US-20260125306-A1 - METHOD FOR SEPARATING A GLASS ELEMENT FROM A GLASS STRAND, GLASS ELEMENT AND BUNDLE OF GLASS ELEMENTS

Abstract

The present invention relates to a method for separating a glass element from a glass strand. The invention further relates to a glass element and to a bundle.

Inventors

• Christoph Bäumler
• Reiner Artmann
• André Witzmann
• Ulla Trinks
• Volker Trinks
• Stephan Tratzky

Assignees

• SCHOTT AG

Dates

Publication Date

20260507

Application Date

20230307

Priority Date

20220310

Claims (19)

1. 1 .- 19 . (canceled)
2. 20 . A method for separating a glass element from a glass strand, the method comprising: separating, at a separating location of a production site, the glass element from the glass strand, wherein separating the glass element from the glass strand comprises causing at least one specific portion of the glass strand to vibrate, wherein vibrations are transmitted to the glass strand by at least one glass strand support, in the form of at least one roller or at least one prism, which carries the glass strand at least in areas.
3. 21 . The method of claim 20 , wherein the method comprises applying a single mechanical shock impulse to the glass strand via the at least one glass strand support during or immediately after separating the glass element from the glass strand.
4. 22 . A method for separating a glass element from a glass strand, the method comprising: separating, at a separating location of a production site, the glass element from the glass strand; and causing at least one specific portion of the glass strand to vibrate at least intermittently during separating the glass element from the glass strand and/or throughout during separating the glass element from the glass strand.
5. 23 . The method of claim 22 , wherein the method comprises applying a single mechanical shock impulse to the glass strand via at least one glass strand support during or immediately after separating the glass element from the glass strand.
6. 24 . The method of claim 22 , the method further comprising: moving the glass element from the separating location to a cleaning location at the same or another production site; inserting, at the cleaning location, a nozzle head at a specific end of the glass element into the glass element and moving the nozzle head inside the glass element along a specific direction while the nozzle head does not release fluid; and releasing fluid out of the nozzle head so as to flush particles attached at an inner surface of the glass element towards the specific end as a first fluid releasing action within the glass element along a direction which is opposite to the specific direction; wherein at least during separating the glass element from the glass strand a suction of particles is carried out.
7. 25 . The method of claim 24 , wherein the method comprises releasing fluid out of the nozzle head along at least one direction pointing away from the specific end and/or along at least one direction parallel to the specific direction as a second fluid releasing action; wherein: (i) the second fluid releasing action is carried out at least intermittently while the first fluid releasing action is carried out, (ii) the second fluid releasing action is not carried out while the first fluid releasing action is not carried out, (iii) the second fluid releasing action is carried out at the same time when the first fluid releasing action is carried out, and/or (iv) the fluid is released only while moving the nozzle head within the glass element along the direction which is opposite to the specific direction.
8. 26 . The method of claim 22 , wherein at least during separating the glass element from the glass strand, the at least one specific portion of the glass strand is caused to vibrate.
9. 27 . A glass element, comprising: a hollow body portion comprising: a first end section comprising a first end of the glass element; a second end section comprising a second end of the glass element arranged opposite the first end; and a middle section arranged between the first end section and the second end section, each of the sections having an inner surface; wherein there are at least two particles deposited on the inner surface of a specific end section which particles can be identified, wherein the specific end section is the first end section or the second end section, wherein each particle of the identified particles deposited on the inner surface of the specific end section can be or is classified for the purpose of a first classification by its size in one of a plurality of classes, wherein the plurality of classes comprises two or more first classes which together entirely cover a first range of particle size of between 40 μm inclusive and a defined or definable upper boundary value exclusive, wherein each particle of the identified particles having a size falling within the first range of particle size can be or is classified in the respective first class whose range of particle size covers the respective size of the respective particle, where a mean value of the particle size of the particles which can be or are classified in the plurality of first classes is smaller than a center value of the first range of particle size.
10. 28 . The glass element of claim 27 , wherein: there are two or more first classes and/or each of the first classes has the same interval size; the plurality of classes comprises one or more second classes which together entirely cover a second range of particle size of less than 40 μm, wherein each particle of the identified particles having a size falling within the second range of particle size can be or is classified in the respective second class whose range of particle size covers the respective size of the respective particle; and/or the plurality of classes comprises one or more third classes which together entirely cover a third range of particle size which is starting from and includes the upper boundary value, wherein each particle of the identified particles having a size falling within the third range of particle size can be or is classified in the respective third class whose range of particle size covers the respective size of the respective particle.
11. 29 . The glass element of claim 28 , wherein the upper boundary value is 790 μm or less and/or more than 40 μm.
12. 30 . The glass element of claim 28 , wherein: the plurality of classes comprises three or more first classes and/or the interval size of each first class is between 40 μm and 100 μm; the plurality of classes comprises two or more second classes and/or each of the second classes has the same interval size; and/or the plurality of classes comprises two or more third classes and/or each of the third classes has the same interval size.
13. 31 . The glass element of claim 27 , wherein the first end section and/or the second end section has a length of 300 mm or less; and/or the following relation holds: O/(6*R*L)<20000/m 2 , wherein L is a length of the specific end section, R is an inner radius of the glass element, and O is the number of particles being classified in the first classes.
14. 32 . The glass element of claim 27 , wherein the glass element is free of any particles on the inner surface at the first end section and/or the second end section having a particle size of 1000 μm or more.
15. 33 . The glass element of claim 27 , wherein the identified particles are inorganic particles, glass particles and/or are selected from glass, metal, dust, and salt.
16. 34 . The glass element of claim 27 , wherein an outer diameter of the hollow body portion is 3 mm or more and/or 20 cm or less.
17. 35 . The glass element of claim 27 , wherein an inner diameter of the hollow body portion is 3 mm or more and/or 20 cm or less.
18. 36 . The glass element of claim 27 , wherein a length of the hollow body portion is 0.5 m or more and/or 2 m or less.
19. 37 . The glass element of claim 27 , wherein: the hollow body portion is at least in part designed as hollow cylindrical portion; the glass element is a glass tube; the glass element comprises a borosilicate glass, a soda lime glass, or aluminosilicate glass; the first end of the glass element is an open end and a lumen of the glass element is in fluidal communication with the environment of the glass element via the first end of the glass element, and/or the second end of the glass element is an open end and the lumen of the glass element is in fluidal communication with the environment of the glass element via the second end of the glass element; the first end of the glass element is a closed end and/or the second end of the glass element is a closed end; the glass element is or can be produced by a Danner process and/or a Vello process; and/or the glass element has been cut to length from a longer glass tube strand.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application is a national stage entry under 35 U.S.C. § 371 of International Patent Application No. PCT/EP2023/055690 entitled “METHOD FOR SEPARATING A GLASS ELEMENT FROM A GLASS STRAND, GLASS ELEMENT AND BUNDLE OF GLASS ELEMENTS,” filed on Mar. 7, 2023, which is incorporated in its entirety herein by reference. International Patent Application No. PCT/EP2023/055690 claims priority to European Patent Application No. 22161370.6 filed on Mar. 10, 2022, which is incorporated in its entirety herein by reference. BACKGROUND OF THE INVENTION 1. Technical Field of the Invention The present invention relates to a method for separating a glass element from a glass strand. The invention further relates to a glass element and to a bundle. 2. Description of the Related Art In the state of the art, glass elements such as glass tubes might be subject to the contamination. Especially particles might accumulate on the surface, especially the inner surface, of the glass element. The particles might originate for example from the manufacturing process of the respective glass element. In case of glass tubes one particularly severe source of particles is the process of confectioning the glass tubes from a glass tube strand. Here, the glass tubes might be lengthen from the glass tube strand by sawing or otherwise cutting. This comes along with the creation of a considerable amount of particles which predominantly accumulate in the region of the end sections of the glass tubes. After confectioning, the glass tubes, especially their end sections, are subsequently heated again in order to seal and shape the cutting edge. However, this might lead to the situation that the loose particles in the end regions are connected with the surface of the glass tube in a firm manner. Of course, also particles originating from other sources such as dust, educts or dirt from the environment might then be attached to the glass element during heating likewise. Such particles often cannot be removed in a subsequent cleaning procedure so that they are still present in the final glass element. Dependent on the purpose of the respective glass element, however, particles are highly undesired. For example if the glass element is intended to be used as pharmaceutical container for holding pharmaceutical compositions, a glass element of high quality, i.e. having no or almost no particles, is of particular importance. Especially particles attached to the inner surface of the glass element, such as the surface of a glass tube facing towards the lumen, are of high severity. If they get in contact with the pharmaceutical composition, the pharmaceutical composition might be contaminated either in that substances from the particles leak into the pharmaceutical composition or even that the particles as whole detach from the surface of the glass element and into the composition. In conventional manufacturing processes of for example glass tubes, thus, after lengthening and prior to heating, pressurized air is used to remove particles from the inner surface of the glass tubes. This is accomplished in that a nozzle head injects an air stream into the glass tube from one end, in order to blow particles to the other end and, hence, out of the glass tube. While this procedure is easy to implement from a technical point of view, it suffers from disadvantages. In this respect, only a portion of the air is actually injected into the glass tube, while the remainder is blown past the glass tube and might raise dust and the like in the environment. This in turn might lead to a new source of contamination. Furthermore, particles are blown from one end section to the other end section via the middle section, respectively, of the glass tube. Hence, there is the risk that this middle section afterwards is more contaminated as it initially has been the case. This is especially true since typically there are more particles in the end sections than in the middle section. It has also been noted that the high pressure leads to high noise emissions. In addition, since a laminar air flow is build up within the glass tube, the flow velocity at the inner surface of the glass tube decreases over the distance. Thus, the further the particles are located away from the end section, the lesser the interaction forces between the injected air flow and the particles becomes. Glass tubes exceeding a specific length, therefore, might not be cleaned along their entire length in a sufficient manner. SUMMARY OF THE INVENTION It is, thus, an object of the present invention to overcome the disadvantages described above with respect to the state of the art by providing means which allow for a reduction of the contamination of glass elements with particles in an easy and cost-efficient manner. It is further the object of the present invention to provide a glass element of high quality and a bundle comprising such glass elements. The problem is solved by the i