Induction heating mold system

Abstract

The induction heating mold system enables rapid heating and cooling of the mold, reducing thermal cycle time, by using an induction coil in a heater module that inductively heats a ferromagnetic layer configured on the mold body, such as near the periphery of the mold body. Cooling channels can be configured between the induction coil and the ferromagnetic layer on the mold body to allow fluid to flow between the mold body and the heater module, thereby rapidly cooling the mold body for mold part ejection. Multiple heater modules that can be linked together can be used, allowing coolant to flow from one module to another through the combined cooling channels. In this manner, heater modules can be combined to provide induction heating mold systems that accommodate a variety of mold body sizes or lengths.

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of priority to U.S. Provisional Patent Application No. 63 / 118,890, filed November 28, 2020.

[0002] The present invention relates to induction heated mold systems, and more particularly to mold systems that require rapid cooling between heating cycles. [Background technology]

[0003] Many molding systems require the mold to be heated to the processing temperature before molding begins. The time required to heat the mold between cycles is part of the total processing time for production. Because this time directly impacts the manufacturing cost of the mold part, it is important to minimize this time. Furthermore, some molds require the mold to be cooled between molding cycles, for example, to allow the part to be removed without deformation or damage. In these systems, both rapid cooling and rapid heating are even more important. Heating rods and cooling channels are often configured within the mold body, or heating modules are configured around the mold body to heat the mold body by conduction. Heating modules or heating jackets can be used to heat the mold from the outside in by conduction heating. Therefore, to promote rapid heating, the gap distance between the heater module and the mold body must be kept very small. A narrow gap between the mold body and the heater module often results in long cooling times because thermal expansion can cause these parts to engage, preventing the mold body from being removed from the heater module. Therefore, heating and cooling cycles can be longer than desired. Summary of the Invention

[0004] The present invention is directed to induction heating mold systems, particularly mold systems that enable rapid heating and cooling of molds to shorten thermal cycle times. An exemplary induction heating mold system uses an induction coil within a heater module that inductively heats a ferromagnetic layer configured on the mold body, such as near the periphery of the mold body. The mold body can be made of a material with high thermal conductivity, such as copper or a copper alloy. Using a material with high thermal conductivity reduces internal temperature variations. Cooling channels can be configured between the induction coil and the ferromagnetic layer on the mold body to allow fluid to flow between the mold body and the heater module, thereby rapidly cooling the mold body for mold part ejection. An exemplary induction heating mold system can include multiple heater modules that can be linked together, allowing coolant to flow from one module to another through the associated cooling channels. In this manner, the number and / or size of heater modules can be combined to provide induction heating mold systems that accommodate a variety of mold body sizes or lengths.

[0005] An exemplary induction heating mold system can be configured to expand and stretch a parison into a balloon. Medical balloon catheters are used for a wide range of minimally invasive diagnostic and therapeutic procedures, including dilating blood vessels, opening occlusions, and delivering stents. The balloon portion of a balloon catheter is formed from a parison, which is a polymer tubular rod with a tapered end. The tube is heated, and an inflation fluid, such as air, is pumped into one end to radially expand the balloon and simultaneously stretch the balloon along its longitudinal axis, elongating the balloon. This procedure forms a thin-walled balloon with improved tensile strength. The expanded balloon is then attached to a catheter and typically compressed by a sheath for insertion into the body, such as the vasculature. The process for manufacturing an expanded balloon requires heating the parison to an expansion temperature within a mold body to a threshold temperature before stretching and expanding it. The mold body then must be cooled below the threshold temperature to remove the expanded balloon from the mold body. Rapid thermal cycling is desirable in this process.

[0006] An exemplary induction heating mold system configured for balloon fabrication of a balloon catheter may include a mold body having a cylindrical portion for receiving a parison. One end of the parison may be coupled to a source of inflation fluid, such as compressed air or nitrogen. The other end of the parison may be pinched or otherwise blocked to allow the inflation fluid to radially expand the parison. The mold body may have a ferromagnetic layer configured around its outer surface and configured to be heated by an induction heater in a heater module. A cooling channel gap between the induction heater and the ferromagnetic layer, such as along the cylindrical outer surface of the mold body, may enable rapid cooling by direct water flow onto the mold body. The cooling channel has a separation distance that is a dimension of the cooling channel aligned between the ferromagnetic layer and the heater module and / or induction coil, and this separation distance may be effectively large to enable rapid cooling. This separation distance may be about 1 mm or more, about 2 mm or more, about 3 mm or more, about 4 mm or more, about 5 mm or more, about 6 mm or more, about 8 mm or more, and any range therebetween, including the values ​​provided. Although this large separation distance is not conducive to conductive heating by the heater modules, it does allow for very rapid cooling due to the large amount of coolant that can pass over the surface of the mold body. Furthermore, this large separation distance ensures that removal of the mold body from the heater modules is not hindered by thermal expansion.

[0007] Another advantage is that the mold body does not require heating rods or cooling channels configured directly within it, which makes processing faster and easier: the mold body can simply be placed in and removed from the heater module without being attached to coolant conduits or electric heaters.

[0008] The ferromagnetic layer on the mold body is a material that can be heated by an induction coil or a rapidly changing magnetic field. Induction heating occurs within a conductive object (not necessarily magnetic steel) when the object is placed in a varying magnetic field. Induction heating is due to hysteresis and eddy current losses that occur in magnetic materials such as iron, nickel, cobalt, gadolinium, and dysprosium, as well as alloys of these materials, such as certain iron- or nickel-containing steels. The ferromagnetic layer increases the efficiency of induction heating. A thin layer of ferromagnetic material bonded to a thermally conductive material such as copper or a copper alloy offers the advantages of both high induction heating efficiency and rapid heat transfer to the mold interior. Non-ferromagnetic materials can be heated by induction heating, but the efficiency is much lower and the induction drive system is more complex. Nickel is a desirable ferromagnetic layer because of its high corrosion resistance. The ferromagnetic layer can be thin and can reach extremely high temperatures very quickly through induction heating. This extremely hot ferromagnetic layer then heats the mold body by conduction. This heating method can be much faster than conventional heating using heater modules coupled to the periphery of the mold body. The temperature of the ferromagnetic layer can be effectively increased by induction heating. The thickness of the ferromagnetic layer can be as thin as about 10 micrometers (μm) to about 500 μm, such as about 10 μm or more, about 100 μm or more, about 200 μm or more, about 300 μm or more, about 400 μm or more, and any range therebetween, including the thickness values ​​provided.

[0009] An exemplary induction heating mold system configured for balloon processing of balloon catheters can have a cylindrical mold body that forms an extension sleeve at one of both ends of the mold body. The extension sleeve can be configured to accept an end sleeve plug, which can have an opening for receiving the tapered end of the parison. The end sleeve plug can be made of a thermally conductive material, such as metal, that is heated by conduction heating from the extension sleeve. The end sleeve plug can include a material removal portion to enable rapid heating of the end sleeve plug. For example, the end sleeve plug can have a plug opening extending into the end sleeve plug along the longitudinal axis, thereby significantly reducing the mass, for example, by 1 / 5 or more, about 1 / 4 or more, about 1 / 3 or more, about 1 / 2 or more, and any range therebetween, including the provided mass reductions. The extension sleeve can be much thinner than the thickness of the mold body over its main cylindrical extension, and the ratio of the thickness of the extension sleeve to the thickness of the mold body extension can be about 1 / 4 or more, about 1 / 3 or more, about 1 / 5 or more, about 1 / 10 or more, about 1 / 20 or more, and any range therebetween, including the provided values. The thickness of the extension sleeve and the reduced mass of the end sleeve plug can be configured to allow the mold body and the end sleeve plug to heat at substantially the same rate. When heating any part, heat loss at the edges or exposed surfaces must be considered, and shaping the part to account for this can enable uniform heating. The thin extension sleeve heats much more rapidly than the mold body extension, and the heat is then transferred to the end sleeve plug. The additional interface and associated resistance between the extension sleeve and the end sleeve plug is overcome by the thinnest portion of the extension sleeve.

[0010] Insulating caps may be configured on the exposed ends of the end sleeve plugs to reduce heat loss, and the insulating caps may be made of a thermal insulating material, such as a material having a thermal conductivity of 0.5 W / (m·K) or less. Exemplary end insulating caps may be made of a high temperature resistant polymer, such as a fluoropolymer.

[0011] An exemplary heating module of an induction heating mold includes an induction coil that may be configured within a coil potting, such as epoxy. The coil potting may be electrically insulating but thermally conductive. The induction coil may be a conductive coil, such as a copper coil, that generates a magnetic field within the induction heating layer. The induction coil may be exposed to cooling channels or embedded within the coil potting. The body of the heater module may be made of metal or other thermally conductive material to facilitate cooling of the mold body between heating cycles.

[0012] The mold body can be made of a thermally conductive and durable material, such as a metal, which can be aluminum, steel, copper, a metal alloy, etc. The mold body must transfer heat from the ferromagnetic layer to the mold cavity and the part to be molded therein, such as a parison. Exemplary mold bodies have a thermal conductivity of about 100 W / (m*k) or greater, and about 200 W / (m*k) or greater.

[0013] This summary of the present invention is provided as a general introduction to some of the embodiments of the present invention and is not intended to be limiting. Additional exemplary embodiments, including variations and alternative configurations of the present invention, are provided herein.

[0014] The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention, and together with the description, serve to explain the principles of the invention. [Brief explanation of the drawings]

[0015] [Figure 1] 1 illustrates a perspective view of an exemplary mold body assembly having a mold body, an end sleeve plug, and an insulator cap. [Figure 2] 1 illustrates a cross-sectional perspective view of an exemplary mold body assembly configured between induction coils of a first modular heater assembly and a second modular heater assembly. [Figure 3]1 illustrates a perspective view of an exemplary mold body assembly configured between induction coils of a first modular heater assembly and a second modular heater assembly. [Figure 4] FIG. 1 shows a perspective view of an exemplary modular heater assembly including a first heater module and a second heater module configured around a mold body assembly. [Figure 5] A mold body assembly is shown having a mold body with an extension sleeve extending from a first end and a second end, with an end sleeve plug configured therein, and an insulator cap that seals and insulates the mold body, with a conduit extending through the entire assembly. [Figure 6] 6 shows the mold body assembly of FIG. 5 with the end sleeve plugs removed and the insulator caps removed from each end. [Figure 7] The mold body assembly of FIG. 6 is shown with a moldable object, a parison, configured within the mold cavity and extending through the first end sleeve plug and the first end insulator cap. [Figure 8] 1 illustrates an induction heated mold assembly having two heater modules each having an induction coil, wherein the mold body assembly is configured within the heater modules and has an induction heating layer. [Figure 9] 9 shows a cross-sectional view of the induction heating mold taken along line 9-9 in FIG. 8. [Figure 10] 10 shows a cross-sectional view of the induction heating mold taken along line 10-10 in FIG. 8. [Figure 11] 1 shows a graph of mold temperature versus time for nodes along the mold body and plug. [Figure 12] 1 shows a graph of mold temperature versus time when an induction heating mold having an induction heating layer or ferromagnetic layer used has an extended sleeve portion of the mold with end sleeve plugs configured therein. DETAILED DESCRIPTION OF THE INVENTION

[0016] Corresponding reference characters indicate corresponding parts throughout the several views of the drawings. The drawings represent some illustrative examples of embodiments of the present invention and should not be construed as limiting the scope of the present invention in any way. Moreover, the drawings are not necessarily to scale, and some features may be exaggerated to show details of particular components. Therefore, specific structural and functional details disclosed herein are not intended to be limiting, but should merely be construed as a representative basis for teaching those skilled in the art to variously employ the present invention.

[0017] As used herein, the words "comprises," "comprising," "includes," "including," "has," "having," or any other variation thereof, are intended to cover a non-exclusive inclusion. For example, a process, method, article, or apparatus that includes a list of elements is not necessarily limited to only those elements, but may include other elements not expressly listed or inherent in such process, method, article, or apparatus. Also, the use of "a" or "an" is used to describe elements and components described herein. This is done merely for convenience and to give a general sense of the scope of the invention. The application should be read to include one or at least one, and the singular includes the plural unless it is clear that otherwise is meant.

[0018] Certain exemplary embodiments of the present invention are described herein and illustrated in the accompanying drawings. The described embodiments are intended to be illustrative of the invention only and should not be construed as limiting the scope of the invention. Other embodiments of the invention, as well as certain modifications, combinations, and improvements of the described embodiments, will occur to those skilled in the art, and all such alternative embodiments, combinations, modifications, and improvements are within the scope of the present invention.

[0019] 1-4, an exemplary induction heated mold system 10 utilizes a mold body assembly 16 including a mold 60 configured for insertion into a heater assembly. The heater assembly may be modular, allowing two or more heater modules to be positioned adjacent to one another to heat the mold body. As shown, two heater modules 30, 40 are configured around the periphery of the mold body assembly 16 to effectively heat the mold body and the formable object therein. For longer mold bodies, additional heater modules may be added.

[0020] As shown in FIGS. 1 and 2 , an exemplary mold body assembly includes a mold body 60 having a mold sleeve portion 61 with a cylindrical conduit or mold cavity 62 extending therethrough from a mold cavity entrance 65 to a mold cavity exit 69. The mold body has an induction heating or ferromagnetic layer 68 including a ferromagnetic material. Induction coils 32 and 42 heat the ferromagnetic layer, which in turn heats the mold body 60 through conduction. The mold body includes a first extension sleeve 63 and a second extension sleeve 66 within which are configured a first end sleeve plug 70 and a second end sleeve plug 76. The extension sleeves are thin compared to the mold body wall thickness of the mold sleeve portion 61, so they heat very rapidly, allowing the sleeve plugs to conduct heat from the extension sleeves. As described herein, the ratio of the thickness of the mold sleeve portion to the thickness of the extension sleeve may be 5:1 or greater, 10:1 or greater, and any range therebetween, including the thickness ratios provided. The thickness 64 of the extension sleeve 63 and the thickness 67 of the mold sleeve portion 61 are shown in FIG.

[0021] A first end insulator cap 72 and a second end insulator cap 78 are configured on the first end sleeve plug 70 and the second end sleeve plug 76, respectively. The insulator caps are made of an insulating material having a thermal conductivity of less than 100 W / m*k, which may be a high-temperature resistant polymeric or ceramic material. As shown, portions of the first end insulator cap and the second end insulator cap are inserted into the annular portions of the first end sleeve plug and the second end sleeve plug, respectively.

[0022] Openings extend throughout the entire mold body assembly 16. First end insulator cap 72 has a cap opening 73, and second end insulator cap 78 has a cap opening 79. First end sleeve plug 70 has a plug opening 71, which may have a tapered portion for receiving and retaining the tapered portion of the parison. Second end sleeve plug 76 has a plug opening 77, which may also have a tapered portion for receiving and retaining the tapered portion of the parison. The mold body has an entrance opening 65 and an exit opening 69 to mold cavity 62. Furthermore, the mold cavity may be cylindrical in shape. The openings are aligned to receive and retain the parison for radially expanding and elongating the parison.

[0023] 3 and 4, an exemplary mold body assembly 16 is configured within the induction coils 32, 42 of a first heater module 30 and a second heater module 40. The mold body assembly, or portions thereof, can be removably attached to the modular heater assembly 14 and inserted into and removed from the mold opening 38.

[0024] As shown in Figure 1, the second end sleeve plug 76 has a plug opening 77 and a removal material opening 75 for extending the heating time. Also, as shown in Figure 2, the first end sleeve plug 70 has a tapered opening 71, and the first end insulator cap 72 has a first cap opening 73 aligned to receive the parison. Similarly, the second end sleeve plug 76 has a plug tapered opening 77, and the first end insulator cap 78 has a first cap opening 79 aligned to receive the parison.

[0025] 5-7, an exemplary mold body assembly 16 is configured to hold a parison 50, an exemplary moldable tube 15, with a first extension 55 of the parison extending through a first end sleeve plug 70 and out through a first end insulator cap 72. The parison has a first tapered end 53 held within a tapered opening 71 of the first end sleeve plug. The balloon extension 52 of the parison is configured within a mold cavity 62 of a mold body 60. As shown in FIG. 7, the parison can be configured at a first end of the mold assembly, and a second end sleeve plug and a second end insulator cap can be configured over a second extension 57 and a second tapered end 54 of the parison. Note that in some embodiments, the first end can be secured or coupled to the mold body, thereby providing a removal end. Alternatively, the parison may be constructed within the mold body assembly 16, and the entire mold body assembly may be inserted through the mold opening into the modular heater assembly.

[0026] As shown in FIG. 8 , the exemplary induction mold 10 includes a mold body assembly 16 configured within a modular heater assembly 14. A formable tube, or parison 50, is coupled to a fluid port 56 configured to inject fluid into the parison for expansion and / or stretching. A parison clamping portion 58 is configured at a second end opposite the fluid port. Induction coils 32, 42 are configured within the heater modules 30, 40, respectively, and a cooling channel 34 is configured between the induction coil and a ferromagnetic layer 68 of the mold body 60. In this embodiment, the cooling channel is a cooling annulus 35 that extends radially around the cylindrical mold body. A coolant pump 90 pumps a flow of coolant 92 from the coolant inlet 36 to the coolant outlet 37 of the first heater module 30 and from the coolant inlet 46 of the second heater module 40 through the cooling annulus 45 to the coolant outlet 47. Note that if the mold is long or large, a separate feeder or pump can be used, in which case a separate coolant would be introduced to each coolant inlet. When two or more heating modules are coupled together, as shown, the coolant can flow from module to module before exiting the modular heater assembly 14 through a terminal coolant outlet 47. An inductively heated mold assembly allows for rapid heating and cooling of the mold, increasing part throughput.

[0027] FIG. 8 illustrates an induction heating mold assembly 10 including two modular heater assemblies 14, each with an induction coil 32, and a mold body 16 assembly having a ferromagnetic layer 68, configured within the heater modules 30 and 40. A first end sleeve plug 70 is configured within the first extension sleeve 63 of the first heater module 30, and a second end sleeve plug 76 is configured within the second extension sleeve 66 of the second heater module 40. The extension sleeve plugs have a removal material opening 75, as shown in FIG. 1. This allows the end sleeve plugs to heat more rapidly due to heat loss caused by the interface between the extension sleeve and the end sleeve plug. As shown in FIG. 1, the removal material opening allows the end sleeve plugs to heat at approximately the same time as the mold body between the extension sleeves. As also shown in FIG. 8, a first end insulator cap 72 and a second end insulator cap 78 are inserted into the first end sleeve plug and the second end sleeve plug, respectively, to thermally insulate the end sleeve plugs. The cap may be made of a thermally insulating material such as a high-temperature polymer, ceramic, etc. Also shown in Figure 8 are expanders 51, 51' configured at the first and second ends of the parison to stretch the parison, as indicated by the large arrows, after the parison reaches an expansion temperature. Note that the parison may be radially expanded by the pressure of a fluid, i.e., an inflation fluid 59, introduced through an inflation port.

[0028] As shown in FIG. 9 , the induction heated mold assembly 10 includes cooling channels 34, which are cooling annuli 35 having cooling channel separations 39 extending radially between the induction coil 32 and the mold body 60 or ferromagnetic layer. The cooling channel separations are dimensioned to allow coolant flow therethrough for rapid cooling of the mold body and end sleeve plugs after a heating cycle. The induction coil can be configured within a coil potting 33, which is an electrically insulating material such as epoxy that secures the coil in place but electrically insulates it from the mold body and heater module exterior material 31. The coil potting 33 can be thermally conductive, effective for cooling the induction heated mold body assembly 10 after a heating cycle. The cooling channel separations can extend from the coil potting to the ferromagnetic material or cover layer configured thereon. As described herein, the cooling channel separations or gaps for allowing coolant flow can be 2 mm or greater, approximately 3 mm or greater, approximately 5 mm or greater, and any range therebetween, including the provided channel separations. The parison 50, or formable tube 15, is radially expanded to form the balloon 18, as shown in FIG.

[0029] As shown in FIG. 10, an end sleeve plug 70 is configured within a first extension sleeve 63 having an induction heating or ferromagnetic layer 68 thereon. The end sleeve plug has material 75 removed, such as a cylindrical opening, to reduce the amount of material that must be heated. The end sleeve plug fits snugly within the extension sleeve, but the interface creates resistance to heating, so removing material allows the temperature heating profile to match that of the mold body. While a thickness 64 of the extension sleeve is shown, it may be only a fraction of the thickness of the mold body extension. The mold body extension may be a portion of a mold having substantially the same cross section, forming a cylinder as shown herein.

[0030] Figure 11 shows a graph of mold temperature versus time for nodal points along the mold body and end sleeve plugs. Note that the end sleeve plugs shown in Figure 11 have not had any material removed and lag significantly behind the heating of the mold body extensions.

[0031] As shown in FIG. 12, the end sleeve plug has removed material as shown herein and its temperature profile closely matches that of the mold body extension.

[0032] It will be apparent to those skilled in the art that various modifications, combinations, and variations can be made in the present invention without departing from the scope of the invention. The specific embodiments, features, and elements described herein may be varied and / or combined in any suitable manner. Therefore, it is intended that the present invention cover the modifications, combinations, and variations of the invention provided they come within the scope of the appended claims and their equivalents.

Claims

1. 1. A method of forming a balloon from a parison, comprising: a) providing an induction heated mold system, the induction heated mold system comprising: a first heater module, A mold opening; An induction coil; a first heater module comprising: a mold body assembly configured within the mold opening and the induction coil, the mold body assembly comprising: a mold body that is thermally conductive; a mold cavity; a ferromagnetic layer configured around the mold body; a mold body assembly comprising: a cooling channel between the ferromagnetic layer and the induction coil, the cooling channel having a separation distance for a flow of a cooling fluid; Equipped with the ferromagnetic layer is configured to be heated by the induction coil, and the ferromagnetic layer is configured to heat the mold body by thermal conduction; b) providing a parison that is a polymeric tubular rod having a length along a longitudinal axis; c) inserting the parison into the mold cavity; d) passing a current through the induction coil, whereby the ferromagnetic layer is inductively heated to heat the mold body; e) heating the parison; f) pumping an inflation fluid into the parison to expand the parison; g) stretching the parison while it radially expands; h) pumping a coolant through the cooling channel to cool the mold body; i) removing the parison from the mold cavity, the parison after stretching having a radially expanded portion between tapered ends; A method comprising:

2. The method of claim 1 , wherein the separation distance is at least 1 mm.

3. The method of claim 1 , wherein the mold body is a thermally conductive metal.

4. 10. The method of claim 1, wherein the mold body is made of a material selected from the group consisting of copper, silver, gold, aluminum nitride, silicon carbide, tungsten, graphite, zinc, and composites thereof.

5. The method of claim 4, wherein the mold body has a thermal conductivity of at least 100 W / (m*k).

6. The method of claim 1 , wherein the mold cavity has an entrance opening.

7. The method of claim 1 , wherein the mold cavity has an entrance opening and an exit opening.

8. 8. The method of claim 7, wherein the induction heated mold system further comprises a plurality of heater modules configured for alignment, wherein a mold cavity of a first heater module is aligned with a mold cavity of a second heater module.

9. 10. The method of claim 1, wherein the induction heating mold system further comprises a plurality of heater modules configured for alignment, and wherein the flow of coolant flows from the first heater module to a second heater module having a mold opening aligned with the mold opening of the first heater module to receive the mold body.

10. 10. The method of claim 9, wherein the first heater module has a coolant inlet and a fluid cooling outlet, and the second heater module has a coolant inlet and a fluid cooling outlet, the coolant outlet of the first heater module being in fluid communication with the coolant inlet of the second heater module.

11. the mold cavity having an entrance opening and an extension sleeve configured around the entrance opening; The method of claim 1 , wherein the mold body assembly includes an end sleeve plug configured within the extension sleeve.

12. The method of claim 11 , wherein the ferromagnetic layer is configured on the extension sleeve, the ferromagnetic layer heats the extension sleeve, and the extension sleeve heats the end sleeve plug.

13. The method of claim 12 , wherein the extension sleeve is a thermally conductive material.

14. The method of claim 11 , wherein the end sleeve plug has material removal openings that increase the rate at which the end sleeve plug heats up.

15. 10. The method of claim 1, wherein the mold body includes a first extension sleeve at a first end and a second extension sleeve at a second end, and the mold body assembly includes a first end sleeve plug located at the first end.

16. 16. The method of claim 15, wherein the ferromagnetic layer is configured on the first extension sleeve, the ferromagnetic layer heats the first extension sleeve, and the first extension sleeve heats the first end sleeve plug.

17. The method of claim 15 , wherein the mold cavity includes a second end sleeve plug located at the second end.

18. 18. The method of claim 17, wherein the ferromagnetic layer is configured on the second extension sleeve, the ferromagnetic layer heats the second extension sleeve, and the second extension sleeve heats the second end sleeve plug.

19. The method of claim 1 , wherein the first end of the formable tube is coupled to an inflation port.

20. 20. The method of claim 19, wherein the moldable tube is sealed at a second sealed end.

21. The method of claim 1 , wherein the parison has a cylindrical portion and a first tapered end and a second tapered end.

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