EP0805890A1 - Trieuse sous pression de suspensions de fibres et crible pour ces trieuses sous pression - Google Patents

Trieuse sous pression de suspensions de fibres et crible pour ces trieuses sous pression

Info

Publication number
EP0805890A1
EP0805890A1 EP95907639A EP95907639A EP0805890A1 EP 0805890 A1 EP0805890 A1 EP 0805890A1 EP 95907639 A EP95907639 A EP 95907639A EP 95907639 A EP95907639 A EP 95907639A EP 0805890 A1 EP0805890 A1 EP 0805890A1
Authority
EP
European Patent Office
Prior art keywords
sieve
approximately
axis
groove
screen
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP95907639A
Other languages
German (de)
English (en)
Other versions
EP0805890B1 (fr
Inventor
Jochen Gustav Pfeffer
Erich Czerwoniak
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Voith Finckh Fiber Systems GmbH and Co KG
Original Assignee
Hermann Finckh Maschinenfabrik GmbH and Co
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Hermann Finckh Maschinenfabrik GmbH and Co filed Critical Hermann Finckh Maschinenfabrik GmbH and Co
Priority to AT95907639T priority Critical patent/ATE181120T1/de
Priority to EP98122514A priority patent/EP0905309B1/fr
Priority claimed from EP98122514A external-priority patent/EP0905309B1/fr
Publication of EP0805890A1 publication Critical patent/EP0805890A1/fr
Application granted granted Critical
Publication of EP0805890B1 publication Critical patent/EP0805890B1/fr
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Classifications

    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21D—TREATMENT OF THE MATERIALS BEFORE PASSING TO THE PAPER-MAKING MACHINE
    • D21D5/00—Purification of the pulp suspension by mechanical means; Apparatus therefor
    • D21D5/02—Straining or screening the pulp
    • D21D5/023—Stationary screen-drums
    • D21D5/026—Stationary screen-drums with rotating cleaning foils
    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21D—TREATMENT OF THE MATERIALS BEFORE PASSING TO THE PAPER-MAKING MACHINE
    • D21D5/00—Purification of the pulp suspension by mechanical means; Apparatus therefor
    • D21D5/02—Straining or screening the pulp
    • D21D5/16—Cylinders and plates for screens
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00—Metal working
    • Y10T29/49—Method of mechanical manufacture
    • Y10T29/496—Multiperforated metal article making
    • Y10T29/49604—Filter

Definitions

  • Pressure sorter for sorting fiber suspensions and sieve for such a pressure sorter
  • the invention relates to a pressure sorter for fiber suspensions, in particular for the preparation of fiber suspensions obtained from waste paper, with a housing in which a stationary sieve, which is rotationally symmetrical to a sieve axis, is arranged, which in the housing has an inlet space encompassed by the sieve from outside the Siebs lying Gutstoff ⁇ space separates, with feed space and Gutstoff syndromem communicate with each other via passage channels located in the sieve wall, as well as with a rotor which can be driven by a motor around the sieve axis, an inlet communicating with a first axial end of the inlet space for the treatment to be treated Fiber suspension, a good material outlet communicating with the accepted material space and a reject material outlet communicating with a second axial end of the inlet space, the rotor being treated with several, in the circumferential direction of the rotor, to produce positive and negative pressure surges in the fiber suspension to be treated
  • the following profile elements arranged in the inlet space each have a first flank lying in front in the
  • the invention relates to a pressure sorter of this type, as disclosed and claimed in WO 94/00634 by Hermann Finckh Maschinenfabrik GmbH & Co.
  • the invention relates to a sieve for sorting fiber suspensions, which is rotationally symmetrical to a sieve axis and has an upstream side for the fiber suspension to be sorted and an outflow side opposite this, for pressure sorters with a rotor which can be driven in rotation about the sieve axis and which is the On the inflow side of the sieve adjacent circumferential profile elements for generating positive and negative pressure surges in the fiber suspension to be sorted, the sieve on its inflow side having successive grooves running approximately parallel to the sieve axis, each of which - in the circumferential direction of the profile elements - in the circumferential direction of the sieve seen - is delimited by a front and a rear groove side wall and has a groove base, into which at least one sieve passage opens, and wherein the front groove side wall is more inclined with
  • the invention relates to such a screen, in which the upstream grooves and the screen passage channels are formed from a stainless steel sheet in a screen wall that is rotationally symmetrical to the screen axis.
  • a screen with the features set out above is e.g. B. from Fig. 2a of U.S. Patent 4,529,520.
  • grooves on the inflow sides of pressure sorter screens contoured by grooves are shown, the screen passage channels of which are parallel slits running to the sieve axis and radially flowed through with respect to the latter and their grooves also run parallel to the sieve axis and have a V-shaped cross section perpendicular to the sieve axis, the bisector of which is radial with respect to the sieve axis, the slit-shaped sieve passage channels either being exactly in the groove ⁇ open out or in front or in the rotor rotation direction eren side wall, approximately halfway up the respective side wall.
  • the two groove side walls are each inclined at an angle of 45 ° with respect to the direction of the wire circumference, so that they form an angle of 90 ° with one another.
  • the groove depth is 1 mm, the groove width measured in the circumferential direction of the sieve is consequently 2 mm.
  • those screens made by Hermann Finckh Maschinenfabrik GmbH & Co. have proven particularly effective which have a screen wall made of a stainless steel sheet that is rotationally symmetrical with respect to the screen axis and which are consecutive and approximate on their upstream side in the circumferential direction of the screen
  • the grooves are between 0.8 mm and 1.0 mm deep (for the sorting of fiber suspensions with a majority of relatively short fibers, a smaller groove depth has proven advantageous, for long fibers one greater groove depth).
  • On the inflow side of the sieve there is provided in the circumferential direction between successive grooves in each case a substantially flat surface area which is at least approximately parallel to the circumferential direction of the sieve and whose width measured in the circumferential direction of the sieve is 0.5 mm. This profiling of the upstream side of the screen has proven itself for the following reasons:
  • the fiber suspension to be sorted is placed on the upstream side of the sieve with the help of the rotor in its Direction of rotation is accelerated and driven, and by appropriate profiling of the rotor peripheral surface, positive and negative pressure surges are generated in the fiber suspension to be sorted. Due to the negative pressure surges, liquid is sucked back and forth from the part of the fiber suspension that has already passed through the sieve through the sieve passage channels to the upstream side of the sieve, whereby the sieve passage channels are rinsed and blockages are prevented.
  • Turbulence is generated in the fiber suspension still flowing along the upstream side of the sieve, which is still to be sorted, due to which the grooves prevent the upstream side of the sieve a nonwoven fabric which reduces the throughput of the pressure sorter can be formed, by means of which even useful fibers would be retained. Turbulence that is sufficiently strong for this purpose, however, requires a certain minimum depth of the said grooves.
  • the first front groove side walls in the direction of rotation of the fiber suspension to be sorted are responsible for the formation of this turbulence; These produce a negative pressure in the fiber suspension, which is still to be sorted and flows essentially along the circumferential direction of the screen in the area of the respective front groove side wall, the greater the steeper this front groove side wall, i.e. the more it (on average perpendicular to the sieve axis) is inclined with respect to the direction of the circumference of the sieve.
  • a high vacuum of this type naturally leads to a reduction in the throughput of the pressure sorter.
  • an abrasive wear on the screen on the upstream side also plays a significant role: especially fiber suspensions obtained from waste paper contain many types of abrasive components such as sand, metallic components originating from wires, paper clips and the like and the like.
  • abrasive wear on the upstream side of the screen has progressed, the smaller the depth of the grooves and the weaker the turbulence which is essential for keeping the screen passage channels free. For this reason too, the grooves must be made with a certain minimum depth.
  • the invention was based on the object of creating a screen which has turbulence-generating grooves on its upstream side, such as the screen described above by Hermann Finckh Maschinenfabrik GmbH & Co., with which a higher throughput can be achieved without the inter alia to impair the durability or service life of the sieve, depending on its wear behavior.
  • this known sieve has two serious disadvantages: the flat groove bottom forming the groove base, in conjunction with an indispensable minimum depth of the groove, leads to a relatively large sieve division and thus to a relatively small free passage area of the sieve, and the front groove side wall perpendicular to the direction of the sieve circumference has the result that in the region of the groove base and thus in the region of the mouth of the sieve passage channel there is a comparatively large negative pressure which reduces the throughput of the pressure sorter.
  • the sieve passage channels are not necessarily exactly in the groove base, i.e. H. must open into the tip of the approximately V-shaped groove cross section, but can also be offset somewhat upstream relative to the groove bottom, d. H. can open into the lower quarter or lower third of the front groove side wall without having to accept major disadvantages, as would be the case if the screen passage channels would open into the rear groove side wall (risk of the screen passage channels becoming blocked) or further would open at the top into the front groove side wall (shorter service life of the sieve, because then through an abrasive wear on the upstream side of the sieve, the openings of the sieve through channels would quickly come closer to the upstream side of the sieve and the screen would soon tend to clog its through channels) .
  • the properties of the sieve according to the invention with regard to the throughput that can be achieved and its operating behavior can be started from the one described above
  • the basic idea of the invention is that the more the inclination of the front groove side wall approaches an angle of approximately 52 ° or approximately 53 ° with respect to the circumferential direction of the sieve, and an optimum results at an inclination angle of 37.5 ° especially when the sieve outlet channel opens exactly in the groove base and flows through radially with respect to the sieve axis.
  • an essentially flat surface area is provided which is at least approximately parallel to the circumferential direction whose width measured in the circumferential direction preferably corresponds to approximately 20% to approximately 30% of the groove width, and a width of this surface area which has been found to be particularly advantageous is approximately equal to 1/5 of the groove width.
  • the sieve passage channels can also be bores with a consequent circular cross section and then several such bores can open into each of the upstream grooves, which are located one behind the other in directions approximately parallel to the sieve axis and z.
  • the sieve passage channels have the shape of slots which (viewed on the upstream side of the sieve) extend approximately parallel to the sieve axis, because with such slits sieves with a larger free passage area and thus pressure sorter with a higher throughput.
  • the sieve wall is as strong as possible so that only a single sieve passage channel opens into each of the upstream grooves, because then the upstream grooves (in the direction of the sieve axis measured) or not (for manufacturing reasons) only insignificantly longer than the slots forming the screen passage channels.
  • the grooves form a plurality of groove rows which extend in the circumferential direction of the sieve and are spaced apart in the direction of the sieve axis.
  • the upstream grooves could be produced using any known processing technique, e.g. B. by evaporating the metal in the area of the grooves to be produced by means of an energy beam (laser or electron beam) (the sieve passage channels could also be produced with such an energy beam), it is recommended in the current state of the art, for reasons of production costs and the precision of the contours to be produced in the screen wall to form the grooves as recesses produced by machining, so that they can be produced in particular by means of a form cutter.
  • an energy beam laser or electron beam
  • the sieve wall of which is made of sheet steel for the sieve wall - outside the sieve openings connecting the inflow side to the outflow side - a wall thickness of approximately 6 mm to approximately 10 mm and in particular from about 6 mm to about 8 mm.
  • preferred embodiments of the sieve according to the invention as well as a large number of known pressure sorter sieves have depressions on their outflow sides, each of which has at least one Sieve passage opens; These depressions preferably also have the shape of grooves running approximately parallel to the sieve axis, and as can be seen from the above, it is particularly advantageous in the case of a sieve with slot-shaped sieve passage channels if only one sieve passage channel is located in each of these outflow-side depressions flows.
  • the subject of the invention is also a pressure sorter of the type disclosed and claimed in WO 94/00634, the screen of which is designed in accordance with the present invention, since it has been shown that a screen according to the invention is connected with a pressure sorter, the rotor of which is designed in the manner disclosed and claimed in WO 94/00634, leads to particularly good results.
  • FIG. 1 shows a partially sectioned side view of the pressure sorter according to the invention, the section being a section in a vertical diameter plane of the rotor or sieve;
  • Figure 2 is a section along the line 2-2 in Fig. 1.
  • FIG. 4 shows an end view of the rotor, seen from the left in accordance with FIG. 1, specifically with the sieve shown in an axial section;
  • FIG. 5 shows a development of the rotor circumference, i.e. a plan view of the entire rotor circumferential surface, which was, however, shown in one plane;
  • FIG. 6 shows a section through a preferred embodiment of the sieve according to the invention along a diameter plane containing the axis 34, which also represents the sieve axis (however, the details visible in a view of the upstream side of the sieve have been omitted in FIG. 6 for the sake of simplicity sen); 7 shows the detail "X" from FIG. 6 on a larger scale or a section along the line 7-7 in FIG. 8;
  • FIG. 9 shows a section through part of the screen wall according to line 9-9 in FIG. 8.
  • the actual pressure sorter 10 shown in FIG. 1 with a housing 14 standing on supports 12 also includes a motor 18 standing on a frame 16, which is a three-phase or three-phase alternating current motor, which is operated by means of a pulley 20 and V-belt 22 drives a pulley 24, which is fastened on a rotor shaft 26 rotatably mounted in the frame 16 and the housing 14.
  • a motor 18 standing on a frame 16 which is a three-phase or three-phase alternating current motor, which is operated by means of a pulley 20 and V-belt 22 drives a pulley 24, which is fastened on a rotor shaft 26 rotatably mounted in the frame 16 and the housing 14.
  • the housing 14 essentially consists of a left end wall 28 according to FIG. 1, a circular cylindrical housing jacket 30 arranged concentrically to the rotor shaft 26 and a housing cover 32 which are connected to one another in a pressure-tight manner.
  • the rotor shaft 26 which is passed through the end wall 28 in a pressure-tight manner, carries a rotor, designated as a whole by 36, which can be driven about the axis 34 by means of the rotor shaft 26 and is surrounded by a circular cylindrical sieve 38 concentric to the axis 34. which is fastened to two annular housing elements 40 and 42 fastened to the housing shell 30 and is thus held by these housing rings.
  • the axial length (in the direction of the axis 34) of the rotor 36 is equal to the axial length of the effective area of the sieve 38 between the housing rings 40 and 42.
  • an inlet connection 46 is provided, through which - as indicated by the arrow F - the fiber suspension to be processed or sorted is conveyed into the pressure sorter, by means of one not shown pump.
  • an outlet connection 48 is attached to the housing jacket 30, through which the so-called accept material - as indicated by the arrow A - leaves the pressure sorter.
  • the good substance is the part of the fiber suspension which has passed the sieve 38.
  • a second outlet connection 50 is finally fastened, through which the so-called rejects - as indicated by the arrow R in FIG. 2 - leaves the pressure sorter; the reject material is the part of the fiber suspension to be processed which cannot pass through the sieve 38.
  • the fiber suspension to be sorted flows approximately tangentially into the housing 14, just as the outlet nozzle 50 for the rejects is oriented tangentially (see FIG. 2).
  • the outlet connection 48 could of course also be arranged at the bottom of the housing jacket 30, insofar as the installation of the pressure sorter 10 permits the removal of the accepted substance downwards.
  • the fiber suspension to be processed which is fed into the pressure sorter 10 via an inlet connection 46, first arrives in an inlet space 52 and then enters an annular space between the circumference of the rotor 36 and the sieve 38, which is referred to below as the inlet space 54, and the fiber suspension to be sorted enters the latter via a first axial end 54a of this inlet space.
  • the fiber suspension flows helically through the inlet space 54 from the latter the first end 54a to the second end 54b, a part of the fiber suspension passing through openings in the sieve 38 and thus entering the accepting material space 58.
  • the reject leaves the inlet space 54 at its second end 54b and thus reaches the reject space 56, from which the reject leaves the pressure sorter via the second outlet connection 50.
  • the axis 34 runs at least approximately horizontally, but in principle it would also be conceivable to set up the pressure sorter in such a way that its axis 34 runs at least approximately vertically.
  • a measuring device 60 which comprises a first pressure transmitter 62 and a second pressure transmitter 64, which are located in the inlet connection 46 or in the first outlet inlet nozzle 48 are arranged, but could also be arranged in the inlet space 52 or in the accept material space 58.
  • a difference former 74 which delivers at its output a control signal proportional to the pressure difference, which is applied via line 76 to the control input of a frequency converter 78.
  • This is fed from a current source (not shown) with a 3-phase alternating current or three-phase current of the frequency f ⁇ and supplies a three-phase current of the frequency f ⁇ for driving the three-phase motor 18, the frequency f ⁇ being a function of the control signal generated by the difference generator 74 is.
  • the rotor 36 is driven at a speed which is a function of this control signal and thus the pressure difference between the inlet space 54 and the accept material space 58.
  • potentiometers or other actuating elements could also be provided in the lines 66 and 68, with which the signals supplied by the pressure transmitters 62 and 64 could be changed, so that the dependency on the line 76 to be able to influence the control signal present from the pressure difference mentioned.
  • a hub 80 which is fixedly connected to the rotor shaft 26 carries a closed, hollow circular cylindrical rotor body 82 with a circular cylindrical rotor jacket 84.
  • This has a first axial end 84a at the first axial end 54a of the inlet space 54 and a second axial end 84b at the second axial end 54b of the inlet space and carries two sets of profile elements on the outside, namely a first set, which of Profile elements 86a, 86b, 86c and 86d is formed, and a second set, formed by profile elements 88a, 88b, 88c and 88d.
  • the first set of profile elements forms a first row of profile elements extending in the rotor circumferential direction or direction of rotation U of the rotor and gaps 86a ', 86b', 86c 'and 86d' arranged between them, and this row defines a first axial rotor section 90 which faces the inlet space 52;
  • the second set of profile elements 88a-88d forms a second, just such a row of profile elements and gaps 88a ', 88b', 88c 'and 88d' arranged between them, and this second row defines a second axial rotor section 92, which is adjacent to the reject space 56 is.
  • all profile elements are of the same height (measured in the direction of the axis 34), but depending on the desired sorting result and / or depending on the type of fiber suspension to be sorted, it could be expedient to increase the height of the first row or to be chosen smaller than the height of the second row. It may also be expedient to provide the rotor with more than two such rows.
  • each profile element has a front face or front flank I lying in the direction of rotation U, which is perpendicular to the circular-cylindrical outer circumferential surface of the rotor shell 84 and thus to the area of the gap in front of it in the direction of rotation U. runs, as well as a back surface directly adjoining the first flank I or second flank II, which drops inward in the radial direction counter to the direction of rotation U and thus towards the axis 34, so that the profile elements in section perpendicular to the axis 34 have a cross section which resembles a very acute-angled triangle which was bent concentrically to the axis 34.
  • the first flanks I generate strong positive pressure surges and strong turbulence in the inflow space 54, and the fiber flanks in the inflow space 54 are also greatly accelerated with the first flanks I, up to the maximum speed of the profile elements.
  • the falling second flanks II generate negative pressure impulses, by means of which liquid is sucked back from the accept substance space 58 through the sieve openings into the inlet space 54.
  • Particularly strong turbulence results in the inlet space 54 as a result of the flow component of the fiber suspension directed in the direction of rotation U when the inside of the sieve 38 is “rough” according to the invention, ie is profiled.
  • the first flanks I do not run parallel to the axis 34, but form an acute angle ⁇ with the direction of the axis 34, specifically the flanks I are inclined with respect to the direction of the axis 34 so that the flow component of the fiber suspension running in the direction of the axis 34 is strengthened in the inlet space 54 in the direction from the first axial end 54a of the inlet space to its second axial end 54b.
  • the profile elements 86a-86d of the first row - measured in the rotor circumferential direction or direction of rotation U - are shorter than the profile elements 88a-88d of the second row.
  • This measure serves the purpose of adapting the effect of the profile elements to the different consistency of the fiber suspension, the consistency of which increases in the inlet space 54 from its first end 54a to its second end 54b.
  • each of the profile elements extends 86a-86d of the first row over a circumferential angle of 45 ° (this is the maximum length L ⁇ - of the profile elements), the length of the profile elements to the second axial end 84b of the rotor shell 84 decreasing because the first flanks I are oblique to the direction of the axis 34 run, while the rear edges of the second flanks II are aligned parallel to the axis 34.
  • the smallest length L ⁇ 'of the gaps 86a' - 86d 'of the first row is also 45 ° and is therefore equal to the greatest length L ⁇ of the profile elements of this row, the length of the gaps in the direction of the second axial end 84b of the rotor shell 84 increases.
  • the maximum length L2 of the profile elements 88a-88d of the second row is 53 ° in this embodiment; since the number of profile elements of the second row is equal to the number of profile elements of the first row, the minimum length L2 'of the gaps 88a' - 88d 'of the second row results in a lower value of 37 ° here.
  • the profile elements 88a-88d of the second row and thus their gaps are offset relative to the profile elements of the first row or their gaps against the direction of rotation U, the size of the offset thus being equal to the lengths of the Profile elements or the gaps is coordinated so that gaps of the two rows adjacent to one another in the axial direction overlap in the direction of rotation U or in the rotor circumferential direction to such an extent that they form a continuous channel in the axial direction which extends from one axial end 84a of the Rotor shell 84 extends to the other axial end 84b.
  • FIG. 1 the profile elements 88a-88d of the second row and thus their gaps are offset relative to the profile elements of the first row or their gaps against the direction of rotation U, the size of the offset thus being equal to the lengths of the Profile elements or the gaps is coordinated so that gaps of the two rows adjacent to one another in the axial direction overlap in the direction of rotation U or in the rotor circumferential direction to such an extent that they form a continuous channel in the axial direction which extends
  • the inside width L3 of this channel is 25 °, the inside width being understood as the width which the observer sees in the direction of the axis 34 when the rotor is viewed from the front.
  • the lengths of the profile elements of the first row are therefore approximately equal to the lengths of the gaps of the first row
  • the lengths of the profile elements of the second row are greater than the lengths of the profile elements of the first row
  • the lengths of the gaps of the second row are smaller than the lengths of the profile elements in the second row and smaller than the lengths of the gaps in the first row.
  • steps 90 by which the following effect is achieved: accumulations of fibers and impurities which can occur on the first flanks I of the profile elements 86a-86d of the first row , slide on account of the axial flow component of the fiber suspension in the inlet space 54 along the first flanks I of the profile elements of the first row in the direction of the second axial end 54b of the inlet space 54 and thus reach the steps 90, in the area of which they are due to the strong turbulence prevailing there are dissolved and mixed with the fiber suspension - accumulations of fibers and impurities on the first flanks I of the profile elements 88a-88d of the second row are likewise transported in the axial direction and reach the reject space 56.
  • the lengths of the profile elements and the gaps were expressed in circumferential angles above.
  • the lengths L and L are in a range between approximately 200 mm and approximately 450 mm.
  • the circumferential speeds of the rotor achieved by adjusting the rotor speed are expediently between approximately 10 m / s and approximately 40 m / s, the best sorting results generally being achieved with peripheral speeds of approximately 15 to approximately 30 m / s.
  • the sieve openings 38a of the sieve 38 are bores, their diameter is expediently approximately 1 mm to approximately 3.5 mm if the rotor has a peripheral speed of approximately 10 to approximately 15 m / s is operated. Smaller holes can be used at higher peripheral speeds; It is expedient to operate a pressure sorter according to the invention with circumferential rotor speeds of approximately 15 to approximately 40 m / s and then select bores with a diameter of approximately 0.5 to approximately 1.5 mm for the sieve openings.
  • the screen openings 38a are slits, these should have a width of approximately 0.4 to approximately 0.6 mm at circumferential rotor speeds of approximately 10 to approximately 15 m / s; Even in the case of slots, finer screen openings can be used at higher rotor peripheral speeds, and since rotor peripheral speeds of approximately 15 to approximately 40 m / s are preferred, slot-shaped screen openings with a width of approximately 0.1 mm to approximately 0.35 mm recommended.
  • each of these profile elements - apart from the rotor casing 84 - consists of a strip 100 forming the first flank I, a bent sheet metal 102 forming the second flank II and two side walls 104, reference being made to this with reference to FIG. 3, that in this figure, because of the oblique course of the first flanks I and thus the strips 100, the latter were not cut perpendicular to their longitudinal extension, but rather obliquely thereto.
  • the cavities 106 of the profile elements enclosed by the rotor jacket 84, the strips 100, the sheets 102 and the side walls 104 should be liquid-tight or filled with a filler, such as a foam plastic, in order to avoid the occurrence of imbalances in the rotor .
  • a filler such as a foam plastic
  • the design and arrangement of the sieve openings 38a according to the invention are now to be explained in more detail with reference to FIGS. 7-9 and in particular with reference to FIG. 9.
  • the sieve wall 300 has been drawn in a flat, flat state in FIG. B. in the state in which the sieve wall 300 made of stainless steel sheet is during processing and before bending and welding to form a circular cylinder.
  • each of the sieve openings 38a consists of four components ten, which partially overlap each other, namely from three grooves and a slot.
  • an inlet-side groove 400 was milled out of the sheet metal forming the sieve wall 300 for each sieve opening 38a, first an inner groove 402 and then an outer groove 404 from the outflow side 308, the opening angle of which is greater than that of the inner one Groove 402.
  • a slot was then finally sawn into the sieve wall 300, which forms a sieve passage channel 406 connecting the grooves 400 and 402 to one another.
  • each sieve opening 38a is arranged relative to one another such that, after the sieve wall 300 has been bent into a circular cylindrical sieve 38, they all lie on a diameter plane 408 containing the sieve axis 34 - this diameter plane therefore represents the central plane of the slot-shaped sieve passage channel 406, as well the central planes of the grooves 402 and 404, which are designed symmetrically to this diameter plane 408, and finally the base of the groove 400 also lies on the diameter plane 408.
  • the total thickness of the sieve wall is approximately 6 mm
  • the depth of the groove 400 measured perpendicular to the inflow side 306 is 1 mm
  • the distance between the bottom of the groove 402 just formed and the downstream side 308 is 4 mm
  • the groove 404 should be 0.72 mm deep.
  • the opening angle (measured in the drawing plane of FIG. 9) of the inner groove 402 should be 16 °, that of the outer groove 404 120 °. It follows from this that, measured on the outflow side 308, the width of the outer groove 404 measured in the circumferential direction of the sieve is 2.5 mm.
  • the width (also called the slot width) of the slot-shaped sieve passage 406 measured in the same direction depends on the desired fineness of the sieve and is in particular 0.1 mm to 0.25 mm.
  • the direction of rotation or rotation of the rotor 36 has been designated by "U”, and in this direction the screen on its upstream side 306 has two surface areas 410 between two successive grooves 400, which surface area has a screen wall bent into a circular cylinder 300 is part of a circular cylindrical surface and its width measured in the screen circumference or rotor rotation direction U in the preferred embodiment shown should be 0.5 mm.
  • each of the grooves 400 now has a steeper front groove side wall 400a and a flatter rear groove side wall 400b, which in the preferred embodiment shown form an angle of 97.5 ° with one another, while the angle ⁇ between the front groove side wall 400a and the diameter plane 408 is 37.5 °, the angle ⁇ between the diameter plane 408 and the rear groove side wall 400b is 60 °.
  • a depth of the groove 400 of 1 mm this results in a width of the groove 400 of 2.5 mm, measured in the direction of rotation U of the rotor.
  • the angle by which the front groove side wall 400a is inclined with respect to the circumferential direction of the screen or the direction of rotation U of the rotor is 52.5 °
  • the angle of inclination of the rear side wall 400b with respect to the circumferential direction of the screen is 30 °.
  • the "boat-shaped" shape of the grooves 400 which can be seen in FIG. 8 (the same applies to the other grooves 404 and 402) is merely a consequence of the way in which the grooves are produced by means of circular disk-shaped cutters and at least essentially without the function of the sieve according to the invention Matter.
  • the relatively steep front groove side walls 400a lead to the fact that relatively strong turbulence is generated in the grooves 400, a certain negative pressure is created in the vicinity of the front groove side walls 400a and the flow essentially in the direction of rotation U of the rotor Fiber suspension is sucked into the grooves 400; Parts of the fiber suspension flow impinging on the rear groove side walls 400b are "reflected" back into the inlet space 54 by these groove side walls 400b, ie deflected into the fiber suspension adjacent to the upstream side 306 and thus prevent them from being sorted in the one to be sorted Fiber suspension, which is adjacent to the upstream side 306 of the sieve, can form a nonwoven fabric which reduces the throughput of the pressure sorter.
  • the static pressure prevailing in the inlet space 54 in the fiber suspension to be sorted is greater than the static pressure in the accepting material space 58, the pressure drop across the sieve wall 300 already leads to that part of the fiber suspension to be sorted which can pass through the sieve passage channels 406, flows into the sieve passage channels from the upstream side 306; this process is supported by the positive pressure surges generated by the rotor 36 in the fiber suspension to be sorted.
  • this has a pitch of 3 mm compared to a pitch of 4 mm of a sieve which differs from the sieve shown in FIG. 9 only in that not only the angle ⁇ , but also the angle ⁇ is 60 °, the opening angle of the grooves 400 is 120 °.
  • the smaller division results in an approximately 1/3 larger free passage area of the sieve, and surprisingly, a sieve according to the invention leads to an increase in throughput rate at least in proportion to the increase in the free passage area, although the front groove side walls 400a are steeper than in the known sieve from Hermann Finckh Maschinenfabrik GmbH & Co. described above, with upstream grooves formed symmetrically to the diameter planes 408 with an opening angle of 120 °.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Paper (AREA)
  • Nonwoven Fabrics (AREA)

Abstract

Un crible (38) de triage de suspensions de fibres est symétrique par rapport à un axe (34), comprend un côté d'admission (306) de la suspension de fibres à trier et un côté d'écoulement (308) opposé au côté d'admission (306). Ce crible (38) est utilisé dans des trieuses sous pression qui comprennent un rotor (36) mis en rotation autour de l'axe du crible et pourvu d'éléments profilés situés tout autour du côté d'admission du crible afin de générer des impulsions de pression positives et négatives dans la suspension de fibres à trier. Le côté d'admission (306) du crible est pourvu de rainures (400) à peu près parallèles à l'axe du crible qui se suivent dans le sens de la circonférence du crible. Au moins un canal de passage (406) débouche dans chaque rainure. Les rainures sont délimitées chacune par une paroi latérale antérieure et par une paroi latérale postérieure (400a, 400b), vues dans le sens de rotation des éléments profilés. Afin d'augmenter la capacité de la trieuse sous pression, les rainures (400) ont une section transversale à peu près en V, dans une coupe perpendiculaire à l'axe du crible, et la paroi latérale antérieure (400a) des rainures forme avec la circonférence du crible un angle d'environ 40 DEG à environ 70 DEG .
EP95907639A 1995-02-03 1995-02-03 Trieuse sous pression de suspensions de fibres et crible pour ces trieuses sous pression Expired - Lifetime EP0805890B1 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
AT95907639T ATE181120T1 (de) 1995-02-03 1995-02-03 Drucksortierer zum sortieren von fasersuspensionen sowie sieb für einen solchen drucksortierer
EP98122514A EP0905309B1 (fr) 1995-02-03 1995-02-03 Tamis et appareil de tamisage sous pression pour suspensions fibreuses

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
EP98122514A EP0905309B1 (fr) 1995-02-03 1995-02-03 Tamis et appareil de tamisage sous pression pour suspensions fibreuses
PCT/EP1995/000388 WO1996023930A1 (fr) 1995-02-03 1995-02-03 Trieuse sous pression de suspensions de fibres et crible pour ces trieuses sous pression

Related Child Applications (1)

Application Number Title Priority Date Filing Date
EP98122514A Division EP0905309B1 (fr) 1995-02-03 1995-02-03 Tamis et appareil de tamisage sous pression pour suspensions fibreuses

Publications (2)

Publication Number Publication Date
EP0805890A1 true EP0805890A1 (fr) 1997-11-12
EP0805890B1 EP0805890B1 (fr) 1999-06-09

Family

ID=8165950

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EP95907639A Expired - Lifetime EP0805890B1 (fr) 1995-02-03 1995-02-03 Trieuse sous pression de suspensions de fibres et crible pour ces trieuses sous pression

Country Status (6)

Country Link
US (1) US6029825A (fr)
EP (1) EP0805890B1 (fr)
CA (1) CA2210877C (fr)
DE (1) DE59506189D1 (fr)
FI (1) FI973189A0 (fr)
WO (1) WO1996023930A1 (fr)

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4048258B2 (ja) * 1998-02-03 2008-02-20 株式会社Ｉｈｉ 古紙パルプの選別装置
WO1999046026A1 (fr) * 1998-03-11 1999-09-16 Thermo Black Clawson Inc. Epuration a pression variable
CA2403127A1 (fr) * 2000-02-19 2002-10-11 Voith Finckh Fiber Systems Gmbh & Co. Kg Tamis pour suspensions de fibres et son procede de production
SE537441C2 (sv) * 2013-08-29 2015-04-28 Bomill Ab Trumma, en maskin som innefattar en sådan trumma, och ett förfarande för tillverkning av en sådan trumma
CN113550705B (zh) * 2021-09-23 2021-12-28 西南石油大学 一种脉冲负压钻井振动筛

Family Cites Families (8)

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Publication number Priority date Publication date Assignee Title
SE427124B (sv) * 1980-01-28 1983-03-07 Celleco Ab Anordning for silning av fibermassasuspensioner
FI67588C (fi) * 1983-01-26 1985-04-10 Ahlstroem Oy Silplaot
DE3572928D1 (en) * 1984-12-25 1989-10-19 Mitsubishi Heavy Ind Ltd Pressure slit screen
FI882569A (fi) * 1987-06-11 1988-12-12 Ahlstroem Oy Sil.
DE3816152A1 (de) * 1987-11-14 1989-11-23 Voith Gmbh J M Siebkorb und verfahren zu dessen herstellung
DE4121896A1 (de) * 1991-07-02 1993-01-07 Fiedler Heinrich Gmbh Siebelement
DE9108129U1 (de) * 1991-07-02 1991-09-05 Heinrich Fiedler GmbH & Co. KG, 8400 Regensburg Siebelement
JP3542594B2 (ja) * 1992-06-20 2004-07-14 ボイト フィンク ファイバー システムズ ゲゼルシャフト ミット ベシュレンクテル ハフツング ウント コンパニー コマンディト ゲゼルシャフト 繊維懸濁液用加圧分離装置

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO9623930A1 *

Also Published As

Publication number Publication date
US6029825A (en) 2000-02-29
CA2210877A1 (fr) 1996-08-08
WO1996023930A1 (fr) 1996-08-08
FI973189A (fi) 1997-08-01
EP0805890B1 (fr) 1999-06-09
DE59506189D1 (de) 1999-07-15
CA2210877C (fr) 1999-12-21
FI973189A0 (fi) 1997-08-01

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