Transportation system for annealing glass containers
1. A transportation system for annealing a glass container having a barrel and two extremities, said transportation system comprising:
- a lath provided with at least two non-metallic inserts, the at least two non-metallic inserts being positioned such that, when a glass container is seated on said lath, said glass container is exclusively held by contact between said at least two non-metallic inserts and said barrel in a substantially horizontal position which is fixed relative to the lath; and
a securing element configured to reversibly firmly secure a clipping portion of said at least two non-metallic inserts into a respective slot of the lath.
The invention relates to a transportation system for annealing a glass container having a barrel and two extremities, said transportation system including a lath provided with at least two non-metallic inserts, the at least two non-metallic inserts being positioned such that, when a glass container is seated on said transportation system, said glass container is exclusively held by contact between said at least two non-metallic inserts and said barrel in substantially horizontal position which is fixed relative to the lath. The transportation system further includes securing means configured to reversibly firmly secure a clipping portion of said at least two non-metallic inserts into a respective slot of the lath.
|Process and installation for the heat treatment of cylindrical bodies, especially pipes|
Patent #US 4,628,615 A
Current AssigneeA.P.T. ANLAGEN FUR PYROTECHNIK GMBH
Sponsoring EntityA.P.T. ANLAGEN FUR PYROTECHNIK GMBH
|Shield tube supports|
Patent #US 3,885,530 A
Current AssigneeExxon Research and Engineering Company
Sponsoring EntityExxon Research and Engineering Company
- 1. A transportation system for annealing a glass container having a barrel and two extremities, said transportation system comprising:
a lath provided with at least two non-metallic inserts, the at least two non-metallic inserts being positioned such that, when a glass container is seated on said lath, said glass container is exclusively held by contact between said at least two non-metallic inserts and said barrel in a substantially horizontal position which is fixed relative to the lath; and a securing element configured to reversibly firmly secure a clipping portion of said at least two non-metallic inserts into a respective slot of the lath.
- View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12)
This application is the United States national phase of International Application No. PCT/EP2016/063685 filed Jun. 15, 2016, and claims priority to European Patent Application No. 15305931.6 filed Jun. 16, 2015, the disclosures of which are hereby incorporated in their entirety by reference.
The present invention relates to a system for carrying glass containers, in particular glass containers having a barrel and two extremities such as ampules, cartridges, syringes or vials.
The manufacturing process of glass containers generally comprises several operations such as cutting, forming and/or annealing, that are usually performed in line: the transportation of the containers is therefore required between and during each operation. Some of these operations are done at high temperatures, typically selected between 400° C. to 700° C. for the annealing step, according to the type of glass used and/or the targeted shape of the containers.
A transportation system has been described in the European Patent EP0960863 to transport glass containers during such operations, especially during heat treatment or annealing. In this prior art document, the transportation system comprises metallic laths with a triangular shaped cross-section defining a V-shaped groove when several laths are aligned. The glass containers are laid on a seat receiving one of its extremity and an insert receiving the other one. The seat where the extremity of the container is in contact with the lath corresponds to the V-shaped groove defined between two adjacent triangular cross-section laths.
However, it has been found that this prior-art system produces stress and defects in the glass material of the containers extremities. Such defects can lead to breakages during further manufacturing operations, transportation, or even use of the glass containers. This is particularly critical when the glass containers are syringes, as syringes extremities, namely the flange and the tip, that are thin and brittle areas. Breakage of syringe flanges or tips often leads to safety issues as it may prevent safe injections of pharmaceutical products.
Furthermore, this prior-art transportation system also degrades the eccentricity of the glass containers. The eccentricity parameter is an important parameter for cosmetic aspects of the glass containers as well as functional aspects when the glass containers are intended to be used for injection. Indeed, as the glass material may partially flow at the annealing temperature, glass containers may partially lose their cylindrical shape when annealed on a prior-art transportation system, thus leading to unacceptable glass containers. In the case of glass containers intended to be used for injection such as syringes or cartridges, bended containers may become non-functional by preventing the normal motion of a stopper throughout the container barrel.
Finally, the inserts described in the prior-art are permanently fixed to the metallic laths to avoid disconnection that may occur due to the vibrations and heat constraints during processing. Such permanent connections imply to design and use specific laths for each kind or size of glass containers. This requires the storage and the replacement of different laths depending on the types and dimensions of the glass containers that are manufactured. Moreover, any format changes would require adjustment of the equipment and re-validation of the machines for each modification. These constraints lead to low-efficiency and low-flexibility manufacturing processes.
There is therefore a need for a transportation system for annealing glass containers that overcomes the prior-art deficiencies.
The object of the present invention is a transportation system and a method that avoid weakening the glass containers extremities during annealing. Preferably, such a transportation system and such method allow preserving the glass containers cylindrical shape during the annealing step. Finally, a highly flexible transportation system allowing the production of all kind of glass containers in a quick and efficient way is also desirable.
This object is achieved by a transportation system for annealing a glass container having a barrel and two extremities, the transportation system comprising a lath provided with at least two non-metallic inserts. The at least two non-metallic inserts are positioned such that, when a glass container is seated on said transportation system, the glass container is exclusively held in a substantially horizontal position by contact between said at least two non-metallic inserts and said barrel, which prevents degrading the glass containers cylindrical shape. The system further comprises securing means able to reversibly firmly secure a clipping portion of said at least two non-metallic inserts into a respective slot of the lath. These securing means allow both a firm connection of the inserts to the lath and a quick customization of the transportation system according to the type and size of glass containers submitted to annealing.
In contrast to the prior-art transportation system, the transportation system according to the present invention eliminates direct contacts between the thin and brittle extremities of the glass container and the transportation system. This avoids producing stress and defects such as micro-cracks in the container extremities thus leading to a safer, stronger and more resistant glass container.
According to an embodiment, the slots are V-shaped.
According to an embodiment, the lath further comprises two side portions and the clipping portion of the inserts further comprises two abutment edges, each abutment edge being in abutment on one of the side portions of the lath, the two side portions and the abutment edges forming part of said securing means.
According to an embodiment, the securing means comprise two oblique arms protruding into the slot in tight frictional contact with a lateral edge of the clipping portion of a respective insert accommodated in the slot.
Advantageously, the inserts may be made of carbon or ceramic.
According to an embodiment, the inserts further comprise a seat portion having at least one seat intended to contact part of a glass container barrel.
Preferably, the at least one seat has a curved edge.
The lath may advantageously be made of stainless steel.
According to an embodiment, the lath further defines a longitudinal symmetry axis and the at least two parallel slots are perpendicular to said longitudinal symmetry axis.
Besides, the lath may advantageously comprise a central portion extending along a longitudinal axis of symmetry of said lath and two side portions located on both sides of said central portion, and the parallel slots extend through said central and side portions of the lath.
The invention further relates to a transportation system as described above, which further comprises glass containers having a barrel and two extremities, wherein each glass container is lying on at least two inserts only by a contact between said barrel and each of said at least two inserts.
The object of the present invention is further achieved by a method for annealing a glass container having a barrel and two extremities, the method comprising:
- providing a transportation system as described above,
- seating a glass container onto at least two non-metallic inserts firmly secured to the lath of the transportation system, so that the glass container is exclusively held by contact between said at least two non-metallic inserts and said barrel,
- carrying the at least one glass container toward an annealing oven thanks to the transportation system, said at least one glass container being motionless relative to the transportation system.
The present invention will now be described in greater detail based on the following description and the appended drawings, in which:
As visible on
The globally rectangular configuration of the lath 2 is well adapted to in-line containers manufacturing processes, in particular processes comprising annealing ovens. However, other configurations may be considered according to other manufacturing equipments or for batch manufacturing processes. In such cases, the lath may adopt, for example, a square or circular shape. Generally speaking, the central portion 2A may adopt a non-planar shape and in particular an inverted V-shape, a W-shape or a U-shape.
Several slots 21 are further present along the length of the lath. As seen on
In other embodiments, the parallel slots may have different alignments regarding the longitudinal symmetry axis A as long as they define groups of at least two parallel slots. Indeed, laths with different shapes may have different groups of at least two parallel slots oriented in different directions.
The lath 2 is made of any suitable material able to resist the mechanical and thermal conditions existing in containers manufacturing processes. Steel is a material of choice, in particular stainless steel for its resistance to thermal oxidation and warping, as for example refractory steels as AISI 310 or 316 L. Others refractory materials may also be chosen such as carbon-based composites, austenitic nickel-chromium based super-alloys (Inconel™) or Cermet (composite material composed of ceramic and metal). Optionally, a coating may be used to protect the lath material, from corrosion or wear for example. Such a coating may be selected on purpose by the skilled person, for example diamond-like carbon (DLC), titanium nitride, nickel oxide, chromium oxide or boron oxide.
As shown in
In other embodiments (not shown), the insert and their corresponding seats may present other profiles adapted to the different sizes and types of the glass containers. For example, vials may require larger seats and two-seat inserts may be more adapted, while four-seat inserts may be preferred for small size cartridges. In parallel, the number of seats per glass containers may also be adapted to the length of the glass containers under manufacturing.
Inserts are preferably made in a single piece of a non-metallic material, preferably carbon. However, they may comprise two or more materials. These materials may be chosen among refractory materials such as ceramic, in particular refractory ceramic such as steatite, alumino-silicate or zirconium oxide. Optionally, the inserts may be coated for example to protect the non-metallic material from oxidation, degradation and wear and/or to further prevent any stains, lines or microcracks on the surface of the glass containers. Such coatings may be selected on purpose by the skilled person, for example chosen among diamond-like carbon (DLC), titanium nitride, nickel oxide, chromium oxide or boron oxide.
As seen on
Furthermore, as the parallel slot 21 has the same V-shaped cross-section than the V-shaped central portion 2A, movements of the inserts in the longitudinal direction of the lath are prevented and swinging is also prohibited. The V-shaped slot 21, the oblique arms 22 and the side portion 2B of the lath together with the clipping portion 3B, the abutment edges 32 and the lateral edges 33 of the insert 3 thus act as securing means for a firm connection between the lath 2 and the insert 3. The lath itself shows a significant rigidity and a limited thermal deformation due to the specific geometry of its central V-shape portion 2A and its folded portions 2C.
Additionally, the oblique arms 22 may be easily disengaged from the clipping portion 3B with simple tools as small levers or retractors in order to quickly remove the insert 3 from the parallel slot 21. This allows a quick customization of the transportation system, for example when a different configuration of the inserts is required to manufacture glass containers of another type or size. The securing means thus allow a firm and reversible connection of the insert 3 to the lath 2.
The transportation system 1 shown in
This improvement has been demonstrated by investigating the tip resistance of 165 1 mL long syringes transported through an in-line annealing oven. Now referring to
As shown in
Additionally, the impact of the transportation system according to the present invention on the glass container eccentricity has been evaluated.
The syringes transported on a prior-art system are referred as “Standard” and the syringes transported on a transportation system according to the present invention are referred as “New”. This experiment demonstrates that the eccentricity average value decreased of about 12% when the transportation system of the present invention was used. Furthermore, the eccentricity standard deviation also decreased of 18%. This experiment thus demonstrates that glass syringes, placed horizontally on a transportation system and submitted to an annealing treatment, keep their cylindrical shape when a transportation system according to the present invention is used.
These experiments thus demonstrated the high value and the industrial feasibility of a transportation system according to the present invention.
Besides, the specific geometry of the seat 31 further contributes to the stability of the glass containers 4 when they are carried on the transportation system 1. While the beveled seat geometry of the insert 3 as shown in
Finally, the transportation system 1 according to the present invention is also very flexible as it authorizes quick configuration exchanges. Indeed, since inserts are reversibly connected to the lath thanks to the presence of the securing means, the inserts may be removed with simple tools to be replaced quickly and easily. In this way, the type and number of inserts may be changed according to the type of containers that are produced but also according to the diameter and length of the glass containers. As a result, only a limited number of laths are required to sustain the manufacturing of a wide range of glass containers. In example, a batch of vials may be annealed in a short time after a batch of cartridges.
While the best embodiment of the present invention is described above, the skilled person would be able to design various variations of the present invention.