openings 73′ are formed in a radial extension to the central distance of the circular openings 73 of the groups of openings 83.

[0079] The transverse disc furthermore has openings 70 formed in a cam-shape. These cam-shaped openings 74 in turn are arranged in pairs.

[0080] It can be recognized that six cam-shaped openings 74 are formed, wherein three groups of openings 84 are formed in total with respect to the cam-shaped openings 74. As cam-shaped openings 74, such an opening is to be understood, which has the shape of a cam of a camshaft in a top view of the opening 74. It can be recognized that the shape of the openings 74 corresponds to the shape of a steep cam. In order to be able to create such a cam-shaped opening 74, the openings have two circle segments, namely the first circle segment 75 and the second circle segment 76. The second circle segment 76 is in this case larger and has a larger radius than the first circle segment 75.

[0081] The two circle segments 75 and 76 are connected to one another by means of a straight connecting line 77, so that the cam-shape of the openings 74 is created. It can be recognized that all of the cam-shaped openings 74 are arranged such that the smaller circle segments or the smaller arc segments 75 each point in the direction of the transverse disc circumference 72, and the second circle segments or the larger arc segments 76 point to the inside in the direction of the center point M.

[0082] The groups of openings 84 are arranged in such a manner that a group of openings 84 and a group of openings 83 are in each case arranged alternatingly in the circumferential direction U. It can be recognized by means of the exemplary circle line 71″ that both the circular openings 73 and the cam-shaped openings 74 are partially formed on this circle line 71″.

[0083] The transverse disc moreover has openings 70 formed as U-shaped recesses 78. Six of such U-shaped recesses 78 are formed in total on the transverse disc 60.

[0084] Two of these recesses 78 are each arranged in pairs and create a group of openings 88. In total, three groups of openings 88 are thus formed, which in turn are arranged to be evenly distributed over the transverse disc 60. The groups of openings 88 each are arranged at 120° relative to one another.

[0085] It can be recognized by means of the exemplary circle lines 71′″ and 71* that at these circle lines 71′″ and 71* both the cam-shaped openings 74 and the U-shaped openings 78 are formed at least in some sections.

[0086] The transverse disc 60 furthermore has recesses 90 at the transverse disc circumference 72. These recesses are substantially formed to be semicircular. The recesses 90 serve in particular for receiving and fixing longitudinal bars 58 of a screw hub 32.

[0087] In the present case, twelve of such recesses 90 are formed. Accordingly, it is possible for a screw hub 32 to be created of twelve longitudinal bars 58. It is not necessary, however, to receive a longitudinal bar in all of the recesses 90. In other words, when less than twelve longitudinal bars are present, each second recess 90 may be left free, for example.

[0088] The transverse disc 60 is created of alternatingly arranged circle sectors 94 and 95.

[0089] A first circle sector 94 comprises a circle segment-like recess 82 and a group of openings 84 formed of cam-shaped openings 74. A second circle sector 95 comprises a group of openings 83 formed of circular openings 73, and a group of openings 88 formed of U-shaped recesses 78. Furthermore, a circular opening 73′ is respectively formed in the second circle sector 95.

[0090] The circle sectors 94 and 95 are alternatingly arranged to one another in the circumferential direction U. In total, three first circle sectors 94 and three second circle sectors 95 are formed.

[0091] Due to the differently formed openings, 70 or 73, 74, 78 and 80, an axial passage for centrate produced within the solid bowl screw centrifuge 10 is enabled to be formed independent of the pond depth 52 formed within the drum 16 of the solid bowl screw centrifuge 10.

LIST OF REFERENCE NUMERALS

[0092] 10 solid bowl screw centrifuge

[0093] 12 longitudinal axis

[0094] 14 outer housing

[0095] 16 drum

[0096] 18 first drum bearing

[0097] 20 second drum bearing

[0098] 22 inlet for the product to be clarified

[0099] 24 outlet for the heavy phase

[0100] 26 outlet for the light phase

[0101] 28 drive

[0102] 30 centrifuge screw

[0103] 32 screw hub

[0104] 34 screw spiral coil

[0105] 36 cylindrical longitudinal section

[0106] 38 conical section

[0107] 40 first screw bearing

[0108] 42 second screw bearing

[0109] 44 closed shell surface

[0110] 46 inlet tube

[0111] 48 inlet region

[0112] 52 pond depth

[0113] 56 grid structure

[0114] 58 longitudinal bar

[0115] 60 transverse disc

[0116] 64 oblique strut

[0117] 70 opening

[0118] 71, 71′, 71″, 72′″, 71* circle line

[0119] 72 transverse disc circumference

[0120] 73, 73′ circular opening

[0121] 74 cam-shaped opening

[0122] 75 first circle segment

[0123] 76 second circle segment

[0124] 77 straight connecting line

[0125] 78 U-shaped recess

[0126] 80 opening of center point

[0127] 81 circular form

[0128] 82 circle segment-like recess

[0129] 83 group of openings

[0130] 84 group of openings

[0131] 88 group of openings

[0132] 90 recess

[0133] 94 first circle sector

[0134] 95 second circle sector

[0135] M center point

[0136] U circumferential direction