This application claims the benefit of U.S. Provisional Application No. 60/003,745, filed September 14, 1995. Eteld

The present invention pertains to flow line segments; more particularly the present invention pertains to lengths of pipe whose external surface is protected by a non-metallic collar.

Background

It is common practice to use pipes to either transport flowable fluids or to encase easily damaged items such as electrical cable. Oftentimes, several pipes are nested together or contained within a larger pipe. Nesting of pipes within a pipe to transport flowable fluids is particularly important when it is necessary to conduct a group of pipes under a riverbed as shown in Figure 1 or when one or more pipes must be heated to maintain the flow ofthe fluid contained therein.

It has been found that if one or more pipes are nested together in a larger pipe there is a possibility of damage to the smaller pipes if the smaller pipes are allowed to strike one another or the larger pipe. In extreme circumstances, a galvanic reaction may occur if pipes come into contact. Prior art attempts to separate pipes with non-metallic insulators have typically utilized expandable rubber bumpers as shown in Figure 2. An expandable rubber bumper is placed around a pipe by the use of a spreading mandrel. The spreading mandrel expands the rubber bumper so that it fits around the outer surface ofthe pipe. The positioning of several expandable rubber bumpers around a length of pipe requires sliding the expandable rubber bumpers and the spreading mandrels all along the pipe until the desired location for the expandable rubber bumper is reached. Such method of protecting pipes with expandable bumpers is both time consuming and expensive.

There is therefore a need in the art to provide a simple, efficient way of placing non- metallic collars around the external surface of pipes. Summary

The present invention provides a simple efficient way of placing a non-metallic insulating collar around the external surface ofa length of pipe. The non-metallic pipe collar ofthe present invention includes multiple arcuate sections which are mechanically interconnected one to

another with a non-metallic fastener. Such interconnection does not extend beyond the outer surface ofthe pipe collar.

In a first embodiment of the invention the arcuate sections are hingedly attached one to another. In another embodiment of the invention tapered shims are placed around the outer surface of the pipe. Following the placement ofthe tapered shims around the outer surface of the pipe an outer collar having a tapered inner surface is placed around the shims. The interference fit between the tapered outer surface ofthe shims and the tapered inner surface of the outer collar provides a tight connection of the collar to the pipe. For an even tighter connection it has been found that both ofthe tapered surfaces may be roughened. Roughening the surfaces enhances the effect ofthe interference fit between the tapered surfaces. It has also been found that the outer surface ofthe pipe may be protected by placing an elastomeric liner against the inside surfaces ofthe pipe collar or shims which contact the external surface ofthe pipe.

Brief Description of he Drawing Figures A better understanding ofthe non-metallic pipe collar ofthe present invention may be had by reference to the drawings wherein:

Figure 1 is a cross-sectional view ofa river illustrating the passage ofa pipe underneath the riverbed;

Figure 2 is a perspective view ofa flow line within a pipe including a prior art expandable bumper;

Figure 3 is a perspective view of the non-metallic pipe collar of the present invention installed on a pipe placed within an outer pipe where the outer pipe is shown in partial section;

Figure 3 A is a front elevational view ofthe non-metallic pipe collar shown in Figure 3;

Figure 4 is a perspective view ofa non-metallic hinged pipe collar in its open position for installation on or removal from a flow line segment;

Figure 5 is a front elevational view similar to Figure 3 A with a portion ofthe pipe collar cut away to show installation ofthe non-metallic fastener;

Figure 6 illustrates the relationship of the non-metallic pipe collar to the flow line segment shown in Figure 4 only in left side elevation; Figure 7 is a left side elevational view similar to Figure 6 with the addition of the spreader tools used to move the upper and lower sections ofthe non-metallic pipe collar to their open position;

Figure 8 is a perspective view of a first alternate embodiment ofthe non-metallic pipe collar of the present invention where the non-metallic fasteners are placed tangentially to the pipe;

Figure 9 is a perspective view similar to Figure 8 illustrating the use ofa closing tool to bring the ends of the non-metallic pipe collar together before the non-metallic fasteners are installed;

Figure 10 is a perspective view ofa second alternate embodiment similar to embodiment shown in Figure 8 but with the addition of internal shim pieces;

Figure 1 1 is a perspective view of a third alternate embodiment wherein an elastomeric liner is placed between the non-metallic pipe collar and the external surface of the flow line segment;

Figure 12 is a perspective view similar to Figure 1 1 showing the placement ofthe collar on the flow line segment before the installation of the non-metallic fasteners;

Figure 13 is a perspective view ofa single piece collar on a flow line segment just before being slid over the non-metallic shim segments;

Figure 14 is a cross sectional view ofa non-metallic shim segment showing the taper on the extemal surface;

Figure 15 is a perspective view showing a single piece non-metallic collar installed over the non-metallic shim segments; Figure 16 is a perspective view showing multiple non-metallic pipe collars installed on a heated flow line segment;

Figure 17 is a cross sectional view taken at line 17-17 of Figure 16. Description of the Embodiments

In environments where it is necessary to rest pipes or to pass one or more pipes within a larger pipe, separation of the pipes one from another or from the larger pipe is not only desirable but required by some construction codes. One example of a pipe within a pipe environment is shown in Figure 1 where a large pipe P passes through the soil S underneath a river R to allow flow lines or pipes to traverse the distance between the right bank RB ofthe river R to the left bank LB ofthe river R. In Figure 2 a large pipe P such as the one shown in Figure 1 is shown partially cut away.

Therein a flow line FL is shown within the pipe P. Also shown is a prior art bumper B. Such prior art bumpers B are made of an elastomeric material such as rubber. The bumper B is installed on the flow line FL by using a spreader mandrel. The spreader mandrel and the bumper

B are moved along the pipe until the bumper B is at the desired location on the external surface ES ofthe flow line FL.

As shown in Figure 3, the non-metallic pipe collar 10 of the present invention is designed for use in the same environment as the bumper B illustrated in Figure 2. Specifically, when installed, the non-metallic pipe collar 10 of the present invention goes around a flow line FL which passes within a larger pipe P. However, as will be seen in the description which follows, the installation ofthe non-metallic pipe collar 10 of the present invention on a flow line FL is significantly easier.

In Figures 3 and 3 A it may be seen that the preferred embodiment ofthe non-metallic pipe collar 10 ofthe present invention includes a stepped split 12. The use of a stepped split 12 allows a threaded non-metallic fastener 14 to pass through a non-threaded hole portion 16 and engage a threaded hole portion 18. Thus when the threaded non-metallic fastener 14 is engaged with the non-metallic pipe collar 10 it is oriented substantially parallel to the axis ofthe flow line FL. In Figure 4 the installation of the non-metallic pipe collar 10 on the flow line FL is shown. By using a hinge or weakened section 20 formed diametrically opposite the stepped split 12 the upper portion 22 ofthe non-metallic pipe collar 10 may be moved away from the lower portion 24 ofthe non-metallic pipe collar 10. When the upper portion 22 ofthe non-metallic pipe collar 10 is moved away from the lower portion 24 ofthe non-metallic pipe collar 10 an opening 26 is formed at stepped split 12. This opening 26 allows the flow line FL to be placed within the interior portion 28 ofthe non-metallic pipe collar 10.

When the flow line FL is within the interior portion 28 ofthe non-metallic pipe collar 10 the upper portion 22 ofthe non-metallic pipe collar 10 is brought back together with the lower portion 24 ofthe non-metallic pipe collar 10 thus closing opening 26. The non-metallic fastener 14 is then threaded through the unthreaded portion hole portion 16 and into the threaded hole portion 18. The non-metallic fastener 14 is turned sufficiently to secure the non-metallic pipe collar 10 to the external surface ES ofthe flow line FL. While only one non-metallic fastener 14 is show in the preferred embodiment, it will be understood that multiple non-metallic fasteners may be used without departing from the scope ofthe invention. As may be shown in Figure 5, no portion ofthe non-metallic fastener 14 extends beyond the outer surface of the non-metallic pipe collar 10 when the non-metallic pipe collar 10 is installed on the flow line FL. When a non-metallic fastener 14 with an enlarged head 15 such as the one shown in the preferred embodiment is used it is necessary to provide an enlarged

portion 17 in the unthreaded hole segment 16 to accommodate the enlarged head 15 which allows all ofthe non-metallic fastener 14 to be within the pipe collar 10.

A better view ofthe hinged or weakened section 20 is shown in Figure 6. Therein it may be seen that the hinged or weakened section 20 is a notch formed in the body ofthe non-metallic pipe collar 10. By causing the opening 26 to be formed diametrically opposite the stepped split

12 the notch at the hinged or weakened section 20 closes as the non-metallic pipe collar 10 is opened. As previously indicated the flow line FL is placed into the interior 28 of the non- metallic pipe collar 10 by placing the non-metallic pipe collar 10 around the flow line FL.

To facilitate the creation of the opening 26 between the upper portion 22 of the non- metallic pipe collar 10 and the lower portion 24 ofthe non-metallic pipe collar 10 two spreader tools 30 and 32 are used. One end 30a ofthe first spreader tool is placed in a hole 23 formed in the upper portion 22 ofthe non-metallic pipe collar 10. A fulcrum portion 30b of the spreader tool 30 is placed against the outer surface 1 1 of the non-metallic pipe collar 10. The same is done for the other spreader tool 32. Specifically one end 32a ofthe second spreader tool 32 is placed in a hole 25 in the lower portion 24 of the non-metallic pipe collar 10 and the fulcrum portion 32b ofthe spreader tool 32 is placed against the outer surface 11 ofthe non-metallic pipe collar 10. By placing an inward force, as shown by arrows A and B, on a second end 30c and 32c ofthe two spreader tools 30 and 32 respectively, the stepped split 12 ofthe non-metallic pipe collar 10 is pulled apart thus forming opening 26. It is now possible to install the non-metallic pipe collar 10 around a flow line FL from the side ofthe flow line FL.

It will be understood by those of ordinary skill in the art that while a single step is shown in stepped split 12 it is also possible to form the same type of connection using one or more steps or tongue and groove connections between the upper portion 22 ofthe non-metallic pipe collar 10 and the lower portion 24 ofthe non-metallic pipe collar 10. It will also be understood by those of ordinary skill in the art that while one hinge or weakened section 20 is shown in the preferred embodiment, multiple hinge or weakened sections may by used without departing from the scope ofthe invention.

It will be still further understood by those of ordinary skill in the art that more than one split step may be used if the non-metallic pipe collar 10 is formed of multiple arcuate segments; such construction will be understood by following the description of Figure 11 below.

A first alternate embodiment ofthe non-metallic pipe collar 110 of the present invention is shown in Figure 8. Parts having a similar construction and orientation to the parts shown in the preferred embodiment are identified by the same reference number but for the " 1 " which

appears in the hundreds place. In the first alternate embodiment the non-metallic fasteners 1 14a and 1 14b are oriented in a direction tangential to the flow line FL. Thus, instead of using a stepped split 12 as shown in the preferred embodiment, a flat split 113 is used between the upper portion 122 and the lower portion 124 of the non-metallic pipe collar 1 10. While two non- metallic fasteners 114a and 114b are shown it will be understood by those of ordinary skill in the art that any number of non-metallic fasteners may be used. Note that, as in the preferred embodiment, two holes 123 and 125 appear for eventual engagement by spreading tools.

As the non-metallic collars become larger when used with larger and larger flow lines or less flexible when more rigid non-metallic materials are used, it may be necessary to use a closing tool 140 to bring the upper portion 122 ofthe non-metallic pipe collar 110 together with the lower portion 124 ofthe non-metallic pipe collar 1 10 at the flat split 1 13. The closing tool 140 has finger portions 140a and 140b which may be inserted into holes 123 and 125. When the handles ofthe closing tool 140 are squeezed together, the non-metallic pipe collar 1 10 is ready for the insertion of one or more non-metallic fasteners 1 14 to secure it in place on the external surface ES ofthe flow line FL.

Yet another embodiment ofthe non-metallic pipe collar 210 ofthe present invention is shown in Figure 10. In Figure 10 the same reference numbers are used to identify parts having a similar function and location to those parts shown in the preferred embodiment but for the use ofa "2" in the hundreds place. While most ofthe embodiment depicted in Figure 10 is the same as shown in Figures 8 and 9 there are two differences. First, instead of threading the threaded non-metallic fastener 214 into a threaded hole foimed within the pipe collar 210, a non-metallic nut 219 is used. Accordingly, the size ofthe holes formed in the non-metallic pipe collar 210 are ofa sufficient size to accommodate the enlarged head portion 215 ofthe non-metallic fastener 214 and the non-metallic nut 219. Particular attention should be given to the non-metallic semicircular shim segment 250.

The non-metallic shim segment 250 is placed on the external surface ofthe flow line FL before the non-metallic pipe collar 210 is placed around the flow line FL. While the first of two semicircular non-metallic shim segments 250 is shown in Figure 10 is will be understood by those of ordinary skill in the art that any number of non-metallic shim segments 250 may be used as long as all the non-metallic shim segments 250 encircle the flow line FL before the non- metallic pipe collar 210 is placed around the flow line FL. It has been found that when a plurality of non-metallic shim segments 250 are used better results can be obtained if the exterior surface 252 ofthe non-metallic shim segment 250 and the interior surface 229 ofthe non-metallic

pipe collar 210 are roughened. Such roughening can be accomplished by any number of methods to include forming screw threads on the exterior surface 252 ofthe non-metallic shim segment 250 and the interior surface 229 ofthe non-metallic pipe collar 210.

Yet another embodiment ofthe non-metallic pipe collar 310 ofthe present invention built on the embodiment shown in Figures 8 and 9 is shown in Figure 1 1. In this embodiment those parts having a similar location and function to those shown in the preferred embodiment are identified by the same reference number but for a "3" in the hundreds place. While the hinge or weakened portion has been eliminated from the integral non-metallic pipe collar in favor of two separable portions 322 and 324 which come together at two flat splits 313a and 313b, it will be understood by those of ordinary skill in the art that each ofthe two separable portions 322 and

324 could include a hinge or weakened portion without departing from the scope of the invention. It will also be understood by those of ordinary skill in the art that while two separable portions 322 and 324 are shown in Figure 1 1, any number of separable portions may be used without departing from the scope ofthe invention. In some circumstances, there may be a brittle coating on the flow line FL or it may be necessary to protect the surface integrity ofthe extemal surface ES ofthe flow line FL. In such a situation, the use ofa liner 360 or 362 within the non-metallic pipe collar 310 may be required. Such liners may be full such as the liner 360 which is the width ofthe non-metallic pipe collar 310 and may also include ears 364 to extend into the flat split 313. Altematively the liner 362 may be smaller and fit within the center portion ofthe non-metallic pipe collar 310. Such liners are typically formed of an elastomeric material.

When multiple separable portions such as 322 and 324 shown in Figure 11 are used, it may be necessary to use more than one closing tool 340 to install the non-metallic pipe collar 310 on a flow line FL as shown in Figure 12. In Figure 13 is shown yet another embodiment of the non-metallic pipe collar 410 of the present invention. This embodiment is a variation ofthe embodiment shown in Figure 10 which includes non-metallic shim segments 250. Those parts having similar location and construction to those in the preferred embodiment are given the same reference numbers but for the inclusion ofa "4" in the hundreds place. In this embodiment, two or more non-metallic shim segments 450 are placed on the extemal surface ES ofthe flow line FL. A singular, substantially circular non- metallic pipe collar 410 is used to ride over the non-metallic shim segments 450. Because the diameter of the interior 428 of the non-metallic pipe collar 410 is greater than the extemal diameter of the flow line FL it is easy to slide the non-metallic pipe collar 410 to the pre-

determined location on the flow line FL where the non-metallic shim segments 450 have been placed.

It has been found that by forming each non-metallic shim segment 450 with a tapered external surface 454 as shown in Figure 14 and forming the interior 429 ofthe non-metallic pipe collar 410 with a tapered surface the interference fit between the non-metallic pipe collar 410 and the ring of non-metallic shim segments 450 will lock the non-metallic pipe collar 410 firmly on the extemal surface ES of the flow line FL. As previously indicated, roughening the outer surface ofthe non-metallic shim segment 450 and the interior suiface 429 ofthe non-metallic pipe collar 410 enhances the locking ofthe non-metallic pipe collar 410 to the extemal surface ES of the flow line FL. In actual practice it has been shown that a taper of about 3 ° is satisfactory. This is shown by the symbol α in Figure 14.

Actual assembly ofthe embodiment described in Figures 13 and 14 is shown in Figure 15. Therein a compression tool assembly 470 is shown. A distal portion 472 ofthe compression tool assembly is placed at the far edge 458 ofthe ring of non-metallic shim segments 450. A proximal portion 474 ofthe compression tool assembly 470 is placed at the near edge 408 ofthe non-metallic pipe collar 410. Compressive force such as that exerted by a hydraulic cylinder 476 is used to bring the two portions 472 and 474 ofthe compression tool assembly 410 together. This will cause the inner surface 429 ofthe non-metallic pipe collar 410 to slide over the exterior surface 452 of the ring of non-metallic shim segments 450 thus locking the non-metallic pipe collar 410 to the exte al surface ES of the flow line FL.

In Figure 16 multiple non-metallic pipe collars 10 are shown on a single flow line FL. Such configuration has been used particularly where the fluid in the flow line FL must be kept warm to be able to flow. This is especially critical when the pipe P is placed in a cold environment such as sea water. In such installations, the flow line may be surrounded by insulation (not shown) or the assembly may include a heating element such as a wire W carrying electrical energy. In such installations, it has been found that it may be necessary to form the non-metallic pipe collars from a non-charring plastic. The heating element W will be placed in the space between the outside ofthe non-metallic collar 10 in the inside ofthe pipe P as shown in Figure 17. While the present invention has been described by reference to both the preferred and alternate embodiments, it will be understood by those of ordinary skill in the art that numerous other embodiments of the instant invention are possible. Such numerous other embodiments shall fall within the scope and meaning ofthe appended claims.