Systems and methods for minimizing SHR from piercing during pharmaceutical part converting using a gas flow

Patent metadata

Field	Value
Publication number	US-11420893-B2
Application number	US-201816197187-A
Country	US
Kind code	B2
Filing date	Nov 20, 2018
Priority date	Nov 30, 2017
Publication date	Aug 23, 2022
Grant date	Aug 23, 2022

Abstract

Systems for producing articles from glass tube include a converter having a base with a plurality of processing stations and a turret moveable relative to the base. The turret indexes a plurality of holders for holding the glass tubes successively through the processing stations. The systems further include a gas flow system or a suction system for producing a flow of gas through the glass tube during one or more heating, forming, separating or piercing operations. The flow of gas through the glass tube produced by the gas flow system or suction system may be sufficient to evacuate or purge volatile constituents of the glass from the glass tube and/or pierce a meniscus formed on the glass tube during separation, thereby reducing the Surface Hydrolytic Response (SHR) of the interior surface of the glass tube and articles made therefrom.

First claim

What is claimed is:

1. A system for producing glass articles from glass tubing comprising:
a converter including a plurality of processing stations, a base, a main turret, and a secondary turret, wherein:
the plurality of processing stations comprise at least one heating station, at least one forming station, and a separating station;
the converter is operable to index a glass tube through the plurality of processing stations; and
the main turret comprises the at least one heating station, the at least one forming station, and the separating station; and

a gas flow system comprising:
a manifold fluidly couplable to a gas source; and
a plurality of glass tube connectors, each glass tube connector removably coupleable to a distal end of the glass tube and fluidly coupled to the manifold by a conduit, wherein:
the manifold is separate from and positioned above the base and the main turret;
the manifold comprises an inner ring having a gas supply channel and an outer ring surrounding the inner ring and rotatable with the main turret relative to the inner ring;
when each glass tube connector is coupled to the glass tube, at least a portion of the glass tube connector is disposed inside of the glass tube; and
for at least one of the glass tube connectors, the gas flow system is operable to pass a gas from the manifold, through the conduit, through the glass tube connector, and into the glass tube through the distal end of the glass tube, and wherein passing the gas into the distal end of the glass tube produces a flow of gas adjacent to a proximal end of the glass tube, the flow of gas operable to remove at least a portion of an atmosphere from an interior of the glass tube and reduce contamination of an inner surface of the glass tube by alkali released from the glass tube.

2. The system of claim 1 , wherein the gas flow system is operable to deliver a gas pulse to the distal end of the glass tube.

3. The system of claim 2 , wherein the gas pulse has a duration less than a sum of an index time and a dwell time of the converter.

4. The system of claim 2 , wherein the separating station is a thermal separating station and the gas pulse is sufficient to open a meniscus of glass formed at the proximal end of the glass tube during thermal separation.

5. The system of claim 1 , wherein each of the plurality of glass tube connectors includes a central bore extending axially through the glass tube connector and a swivel connector disposed at least partially within the central bore, wherein the swivel connector allows the glass tube to rotate relative to the manifold, and the interference fit between the glass tube connector and the glass tube maintains the orientation of the glass tube connector relative to the glass tube during rotation of the glass tube.

6. The system of claim 1 , wherein the manifold comprises a plurality of valves, each of the plurality of valves fluidly coupled to one of the plurality of glass tube connectors.

7. The system of claim 6 , wherein the manifold comprises a plurality of valve actuators, each of the plurality of valve actuators operatively coupled to one of the plurality of valves, wherein each valve actuator is operable to open and close the associated valve to deliver the gas pulse to the distal end of the glass tube.

8. The system of claim 1 , further comprising at least one flow meter fluidly coupled to the manifold and operable to measure a flow rate or a total flow of the gas pulse to the distal end of the glass tube.

9. The system of claim 1 , wherein the gas flow system further comprises at least one flow controller operable to vary a flow rate of the gas in response to changes in a length of the glass tube.

10. The system of claim 1 , wherein the manifold comprises:
an inner ring having a gas supply channel; and
an outer ring surrounding the inner ring and rotatable with a main turret of the converter relative to the inner ring, the outer ring having a plurality of gas delivery channels, each of the gas delivery channels fluidly coupled to one of the plurality of glass tube connectors;
wherein the manifold is operable to align one of the plurality of gas delivery channels of the outer ring with the gas supply channel of the inner ring to fluidly couple one of the plurality of glass tubes to the gas source.

11. A method for producing an article from a glass tube having an inner surface comprising:
introducing the glass tube to the system of claim 1 for producing glass articles from glass tubing;
heating the proximal end of the glass tube at the at least one heating station, wherein alkali is released from the glass tube during the heating;
forming at least one feature of the article at the proximal end of the glass tube in the at least one forming station;
separating the article from the proximal end of the glass tube at a separating station; and
introducing the flow of gas into the glass tube through the distal end of the glass tube by the gas flow system of the system of claim 1 .

12. The method of claim 11 , wherein separating the article from the glass tube comprises thermal separation that produces a meniscus of glass across the proximal end of the glass tube and wherein the flow of gas adjacent to the proximal end of the glass tube is sufficient to open the meniscus.

13. The method of claim 11 , wherein introducing the flow of gas comprises introducing a gas pulse to the distal end of the glass tube.

14. The method of claim 13 , wherein the gas pulse has a duration less than the sum of a dwell time and an index time of the converter.

15. The method of claim 13 , wherein separating the article from the glass tube comprises thermal separation that produces a meniscus of glass across the proximal end of the glass tube and wherein the gas pulse is sufficient to open the meniscus.

16. The method of claim 13 , wherein a plurality of gas pulses are introduced to the distal end of the glass tube.

17. The method of claim 13 , further comprising controlling at least one of a duration of the gas pulse, a pressure of the gas pulse, or a volume flow rate of the gas pulse in response to changes in a length of the glass tube.

18. The method of claim 13 , further comprising controlling at least one of a duration of the gas pulse, a pressure of the gas pulse, or a volume flow rate of the gas pulse in response to changes in the tube diameter, wall thickness, glass type, converter operating temperatures, or combinations of these.

19. The method of claim 11 , comprising introducing the flow of gas to the distal end of the glass tube when the glass tube is positioned in one of the plurality of processing stations.

20. A system for producing glass articles from glass tubing comprising:
a converter comprising a plurality of processing stations, a base, a main turret, and a secondary turret, wherein:
the plurality of processing stations comprise at least one heating station, at least one forming station, and a separating station;
the main turret comprises the at least one heating station, the at least one forming station, and the separating station; and
the converter is operable to index a glass tube through the plurality of processing stations; and

a gas flow system comprising:
a manifold fluidly coupleable to a gas source, wherein:
the manifold is separate from and positioned above the base and the main turret; and
the manifold comprises an inner ring having a gas supply channel and an outer ring surrounding the inner ring and rotatable with the main turret of the converter

Assignees

• Corning Inc

Inventors

• Mcenroe David John

Classifications

• C03B7/01

  Means for taking-off charges of molten glass {(C03B7/08, C03B7/14 - C03B7/22 take precedence)} · CPC title

• C03B23/099

  by fusing, e.g. flame sealing · CPC title

• C03B23/09

  Reshaping the ends, e.g. as grooves, threads or mouths · CPC title

• C03B35/26

  Transporting of glass tubes or rods · CPC title

• C03B33/06 Primary

  Cutting or splitting glass tubes, rods, or hollow products (C03B33/09 takes precedence) · CPC title