A CLEANING PROCEDURE AND APPARATUS

Abstract: A cleaning procedure relates to cleaning of clogged holes or passages of lesser diameter, such as deep through-holes or through-holes with light of varying sizes, in particular such holes in dies for through-pressing of materials at the manufacturing of pellets, as in particular dies employed at pelletizing of feedstuff pellets. By means of the procedure a comparatively fast cleaning is obtainable without any particular damaging of the material of the walls of the holes. A control procedure for a fast-operating cleaning means is described. As fast-operating cleaning means a fast-emitted, possibly with supersonic speed emitted, thin water jet is applicable. An apparatus to be used together with the procedure is described. By means hereof it is possible to clean radially oriented holes or passages in a die (1) for pelletizing by means of a water jet emitted from a nozzle (2A) under a very high pressure.

Description: A cleaning procedure and apparatus. The present invention relates tσ a cleaning procedure and an apparatus -for cleaning of clogged holes or passages of lesser diameter, such as through—holes or through—holes with light of varying sizes, in particular such holes in dies provided with a large amount of such holes for through-pressing of materials at the manu acturing of pellets, such as dies employed at pelletizing of feed stuff pellets. Without limiting the invention to dies for pelleti¬ zing of feed pellets, in the following the invention is described mainly under reference as being employed to dies of that kind. Such dies for pelletizing may be embodied with a length in a>:ial direction of .15 through .25 m and a dia¬ meter of about .4 through .6 being made as cylindric elements of steel with a material thickness of about .05 through .15 provided in radial direction with a large amount of drilled through—holes or passages exhibiting each a light of about 1.3 through 10 mm. Generally, the holes or the passages are drilled, as from the periphery of the cylindric elements by means of a precisely guided drilling machinery, with the holes being distributed so that the holes are spaced mutually with the spcaing be- tween them being about two to three times their light dia¬ meters, and whereby the holes are distributed in a forma¬ tion ringwise encircling the cylindric periphery of the die elements, i.e. comprising in total some hundred holes contained within each of 20 through 45" ringwise formations encircling the single elements. The dies are employed for pelleting, most often in the manner, that two or three cy¬ lindric rolls at distances of about .5 through 1 mm are rolling against the internal surfaces of the cylindric dies. A material to be pelleted, i.e. a feed stuff powder, is supplied to the spacing between the rolls and the inner surface of the die. By means of great pressure the powder is pressed through the single die holes and is shaped into thin bars, which by means of suitable cutting means are cut into suitable lengths at the outer side of the die. Through a die of the aforementioned size, which for in¬ stance comprises 10,000 holes, with a light diameter each of about 3 mm, 5 to 10 t of feed stuff may be passing per hour, i.e. per hour a considerable amount of material. But, experience shows that in course of time unavoid- ably more and more of the holes become clogged involving a decline in the production which through not further speci¬ fied reasons by itself results in unwanted halts in the production, whereby halts in the production by themselves may cause a clogging of holes in the dies. But, much clog- ging of the holes is caused by small pieces of metal which in one way or another is present in the feed stuff mixtu¬ res. But, partially clogged peripheral portions of the dies may be caused by erroneous feed stuff mixtures or through a wear—down of counter sunk input ends of the die holes, which counter sinking was provided at the manufac¬ ture of the dies. Clogging may also be the result of a de¬ forming of the feed stuff input ends of the holes by the pressing rolls due to too large pressure being provided by them when they during manufacturing of feed stuff pellets are pressing against the inner side of the dies, etc. Dies causing reduced production have to be exchanged with dies giving optimum of production. As the dies are rather ex¬ pensive it is wanted to get them restored. Unto now this has been provided by means of a simple drilling process taking place by means of manually guided drilling machi¬ nes, as this manner of restoring the dies is more effici¬ ent than using a pillar drill because pillar drills leave more broken drills sticking unremovably in the die holes as compared to a manual restoring procedure. When employ- ing the dies for pelletizing the. single holes suffers a wear-down providing them with a conical shape having the largest light diameters at the feed stuff material input end of the holes. The manual drilling procedure is rather slow. As the dies are expensive it nevertheless pays off. In this respect it should be noticed that the problem exists to avoid a deteriorating of the shape of the holes during restoring the dies, because it is important to get the internal surfaces of the holes as even as possible. This has shown itself to be difficult. When putting the dies to operation a suitable hole polishing means often has been brought first to pass through the dies, or a feed stuff mixture with such properties is at first let through the die holes when restoring the operation of the dies. To clean the dies manual washing has been tried, but, SD strong force is required applied to the washing water that a washing water jet is not controllable. Experience has on the other hand shown, if very large water pressures are used, i.e. larger than 400 b, then it is possible to achieve an effective cleaning of such clog¬ ged holes so that few or practically none remain clogged. To achieve a sufficiently cheap restoring of the dies a high degree of mechanizing has to be attained because it is not possible while cleaning optically to attain a sa¬ tisfactory positioning of such powerful water jet towards a hole to be cleaned. Moreover, as little span of time as possible has to be used for the positioning of the water jet towards a hole to be cleaned, but, such water jet has the tendency to be positionally locked somewhere along its path when moved, because it has the same inherent capacity as a broad jet of water which directed upwards from below is able to carry, as rotational objects shaped, bodies, such as evenly shaped balls. It must be admitted that the first trials of handling such a powerful water jet were more or less blindfolded carried out, but, trials with a fast positioning and to the purpose suitable fast position adjusting and in general by one step right-position-acqui¬ ring moving around of the water jet show that it without damaging the steel material of the die which steel mate¬ rial is hardened steel material is possible to move or displace a thin water jet of this kind from one hole to a neighbouring hole for the cleaning hereof. If the displacing is too short the water jet shows a tendency to be locked in position at the middle Df the ma¬ terial wall between the two holes. On the other hand, if the hole sufficiently fast is hit the water jet will lock to the middle of the hole. This locking is due to the returning water from the spot being met by the jet. It has later been found, that a cleaning is achieved if a water jet of the mentioned pressure has a suitable small diame¬ ter, which is somewhat less than the diameter of the hole, with an optimum hereof being approximately half the dia e- ter of the hole. The jet thus has to keep itself locked to the hole being cleaned, also in case this hole is able to be cleaned only for a fraction of its length. On the other hand, a very high water pressure is required. Holes which are clogged with feed stuff are fairly fast becoming clea- ned with the feed stuff bulletlike leaving the hole. Seve¬ rely clogged holes may require more seconds with water jet treatment before a cleaning is attained. Experience shows that the thin cutting jet apparently does nσt damage the die material. On the other hand, the energy supplied to the water jet and to the maintaining of it is considerable, i.e. 50 through 75 kw are required for a 1 through 3 mm thick water jet, resulting in powerful heating of the water. Wherefore, the water before it pos¬ sibly for reuse is led to a storage tank has to be cooled. According to the invention, summarizing, the procedu¬ re for cleaning of holes as specified in the introduction thus can be characterized through the following procedure steps, whereby clogged objects with clogged holes to be cleaned are specified as dies, and in that the die is located on a suitable supporting means comprising holding means for the fastening of the die in relation to a water jet means, whereby these said holding means comprises ac- tivatable position adjusting means for adjusting or readjusting the said fastened mutually fixedly holding which fastening to a lesser degree, possibly by means of a minor flexibility and/or spring induced flexibility, only is to be characterizable as a limited fastening, and in that with an accuracy being of the size being within the half of the smallest hole diameter or better a water jet with a diameter being of the size less than the half of the smallest hole diameter is directed against the first hole to be cleaned having the direction of the longitudi¬ nal orientation of the hole, and in that the degree of mutual fixation between the mentioned elements is main¬ tained to such a degree so that approximately the flexibi¬ lity of the fixation permits relatively a mutual moving between these said elements to be less than the said half hole diameter of the smallest hole in the die to be cleaned, and in that a behind the hole arranged detecting means detecε the arrival of water respectively of clogged material from the rear end of the hole and activates memo- ry means resulting in either stop of cleaning operation or in mutual displacing taking place through activation of the said position adjusting or readjusting means for the die/water jet with a mutual displacing corresponding to the mutual spacing between the centre of the cleaned hole and the centre of the next hole to be cleaned with an accuracy of the displacing being better than the half of the smallest hole diameter and with the water jet being directed towards this opening oriented in the longitudinal direction of the hole, and whereby the procedure continues as described above at "and in that the degree of mutual fixation between the mentioned elements is ......". It is understood that other kinds of media than water may be used for the jet, to be understood as well in the above mentioned as in that which follows hereinafter. The procedure has furthermore to be thus understood that in principle the water jet may be exchanged with a drilling means, and in that those steps of the procedure which thus are influenced herethrough may be carried out as the first respectively as the last steps of the proce¬ dure. According to the invention it is thus foreseen that procedure steps may be applied to the procedure by which the water jet is substituted with a drilling or cleaning means which solely is able to perform cleaning of the area at one end of the holes, and whereby the detecting means is provided able to detect termining cleaning of the single areas of these ends of the holes. It is to be noticed, that these procedure steps as well may relate to cleaning of the same end, as respecti¬ vely of the opposite end, of the holes to be cleaned through the use of the invention. It is alsσ according to the invention foreseen, that the cleaning water jet may be provided able to clean in a usual direction as well as in the opposite direction through the holes. This facility is described more closely as follows later. Furthermore, it is to be noticed, that according to the invention it is foreseen that the cleaning water jet under an extremely high pressure is emitted from a nozzle and leaves this with approxi ately supersonic, respective¬ ly with supersonic, speed as compared to the surrounding atmosphere around the locality to be cleaned. Though, it is to be noticed, that conditions may be thought of where the problems which are to be solved by means of the inven¬ tion are met at water jets or at jets of other media where the particles of the jet assume much smaller speeds. As already hinted at, that it according to the inven- tion may be advantageous, in particular in case of non- succeeded cleaning, to bring cleaning operation to halt which according to the procedure may be provided in that the memory means is provided with means which at non—de¬ tecting of emissions of water/ clogging material from the respective hole, respectively of ' non-terminated cleaning of a hole area, at the elapse of a certain time of opera— tion is able to release a signal to the running of the following procedure-step, respectively running of a halt- providing operational routine. A further development according to the invention con- nected with the procedure can be that the mentioned elapse of time of operation in case of water as cleaning means is 10 through 30 times the expected operational cleaning time per hole, and/or the memory means comprises means to up— count and/or to determine the frequency of appearing non- fulfilled cleanings of holes and for provision of alarm of error conditions and for possible issuing of signals for the providing of a halt of the cleaning operation. As also described previously above it may according to the invention at the procedure be advantageous that the die or other device with holes or passages to be cleaned is subject to be arranged in two or more different appara¬ tuses provided for the different kinds of hole or passage cleaning means, and of which at least one is a water jet cleaning means. The invention furthermore relates to an apparatus for the carrying out of the procedure. Such at least one appa¬ ratus can be characterized in that such at least one ap¬ paratus in more than one plane comprises stepmoving- eans, herea ong possibly 1ift-aπd-turn-step-moving-meanε, for the mutual displacing between cleaning means and die or other device with holes or passages to be cleaned, whereby the accuracy of the length of the steps is better than, i.e. in step lengths shorter than, or equal to the half of the smallest diameter of the holes or the passages to be cleaned. It is to be noticed, that the described procedure al¬ so takes into consideration that, although at the manufac¬ turing of the pelletizing dies accurately operating dril¬ ling devices are used, then in case of thin through-holes or passages the drills may have been bending sidewards du¬ ring the drilling operation due to the elasticity of the B drills. Of this reason some of the through-holes may hap¬ pen to be somewhat oblique oriented. But, during the clea¬ ning no damages of the holes takes place including those of even rather oblique orientation. On the other hand, the described device for positioning of the cleaning means is able to function effectively despite of the through—holes being unprecise located as due to such unprecise orienta¬ tion of the drills. It is further noticed, that the positioning of the cleaning means above a first die opening to be cleaned has to take place manually, whereupon the actual cleaning means is put into operation and sequentially the cleaning operations of the single through—holes or openings in the die is automatically brought to be carried out. It is also to be noticed, that the procedure accot— ding to the invention also is applicable for holes or ope¬ nings which do not present a tube shaped or conical shaped passage through the die, but may be composed of more cy¬ lindric shaped portions of different light, i.e. such as stepwise tapering light or a mixture of any such light and conically tapering lights. In dies as the mentioned pelletizing dies for feed stuff material pellets some 10,000 through 15,000 holes are comprised in each die. Aςcording to the invention some .1 through 10 seconds of time is required for the cleaning of the single holes or openings by means of the procedure. It is further to be noticed, that the aforementioned detecting means enabling a detecting of achieved cleaning of the single holes comprises mechanical, and in particu- lar movable, means or members against which material and cleaning medium from the cleaned holes abuts. By giving these a suitable suspension and shape, such as to describe as follows, a certain throw-back of cleaning medium, such as water, against the rear end of the cleaned openings may be attained advantageously providing a simultaneous clea¬ ning of the rear ends of the die holes DΓ openings. Embodiments according to the invention are described in more details in the following under reference to the drawing, wherein: FIG 1 in the perspective and schemati ally and having a portion of the protective housing cut away illustrates an embodiment of, for instance, a water jet apparatus according to the invention, FIG 2 is a view from the front along section II—II of the apparatus according to FIG 1 showing more details of a detecting means 3 which as an al¬ ternative is supported by a lance 2AA of a nozzle means 2A, and whereby a portion of a die to be cleaned is cut away for better viewing of the detecting means 3, FIG 3 illustrates the same members as according to FIG 2, but showing a section more CIDΞS to the centre of the die 1 and illustrating a varia¬ tion of the apparatus according to FIG 1 and FIG 2 suited for cleaning of holes in a die 1 and incorporating a cleaning to take place in opposite direction, FIG 4 in more details shows an embodiment of a detec¬ ting means 3 of the kind shown in FIG 1, FIG 2 and FIG 3, and FIG 5 in the perspective and having the two main mem¬ bers of the FIG mutually shown exploded and strongly schematized illustrates a through drill-cleaning operating apparatus according to the invention. In the FIGs of the drawing elements providing the sa¬ me or a corresponding function carry the same main sign of reference. A water jet apparatus according to FIG 1 of the draw¬ ing is intended employed for cleaning of clogged radially oriented through—passages, —openings or —holes in a massi¬ ve cylindric pelletizing die 1 of tempered steel material which is illustrated laying on a for instance horizontally oriented turntable 5A to which the die is for instance fastened rigidly with fastening means which are not shown but may be of per se known kind able to perform a rigid fastening of the die to the table, on one hand to maintain the position of the die on the table 5A on the other hand because a large pressure is exerted through the waterjet arriving at the die from a nozzle 2A on a lance 2AA. The turntable 5A is sitting on a rotary shaft 5B car¬ ried by bearings which are not shown. In principle the table 5A may be arranged displaceable upwards and down¬ wards at its bearings by resting on the periphery of an excentric disc 5HT being shown in dotted line and being located on a to the first mentioned shaft 5B perpendicular arranged and in dotted line shown rotary and through not illustrated bearings suspended shaft 5IT able to be turned by means of a εtep otor 5IDT shown in dotted line. The stepmotor comprises not shown gear means. On the other hand, this device to provide an upwards and downwards displacing of the table 5A is not well suited because the die 1 including the table 5A incorporates a considerable weight, such as 40 through 700 kg. It is thus more advan¬ tageous to provide the nozzle 2A as being displaceable up¬ wards and downwards by arranging the lance 2B displaceable upwards and downwards. As through the waterjet from the nozzle 2A large forces exist between the nozzle 2A and the die 1 demands are posed to rather rigid guiding means to provide a mechanical holding of the nozzle 2A in rela¬ tion to the die 1 which lays on the table 5A. To enable a turning of the table 5A carrying the die 1 the first mentioned shaft 5B carries a wor wheel 5C rotated by a worm 5D located on a driving shaft 5D driven, such as through a not illustrated gear means, by means of for instance a stepmotor 5ED. To provide a displacing up and • down of the nozzle 2A, the lance 2B is rigidly fastened by means of clamps 2C to a such as in U- or C-shape formed plate means 2D being ar— ranged displaceable up and down on an as rail serving hol¬ ding means 2E which through further suitable fastening means is located on a supporting means, which here carries reference numeral 6, and by means of which also the table 5A and the driving means belonging to the table are kept properly fastened. Here, the supporting means is shown as a rigid box- shaped means 6 supported on four legs comprising a cavity, the front of which is to be closed by means of a not illu¬ strated door or cover plate which on the one hand serves to catch water emanating from the nozzle 2A and clogging matter being released from the cleaned holes or openings, and which door or cover plate on the other hand protects the surroundings against water or any other as fluent or rayed, such as in powder shape rayed, matter which with great power is ejected from the nozzle 2A. To provide a displacing up and down of the nozzle 2A, for instance a threaded shaft 51 is provided which at one end undisplaceably is kept in place by a bearing 5H at the plate means 2D and at the other end is kept rotary in place by means of an internally threaded bearing means, such as the hub of a tooth wheel driven by a drive motor 5ID which thus may be a stepmotor device incorporating a not further illustrated gear means being inserted between the motor and the said toothwheel. At the embodiment shown in FIG 1 the nozzle 2A through the lance 2B is thought connected to a not illu- strated pressurized water producing compressor device. The said stepmotors may be εtepmotorε of the electric kind which through indicated connecting wires are connec¬ ted to a not shown control unit issuing the necessary control εignalε able to control and drive the εtepmotors. This electric control unit also comprises a possible memo- ry device or other control means which is connected to a signalling or detecting means 3 to be described with refe¬ rence to FIG 4 and indicated in FIG 1 and through which the stepwise movings of the die 1 and the nozzle 2A are provided. Of FIG 2 which on the other hand illustrates a some¬ what different manner of fastening the detecting means 3 it is to be understood that at the piercing through the die 1 a by dotted line indicated waterjet from the nozzle 2A together with ejected clogging matter from the hole or opening in the die 1 is going to hit for instance a slab member 3A being suεpended pivotable around a horizontal axis and which slab member 3A through its moving is activating an electric switch or signal means for as long a duration of time as the waterjet is passing through at this detecting eanε 3. The stepsize of the mutual moving between the nozzle 2A and the die 1 has to be so adapted that a mutual moving is permitted with an accuracy which is better than equal to the half of the ε allest diameter of the holes or ope- niπgε in concern, i.e. aε measured from the middle of a cleaned hole or opening to the next hole or opening to be cleaned and which hole or opening generally, for a given direction of moving, simul aneously is the nearest hole or opening. Experiments have thus shown that a positioning of the holes or openingsof a die in front of the nozzle with this accuracy then at the further implementing of the cleaning procedure it is to be regarded as advantageous when the die by meanε of its suspension and the nozzle by meanε of its suspension, thus inclusive posεible drive meanε devices enabling the stepwise moving, mutually caused by these suspension and drive device means are kept in position elastically, elaεtomeric or to a suitable degree by spring meanε with an accuracy which permitε a mutual εelf— oving of these members with a size of thiε self-moving to be within the size of the half of the diameter of the smallest hole or opening to be cleaned in the die. In this manner the waterjet from the nozzle 2A is imparted the possibility through its unavoidable mutual influence of moving, existing between the die and the nozzle, itself to provide a centering of the waterjet within the single holes or openings to be cleaned. In FIG 2 and FIG 3 embodiments of nozzle devices 2A and cooperating detecting means 3 are illustrated as al- ready mentioned. Of FIG 2 it is understood that the detecting meanε 3 comprises a pivotable slab meanε 3A which through itε up- wardε moving due to influence from the in dotted line in¬ dicated and through a hole or an opening in the die arri- ving waterjet from the nozzle 2A activates a signal meanε 3C. The detecting meanε 3 is kept in place by meanε of a suitable strong holding means 3S at the lance 2B. Experi¬ ments have shown that the detecting means 3 is kept well in place by means of for instance a phosphor bronze ribbon having a width of 10 through 30 mm and a thickness of 2 through 5 mm. According tD FIG 3 the nozzle according to FIG 2 by means of for instance a suitable coupling procedure is substituted with a rigid tube joining meanε 2AX bringing the lance 2B to extend to the nozzle 2A which in thiε case is arranged turned against the internal wall of the die 1. To achieve a waterjet being as εmooth aε possible, i.e. apparently as not being ejected as a whirling waterjet, a longer length of the lance 2B is running shaped as a straight length behind the nozzle 2A. To safeguard a sui¬ tably fastened keeping in place of the nozzle 2A a connec¬ ting strut member 2BB is arranged for the lance 2B. In this case the waterjet from the nozzle 2A is going to pass through the die 1 in opposite direction as compared to the direction at the embodiments according to FIG 1 and FIG 2. In case of dies fitted with very long and narrow holes or openingε, i.e. εuch aε having lengthε greater than 15 cm and diameterε of the holes or openingε εmaller than 5 mm, it may be necessary to do a cleaning in both directions through the holes or openingε to achieve that all clogging matter or rests thereof is removed from the holeε or ope¬ nings, because an avoidable returning jet from the water— jet at the pasεage through the narrow holes or openings makes it difficult to achieve a full—cleaning of the εing- le holeε or openings in their entire lengths. A possible embodiment of the detecting means 3 is more clearly illustrated in FIG 4. Though, the suspenεion 3S is only indicated. On the other hand, it is shown that the pivotable slab meanε 3A is somewhat S-shaped. This shape haε εhown itself advantageous in relation to the wa¬ terjet which is indicated by means of an arrow V. Through this embodiment two advantages are attained, namely first¬ ly in that it is counteracted that the waterjet influences mechanically strongly eroding on the materialε which the jet hits, and thuε the indicated shape iε advantageouε in that a low degree of eroεion iε achieved, and εecondly in that water which hits this pivotable slab means is brought to sprinkle in different directions. The sprinkling which is achieved has shown itεelf to be effective in εuitably rincing the surface of the dies which have become dirty by being covered with feed pellet material when the dieε were used for pelletizing, and thuε the εurroundingε of the ho¬ les or openings are cleaned for adherent pellet material. This effect is in particular advantageous when the detec- ting means 3 with the pivotable slab meanε iε located at the open inner range of the die. In FIG 1 it is furthermore illustrated that material being caught by the housing 6 within the housing iε led to an outlet tube 7A and in shape of a ray 7B to a water cleaning filtre 7D and through .a collecting channel 7C. The water cleaning filtre 7D catcheε εolid particleε and is able collecting to be turned forward by being pulled by driving rolls at 7E arranged at a box 7S belonging to the water cleaning filtre. Water, having passed through the apparatus and the die, from the very hot condition existing for the arriving mixture of water and clogging matter is for instance led to a cooling device, such as of cooling tower type, and from there to a water supply able to deliver water for a renewed passage through a compres- εor device providing, by passing the water through the nozzle 2A, a waterjet exhibiting very high water pressure. The provided waterjet then only has a thickness of appro¬ ximately the size of the half of the smallest hole or ope¬ ning to be cleaned by means of the apparatus. To achieve a cleaning of the external ranges of the holes or openings when performing the cleaning it often may be advantageouε, at leaεt at one end of the holeε or openingε, to perform an afterdrilling of theεe external ranges by employing fDΓ instance a counter—sinking-provi— ding apparatuε aε described earlier. The eεsential members belonging to such an apparatus are shown in FIG 2. A drill 4A is bearing supported by a holding means 4B and is driven by means of a drilling dri¬ ve meanε 4CD through a shaft 4C and through a not illu— strated gear means which for instance may be located in the holding means 4B. The holding means permits through an up and down displaceable means 4D a corresponding up and down moving of the drill 4A controlled by a plate shaped e center means 4E located on a shaft 4F driven by a step- motor 4FD. This is carried by a supporting means 4G which together with the holding meanε 4B and the drill drive mo¬ tor 4CD iε located on an on railε to and fro movable εup— porting means which through suitable sliding bearing means 4SA rests on rails SL. An in relation to the rails SL stationary stepmotor 4ID is through a not illustrated gear means through a for inεtance indicated threaded shaft 41 and through a with internal thread fitted hub provided toothwheel as bearing 4H able to drive the supporting means to and fro on the rails SL. The complete portion of the apparatus carries reference numeral 4 and can as shown in the left hand portion of FIG 2 be located in poεition within a die 1. The die 1 reεtε between two εupporting plate meanε located on two, here as horizontally oriented, εhown εhafts ISA and 1SB, of which one of them ISA through a shaft extenεion ISC iε able to be rotated by meane of a stepmotor 1SD through for instance a gear means which is not illustrated. At the portion of the apparatus illustrated in FIG 2 the stepmotorε 1SD and 4ID correεpond to the εtepmotors 5ED and 5ID according to FIG 1 in what relates to the providing of a mutual moving between the working memberε, namely respectively 4A and 2A, and the holeε or openingε to be cleaned in the die 1. The mutual moving may in both caεeε be controlled in the same manner in that the detecting means 3, which was deεcribed under reference to embodiments according to FIG I, when employing a working member 4A iε thought substituted by a correεponding one which for inεtance is mounted so that it iε connected with the up-down-movable means 4D or with the excentric plate means 4E, and whereby the detecting meanε indicateε εatiε— factory done drill—cleaning—operationε when cleaning the single holes or openings of a die 1. When . employing such kind of detecting, step-moving mtutally between the wor¬ king means 4A and the die 1 to achieve poitioning, iε pro— vided in the same manner aε earlier deεcribed, euch aε to attain the required poεitioning for carrying out of a cleaning of the next hole or opening of the die. Without specifically describing details a counter may be used for counting the amount , of cleaned holeε or ope— nings whereby the counting iε carried out in one direction or the other for instance around along or acrosε the em¬ bodied ring shape of a die, i.e. a successive counting of cleaned holes or openings is carried out unto a wanted amount of holeε or openings is reached, whereafter the cleaning is brought to continue with another successive row of holes or openings along or acroεs the ring εhape of the die, etc. Such counter devices are known and belong to the state of the art and need no further description. It haε to be noticed, that experience εhowε that only comparatively few cases are found, where ejected matter from a hole or from an opening hits the opposite wall in the die so that a part of this matter is able to penetrate into a hole or an opening and remains sticking there. Thus, experience shows that a blowing of the die with pressurised air after the carrying out of the deεcribed cleaning according to the invention, in practice removes all remaining rests of matter from the holes or openings including such matter which during the cleaning was brought to stick in the holes or openings again.

Claims: C L A I M S 1. A procedure for cleaning of clogged holes or passa¬ ges of lesser diameter, such as through-holes or through- holes with light of varying sizes, in particular such ho- les in dies provided with a large amount of such holes for through-presεing of materialε at the manufacturing of pellets, εuch aε dies employed at pelletizing of feed stuff pellets, c h a r a c t e r i z e d in the fol¬ lowing procedure steps, whereby objects with clogged holes to be cleaned are specified as dies, and in that the die is located on a suitable εupportiπg meanε comprising holding means for the fastening of the die in relation to a water jet means, whereby these said holding means com¬ prises activatable position adjusting means for adjusting or readjusting the εaid faεtened mutually fixedly holding which fastening to a lesser degree, possibly by means of a minor flexibility and/or spring induced flexibility, only is to be characterizable as a limited fastening, and in that with an accuracy being of the εize being within the half of the smallest hole diameter or better a water jet with a diameter being of the size less than the half of the smallest hole diameter is directed against the firet hole to be cleaned having the direction of the longitudi¬ nal orientation of the hole, and in that the degree of mutual fixation between the mentioned elements iε main¬ tained to εuch a degree so that approximately the flexibi¬ lity of the fixation permitε relatively a mutual moving between these said elements to be less than the said half hole diameter of the ε allest hole in the die to be cleaned, and in that a behind the hole arranged detecting meanε detecε the arrival of water reεpectively of clogged material from the rear end of the hole and activateε memo¬ ry meanε reεulting in either stqp of cleaning operation or in mutual displacing taking place through activation of the said poεition adjusting or readjuεtiπg means for the die/water jet with a mutual displacing corresponding to the mutual spacing between the centre of the cleaned hole and the centre of the next hole to be cleaned with an accuracy of the displacing being better than the half of the smallest hole diameter and with the water jet being directed towards this opening oriented in the longitudinal direction of the hole, and whereby the procedure continueε aε deεcribed above at "and in that the degree of mutual fixation between the mentioned elements is ". 2. Procedure according to claim 1 c h a r a c t e ¬ r i z e d in that procedure steps are applied to the procedure by which the water jet is substituted with a drilling or cleaning means which solely is able to perform cleaning of the area at one end of the holes, and whereby the detecting means is provided able to detect termining cleaning of the single areas of these ends of the holes. 3. Procedure according to claim l o 2 c h a r a c ¬ t e r i z e d in that the cleaning water jet may be pro- vided able to clean in a usual direction aε well aε in the opposite direction through the holeε. 4. Procedure according to claim 1, 2 or 3 c h a ¬ r a c t e r i z e d in that the cleaning water jet under an extremely high preεsure is emitted from a nozzle and leaves this with approxi ately supersonic, reεpectively with superεonic, εpeed as compared to the surrounding at¬ mosphere around the locality to be cleaned. 5. Procedure according to claim 1, 2, 3 or 4 c h a ¬ r a c t e r i z e d in that the memory means is provided with meanε which at non-detecting of emisεioπε of water/ clogging material from the respective hole, respectively of a non—terminated cleaning of a hole area, at the elapse of a certain time of operation is able to release a signal to the running of the following procedure—step, respecti— vely running of a halt-providing operational routine. 6. Procedure according to claim 5 c h a r a c t e ¬ r i z e d in that the mentioned elapse of time of operation in case of water aε cleaning means is 10 through 30 times the expected operational cleaning time per hole, and/or the memory means comprises means to up—count and/or to determine the frequency of appearing non-ful illed cleanings of holeε and for proviεion of the alarm of error conditione and for possible issuing of signals for the providing of a halt of the cleaning operation. 7. Procedure according to claim 2, 3, 4, 5 or 6 c h a r a c t e r i z e d in that the die or other device with holes or passages to be cleaned is subject to be arranged in two or more different apparatuses provided for the different kinds of hole or passage cleaning means, and of which at least one is a water jet cleaning means. S. At least one apparatus for the carrying out of the procedure according to claim 1, 2, 3, 4, 5, 6 or 7 c h a r a c t e r i z e d in that such at leaεt one ap— paratuε in more than one plane comprises stepmoving-means, hereamong possibly li t-and-turn-step-moving-means, for the mutual displacing between cleaning means and die or other device with holeε or paεsageε to be cleaned, whereby the accuracy of the length of the steps is better than, i.e. in step lengths shorter than, or equal to the half of the smallest diameter of the holes or the passages to be cleaned. 9. Apparatuε according to claim 8 c h a r a c t e ¬ r i z e d in that the aforementioned detecting meanε enabling a detecting of achieved cleaning of the single holeε comprises mechanical, and in particular movable, means or members againεt which material and cleaning me¬ dium from the cleaned holeε abuts. 10. Apparatuε according to claim 9 c h a r a c t e ¬ r i z e d in that the detecting meanε (3) by way of example in longitudinal εection iε a S-shaped pivotable slab means (3A> being pivotably supported by a suitable strong, i.e. rigid, carrying suspension C3S> .

Inventors: PEDERSEN BENNY, SIHM KURT, PEDERSEN, BENNY, SIHM, KURT
Applicants: O & J HOJTRYK AS, O & J HOEJTRYK A/S
Application year: 1990
Main classification: B08B3
IPC codes: B08B3, B29C47, B30B11