Method for test-pressing pellets in rotary press

Abstract

To provide a reliable and low-effort method for achieving test pressing for setting a rotary press for production operation.SOLUTION: A method for test-pressing pellets in a rotary press comprises: moving a punch pair to a filling position; filling a material to be compressed into receptacles; moving pressing units of a pressing apparatus toward one another such that an expected web height of a pellet to be manufactured in the test pressing is reached; putting a rotor into rotary motion, so that the punch pair comes into contact with the pressing units for compressing into a pellet the material filled into the receptacle, where the pressing force and / or a parameter characterizing the pressing force is determined; and, upon reaching a preset pressing force and / or a preset value of the parameter characterizing the pressing force, arresting the rotor and rotating the rotor in the opposite direction, so that the punch pair comes out of contact with the pressing units.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a method for pressing and testing pellets in a rotary press, comprising a rotationally driven rotor with upper and lower press punches, upper and lower punch guides for the upper and lower press punches, and a die plate between the punch guides, wherein the upper and lower press punches interact with receptacles in the die plate during a production run of the rotary press, further comprising a filling device for filling the receptacles with material to be compressed during the production run, and further comprising a pressing device having an upper press unit and a lower press unit, wherein the upper press unit and the lower press unit interact with the upper and lower press punches during the production run, and wherein the press units compress the material in the receptacles to form pellets. [Background technology]

[0002] Press tests are carried out, for example, to determine the optimal configuration parameters of a rotary press for a new compressed material or to produce pellets during a production run. In particular, the pellets can be tablets. In order to press tablets with the smallest possible product load within the scope of the press test, so-called single-punch tablet presses are used, which are presses with only one pair of upper and lower punches. These are specially designed for press tests that do not normally have a rotor and are not suitable or envisaged for normal production runs, in particular for pellet production. In such press tests, all data within the scope of the press test, which relate to the way in which the material is produced into tablets during a production run, are determined for a specific product, i.e. a specific compressed material. The data obtained are then transferred to the respective rotary press for the production run, where they must be adjusted in order to obtain the desired properties of the tablets produced. The advantage of a single-punch press test is that a very small product load is required for the pellet or pellets produced within the scope of the press test. However, the disadvantage of this method is that a press test must be provided in addition to the rotary press for carrying out the production run. Furthermore, the data obtained cannot be directly transferred to the rotary press for the production run, in particular due to the different components of the press. The data obtained must therefore be adjusted to the production press, which usually requires additional press tests to be performed for the rotary press in production operation.

[0003] German patent specification 10319024 discloses a method for press testing of tablets in a rotary tablet making machine, which is carried out on a rotary press for normal production operation. In this method, the punch pair selected for a single compression is automatically moved to the filling position, the filling device is at least partially moved, and the die or a limited number of dies are filled with material while the rotor is stopped. The rotor then rotates and is accelerated to reach a predefined production speed in the pressing position. After one revolution, the rotor stops again in the filling position. During the rotation of the rotor, the signals of the measuring points and / or the signal paths are recorded and entered into a computer for display and evaluation. The advantage of this method is that no separate press test is required for the press test. This reduces the effort. At the same time, the data obtained within the scope of the press test can be used directly since it is already obtained on the rotary press for production operation and requires little adjustment. This also reduces the effort. Furthermore, since only one or a few dies are filled with material, the product consumption required for the press test can be kept low at the same time. However, in the first press test, the web height of the resulting tablets must be estimated based on the fill in the die. At the press position, an unknown press force is initially generated. The press force suitable for each product must be determined within the limits of multiple press tests. As a result, the effort and product usage increase again. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] German Patent Specification No. 10319024 Summary of the Invention [Problem to be solved by the invention]

[0005] Departing from the prior art mentioned above, the present invention aims to achieve the object of providing a method as mentioned at the beginning, in which a press test for setting up a rotary press for production operation can be performed reliably and with low effort. [Means for solving the problem]

[0006] The invention achieves this object with the aid of the independent claim 1. Advantageous embodiments are set out in the dependent claims, the description and the drawings.

[0007] With regard to a method of the type mentioned at the beginning, the invention relates to a punch pair of an upper press punch and a lower press punch assigned to a receptacle of the die plate is moved to a filling position such that the upper press punch moves upward from the receptacle and the lower press punch is partially located in the receptacle, the lower press punch presetting a maximum filling height of the material to be compressed in the receptacle; - filling a receptacle with the material to be compressed; - moving the press units of the press relative to one another such that the predicted web height of the pellets produced in the press test is reached before the pair of punches exceeds a position of a minimum distance between the press units during rotation of the rotor; determining a pressing force and / or a parameter characteristic of the pressing force, so that the rotor enters a rotational motion and the punch pair comes into contact with the pressing unit to compress the material filled in the receptacle into a pellet; when the preset pressing force and / or the preset value of the parameter characteristic of the pressing force is reached, the rotor stops and rotates in the opposite direction so that the punch pair is taken out of contact with the press unit; By doing so, the objective is achieved.

[0008] The rotary press used with the method according to the invention is a rotary press provided for the usual production of pellets, in particular tablets, from materials, in particular powder materials. In the known method, the rotary press comprises a rotor with a number of upper and lower press punches, each of which is assigned in pairs to receptacles and / or cavities of the die plate. The receptacles can be implemented as straight bores in the die plate. They can also be designed as sleeve-like inserts that are inserted into assigned larger receptacles of the die plate. During operation of the rotary press, the upper and lower press punches rotate together with the die plate, the axial movement of which is controlled by a control cam and guided by an upper and lower punch guide. The control cam usually interacts with the punch head of the press punch. During the rotation of the production run, the die plate passes through various devices of the rotary press, namely the filling device and the pressing device, in which the powder material to be compressed is filled into the receptacle of the die plate, and in which the upper and lower pressing punches are pressed into the receptacle by upper and lower pressing units, for example upper and lower pressing rollers or pressing wedges, and the powder material is compressed into pellets, such as tablets. The pressing device can comprise, for example, a pre-pressing roller and an upper and lower main pressing unit, for example a main pressing roller. Downstream of the pressing device, the upper pressing punch is guided upwards from the receptacle, and the pellets generated in the receptacle are pushed by the lower punch to the upper side of the die plate. For this purpose, an ejection cam is provided, which moves the lower pressing punch upwards. By means of a scraper, the pellets are scraped off from the die plate to the output of the rotary press, from where they are fed for further processing. The control cams also typically comprise a fill cam which, when the upper press punch is guided upwardly from the respective receptacle, moves the lower press punch to a preset position where it is partially guided into the receptacle, in which the lower press punch constitutes the bottom of the respective receptacle and thus defines the maximum fill height of the material to be filled into the receptacle.

[0009] As mentioned above, the rotary press used in the method according to the invention is a rotary press for normal production operation. As will be explained in more detail below, the rotary press can be adjusted in order to carry out a press test. In particular, components of the rotary press, such as for example the upper and lower press punches and / or the filling device, can be removed before the start of the press test. In the method according to the invention, the punch pairs of the upper and lower press punches assigned to the receptacles of the die plate are moved to a filling position, in which the upper press punch is moved out of the receptacle as mentioned above and the lower press punch is partially located in the receptacle, so that a maximum filling height of the material to be compressed in the receptacle is preset. In the filling position of the punch pairs, the rotor can be stopped. The material to be compressed, in particular the powder material, as mentioned above, is then filled into the receptacle. In a particularly practical form, the punch pairs can be moved into the filling position by the assigned rotation of the rotor. However, it is also possible for the punch pairs to be purposefully attached to the rotor in the filling position.

[0010] In the method according to the invention, the upper and lower press units of the press device move further towards each other in the range in which the web height of the pellets, in particular tablets, produced in the press test is expected before the punch pair exceeds, in particular reaches, the position of the minimum distance between the press units during the rotation of the rotor. In this case, the web height corresponds to the height of the outer surface of the pellets, i.e. the part of the pellet, in particular the cylindrical part. This is also called the cylindrical height. The web height is the part of the pellet that is not affected by the shape of the punch tip of the press punch, in particular the one with which the pellet is compressed. Thus, the oppositely arranged press punches approach each other in the course of the pressing process until they reach a minimum distance corresponding to the web height. Convex deviations in the shape of the upper or lower outer surface of the pellets, etc., are not taken into account. The web height of the produced pellets is therefore determined from the minimum distance that occurs between the upper and lower punches during the pressing process. Thus, given the axial punch length, the web height is defined by the distance between the press units.

[0011] As mentioned above, the upper press unit is an upper press roller or an upper press wedge, and the lower press unit is a lower press roller or a lower press wedge.

[0012] During rotation of the rotor, the punch pair comes into contact with the press unit of the press device. As determined by the geometry of the press unit, the distance between the press units decreases along the direction of rotation of the rotor and / or along the direction of rotation of the press punch pair. For example, in the case of a press roller, the punch pair advances against the rising range of the press roller during the rotation of the rotor. The distance between the press units decreases as the rotor rotates further, until the punch pair reaches the minimum distance between the press units. For example, in the case of a press roller, this is achieved when each punch of the punch pair aligns its longitudinal axis on an imaginary line connecting the rotation axes of the opposing press rollers. As the rotor rotates further, the distance between the press units increases again and the respective punches of the punch pair move away from each other. The press units are guided together such that the predicted web height of the pellets compressed in the press test is reached before the punch pair exceeds the position of the minimum distance between the press units during rotation of the rotor; By adjusting the press units so that pellets of the predicted web height are produced in the press test before the minimum distance between the press units is reached, it is ensured that the pressing process is completed up to the predetermined maximum pressing force in the area where the distance between the press units decreases along the ascending arrangement of the press units, e.g. along the ascending range of the press rollers. In the press test, the rotor of the rotary press enters into a rotational movement and the punch pair for compressing the material guided into the receptacle comes into contact with the press unit. During the pressing process, which is carried out by the contact of the upper and lower press punches with the upper and lower press units, a parameter indicative of the pressing force and / or the characteristics of the pressing force is determined. In the press test, as described above, the punch pair is moved into contact with the press unit by the rotational movement of the rotor and is further guided against the upward arrangement of the press unit. With the continued rotation of the rotor, the upper and lower press punches approach each other vertically according to the arrangement of the press units in normal production compression. In this way, the material in the receptacle is compressed into pellets. When it is determined that the preset pressing force and / or the parameter indicative of the characteristics of the pressing force based on the detected values ​​has reached a predetermined value, the rotation of the rotor is stopped, the rotor rotates again in the reverse direction and the punch pair leaves the press unit again. At this time, the generated pellets can be manually removed from the receptacle. In this case, the axial movement of the upper and lower press punches together with the upper and lower punch guides is guided by a control cam of the rotary press. In this case, the rotor can be rotated back to the loading position of the punch pair. However, the rotor can also be moved to another rotational position, for example to a position where it is easier to remove the produced pellets, for example to an ejection position where the lower press punch brings the pellets to the upper side of the die plate.

[0013] The method according to the invention allows individual tablets to be press tested in a normal production rotary press, while minimizing the product usage of the material to be compressed. The data generated within the scope of the press test is therefore directly available in the system of the production rotary press. Neither the transfer of data from another press test nor its adaptation to the production rotary press is necessary. The omission of the press test reduces the installation effort. The press test itself also requires only minor installation effort. In the present invention, in so far as the press units of the press device are guided to one another to such an extent that the desired pressing force for the respective material is exceeded during one complete pass through the press device, it is reliably ensured during the press test that the pre-set pressing force is achieved and not exceeded based on the determination of the pressing force or a parameter characteristic of the pressing force. Once the desired pressing force is reached, the pressing process is terminated by stopping the rotation of the rotor and the press punch pair is guided in the opposite direction, in particular so as to be pulled out of contact with the press unit. The pressing process is completely carried out before the press punch pair exceeds the minimum distance between the press units. This allows the first pellets of the press test to be compressed already with the desired pressing force without knowledge of the compression properties of the respective compressed material, i.e. whatever the web height the pellets reach, which can be determined before the press test and can be achieved exactly with the method according to the invention.

[0014] The method according to the invention can be carried out, in particular automatically, by a control device of the rotary press, except for the manual filling of the receptacle with the material. The control device is configured as a machine control device for controlling the production run of the rotary press or is respectively integrated. Based on the results of the press test, the rotary press can set all components for the subsequent production run. This can also be done via the control device. This concerns, for example, the desired setting of the filling cam and / or the pressing device, in particular the pressing unit such as the pressing roller or the pressing wedge and / or the rotation speed of the rotor. The pressing force or a parameter characteristic of the pressing force can be measured by means of an assigned sensor. For this purpose, the rotary press is equipped with an assigned sensor, for example a pressing force sensor on the pressing device or a pressing force sensor attached to the pressing unit. The parameter characteristic of the pressing force and / or the determined additional parameter can also be measured, if necessary, by means of an assigned sensor of the rotary press.

[0015] The steps of the method according to the invention do not have to be carried out in the order recited in claim 1. In particular, the press units can be moved relative to one another before or when the punch pair is moved to the filling position or before or when the material to be compressed is filled into the receptacle.

[0016] According to an embodiment, the parameters characteristic of the pressing force are the rotor rotation position, the web height, the pressing force curve and / or the pressing dwell time at a preset pressing force. The rotor rotation position is typically determined by the rotor angular position. The web height can be determined, for example, by the axial path of the upper and lower press punches. The pressing dwell time indicates the time during which the pellets are compressed to a minimum volume. During the pressing dwell time, the path of the press punches does not change in any way. The pressing force curve can be determined by time or, for example, by the rotor revolutions.

[0017] The pressing force and / or parameters characteristic of the pressing force are taken into account for setting up the rotary press for production operation, as described above.

[0018] According to another embodiment, additional parameters are determined during and / or after the press test, comprising the pressing force curve, the punch path curve of the upper and / or lower press punch, the maximum pressing force, the pressing dwell time at a given pressing force and / or the web height of the produced pellets. Again, as mentioned above, suitable sensors can be provided to measure these additional parameters. Additional parameters can also be determined after the press test, such as for example a measurement of the actual web height of the produced pellets.

[0019] The additional parameters are also taken into account when setting up the rotary press for production runs. As mentioned above, the values ​​or the respective parameters determined according to the invention can already be used in the rotary press for production runs and can be used directly to characterize the material to be compressed or, respectively, to set up the rotary press for production runs depending on the material to be compressed.

[0020] According to another embodiment, during the press test, it is possible to mount only the punch pairs assigned to the receptacles of the die plate on the rotor. The remaining punch pairs on the rotor can be removed. Of course, it is also possible to leave some punch pairs on the rotor and remove others or to leave all punch pairs on the rotor. The advantage of locating only the punch pairs used for the press test is that there is no interaction between the punch pairs and other rotary press parts, for example when the receptacles assigned to them are not filled with material.

[0021] According to another embodiment, the filling device of the rotary press can be removed or stopped during the press test. The advantage of this is that receptacles not used during the press test are not filled with compressed material when this is not desired. For example, it is possible to completely or partially remove the filling device from the rotor. It is also possible to empty the filling device or to seal the filling port through which the material is filled from the filling device into the receptacle. In this way, it is possible to avoid complex measures to prevent the receptacle from being filled, such as, for example, the insertion of a blind die plate.

[0022] According to a particularly practical embodiment, the material to be compressed in the press test can be filled into the receptacle manually, however, it is also conceivable to fill the receptacle with the material via the filling device or another filling equipment.

[0023] According to another embodiment, in the press test, the rotor can be driven in rotation at least one third faster than in the production run of the rotary press. It is also possible to drive the rotor in rotation up to the maximum production speed in the production run. Using a rotation speed according to the above embodiment creates particularly representative test conditions for the subsequent production run. Typical production speeds of the rotor of a rotary press are, for example, in the range of 5 revolutions / min to 120 revolutions / min.

[0024] According to another embodiment, multiple press tests are performed, varying the rotation speed of the rotor and thereby varying the pressure force progression and / or the punch path progression. For example, sinusoidal and / or sawtooth and / or square wave pressure force progressions and / or punch path progressions are set over time or rotor revolutions. By means of a variable drive of the rotor rotation, different pressure force and / or punch path curves can be easily set. In this way, it becomes easier to find the optimum rotary press settings for the subsequent production run.

[0025] According to another embodiment, several press tests can be performed, using punch pairs with different punch heads and / or punch tip geometries. In a production run, the punch tip of the press punch sinks into a receptacle in the die plate and compresses the material into pellets. The punch tip is arranged at one end of the punch. The punch head, interacting with a control cam for controlling the axial movement of the press punch, is arranged at the opposite end. In this way, the rotary press can be pre-configured with different punch heads and punch tip geometries. The respective optimal operating parameters for a production run are stored in the rotary press control device and the user can select these by specifying the type of punch to be fitted respectively. It is also possible to simulate different punch geometries for configuring the rotary press by modelling the movement and / or speed curve of the press punch during the pressing process with the rotor rotation speed.

[0026] Embodiments of the invention are explained in detail below with reference to the figures, which are shown diagrammatically. [Brief description of the drawings]

[0027] [Figure 1] 1 is a schematic diagram of a rotary press used in the method according to the present invention, showing an exploded view of the rotor; [Diagram 2] FIG. 2 is an enlarged cross-sectional view of a portion of the rotary press shown in FIG. 1 for illustrating the method according to the invention;

[0028] In the figures, like reference numbers refer to the same items unless otherwise indicated. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0029] The rotary press shown in FIG. 1 is a rotary press for tablet production used in the present invention, which compresses powder material to produce pellets, in particular tablets. The rotor of the rotary press comprises a die plate 10, which is driven in rotation by a rotary drive and has a number of receptacles 12. The receptacles 12 are formed, for example, by holes in the die plate 10. The rotor further comprises a number of upper press punches 14 and a lower press punch 16, which rotate synchronously with the die plate 10. The upper press punch 14 is guided axially in an upper punch guide 18, and the lower press punch 16 in a lower punch guide 20. In the course of the rotation of the rotor, the axial movements of the upper press punch 14 and the lower press punch 16 are controlled by an upper control cam part 22 and a lower control cam part 24. Furthermore, a filling device 26 is provided, which comprises a filling storage chamber 28 and a filling chamber 30, which are connected via a filling pipe 32. Thus, in this embodiment, the powder material flows by gravity from the fill reservoir 28 through the fill tube 32 into the fill chamber 30, and from there through a fill opening provided on the underside of the fill chamber 30 into the receptacle 12 of the die plate 10.

[0030] The rotary press further comprises a press device 34. In the illustrated example, the press device 34 comprises a preliminary press device having an upper press roller 36 fixed to an upper holder 35 and a lower press roller 38 fixed to a lower holder 37, and a main press device having an upper press roller 40 fixed to an upper holder 39 and a lower press roller 42 fixed to a lower holder 41. The rotary press further comprises an extrusion device 44 and a scraping device 46 having a scraping part that supplies tablets 48 produced by the rotary press to a discharge device 50 for discharging the tablets from the rotary press. The scraping device 46 comprises, for example, a scraping part, preferably crescent-shaped, which scrapes off the tablets 48 conveyed to the upper side of the die plate 10 by the lower press punch 16 in the region of the extrusion device 44 from the die plate 10 and supplies them to the discharge device 50.

[0031] The rotary press further comprises a controller 52 for controlling the operation of the rotary press and for carrying out the method according to the present invention, as will be further described below.

[0032] Figure 2 shows a part of the rotary press shown in Figure 1 to explain the method according to the invention. Only the upper control cam part 22 and the lower control cam part 24 are shown in the figure, as well as only two punch pairs, the upper and lower press punches 14, 16, and only the upper press roller 36 and the lower press roller 38, which are pre-pressing devices in the press device 34. It is also possible, for example, to mount only one punch pair, the upper and lower press punches 14, 16, on the rotor to carry out the method. Figure 2 shows two punch pairs to explain the different steps of the method.

[0033] The punch pair of upper press punch 14 and lower press punch 16 shown on the left side of FIG. 2 is moved upwards from the receptacle 12 of the die plate 10 by the upper control cam part 22 shown in FIG. 2, in which the upper press punch 14 is located in the receptacle 12 in the filling position assigned to the punch pair. The lower press punch 16, controlled by the control cam part 24, in particular the filling cam part 24, is located partially in the receptacle 12, thereby defining the maximum filling height of the receptacle 12 of the material to be filled in the receptacle 12. In this filling position, the material is manually filled into the receptacle 12, for example when the rotor is stopped. The receptacle 12 is then completely filled up to its upper end. If necessary, excess material can be scraped off from the upper surface of the die plate 10.

[0034] The rotor is then moved in rotation, as is evident from the punch pair shown on the right side of FIG. 2, so that the punch pair moves to the right side of FIG. 2 with the rotation of the die plate 10 and comes into contact with the press rollers 36, 38. The press rollers 36, 38 have been moved towards each other to some extent in advance, so that the punch pair reaches the expected web height of the pellets produced in the press test before exceeding, and in particular reaching, the position of the minimum distance between the press rollers 36, 38 during the rotation of the rotor. The invention ensures that in the range of the press test, the upper and lower press punches 14, 16 never exceed, and in particular do not reach, the imaginary connection line 54 depicted in FIG. 2 between the rotation axes of the press rollers 36, 38.

[0035] This setting of the press rollers 36, 38 ensures that a preset maximum pressing force is reached in the pressing device 34, in particular in the upper and lower press rollers 36, 38, before the upper and lower press punches 14, 16 exceed the area of ​​the minimum distance between the press rollers 36, 38 in the course of their rotational movement. The pressing force and / or a parameter characteristic of the pressing force are measured during the contact of the press punches 14, 16 with the press rollers 36, 38, in particular by suitable sensors of the rotary press. When the preset value of the parameter characteristic of the pressing force and / or the pressing force is reached, the rotary movement of the rotor stops and then the rotor rotates in the opposite direction so that the punch pair does not come into contact with the upper and lower press rollers 36, 38 again. The produced pellets 48 can then be removed from the receptacles 12 of the die plate 10. The measured values ​​can be used to set the rotary press for a production run with material compressed within the range of the press test.

[0036] As is clear from the above description, in the present rotary press, the press test is performed with the press rollers 36, 38, which are the preliminary press devices of the press device 34. Naturally, the press test can also be performed in a similar manner with the press rollers 40, 42, which are the main press devices of the press device 34, and even in rotary presses that do not have a preliminary press device, or even if the press rollers 36, 38, which are the preliminary press devices, are sufficiently separated from each other so that the punch pair of the upper and lower press punches 14, 16 does not contact them at all or is not sufficient to achieve a preset pressing force or a parameter value that indicates a characteristic of the pressing force. [Explanation of symbols]

[0037] 10 Die Plate 12 Receptacle 14 Upper press punch 16 Lower press punch 18 Upper punch guide 20 Lower punch guide 22 Upper control cam parts 24 Lower control cam part 26 Filling equipment 28 Charging storage room 30 Filling room 32 Filling tube 34 Press equipment 36 Upper press roller 38 Lower press roller 40 Upper press roller 42 Lower press roller 44 Extrusion Equipment 46 Scraping device 48 pellets 50 Ejector 52 Control device 54 Connection Line

Claims

1. 1. A method for testing pellets in a rotary press, comprising: a rotating driven rotor having upper and lower press punches (14, 16); upper and lower punch guides (18, 20) for said upper and lower press punches (14, 16); A die plate (10) is provided between the punch guides (18, 20). Equipped with and a filling device (26) for filling the receptacle (12) of the die plate (10) with material to be compressed during a production run of the rotary press, the upper and lower press punches (14, 16) interacting with the receptacle (12) of the die plate (10) during a production run of the rotary press; a press device (34) having an upper press unit (36) and a lower press unit (38) that interact with the upper and lower press punches (14, 16) during a production run to compress material located within the receptacle (12) into pellets. The method comprises: - moving a punch pair of upper and lower press punches (14, 16) assigned to a receptacle (12) of said die plate (10) into a filling position such that said upper press punch (14) moves upwards from said receptacle (12) and said lower press punch (16) is partially located in said receptacle (12), said lower press punch (16) presetting a maximum filling height of material to be compressed in said receptacle (12); - filling the receptacle (12) with a material to be compressed; - moving the upper and lower press units (36, 38) of the press apparatus (34) relative to one another such that an expected web height of the pellets (48) produced in the press test is reached before the punch pair exceeds a position of a minimum distance between the press units (36, 38) during rotation of the rotor; the rotor enters into a rotational motion, the pair of punches contacting the press units (36, 38) in order to compress the material loaded in the receptacle (12) into pellets (48), and determining a pressing force and / or a parameter characteristic of said pressing force; When a preset pressing force and / or a preset value of a parameter characteristic of the pressing force is reached, the rotor stops and rotates in the opposite direction so that the punch pair is removed from contact with the press unit (36, 38). A method comprising:

2. 2. The method according to claim 1, characterized in that the parameters characteristic of the pressing force can be the rotational position of the rotor, the web height, the pressing force curve and / or the pressing dwell time at a preset pressing force.

3. 3. The method according to claim 1 or 2, characterized in that the pressing force and / or the parameters characteristic of the pressing force are taken into account for setting up the rotary press for a production run.

4. 4. The method according to claim 1, characterized in that during and / or after the press test, additional parameters are determined comprising the pressing force curve, the punch path curve of the upper press punch and / or the lower press punch, a maximum pressing force, the pressing dwell time at a preset pressing force and / or the web height of the produced pellets (48).

5. 5. The method of claim 4, wherein the additional parameters are taken into account for setting up the rotary press for a production run.

6. 6. A method according to claim 1, characterized in that during the press test only the punch pairs are mounted on the rotor in the receptacles (12) of the die plate (10).

7. 7. A method according to any one of claims 1 to 6, characterized in that during the press test, the filling device (26) is removed or stopped.

8. 8. The method according to claim 1, wherein in the press test, the material to be compressed is manually filled into the receptacle (12).

9. 9. The method according to claim 1, characterized in that during the press test, the rotor is driven in rotation at at least one third of the rotational speed reached during production operation of the rotary press.

10. 10. The method according to claim 1, characterized in that a number of press tests can be carried out, and that a change in the rotational speed of the rotor causes the pressing force curve and / or the punch path curve to change.

11. 11. The method according to claim 10, characterized in that a sinusoidal and / or sawtooth and / or square-wave pressure curve and / or punch path curve is set.

12. 12. The method according to claim 1, characterized in that a number of press tests are carried out, in which punch pairs with different punch head geometries and / or punch tip geometries are used.

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