Method and apparatus for producing a tube partially having a non-circular cross section and having circular end portions and use thereof

Patent metadata

Field	Value
Publication number	US-10227252-B2
Application number	US-201414470970-A
Country	US
Kind code	B2
Filing date	Aug 28, 2014
Priority date	Aug 30, 2013
Publication date	Mar 12, 2019
Grant date	Mar 12, 2019

Abstract

According to the invention, the tubes can be connected reliably with connecting-members or other tubes via the end portions having the circular profile using proven tube connection technologies. At the same time there is at least one central section having a non-circular cross section which is of advantage, for example for applications in photobioreactors.

First claim

What is claimed is:

1. A method for the production of a tube for conducting a medium flow for photo-bioreactors, the tube having, in sections, a non-circular profile by deforming, comprising:
a) providing a tube, which has a circular initial profile;
b) conveying the tube in a hot, malleable state through a nip, which is formed by squeezing rollers and has a first nip width, which is larger than or equal to an outer dimension of the initial profile;
c) adjusting the squeezing rollers for setting a second nip width, which is smaller than the outer dimension of the initial profile, and deforming the initial profile in said hot, malleable state for obtaining said non-circular cross section; and
d) adjusting the squeezing rollers for setting a third nip width, which is larger than or equal to the outer dimension of the initial profile, and severing said tube in a region having a circular cross section;
so that respective end portions of said tube have a circular cross section.

2. The method for the production of a tube according to claim 1 , wherein a circumferential length of said non-circular profile and the circumferential length of said end portions of said tube having a circular cross section are equal to each other.

3. The method for the production of a tube according to claim 1 , wherein a conveying length of the tube is measured, wherein an axial length of a section having said non-circular cross section and/or an axial length of transition portions between the end portions of the tube and said non-circular profile is/are adjusted on the basis of a value for the respective conveying length.

4. The method for the production of a tube according to claim 3 , wherein the adjusting of the squeezing rollers in steps c) and d) is performed according to a predetermined adjustment function for forming the transition portions between the end portions of the tube and said non-circular profile such that these transition portions have cross sections in accordance with the predetermined adjustment function.

5. The method for the production of a tube according to claim 1 , wherein the deforming of the initial profile to said non-circular profile in step c) is performed in a hot, malleable state, wherein the position of at least one of the squeezing rollers is continuously varied so that a contact area between the respective squeezing roller and the hot tube running into said nip is continuously varied.

6. The method for the production of a tube according to claim 5 , wherein the position of the respective squeezing roller is varied by a continuous axial adjustment of the respective squeezing roller.

7. The method for the production of a tube according to claim 6 , wherein the continuous axial adjustment of the respective squeezing roller is performed in accordance with a predetermined adjustment function, wherein the predetermined adjustment function
is a cyclic reciprocating movement of the respective squeezing roller, which is performed in the axial direction of said respective squeezing roller, and/or
is performed in discrete steps, each having the same step size.

8. The method for the production of a tube according to claim 1 , wherein the squeezing rollers, which form said nip, have a non-circular profile.

9. The method for the production of a tube according to claim 1 , wherein the squeezing rollers, which form said nip, have a rotationally symmetric profile and a contour, which deviates from a linear shape.

10. The method for the production of a tube according to claim 9 , wherein the squeezing rollers form a mirror-symmetric nip, wherein a contour of the respective squeezing roller comprises at least one recess or at least one projection.

11. The method for the production of a tube according to claim 1 , wherein
the squeezing rollers are driven actively and/or are heated additionally, and/or
the squeezing rollers are adjusted in axial direction and/or an angle of inclination of said the squeezing rollers is varied.

12. The method for the production of a tube according to claim 1 , wherein the tube having the circular initial profile is made of a transparent or non-transparent glass.

13. The method for the production of a tube according to claim 1 , wherein the tube having the circular initial profile is made of a transparent or non-transparent plastic material, wherein the plastic material is selected from a group consisting of: polymethylmethacrylate (PMMA), polycarbonate (PC), polyamide (PA), polyethylene (PE) polypropylene (PP), polystyrol (PS), poly-4-methylpentene-1 (PMP), polyvinylchloride (PVC), cycloolefincopolymer (COC), styrol/butadiene/styrol-bolckpolymer (SBS), methylmethacrylate/acrylnitrile/polybutadiene/styrolpfropfcopoylmere (MABS), aromatic polyesters (APE), polyestercarbonate (PEC), cellulose propionate (CP), polyetherfluorethylene (PTFE), polyethersulfone (PES).

14. A method for the production of a tube for conducting a medium flow for photo-bioreactors, the tube having, in sections, a non-circular profile by deforming, comprising:
a) providing a tube, which has a circular initial profile;
b) conveying the tube in a hot, malleable state through a nip, which is formed by squeezing rollers and has a first nip width, which is larger than or equal to an outer dimension of the initial profile;
c) adjusting the squeezing rollers for setting a second nip width, which is smaller than the outer dimension of the initial profile, and deforming the initial profile in said hot, malleable state for obtaining said non-circular cross section; and
d) adjusting the squeezing rollers for setting a third nip width, which is larger than or equal to the outer dimension of the initial profile, and severing said tube in a region having a circular cross section;
so that respective end portions of said tube have a circular cross section, and
wherein the tube has a diameter in the circular section that is greater than 8 millimeters.

Assignees

• Schott Ag

Inventors

• Schultz Nikolaus
• Katsikis Nikolaos
• Trinks Volker
• Maennl Reinhard

Classifications

• C03B23/095

  by rolling · CPC title

• B29C53/086 Primary

  bending radially, i.e. deformig the cross-section of the tube · CPC title

• C03B23/055 Primary

  by rolling {(C03B23/095 takes precedence)} · CPC title

• G01B11/12

  internal diameters · CPC title

• C03B23/045

  Tools or apparatus specially adapted for re-forming tubes or rods in general, e.g. glass lathes, chucks (C03B23/043 takes precedence) · CPC title