WO1990009745A1 - Method of forming a custom inner ski boot liner or the like - Google Patents

Abstract

A method of forming a custom ski boot liner. The method includes the steps of forming cast (41) closely conforming to the foot (21) of a user at a first location, preferably while the foot is in a substantially unconfined state. The method further includes the steps of removing the cast (45) from the foot (21) at the first location, transporting the cast to a second liner forming location, making a rigid custom last from the cast at the second location, mounting the rigid custom last inside a rigid boot form (45) in spaced relation thereto to define a liner volume, maintaining the relative positions of the rigid cast and boot form (45) and forming in place in the liner volume a resinous foam (47) which substantially fills the liner volume to a controlled density, resiliency and pliability. The last step of the method is to remove the last from inside the dimensionally stable resinous foam (47), usually by removing the liner and last from the shell and thereafter removing the last from the liner and mounting the liner into a ski boot or the like.

Description

METHOD OF FORMING A CUSTOM INNER

SKI BOOT LINER OR THE LIKE

TECHNICAL FIELD

The present invention relates, in general, to methods for forming ski boot liners or bladders, and more particularly, relates to methods for forming in place foamed ski boot liners.

BACKGROUND ART

Considerable effort has been directed toward the manufacture of resilient bladders or liners for ski boots or the like. Such liners generally conform to the shape of the user's foot and have an outside surface which conforms generally to the shape of a hard, relatively rigid ski boot shell. The ski boot liner should hold the wearer's foot in a desired biomechanical condition relative to the boot, while still maintaining sufficient pliability, softness and resiliency to be comfortable during skiing.

Two approaches to the formation of foamed-in-place ski boot liners have generally been employed. The first of these approaches is to foam the liner in place inside the ski boot or a form replicating the ski boot while the user's foot is inside the boot or form. Thus, the user sits with his foot in the form during the foaming process. Typical of such an approach is the ski boot liner forming process set forth in U. S. Patent No. 3,640,003.

While the approach of foaming a liner around the user's foot has the substantial advantage of great conformance of the liner to the user's foot, there are also a number of disadvantages. First, depending upon the density of the foamed liner, the foaming process generates significant pressure which will distort and compress the soft tissues of the foot during the foaming process. Accordingly, the liner conforms closely to a somewhat deformed and compressed foot.

Second, the formation of foamed ski boot liners requires reasonably close control of the foaming process. Thus, foamed liners formed at sea level, for example, will have different characteristics than foamed liners formed with the same chemicals at 7,000 or 8,000 feet. Similarly, humidity and other environmental factors can significantly affect the resultant liner. When a ski boot liner is foamed in place directly around the wearer's foot, such foaming usually will have to take place at the ski shop or retail outlet for ski boots. Thus, a plurality of ski boot outlets at differing elevations and environmental conditions will result in ski boot bladders having strength, resiliency and softness which varies undesirably. Moreover, the technique of a plurality of different ski shop boot mechanics will vary substantially, with the further introduction of variations in quality of the resulting liner. A third disadvantage is that it is difficult to foam a ski boot liner in place around a user's foot and also include a layer underneath the plantar surface of the foot. As will be seen in U.S. Patent No. 3,640,003, the foot rests on the lower surface of the boot shell and foam extends around the edges of the foot only. While there are techniques for supporting the foot and liners can be combined with separate inner sole members, an integrally formed layer under the plantar surface is difficult to create when the liner is foamed directly around the user's foot.

Another disadvantage of foaming a liner in place around a user's foot is that it is difficult to control or maintain a steady, biomechanically sound, position of the user's foot during the foaming process.

In light of the difficulties with foaming bladders in place around the user's foot, a more common process is to employ a mandrel or last for the user's foot and foam the liner in a factory where the foaming conditions can be controlled. Typical of such ski boot liner forming processes are the methods set forth in u.s. Patent Nos. 4,182,056, 3,896,202 and

4,414,762. Forming a ski boot liner around a mandrel or last at a factory enhances the liner quality by being able to control foaming conditions, but the resulting liner does not have a custom fit to the individual user. The mandrels or lasts are comprised of a series of replicas of normal or average feet of varying size. The resiliency of the liner is employed to attempt to make up for the variations of the individual's foot from the casting last or mandrel.

Another ski boot bladder is shown in U.S. Patent No. 3,760,056 in which a combination of foam material and pneumatic cushions is used to try to adapt to the variations in individual's feet. Accordingly, it is an object of the present invention to provide a method for forming a ski boot liner which is customized or replicates the user's foot and yet can be manufactured under controlled factory conditions.

Another object of the present invention is to provide a custom ski boot liner having improved conformance to the wearer's foot.

Still another object of the present invention is to provide a ski boot liner forming method which does not undesirably distort the soft tissues of the user's foot during the formation process.

Still a further object of the present invention is to provide a method for forming a ski boot liner which is suitable for use by relatively unskilled personnel at a plurality of ski boot sales outlets and at the same time for use by relatively skilled liner manufacturing personnel at a central liner manufacturing facility, Another object of the present invention is to provide a ski boot liner process or method which produces enhanced uniformity of the resulting liner without undesirably increasing the cost of liner manufacture.

The ski boot liner manufacturing method of the present invention has other objects and features of advantage which will become apparent from or as set forth in more detail in the accompanying drawing and the following description of the best mode of carrying out the invention. DISCLOSURE OF INVENTION The method of forming a custom ski boot liner of the present invention is comprised, briefly, of the steps of forming a cast of a foot while the foot is in a substantially unconfined state, removing the cast from the foot, forming a relatively rigid custom last from said cast, placing the rigid custom last inside a relatively rigid boot shell to define a liner volume therebetween, introducing a liner material capable of setting into a dimensionally stable form into the liner volume and containing the material in the volume until a dimensionally stable liner is formed and thereafter removing the last from inside the liner. In another aspect of the method of the present invention, the method includes the steps of, at a first location, making a casting conforming closely to the foot of the user and thereafter removing the casting from the foot, modifying the cast to become a rigid custom last from the casting at one of the first location and a second location, transporting the casting or the rigid custom last from the first location to the second location, at the second location, mounting the rigid custom last inside a rigid boot form to define a liner volume therebetween, maintaining the last in a predetermined relationship to the boot form and forming in place in the liner volume a resinous foam which substantially fills the liner volume and has a controlled density, resiliency and pliability, and thereafter removing the rigid last from inside the resinous foam. BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a side elevation view of a foot having a liner mounted thereon and a casting fabric sock positioned adjacent thereto as a first step in a method in accordance with the present invention. FIG. 1B is a side elevation view corresponding to FIG. 1A showing the casting sock mounted on the foot.

FIG. 1C is a side elevation view corresponding to Fig. 1A with the hardened fabric sock removed from the foot.

FIG. 2 is a side elevation view corresponding to FIG. 1A and showing the casting of FIG. 1C made into a rigid custom last.

FIG. 3A iε a side elevation view corresponding to FIG. 1A of the last of FIG. 2 positioned inside a boot shell.

FIG. 3B is a side elevation view corresponding to FIG. 3A showing a liner material foamed between the custom last and boot shell. FIG. 3C is a slightly enlarged, side elevation view corresponding to FIG. 3B with the liner and custom last removed from the boot shell.

FIG. 4 is a top perspective view of a ski boot liner formed in accordance with the method of the present invention with the custom last removed.

BEST MODE OF CARRYING OUT THE INVENTION

The ski boot liner manufacturing method or process of the present invention is based upon an approach in which a custom casting replicating the user's foot is made at a ski shop or boot sales outlet and the casting is then sent to a factory for the controlled manufacturing of the liner at the factory using a rigid last formed from the casting. This approach enables the resultant liner to have a custom fit to the individual user and a greatly enhanced quality and uniformity aε a result of performance of the foaming by skilled personnel at a factory location having known environmental conditions. In the method of the present invention as illustrated by the drawing, the steps shown in FIGS. 1A, 1B and 1C are generally performed at a ski shop. The step shown in FIG. 2 may be performed at the ski shop or at the factory, and the steps performed in FIGS. 3A, 3B, 3C and 4 are performed at a liner manufacturing facility.

The first step of the method of the present invention is the step of forming a cast of a user's foot. Casting feet to form custom footwear is broadly wall known. U.S. Patent NOs. 3,995,002, 2,961,714, 2,955,326, 2,907,067, 2,894,288, 2,856,633, 2,593,742 and 1,647,639 are illustrative of various foot casting techniques known in the prior art. The particular foot casting method or technique employed is not regarded as being critical to the method of the present invention, and many prior foot casting techniques can be adapted for use with the liner forming method of the present invention.

It is preferable, however, to use a foot casting technique or process which produces a very good replica of the foot while being suitable for use by relatively unskilled ski shop personnel at minimal cost. Such a foot casting technique is shown in

FIGS. 1A, 1B and 1C of the drawing. Mounted on foot 21 is a very thin sock, bag or envelope 23 which will protect the foot from resins used in the casting process and facilitate removal of the cast from the foot. Envelope 23 can be a protective thin polyester knit stockinette or a plastic film bag which is inert to the resins used in the casting process. In order to further facilitate removal of the casting from the foot, wire means 25 is taped or held next to the foot while envelope 23 is pulled over the wire means. An end 29 can be poked through the thin plastic envelope 23, while a second end 33 extends out of the open end of envelope 23. Wire means 25 should be sufficiently thin and strong to enable subsequent cutting through of the fibers in fabric sock 31 after they have been hardened by a resin. A high tensile strength stainless steel harpsichord wire having a diameter of about 0.02 inches is well suited for this purpose.

Fabric tube 31 has a closed first end 35 and an open second end 37, and the second end can be seen to be rolled into a doughnut or toroidal shape 39 prior to mounting of the tubular fabric member onto foot 21.

A fabric particularly well suited for the casting of a foot is a standard polyester rib-knit stockinette having a thickness of approximately 1 mm. In the preferred form a water-curable, isocyanate-functional prepolymer is impregnated into or coated onto fabric sock 31.

In order to form a cast of the foot, doughnut-shaped tubular sock 31 is first dipped into ambient water, and the excess water is squeezed off. The doughnut is then stretched over the toe area 39 of the foot and unrolled onto the foot. Wire end 29 can be poked through the casting sock fabric, as shown in FIGURE 1A. The length of fabric sock 31 can be selected in accordance with the desired height of the liner to be produced.

The resin content of the impregnated tubular sock is preferably between about 40% and about 80%, with about 65% being preferred. The tubular sock is rolled over protective envelope 23 and wire 25. sock material 31 should be sufficiently resilient so that it will conform closely to foot 21 with minimal easing or manipulation of the material. Tubular knit polyester fabrics having an extensibility of over 100% in at least one direction are suitable for this use, and fabrics comprising lofted glass yarn with elastomeric fibers laid-in repeating courses to provide resiliency are most preferred.

It should be noted that prior to rolling the tubular casting sock 31 over foot 21, pads, shields or the like can be secured in place on the foot or envelope to modify the foot shape to accommodate deformities.

In order to form a casting of the foot in the most desirable biomechanical position, it is further preferred that foot 21 be manipulated to and maintained in a neutral position during hardening of the water-curable resin. The "neutral position" of the foot is when the rear bone complex of the foot is rotated approximately one-third to one-half of the distance from full pronation to full supination of the rearfoot bone complex. The foot is neither pronated nor supinated when in the "neutral position." Apparatus for maintaining the foot in the neutral position while casting the same is set forth in our U.S. Patent No. 4,662,079. This results in a cast which not only conforms to the foot, but conforms to the foot when it is in the best biomechanical position, which further enhances the resulting liner made using the process of the present invention. Once the resin impregnated sock has cured or hardened, for example about 3 to 5 minutes, the step of removing the casting from the foot can be performed. wire 25 provides a cast removal method that eliminates the need for hazardous cast cutting using shears or cast saws. Instead, ends 29 and 33 of wire means 25 can be gripped and inserted through holes in metal rolling pin, not shown. The rolling pin is then rolled up the cast to wrap the wires around the same and pull wire 25 through the thin plastic envelope 23 and the hardened fibers in the resin impregnated fabric cast.

As best may be seen in FIG. 1C, wire 25 forms a slit 27 in the casting 41 which allows the halves of the casting to be opened to permit withdrawal of the foot from inside envelope 23. The result is a hollow hardened casting or shell which replicates closely foot 21 when the foot is in a desired biomechanical condition, for example the neutral position. Protective envelope 23 normally will be bonded to the inside of the fabric shell or casting 41, and the upper end which protrudes from the shell can be easily trimmed off or merely pushed down into the interior of shell 41. The resulting product in FIG. 1C is a cast of the foot which is reasonably hard and dimensionally stable. The thin nature of the fabric tube used to form the cast, as well as the unitary and seam-free structure, enables the exterior of cast 41 to be used ae last for formation of the ski boot liner. Moreover, the relatively hard and rigid nature of cast 41 allows to be easily transported without danger of being damaged or distorted.

Accordingly, the steps thus far described and illustrated in Figs. 1A, 1B and 1C are all preferably performed at boot sales outlets, such as ski shops. It is further possible to form a rigid custom last, generally designated 43, as shown in FIG. 2 at either the individual ski shops or at a central liner manufacturing facility. Since it is highly desirable to be able to accurately index last 43 with respect to a boot shell, generally designated 45 (FIGS. 3A and 3B), it is preferred that the custom last forming step of the present invention be performed at the liner manufacturing location, or at an authorized trained dealer with trained and licensed personnel and known environmental conditions.

Last forming step will include rigidifying the shell foot cast 41 so that it will be capable of withstanding substantial external pressure. Depending upon the pressure generated during the foaming step, the cast 41 can simply be glued together along slit 27 to rigidify the same, or it may further be filled with a foam material 47, as shown in FIG. 2. Foam 47 can be a foam selected from a group consisting of isotatic foams and syntatic foams.

Additionally, during the last forming step it is further preferable to add a toe extension 49 to casting 41 and to mount indexing means for the last, such as rod 51, to custom last 43, for example, by foaming foam 47 around rod 51. Last 43 also may be modified to accommodate foot deformities such as bunions, hammertoes, etc. prior to injection molding in order to relieve pressure in such areas when the foot is positioned in the ski boot.

Still further, reinforcing and or cushioning socks or materials can be fitted to last 43 prior to foaming the liner. Such socks or materials serve to stabilize the completed liner or bladder in particular areas and these materials will be embedded in the foam. Once a rigid, stabilized custom last 43 of foot 21 is formed, the process of the present invention includes the step of placing last 43 inside a relatively rigid boot shell 45 with at least a portion of exterior surface 53 mounted in relatively spaced relation to a portion of interior surface 55 of shell 45. This spacing defines a liner volume 57 between the last and shell.

As it can be seen from FIG. 3A, shell 45 can have an interior surface 55 which includes various, liner shape effecting surfaces. Thus, the bottom inner surface 59 can be sloped so as to cant the liner in a forward direction, common to ski boot constructions. Additionally, protrusions 61 can be provided to provide relief areas in the liner accommodating the buckle structure or pressure from the interior such as ankle bone area 24.

The boot shell means 45 can, if desired, actually be the final ski boot in which the liner is to be mounted. Alternatively, shell means 45 can be a form from which the liner must be removed and thereafter placed in a ski boot. If shell 45 is merely a boot form, the liner produced therein has to be removed, and if it is a ski boot, it may be desirable to be able to remove the liner. Accordingly, a release layer is usually positioned along interior surface 55 of the shell so as to permit release of the formed liner for removal. In order to achieve the best biomechanical orientation of the last, to obtain the desired liner thickness and to provide a plantar support area, it is further preferable that last 43 be mounted in a controlled or indexed relation to shell 45. Thus, the mounting rod 51 can be placed in a fixture such as arm 63 and collar 65 which are mounted to a rigid support 67. Similarly, the shell 45 is mounted to a rigid support surface 69 by clamps 71 so that precise reproducible indexing of last 43, for example, in a forwardly canted position, can be achieved.

Alternatively, last positioning blocks, spacers, or wedges 70 (FIGURE 3A) can be placed between last 43 and shell 45. Following injection molding of the liner and curing the spacers or blocks 70 would be cast into the liner and accordingly are preferably formed of a foam which is compatable and comparable in characteristics to the liner foam. Normally, spacers 70 and support arm 63 are not both required to position the last, but a combination can be used to insure precision of location of the last.

Additionally, and very importantly, it is possible to position last 43 in upwardly spaced relation to internal surface 59 of shell 45. This spacing allows the liner to have a plantar support volume 73 (FIG. 3B) underneath the plantar surface of last 43.

As shown in FIG. 3B, the process of the present invention next includes the step of introducing a liner material 77 into liner volume 57. Liner material 77 must be capable of setting or curing into a dimensionally stable form suitable for use as a liner. Liquid resin reaction mixtures which produce a pliant foam are preferred. Resins are well known in the art for making ski boot liners, for example as described in the polyurethane foam system of U.S. Patent No. 3,581,412, although other polyurethane, silicone rubber or analogous reaction or foam forming mixtures also can be used. Most usually, the introducing step is accomplished by injecting the liquid reaction mixture into liner volume 57 and allowing the mixture to react or foam in place in the liner volume while contained by the rigid boot shell form and rigid custom last. Depending upon the resiliency, thermal insulation and the density of the foam desired, an upper end closure means 79 will be mounted so as to enclose and contain liner volume 57 completely. Some foam materials can be foamed in place in an open mold or liner volume. Once the liner material 77 has set into a dimensionally stable condition, the next step of the process of the present invention is to remove custom last 43 from inside the foamed liner, generally designated 81 and best seen in FIGS. 3C and 4. Removal of the last from the liner can most easily be accomplished by first removing the last and liner from shell 45. This can be accomplished by forming shell 45 as a split shell or with an opening at the side or area of the tongue, if shell 45 is a ski boot. The shell is opened up to release the liner, and the liner and last are moved from shell 45 to produce the assembly of FIG. 3C. Last 43 can be removed from the interior of liner 81 in a similar manner. A slit or front opening generally designated 83 can be provided in the front of the liner, either by slitting the liner material 77 or by using an opening or slit-forming removable insert during the foaming process. Opening up of the liner will allow, in combination with the pliant, usually resilient nature of the most preferred liner foams, to pull last 43 out of the liner. The result is the liner of FIG. 4, which can now be trimmed, otherwise finished and inserted into a ski boot shell. It will be seen from FIG. 4 that buckle receiving recesses 85 and 87 and ankle recess 89 have been formed in the liner as a result of protrusions provided on interior surface, 55 of the boot shell form. The upper edge 89 also can be cast or trimmed to a variety of shapes as conventionally used to best cushion the calf and shin of the ski boot wearer.

Positioning of the liner back in a boot can also be accompanied by adjustments of the boot to best biomechanically position the combination of the foot and the liner inside the shell, for example, as described in U.S. Patent No. 4,567,617. Since the liner is custom fitting and biomechanically cast, boot shell adjustments can be minimized.

Ski boot liners manufactured in accordance with the method of the present invention have substantially enhanced quality without increased cost. Since the steps of FIGS. 3A, 3B and 3C all are performed at a central liner fabricating location, the foaming system used in the liner can be set up very accurately to produce the desired foam density, resiliency, insulating properties and strength under the atmospheric conditions of the particular manufacturing location. There is no need, for example, to adjust or modify the resinous reaction mixture to accommodate a multiplicity of differing liner foaming environments. The process of the present invention allows the foot casting steps to be accomplished at a plurality of first locations, ski shops or the like, and then shipped to a central second location, the liner fabricating facility. The casting steps are not environmentally sensitive since water-curable hardening resins are relatively insensitive to environmental changes within the normal range of environmental conditions. The environmentally sensitive in situ foaming, however, is centralized in the process of the present invention to enable its close control.

Moreover, the liner foaming steps can be factory accomplished by relatively skilled personnel doing a high volume of liners to thereby increase fabrication and efficiency and decrease fabrication costs.

Claims

WHAT IS CLAIMED IS:

1. A method of forming a custom ski boot liner or the like comprising the steps of:

a. forming a cast of a foot while said foot is in a substantially unconfined state;

b. removing said cast from said foot;

c. forming a relatively rigid custom last from said cast;

d. placing said rigid custom last inside a relatively rigid boot shell means with at least a portion of an exterior surface of said rigid custom last in spaced relation to at least a portion of an interior surface of said shell means to define a liner volume therebetween;

e. introducing a liner material capable of setting to a dimensionally stable form into said liner volume, and holding said liner material in said liner volume until a dimensionally stable liner is formed in said liner volume; and

f. thereafter removing said rigid custom last from inside said stable liner and from inside said shell.

2. The method of forming a custom ski boot liner as defined in claim 1, and the steps of:

removing said stable liner from said shell means;

mounting said stable liner inside a ski boot.

3. The method of forming a custom ski boot liner as defined in claim 1 wherein,

said placing step is accomplished by placing said rigid custom last inside a ski boot shell to form said stable liner directly inside said ski boot Shell.

4. The method of forming a custom ski boot liner as defined in claim 1 wherein,

said introducing step is accomplished by injecting a foam forming material into said liner volume and foaming said liner in place in said liner volume while contained by said rigid custom last and said shell means.

5. The method of forming a custom ski boot liner as defined in claim 1 wherein,

said introducing step is accomplished by injecting a liquid resin reaction mixture into said liner volume.

6. The method of forming a custom ski boot liner as defined in claim 5 wherein,

said liquid resin reaction mixture forms a dimensionally stable pliable resinous foam.

7. The method of forming a custom ski boot liner as defined in claim 1 wherein,

said step of forming a cast is accomplished by applying a thin fabric tube impregnated with a liquid resin to said foot, said fabric having sufficient resiliency and strength to substantially conform to said foot with minimal manipulation during casting, and thereafter hardening said resin to form a rigid uniform thin cast of said foot.

8. The method of forming a custom ski boot liner as defined in claim 7 wherein,

prior to said applying step, positioning wire means against said foot to extend beneath said fabric tube from proximate one end to proximate another end of said fabric tube upon application of said fabric tube to said foot; and

after said hardening step, pulling said wire means up through said fabric tube to effect said step of removing said cast from said foot.

9. The method of forming a custom ski boot liner as defined in claim 1 wherein,

during said placing step, positioning said rigid custom last in a predetermined biomechanically desired position inside said shell means, and

during said introducing step, maintaining said rigid custom last in said desired position until said dimensionally stable liner is formed.

10. The method of forming a custom ski boot liner as defined in claim 9 wherein,

said rigid custom last is positioned in said shell means with a plantar surface thereof in spaced relation to an inner plantar support surface of said shell means to provide a stable liner having a plantar support volume.

11. The method of forming a custom ski boot liner as defined in claim 1 wherein,

said step of forming a cast is accomplished by casting said foot while said foot is maintained in a neutral position.

12. The method of forming a custom ski boot liner as defined in claim 1 wherein,

said introducing step is accomplished by injecting a liquid resinous pliant foam forming material into said liner volume; and

said step of removing said rigid custom last is accomplished by removing said last and stable liner from said shell means and thereafter removing said stable liner from said rigid custom last.

13. The method of forming a custom ski boot liner as defined in claim 12 wherein,

said stable liner is removed from said last by slitting said stable liner.

14. The method of forming a ski boot liner comprising the steps of:

a. making a casting of a user's foot by mounting a resin impregnated, thin tubular fabric on said foot, said fabric being sufficiently resilient to substantially uniformly conform to said foot in a thin layer, rigidifying said resin to make a casting of sufficient strength and rigidity to act as a rigid last, and removing said casting from said foot,

b. using an exterior surface of said casting as a custom last;

c. positioning said custom last in a predetermined spaced relation inside a rigid boot shell having a greater interior volume than the volume of said custom last to define a liner volume between said custom last and said shell form;

d. foaming a pliable resinous foam in place in said liner volume while maintaining custom last in said predetermined spaced relation to said shell; and e. after formation of said foam removing said custom last from the interior of said foam.

15. A method of forming a custom boot liner comprising the steps of:

a. at a first location, making a cast conforming closely to a foot of a user who is to use said boot liner, and once said cast is dimensionally stable, removing said cast from said foot;

b. making a rigid custom last from said cast at one of said first location and a second location; c. transporting one of said cast and said rigid custom last from said first location to a second location;

d. at said second location, mounting said rigid custom last inside a rigid boot form means with an exterior surface of said last positioned in spaced relation to at least a portion of an interior surface of said rigid boot form means to define a liner volume therebetween;

e. while maintaining said rigid custom last positioned inside said rigid boot form means in a predetermined relationship to said rigid boot form means, forming in place in said liner volume a resinous foam which substantially fills said liner volume and has a controlled density, resilience and pliability; and

f. thereafter, removing said rigid custom last from inside said resinous foam and said rigid boot form means.

16. The method as defined in claim 15 wherein, said step of making a rigid custom last is performed at said second location, and said transporting step is accomplished by transporting said cast to said second location.

17. The method as defined in claim 16 wherein, said first location is a casting facility; and said second location is a liner manufacturing facility.