US20060113309A1

US20060113309A1 - Tank assembly

Info

Publication number: US20060113309A1
Application number: US11/263,208
Authority: US
Inventors: Michael Zdroik; Mark Matheny
Original assignee: MILLENNIUM INDUSTRIES Inc
Current assignee: MILLENNIUM INDUSTRIES Inc
Priority date: 2003-06-04
Filing date: 2005-10-31
Publication date: 2006-06-01
Also published as: US20040245253A1; JP2006526542A; DE112004000958T5; WO2005000686A3; US7083065B2; WO2005000686A2; DE112004000958B4

Abstract

A tank assembly is provided. A tank assembly in accordance with the present invention includes a container having a neck portion and interior and exterior surfaces. The tank assembly further includes a ring inserted within an opening in the neck. The ring is crimp connected with the neck interior surface. The tank assembly still further includes a collar fitted over the neck exterior surface opposite said ring. The collar serves to place the neck in compression.

Description

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a Continuation-in-Part of currently-pending International Application Number PCT/US2004/017852 filed Jun. 4, 2004, which is a Continuation-in-Part of currently-pending U.S. patent application Ser. No. 10/454,222 filed Jun. 4, 2003. Priority is hereby claimed upon both of these applications under 35 U.S.C. § 365(c), and both applications are hereby incorporated by reference in their entireties.

BACKGROUND OF THE INVENTION

1. Field of the Invention
The field of the present invention is that of polymeric tank assemblies and more particularly, plastic fuel tank assemblies.
2. Discussion of the Related Art
In many plastic molded tanks, such as fuel tanks, instrument and fluid fitting attachments are typically made by a welding process (hot plate welding, ultrasonic welding or friction welding) or by inserting a ring or component into a molding tool and overmolding around it to create a mechanical bond for retention. These processes are difficult in that they require inserting components into a hot tool or require complicated secondary operations for maintaining good plastic welding integrity.
In some molded tanks, such as those molded by roto-molding processes, which are typically used for low volume tanks (marine applications, motor cycles, other recreational vehicles), the material used cannot be welded after the molding process due to material degradation with low density polyethylene. Further complicating the above-noted factors is that many polymeric materials have the tendency to creep (move over time) or distort when exposed to liquid hydrocarbons such as gasoline, diesel oil or other vehicle fuels.
It is desirable to provide a polymeric tank assembly having a more reliable method of attaching various parts, such as nozzles, drop-in fuel pumps, and level indicators.

SUMMARY OF THE INVENTION

A tank assembly is provided. A tank assembly in accordance with the present invention comprises a container having a neck portion and interior and exterior surfaces. The tank assembly further comprises a ring inserted within an opening in the neck wherein the ring is crimp connected with the neck interior surface. The tank assembly still further comprises a collar fitted over the neck exterior surface opposite the ring, thereby placing the neck in compression.
A method of providing a tank assembly is also provided.
Other features and advantages of the present invention will be further understood after reviewing the accompanying drawings and detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view of a tank assembly according to the present invention, with certain portions omitted for clarity of illustration.
FIG. 2 is an enlargement of a portion of the tank assembly shown in FIG. 1.
FIG. 3 is an enlargement of a portion of the tank assembly shown in FIG. 2.
FIG. 4 is a perspective view partially sectioned of an alternate preferred embodiment fuel tank assembly according to the present invention.
FIG. 5 is a sectional view of the fuel tank assembly shown in FIG. 4.
FIG. 6 is a perspective view of a bayonet-type fitting and locking ring utilizing the tank assembly shown in FIGS. 4-5.
FIG. 7 is a sectional view taken along lines 7-7 of FIG. 6.
FIG. 8 is a partial enlarged sectional view of a portion of FIG. 7.
FIG. 9 is another perspective view of the locking ring and inner ring utilized in the fuel tank assembly of FIGS. 4-5.
FIG. 10 is another alternate preferred embodiment of the present invention wherein a fluid connector is connected with a container of the tank assembly.
FIG. 11 is a schematic sectional view of an alternate preferred embodiment of the present invention illustrating the use of a clamping tool to crimp the collar of a fuel tank assembly with the neck and ring of the fuel tank assembly being removed for clarity of illustration.
FIG. 12 is an enlarged schematic view illustrating still another alternate preferred embodiment of the present invention, wherein a collar is crimped connected to a neck of a tank assembly by being rolled and, wherein an inner surface of the neck and a ring is supported during such rolling operation.
FIG. 13 is a schematic view of a collar used on an alternate preferred embodiment of the present invention, wherein an adjustable collar is provided.
FIG. 14 is an enlarged schematic view illustrating yet still another alternate preferred embodiment of the present invention, wherein a ring within a neck of a tank is crimp connected to the neck.
FIG. 15 is an enlarged schematic view illustrating yet still another alternate preferred embodiment of the present invention wherein a ring within a neck of a tank and a collar disposed about the outer surface of the neck have at least one protrusion protruding therefrom that penetrate the respective surface of the neck.
FIG. 16 is a block diagram illustrating a method of providing a tank assembly in accordance with the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Referring to FIGS. 1-3, a gas tank assembly 7 is provided. The gas tank assembly 7 has a polymeric tank 10. The polymeric tank 10 will typically be a plastic, such as low density or high density polyethylene or other suitable material. The plastic may be blow molded or roto-molded and typical thickness dimensions will be 5-6 mm.
The tank 10 has an integrally formed boss or neck 14. The neck 14 will typically have a thickness of 5-6 mm. The neck 14 has an interior surface 16 and an exterior surface 18. Positioned closely adjacent to or preferably press fitted within the interior surface 16 is a ring 20. The ring 20 has an outer surface 22. Projecting from the outer surface 22 are a series of protrusions or barbs 24. The barbs 24 penetrate into the neck interior surface 16. The barbs 24 help to insure that the ring 20 can meet a high pullout force requirement 363 kgf (800 lbf). The barbs also help to insure a level of sealing contact between the ring 20 and the neck interior surface 16 to hold an internal pressure of 351 gsc (5 psi) within the tank 10 and to also prevent permeation.
The ring 20 is typically fabricated from a metallic material. A sealing member 26 can be provided between the ring 20 and the neck interior surface 16. The sealing member may be a solid piece of material or a spray applied material. The sealing member can be Teflon® or other suitable material. Typically, a spray applied sealing member will be sprayed on the ring 20 before insertion into the neck 14. The ring may be generally straight along its surface adjacent the neck interior surface 16 or may have a slight angular groove indentation 28 for reception of the sealing member.
Fixably connected by brazing or welding, or manufactured integral to the ring 20 is a locking ring 30. The locking ring 30 has a series of geometrically spaced clamping arms 32. The clamping arms 32 have capture slots 34. The capture slots 34 have an angled opening 36.
Fitted over the neck exterior surface 18 is a collar 40. The collar 40 is typically sized to place the neck 14 in compression. The collar 40 may be an angular band which is press fitted over the neck exterior 18 or may be an adjustable clamping member which is tightened to place the neck 14 in compression. It is preferable that the ring 20 be more rigid than the collar 40.
The collar's compressive fitting is important for two reasons. First, some polymeric materials have a tendency to swell when exposed to certain hydrocarbon fluids. The tight fitting of the collar helps to overcome the swelling tendency. Second, the tight fitting of the collar 40 helps to ensure penetration of the barbs 24 into the polymeric material.
Referring to FIG. 1, the tank assembly 7 has an instrument, such as a fuel pump 44. The fuel pump 44 has an intake filter bag 46 connected thereto. The fuel pump is suspended by a post 48. The post 48 not only suspends the fuel pump within polymeric tank 10 but its interior also provides a conduit for wiring utilized to deliver power to the fuel pump which has a submersible motor.
The fuel pump 44 delivers fuel through a fuel line 50. The fuel line 50 and post 48 are connected with a module flange 51. The module flange 51 is pressed downward by a locking clamping ring 52. The clamping ring 52 has a cantilevered radially extending bayonet 54. The module flange has an angular groove 56 with an inserted sealing member or O-ring 58. Rotation of the clamping ring 52 causes the bayonet 54 to be inserted within the opening 36 of the capture slot and further rotation of the clamping ring causes the bayonet 54 to be slightly deformed and captured within the capture slot 34. The deformation of the bayonet 54 causes the clamping ring 52 to be urged downward, thereby clamping the module flange 51 into position. A similar arrangement as aforedescribed is provided for installation of a level sensor 64.
In another embodiment (not shown) the module flange can be manufactured integral with the clamping ring 52.
Referring to FIGS. 4-9, a tank assembly 70 is provided having a plastic fiber reinforced tank 72. The tank 72 has two openings with a neck 74. The neck 74 has an exterior surface 76 and an interior surface 78. A ring 80 is provided which is press fitted within the opening of the neck 74. The ring 80 is brazed or welded to a locking ring 82. The locking ring 82 can, if so desired, have an inner diameter that is press fitted upon a top portion 86 of the ring 80.
The locking ring 82 has a series of six geometrically spaced integrally connected clamping arms 84. The locking ring 82 also has an integrally joined retainer tab 88. The clamping arms 84 have slots similar to those aforedescribed in regards to the clamping arms 32.
Engaged by insertion and rotation thereof with the locking ring 82 is a locking clamping ring or plate 90. The clamping plate 90 is an annular member having a series of arcuate slots 92. The slots 92 are spaced to allow for their insertion over the clamping arms 84. The clamping plate 90 also has an inner diameter opening 94 which is flared generally conically upward. The clamping plate also has an annular ridge or mound 96.
To connect the clamping plate with the ring 80, the clamping plate is positioned to align the arcuate slots 92 with the clamping arms 84 and is dropped into position. After being dropped in position, the clamping plate 90 is torqued, bringing the mound 96 into engagement with the slots of the clamping arm 84, causing the mound 96 to be deformed downward and therefore clamped in position within the clamping arm slots.
The clamping plate also has a series of detent cutouts 100 and release cutouts 102. Upon rotation of the clamping plate 90, the retainer tabs 88 will typically be positioned within the cutouts 102. As the clamping plate 90 is further rotated, the retainer tabs 88 will engage with the ramps 104 of the release cutout until the retainer tab springs back into the detent cutout 100 preventing inadvertent releasing rotation of the clamping plate 90.
The clamping plate 90 clamps down on a module flange 106 by virtue of the interaction of the ridges with the slots in the locking arms 84. The module flange rests on the top portion 86 of the locking ring 80. The module flange 106 may have a sealant applied to its underside, or capture a sealing member (not shown) against locking ring 80. The force of the clamping plate 90 upon the module flange 106 may be sufficient to seal the module flange 106 with the locking ring 80. The module flange 106 is fixably connected with a post 110 which is connected with the fuel pump 112. A fuel line 114 fluidly connects the fuel pump 112 with the exterior of the tank assembly. The fuel line 114 is sealably connected with the module flange 106.
In similar fashion, electrical lines leading to the fuel pump 112 are fixably connected with the module flange 106 and a vent line 116 is connected with the insert plate 106 which delivers fumes to an emissions canister or to the vehicle emission control system.
In a manner similar to that previously described, the tank assembly 70 has a collar 120 which clamps to the exterior surface 78 of the neck 74.
FIG. 10 provides a fuel tank assembly 207. The fuel tank assembly 207 has a neck 214, a ring 220 and a collar 240 similar to those aforedescribed. The tank assembly 207 additionally has a fluid tube fitting 242 which is fixably connected with the ring 220. The tube fitting 242 has an exterior threaded surface 244 to threadably engage with interior threads 246 provided by a fluid conduit provided by a hose 248.
In other embodiments (not shown) the fitting 242 may have female rather than male threads and the hose threads may be male rather than female. The fitting 242 can also be other fluid fittings such as elbows, nozzles, or valve seats as required.
Referring to FIG. 11, a sectional portion of a collar 300 of an alternate preferred embodiment fuel tank assembly is shown. For clarity of illustration, the neck and ring are deleted from this view. The neck and ring of this embodiment of the fuel tank assembly can be fabricated according to the various embodiments previously described. The collar 300 is crimped connected to its encircled neck by being crimped by a clamping tool 302 which has a series of dies 304. Crimping the collar 300 allows the collar 300 to have a greater tolerance variation and still ensure a properly assembled part. Typically during the crimping operation, a backup tool similar to that as shown in FIG. 12, will be inserted to support the inner peripheral surfaces of the ring and neck during the crimping operation.
Referring to FIG. 12, an alternate preferred tank assembly 407 is provided. The tank assembly 407 has a neck 410, which can be fabricated in a manner as previously described from the prior embodiments. Additionally, when assembled, tank assembly 407 has a ring 412 that is inserted into an opening in neck 410, and a crimp connected collar 414 that is disposed about the exterior peripheral surface of neck 410 opposite ring 412. Collar 414 is crimp connected to the neck 410 by a roller 420 (as shown in FIG. 12), or by another crimping tool known in the art, such as, for example, a segmented jaw. During the rolling operation performed by roller 420, the interior peripheral surface of the neck 410 and the ring 412 are supported by a backup tool 422. As roller 420 rolls along the exterior peripheral surface of collar 414, a compression force is applied to collar 414 between roller 420 and backup tool 422, causing collar 414 to be crimped onto neck 410, thereby tightening the connection between neck 410 and ring 412. The portion of the exterior surface of collar 414 contacting roller 420 is deformed and pushed inward, causing an annular protrusion 415 to be formed on the interior surface of collar 414. Protrusion 415 penetrates and engages the exterior surface of neck 410, thereby creating a tight seal between collar 414, neck 410 and ring 412, as well as locking in and retaining ring 412 in the correct position within neck 410. It should be noted that while the embodiment described above includes a collar having one annular protrusion formed therein, collars having more than one protrusion remain within the spirit and scope of the present invention.
Referring to FIG. 13, a schematic top view of an adjustable collar 500 is shown. The collar 500 is especially suited for alternate preferred embodiments of the fuel tank assembly to be described later, wherein the ring is heat fusion connected with the neck.
Referring to FIG. 14, an alternate preferred embodiment tank assembly 507 is provided. The tank assembly 507 has a neck 510, which can be fabricated in a manner as previously described from the prior embodiments. Additionally, when assembled, tank assembly 507 has a ring 512 that is inserted into an opening in neck 510, and a collar 514 that is disposed about the exterior peripheral surface of neck 510 opposite ring 512. In this embodiment, ring 512 is crimp connected to neck 510 by a roller 520, or by any number of crimping tools known in the art. During the rolling operation performed by roller 520, the exterior peripheral surface of neck 510 and collar 514 are supported by a backup tool 522. As roller 520 rolls along the interior peripheral surface of ring 512, a compression force is applied to ring 512 between roller 520 and backup tool 522, causing ring 512 to be crimped onto neck 510. The portion of the interior surface of ring 512 contacting roller 520 is deformed and pushed outward, causing an annular protrusion 515 to be formed on the exterior peripheral surface of ring 512. Protrusion 515 penetrates and engages the interior surface of neck 510, thereby creating a tight seal between ring 512 and neck 510, as well as serving to lock in and retain ring 512 in the correct position within neck 510.
It should be noted that in another preferred embodiment, ring 512 and collar 514 are both crimp connected to the interior and exterior surfaces of neck 510, respectively. The crimp connection of collar 514 in this embodiment is as described above with respect to FIG. 12, and thus, will not be repeated. It should be further noted that while the embodiment described above includes a ring having one annular protrusion formed therein, rings having more than one protrusion remain within the spirit and scope of the present invention.
In either preferred embodiment, as neck 510 is exposed to hydrocarbons from the contents of the inner portion of the tank, it may swell. The combination of crimping ring 512 onto neck 510 and the placement and, in at least one embodiment, the crimping of collar 514 over the exterior surface of neck 510 opposite ring 512 provides the advantage of tightening the seal between ring 512 and neck 510. As neck 510 swells, collar 514 prevents the expansion of the swelling and ensures the penetration of the protrusions of the ring and/or collar into the respective interior and exterior surfaces of neck 510.
Referring to FIG. 15, still another alternate preferred embodiment tank assembly 607 is provided. Tank assembly 607 has a neck 610, which can be fabricated in a manner as previously described from the prior embodiments. Additionally, when assembled, tank assembly 607 includes a ring 612 that is inserted into an opening in neck 610, and a collar 614 that is disposed about the exterior peripheral surface of neck 610 opposite ring 612. In this embodiment, the outer peripheral surface of ring 612 has a first shape comprised of a pair of spaced apart protrusions 616 ₁, 616 ₂that are configured to penetrate and engage the interior surface of neck 610. The interior peripheral surface of collar 614 has a second shape that is both different from but complementary with, the first shape of ring 612, and that is comprised of a single protrusion 618 that is configured to penetrate the exterior surface of neck 610. Ring 612 and collar 614 are configured such that when ring 612 is inserted within neck 610 and collar 614 is placed over the combination of ring 612 and neck 610 such that ring 612 and collar 614 are in registry with each other, the respective protrusions are axially aligned with respect to axis 619 such that the centerline of protrusion 618 is located between protrusions 616 ₁and 616 ₂. When assembled, collar 614 is tightened causing a compression force to be applied between collar 614 and ring 612, and therefore, neck 610 The force causes the respective protrusions to penetrate the interior and exterior surfaces of neck 610, respectively, thereby sealing the connection of ring 612 and neck 610, and retaining ring 612 in the correct position within neck 610.
It should be noted that the above described embodiment providing for a ring having two protrusions and a collar having one is provided for exemplary purposes only. Accordingly, embodiments wherein the ring and collar have a greater or lesser number of protrusions remain within the spirit and scope of the present invention.
With continued reference with FIG. 15, in another preferred embodiment, the process described above with respect to FIGS. 12 and 14 can be performed to crimp collar 614 and/or ring 612 onto neck 610. Whether or not ring 612 and/or collar 614 are crimped onto neck 610, the combination of ring 612 and collar 614, and the protrusions thereof, create a tight seal between neck 610 and ring 612, in addition to locking in and retaining ring 612 in the correct position within neck 610. Additionally, as neck 610 is exposed to hydrocarbons from the contents of the inner portion of the tank, it may swell. The combination of crimping ring 612 onto neck 610 and the placement and, in at least one embodiment, the crimping of collar 614 over the exterior surface of neck 610 opposite ring 612 provides the advantage of tightening the seal between ring 612 and neck 610. As neck 610 swells, collar 614 prevents the expansion of the swelling and ensures the penetration of the protrusions of the ring and/or collar into the respective interior and exterior surfaces of neck 610.
It is desirable to make the various components of the fuel tank assembly as dimensionally tolerant as possible. Referring to the embodiments shown in FIGS. 1 through 15, the rings can be additionally fusion connected with the necks. The ring, or optionally the neck, or optionally both the ring and neck are heated to bring a surface temperature to a material dependent temperature (i.e., for high density polyethylene, between 121 and 204 degrees Celsius, or 250 and 400 degrees Fahrenheit) that will temporarily soften the material. The heating can occur by a hot air, induction heating or a radiant heating method. The heat fusion connection helps to properly engage and seal the ring with the interior surface of the plastic neck, especially when the neck opening surface finish is rough or if the opening of the neck is not completely round. Preferably, the ring is joined with the neck and the final step will be the application of the collar to the neck. This method of tank assembly fabrication and the product thereof are highly seated to utilizing an adjustable clamp 500 as shown in FIG. 13 or similar adjustable clamps.
With reference to FIG. 16, a method of providing a tank assembly is provided. The method in accordance with one preferred embodiment of the present invention includes the following steps. In a first step 700 a container having a neck portion and interior an exterior surfaces is provided. In a second step 702, a ring is inserted within an opening in the neck of the container. In a third step 704, a collar is fitted over the exterior surface of the neck, thereby placing the neck in compression. In a fourth step 706, the ring is crimp connected onto the interior surface of the neck, thereby creating a protrusion that penetrates and engages the interior surface of the neck. However, it should be noted that more than one protrusion may be created that penetrate and engage the interior surface of the neck.
In one alternate preferred embodiment, a fifth step 708 is performed in which the collar is crimp connected onto the exterior surface of the neck, thereby creating at least one protrusion that penetrates and engages the exterior surface of the neck. It should be noted that more than one protrusion may be created that penetrate and engage the exterior surface of the neck.
In another one alternate preferred embodiment, step 702 comprises inserting a ring within an opening in the neck wherein the ring comprises a pair of protrusions protruding from the exterior surface thereof that penetrate and engage the interior surface of the neck. In this one alternate preferred embodiment, step 704 comprises fitting a collar having a protrusion protruding from the interior surface thereof that penetrates and engages the exterior surface of the neck, thereby placing the neck in compression. The inventive method in accordance with this one preferred embodiment, as with those embodiments discussed above, also includes either one or both of steps 706, 708 such that either one or both of the ring and the collar are crimped connected onto the interior or exterior surface of the neck, respectively.
While preferred embodiments of the present invention have been disclosed, it is to be understood that they have been disclosed by way of example only and that various modifications can be made without departing from the spirit and scope of the invention as it is explained by the following claims.

Claims

1. A tank assembly, comprising:

a container having a neck portion and interior and exterior surfaces;

a ring inserted within an opening in said neck, said ring being crimp connected with said neck interior surface; and

a collar fitted over said neck exterior surface opposite said ring, thereby placing said neck in compression.

2. A tank assembly in accordance with claim 1 wherein said crimp connected ring includes at least one protrusion protruding from the exterior surface thereof, said at least one protrusion penetrating and engaging said interior surface of said neck to seal said connection between said ring and said neck and to retain said ring within said neck.

3. A tank assembly in accordance with claim 1 wherein said collar is crimp connected with said neck exterior surface.

4. A tank assembly in accordance with claim 3 wherein said crimp connected collar includes at least one protrusion protruding from the interior surface thereof, said at least one protrusion penetrating and engaging said exterior surface of said neck.

5. A tank assembly as described in claim 1, further including a sealing member between said ring and said neck interior surface.

6. A tank assembly as described in claim 1, having a fluid fitting fixably connected with said ring.

7. A tank assembly as described in claim 1, wherein said ring has a locking ring connected thereto, and wherein said locking ring has a clamping arm connected thereto.

8. A tank assembly as described in claim 7, wherein an instrument insert for said tank is connected with said tank by rotating a clamping plate which interlocks with said clamping arm.

9. A fuel tank assembly as described in claim 8, wherein said clamping plate clamps down on a module flange and wherein said instrument is connected with said module flange.

10. A tank assembly in accordance with claim 1 wherein said collar is adjustable.

11. A tank assembly, comprising:

a container having a neck portion and interior and exterior surfaces;

a ring inserted within an opening in said neck, said ring having at least one protrusion protruding from the exterior surface thereof, said at least one protrusion penetrating and engaging said interior surface of said neck creating a seal between said neck and said ring and retaining said ring within said neck; and

a collar fitted over said neck exterior surface opposite said ring, thereby placing said ring in compression, said collar having at least one protrusion protruding from the interior surface thereof, said at least one protrusion penetrating and engaging said exterior surface of said neck.

12. A tank assembly in accordance with claim 11 wherein said collar is adjustable.

13. A tank assembly in accordance with claim 11 wherein said ring includes a pair of spaced apart protrusions penetrating and engaging said interior surface of said neck.

14. A tank assembly in accordance with claim 11 wherein:

said ring includes a pair of spaced apart protrusions penetrating and engaging said interior surface of said neck; and

said collar includes one protrusion penetrating the exterior surface of said neck;

wherein when said ring and said collar are assembled with said tank assembly such that they are in register with each other, said protrusions of said ring and said protrusion of said collar are aligned such that said protrusion of said collar is located between said protrusions of said ring.

15. A tank assembly in accordance with claim 11 wherein said collar is crimp connected to said exterior surface of said neck.

16. A tank assembly in accordance with claim 11 wherein said ring is crimp connected to the interior surface of said neck.

17. A method of providing a tank assembly, comprising the steps of:

providing a container having a neck portion and interior and exterior surfaces;

inserting a ring within an opening of said neck;

fitting a collar over said neck exterior surface placing said neck in compression; and

crimping said ring onto said interior surface of said neck, thereby creating at least one protrusion protruding from the exterior surface of said ring, said at least one protrusion penetrating and engaging said interior surface of said neck.

18. A method of providing a tank assembly in accordance with claim 17 further comprising the step of adjusting said collar to increase the compression on said neck.

19. A method of providing a tank assembly in accordance with claim 17 further comprising the step of crimping said collar onto the exterior surface of said neck thereby creating at least one protrusion protruding from the interior surface of said collar, said at least one protrusion penetrating and engaging said exterior surface of said neck.

20. A method of providing a tank assembly, comprising the steps of:

providing a container having a neck portion and interior and exterior surfaces;

inserting within an opening of said neck, a ring comprised of at least one protrusion protruding from the exterior surface thereof, said at least one protrusion penetrating and engaging said interior surface; and

fitting a collar having at least one protrusion protruding from the interior surface thereof over said neck exterior surface such that said at least one protrusion penetrates and engages said neck exterior surface, thereby placing said neck in compression.

21. A method in accordance with claim 20 further comprising the step of adjusting said collar to increase the compression on said neck.

22. A method in accordance with claim 20 further comprising the step of crimping said ring onto said interior surface of said.

23. A method in accordance with claim 20 further comprising the step of crimping said collar onto said exterior surface of said neck.

24. A method in accordance with clam 20 further comprising the step of crimping both said ring and said collar onto said neck interior and exterior surfaces, respectively.