Abstract:
A novel multiple configuration hand assembly centralizer system adaptable to virtually all known rock and soil anchoring applications is presented. The primary components to the centralizer include a plurality of straps and two collars which hold the straps in place utilizing a unique locking mechanism. Most preferably the standardized parts will be made from a petroleum based material. The straps are easily and manually inserted into slots in each of the collars. Each collar may be molded to provide slots for three or more straps. The collars are molded with grout passages between slots thereby allowing more than the required amount of grout to be fed through the centralizer. On a multiple configuration centralizer system, a housing assembly and retainer clip are used to frictionally hold the straps at user defined intervals on a standard zip tie. The flexibility and compressibility of the strap finger ends allows for adaptability of the centralizer device to various diameter elongated objects, such as rebar and corrugated pipe, to be centrally positioned. In addition, the centralizer system components and varying size of the straps permits easy manual assembly, on-site without the use of conventional tools, for numerous applications.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates generally to centralizer devices used in rock and soil anchoring applications in the construction industry. More particularly, the present invention relates to a novel centralizer device capable of multiple configurations, and capable of manual assembly from component parts, on-site at application construction sites, said assembly requiring no tools. 
     2. Description of the Related Art 
     Centralizers are devices used to provide space between an anchorage and the walls of an anchor bore hole, thereby allowing grout to be injected into the bore hole for securing of the anchorage. The centralizer field includes many different inventions which have attempted to improve the functions of the centralizer. Its two primary functions are to: 1) provide space between the anchorage and the walls of the bore hole, and 2) to provide a locking mechanism for the several centralizer elements so that they do not fail once installed in the ground. 
     More specifically, known relevant prior art has focused on improving the locking mechanism. Unfortunately, patented inventions in this field still exhibit many problems and disadvantages which the present invention has overcome. Even though previous designs have had some success in overcoming past problems, remaining problems include inflexibility in meeting multiple applications, relatively complex locking mechanisms, and using heavy materials such as steel. In addition, known prior art virtually neglects the problem of optimizing the space between the anchorage and the bore hole walls for each application. As is well known in the art, grout is used to secure the anchorage in a bore hole. The more secure the anchorage, the safer the entire anchor, thereby minimizing the possibility of a failure of a dam, a transmission tower, or an oil well, or other anchor applications. 
     Therefore, it is clear that a need exists for an improved centralizer device that is capable of multiple configurations, capable of being assembled on site, manually requiring no tools, from uniform components, provides an effective mechanism for grout flow, allows use in multiple applications, is light weight, strong, and is even more cost effective to manufacture and ship than existing centralizers. The present invention overcomes these and many other long-standing and even ignored problems and disadvantages of the prior art. 
     Some of the related prior art includes the following U.S. Patents: Wills, et al. U.S. Pat. No. 4,042,022; Ferstay U.S. Pat. No. 4,866,903; Chickini, Jr. et al. U.S. Pat. No. 4,247,225; Dane U.S. Pat. No. 4,077,470; Wilson U.S. Pat. No. 4,269,269; Spikes U.S. Pat. No. 4,651,823; Patterson et al. U.S. Pat. No. 4,909,322; Svenson U.S. Pat. No. 4,520,869; and Kraft U.S. Pat. No. 4,143,713. 
     Wills, et al. (U.S. Pat. No. 4,042,022) discloses a centralizer device with a plurality of blades received in slots by a pair of cylindrical collars. This invention is directed towards preventing the separation of parts during use. Disadvantages to this design include the lack of flexibility in the blade material, a design directed to a specific dimension envelope for the centralizer, and an assembly requiring hammers to insert the steel blades, and therefore requiring a lengthy assembly time. 
     Ferstay (U.S. Pat. No. 4,866,903) discloses a one piece centering device for thread bars. The device has holes to allow grout to pass around or through the device. Disadvantages to this device include restricted applications because of its small size, and lack of an expanding feature to fit different size bore holes. The device seems directed to use only in building applications. Another disadvantage is the small size of the holes in the device to allow grout to pass. It appears that it would be difficult for grout to pass through the small holes in sufficient quantities to provide sufficient force transfer to the ground for a safe anchor. Still another disadvantage is the use with threaded bar. Installing the device takes more time than would an non-threaded device. 
     Chickini, Jr. et al. (U.S. Pat. No. 4,247,225) discloses an alignment device comprising a single component for mounting an anchor cable in an elongated cable hole in a guy line anchoring environment. One disadvantage with this device is the fixed diameter of the collar for passing cable through. Another disadvantage is the small diameter of the collar for passing any cable through. Still another disadvantage is the somewhat complex locking mechanism to prevent the device from coming apart. 
     Dane (U.S. Pat. No. 4,077,470) discloses a well centralizer directed to an improved means to connect bow elements to collars. Disadvantages to this device include a complex connecting apparatus, limited applicability in that it is for use only in oil well casings, use of relatively heavy steel for material, and also a need to bend the locking tab to allow for locking the bow elements into the collars. 
     Wilson (U.S. Pat. No. 4,269,269) discloses a deformable tab on collars as a means to prevent each spring from disengaging from the end collars when the centralizer is subjected to compressional loading. One disadvantage to this device includes limited applicability in that use is only directed to oil, gas, or water drilling situations. Another disadvantage is that the deformable tab does not appear to be of a robust design, therefore the tab is likely to break. Still another disadvantage is that numerous conventional tools, including hammers, vises and pipe wrenches are needed for assembly. Yet another disadvantage is the metal material used requiring forging. The metal material, being relatively heavy compared to plastic, requires more costs for manufacture, crating and shipping. 
     Spikes (U.S. Pat. No. 4,651,823) discloses a well bore centralizer directed to an improved connectible means between the bowed elements and the collars. Disadvantages include a complex collar locking design, bow elements set to a specific arcuate position, and the hammer force required for assembly. Still another disadvantage is the use of metal in the design, thereby requiring more costs for manufacturing, crating and shipping. 
     Patterson et al. (U.S. Pat. No. 4,909,322) disclose a casing centralizer with bendable tab to allow a more improved locking mechanism to secure the bow springs in the collars. Disadvantages to this device are similar to others listed in previously mentioned prior art. One disadvantage is the inability of the device to be flexible thereby limiting its applicability to only certain sizes of bore holes. Another disadvantage is the use of metal which increases costs for manufacture, crating and shipping. Yet another disadvantage mentioned in some of the other prior art is the need to bend the metal before the bow springs can be inserted into the collars. Bending the metal can create a point for failure after installation. 
     Svenson (U.S. Pat. No. 4,520,869) discloses a centralizer for a well casing directed specifically to a third channel of the collar compressible at final assembly allowing for locking of the bow and collar together. Disadvantages in using this device include the complex locking mechanism, limited use to well casings, use of metal requiring more costs, and a need to use hammering tools before assembly can be completed. 
     Kraft (U.S. Pat. No. 4,143,713) discloses a self-centering basket for use in mining or oil fields. More specifically, the device is directed towards lugs to hold down steel bars to prevent the bars from jumping out of engagement. Disadvantages include the use of steel, thereby increasing manufacturing and shipping costs. Because the design is meant to be locked upon assembly, no means are provided for mistakes in assembly. It would appear to be virtually impossible to disassemble to correct mistakes. In addition, no means are disclosed for altering the outer dimensions of the device should the on site diameter of the bore hole be greater or less than expected. 
     In summary, all the cited patents have a multitude of disadvantages. As is quickly realized, most of the patents disclose similar attempts to solve one problem with previous centralizer designs. Most are directed to improving centralizer locking techniques. However, problems still exist with attempts to improve centralizer locking techniques. Therefore, it would be highly desirable to solve the locking problem with an elegant, simple, inexpensive centralizer design. In addition, it would be highly desirable to solve other problems in the field of centralizer devices that have been virtually ignored. Therefore, it is an object of the present invention to provide a multiple configuration capable centralizer device allowing hand assembly in the field at construction sites or other sites requiring centralizer applications. Also, the unique features of the present invention allow for its use in virtually any anchoring application situation. It is a further object of the present invention to use a non-metal material, thereby reducing costs throughout the manufacturing to end use process and eliminating the need for any use of conventional tools for assembly. Another object of the invention is to provide numerous interchangeable components for custom orders and multiple embodiments for optimized use in the field, such components allowing for rapid and simple hand assembly requiring no tools, on site, in customer required specifications. 
     SUMMARY OF THE INVENTION 
     Therefore, the principal object of the present invention is to provide a new and improved centralizer device that is capable of multiple configurations. 
     It is a further object of the present invention to provide such a new and improved centralizer device that is capable of being assembled on site, manually by hand using no tools, from standardized components. 
     It is yet a further object of the present invention to provide such a new and improved centralizer device that provides an effective mechanism for grout flow. 
     It is yet another object of the present invention to provide such a new and improved centralizer device that allows use in multiple applications and is light weight, yet strong. The rigid straps include a central portion semi-circular tapered riser which widens at its peak, and which radius determines the size of rigid strap to use in a given bore hole application, whereby said tapered riser which broadens in the center adds strength to said rigid strap member, and allows for less difficulty in inserting said centralizer system into said bore hole due to increased surface area. 
     It is yet another object of the present invention to provide such a new and improved centralizer device that is even more cost effective to manufacture and ship to application job sites than existing centralizers. 
     Briefly, the above and further objects of the present invention are realized by providing a new and improved centralizer device that provides for usage of a number of standardized parts, namely, collars and straps, which may be quickly assembled on-site in the field without the use of tools. These parts are interchangeable to allow for custom configuration of the centralizer device in the field as the circumstances dictate the application requirements. 
     The parts for the present invention include straps constructed to include three or more separate flexible finger portions, when fully assembled. These flexible finger portions flex toward and snugly fit onto an elongated object to be centrally positioned in a bore hole, and the finger portions allow for the centralizer to be mounted using tie wire or zip tie in grooves on each distal end. This permits the centralizer to be immobilized in position around the object to be centrally positioned in a bore hole. In addition, the collar locking mechanisms located on the straps allows for ease of assembly on location without the use of conventional tools. 
     The rigid straps include a central portion semi-circular tapered riser which widens at its peak. The radius of the riser determines the size of rigid strap to use in a given bore hole application. The tapered riser which broadens in the center adds strength to the strap and allows for less difficulty in inserting the centralizer system into the bore hole due to increased surface area. The straps include a centrally located gusset on one side, positioned within the curved inner portion to provide strength and reinforcement to the straps. 
     The straps also include one or more compression tabs on each end for enhanced attachment to an earth anchor rebar, a corrugated pipe or cable strands. The compression tabs are radially cut to provide a tighter conformed attachment to rounded earth anchor mechanisms. In this way, the compression tabs apply direct pressure opposite the tie wire to ensure centralizer movement or slippage is prevented. The rigid strap end consists of flexible fingers which can be compressed to conform to any diameter and can be wired snugly to an object to be centrally positioned. 
     Another standardized part for the novel centralizer device are two generally cylindrical collars having three or more strap slots which accept the flexible end finger portions of the straps. The individual straps are inserted into each collar manually. Once all straps are inserted in both collars, the centralizer is assembled manually by pushing from both ends, then locked with a unique locking tab mechanism. Therefore, the centralizer can be manually assembled when needed for any given application, and no separate conventional tools are required for centralizer assembly. 
     While most collars are solid and uniform, having no break or slit, some collars may include one slit to allow for the rapid mounting of the assembled centralizer system onto an elongated object without the need to slide the centralizer system down the length of the elongated object to be centrally positioned in the bore hole. In addition, the collars are constructed so as to provide areas for grout channels between the strap insets. 
     In a multiple configuration centralizer, a retainer housing having a single slot is used in place of the standardized collars. Each of the straps are manually insertable into the retainer housing slot and locked into place by a locking ramp. A tie retainer clip having a plurality of clip fastening tines each having a raised portion is inserted into the retainer housing slot and is locked into place. The raised portion of the tines locks into the locking ramps within the multiply grooved portion of the strap. 
     The retainer clip is capable of accepting a zip tie so that the novel multiple configuration centralizer is formed around an elongated object by threading a zip tie through each strap slot formed by the connection of the strap housing and the tie retainer clip. The resulting slot is sized so as to hold the zip tie very snugly, preventing undesired movement when mounting the assembled centralizer system onto an elongated object to be centrally positioned. 
     The unique locking mechanism includes a locking ramp positioned on an inside surface of the strap when the strap is inserted into the collar slot or the retainer housing slot. The locking ramp prevents movement of the collar along the strap. The straps are constructed with a portion that has a multiple grooves with each groove having a locking tab. 
     All standardized parts of the novel multiple configuration centralizer are constructed of a thermoplastic material including polypropylene and polyethylene which is easily moldable, provides strength, durability and economy of manufacturing. 
     The multi-configuration rigid strap centralizer system composed of a plurality of strap housings are fitted with a tie retainer clip and are economically shipped to, and provided on-site in a ladder-like configuration with two zip ties snugly connecting the straps. 
     Because of the molding process and the materials used for construction of the novel centralizers, costs for manufacturing, crating, and shipping are greatly reduced from the prior art devices. These, and other features and advantages of the present invention are set forth more completely in the accompanying drawings and the following detailed description of the drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The above mentioned and other objects and features of this invention and the manner of attaining them will become apparent, and the invention itself will be best understood by reference to the following description of the embodiment of the invention in conjunction with the accompanying drawings, wherein: 
     FIG. 1 is a perspective view of a centralizer in the prior art, illustrating a blades and collar construction; 
     FIG. 2 is a perspective view of a typical PVC pipe derived centralizer as is currently constructed by convention, in place on a reinforcement bar (hereinafter “rebar”) with a grout tube; 
     FIG. 3 is a front elevational view of an assembled centralizer illustrating the straps and collars, constructed in accordance with the present invention; 
     FIG. 4 is a front perspective view of the present centralizer invention illustrating the assembled straps and collars, yet rotated slightly from the view of FIG. 3; 
     FIG. 5 is a back perspective view illustrating the strap in greater detail; 
     FIG. 6 is a front perspective view illustrating the strap in greater detail; 
     FIG. 7 is a side elevational view illustrating the strap in greater detail; 
     FIG. 8 is an enlarged plan view illustrating the strap in greater detail; 
     FIG. 9 is an enlarged perspective view of one embodiment of a typical collar illustrating three slots for straps and other details; 
     FIG. 10 is an enlarged perspective view of a second embodiment of a typical collar illustrating four slots for straps; 
     FIG. 11 is an enlarged perspective view of a third embodiment of a typical collar illustrating five slots for straps; 
     FIG. 12 is an enlarged perspective view of a fourth embodiment of a typical collar illustrating six slots for straps; 
     FIG. 13 is a front elevational perspective view of straps and collars assembled to form the finished centralizer, constructed in accordance with the present invention; 
     FIG. 14 is a perspective view of the bottom of the retainer clip; 
     FIG. 15 is a perspective view of the top of a strap housing; 
     FIG. 16 is a partially cut-away side view of a portion of a strap housing/tie retainer clip assembly, illustrating the locking tab mechanism constructed in accordance with the present invention; 
     FIG. 17 is a perspective top view of the strap housing/tie retainer clip assembly with zip tie and tie wires in place, constructed in accordance with the present invention; 
     FIG. 18 is a side view of a multiple strap centralizer assembly as it might appear when securely mounted on a corrugated pipe using zip ties and tie wires; 
     FIG. 19 is a plan view of a 4-strap centralizer assembly as it might appear when securely mounted on a corrugated pipe using zip ties and tie wires; 
     FIG. 20 is a plan view of an  8- strap centralizer assembly as it might appear when securely mounted on a corrugated pipe using zip ties and tie wires; and 
     FIG. 21 is a side elevational view of a 6-strap multiple configuration centralizer ladder-like assembly as it might appear when shipped, or prior to mounting on-site. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring initially to FIG. 1, a perspective view of an invention of the prior art is shown. A centralizer  1  is shown comprised of a plurality of straps  2  and two collars  3 . This prior art (Spikes, U.S. Pat. No. 4,651,823) is generally representative of many of the cited prior art patents in the Background section above. The collars  3  show a complex metal hinged locking mechanism. The metal straps  2  are set to a specific arcuate position. The present invention makes novel improvements upon this prior art and those devices of the other patents cited. 
     Referring now to FIG. 2, another prior art centralizer device  5  is shown here. This centralizer device  5  is derived from schedule 40 PVC pipe. During construction the PVC pipe is split and stretched apart to form the spacer members  6 . It is shown in place on a “rebar”, cable or strand  7  and having a grout tube  8  attached thereon. 
     Turning to FIG. 3, there is shown a front elevational view of an embodiment of the novel centralizer device  10  constructed in accordance with the present invention. This centralizer  10  is composed of two collars  12  and  14  which hold in place a plurality of flexible strap fingers as exemplified by flexible strap fingers  20 ,  16  and  18 . The portions of the flexible strap fingers  20 ,  16  and  18  which slide through and are held in place by the two collars  12  and  14  form the flexible strap fingers area  15  and  17 . 
     Referring now to FIG. 4, there is shown a front perspective view of the centralizer  10  constructed in accordance with the present invention. The collars  12  and  14  attach to the straps  16 ,  18 ,  20  and  22  and are held in place by the collar locking ramps located on the bottom of the straps  16 ,  18 ,  20  and  22  as exemplified by collar locking ramp  27 . The straps are thus spaced equidistant from each other around a given circumference. The end portions of the straps which pass through the collars  12  and  14  are the flexible strap finger portions as exemplified by flexible strap fingers  21  and  23 . The flexible strap fingers  21  and  23  have well rounded edges as exemplified by well rounded edge  26  for user safety. Strap gussets as exemplified by strap gusset  24  provide additional reinforcement to the straps  16 ,  18 ,  20  and  22 . 
     Each of the flexible strap fingers  21  and  23  has a tie wire slot as exemplified by tie wire slots  32  and  34 . The end portion of the flexible strap fingers  21  and  231  which are adjacent to the tie wire slots  32  and  34  form a raised end ramp as exemplified by raised end ramp  30 . This end ramp  30  portion provides a user with ease in assembly. In addition, the end ramp  30  has the primary function to prevent a tie wire from coming off the centralizer, securing and retaining the tie wire. The flexible strap fingers  21  and  23  have two locking tabs on the interior surface of the centralizer  10  straps as exemplified by lock tab  27 . The lock tabs  27  fit snugly in place against the outer rim of the collars when assembled. The locking tab  27  holds the collar snugly and does not allow for any movement. 
     Compression tabs are located on the inner surface of each flexible finger portion of each strap. Such a compression tab is exemplified by compression tab  28 . When the flexible finger portions of the straps are compressed into place around an elongated object to be centrally positioned in a bore hole, the compression tab  28  fits around the surface to enhance connection and mounting of the centralizer. Compression tab  28  may also fit directly into grooves such as those found in corrugated pipe. In this way the centralizer will not slip. 
     The collars  12  and  14  are also provided with a plurality of grout passage spaces, as exemplified by grout passage spaces  36  and  38 . 
     Turning to FIG. 5, there is shown a back perspective view of an unassembled rigid strap  40 . Each strap  40  is provided with a strap gusset  42  located on the midline of the strap rise  43 . The strap gusset  42  is at its maximum width in the center of the strap rise  43  giving the most support at the point of greatest strain on the strap  40  during use. The strap gusset  42  provides reinforcement for the strap rise  43  which allows the strap rise  43  to be manufactured with less weight and less material, yet maintains the stability and strength of a much heavier strap rise. Those portions of the unassembled strap  40  which would extend past the holding collars form the flexible strap finger  44  and  46 . The compression tabs  48  and  50  are clearly seen in this view as are the collar lock ramps  72  and  74 . The bottom collar stoppers  66  and  68  which are extensions of the ends of the strap rise are also seen here. All surfaces have a well rounded edge as exemplified by well rounded edge  41 . 
     Referring now to FIG. 6, there is seen a front perspective view of an unassembled strap  40 . All surfaces of the unassembled strap  40  have a well rounded edge  41 . A portion of the strap gusset  42  is seen running along the midline of the strap rise  43 . The flexible strap fingers  44  and  46  are located on the end portions of the unassembled strap  40  on either side of the grooved collar fastening points  62  and  64 . The portion on the strap  40  which includes the grooved collar fastening points  62  and  64  and the flexible strap fingers  44  and  46  are standard on all rigid straps  40 . The grooved collar fastening points  62  and  64  enable the manufacturer to keep the material thickness constant to improve the cycle time of the molding process. In addition, the grooved collar fastening points  62  and  64  produce less friction when installing the collar and allows grout to flow inside to seal. The compression tabs  48  and  50  are located on the back of the strap in alignment with the tie wire slots  52  and  54 . Next to the tie wire slots  52  and  54  are the raised end ramps  56  and  58 . 
     FIG. 7 is a side view of an unassembled strap  40 . The strap gusset  42  runs the entire length of the strap rise  43  along the longitudinal midline of the strap rise  43 . The bottom collar stoppers  66  and  68  are seen here as extensions of the strap rise  43  and strap gusset  42 . The grooved collar fastening points  62  and  64  are adjacent to the strap rise  43 . 
     The flexible strap fingers  44  and  46  begin past the grooved collar fastening points  62  and  64 , and support the compression tabs  48  and  50  on the bottom side of the tie wire slots  52  and  54 . The terminal ends of the flexible strap fingers are raised end ramps  56  and  58 . Collar lock ramps  72  and  74  are located on the back side of the grooved collar fastening points  62  and  64 . 
     Referring to FIG. 8, there is seen an enlarged plan view of the unassembled strap  40 . All of the edges of the unassembled strap  40  have well rounded edges as exemplified by well rounded edge  41 . A grooved collar fastening points  62  is located at the end of the rise  43 . A portion of the bottom collar stopper  66  may be seen from this view. The compression tab  48  as well as a portion of the collar lock ramp  72  are also seen from this view. The strap rise  43  width increases at the top of the rise  43  which allows for more surface contact and prevents digging into soft soils. In this way the centralizer strap act like a sled when lowering elongated objects to be centrally located into a bore hole. The width increases proportionally to the rise  43  of the strap  40 . 
     Referring now to FIG. 9, an enlarged perspective view of a second embodiment  80  of one of the component collars is shown. This embodiment  80  provides three collar slots  82 ,  84  and  86  for three straps (see strap  40  above). In addition another embodiment of the previously described grout passage  83  is shown. In describing FIG. 4, the grout passage  36  on collar  12  had four portions. The present embodiment of the grout passage  83  on collar  80  has three portions. As before, these portions are bounded by slot sides  85 . In this embodiment, collar  80 , the slot sides  85  meet at angle  87 . In either grout passage  83 , a housing  88  may be laid to house a cable strand or to provide an additional passage way for grout through a grout tube. In fact, such a housing  88  may be laid in between any two adjacent collar slots (for example here between  82  and  84  or  84  and  86  or  82  and  86 ) in any collar or grout passage embodiment described herein. 
     Still describing FIG. 9, still another embodiment of the collar  80  may be used. At the angle  83 , or between any other two slot sides, a single slit  89  may be cut into one or more of the collars to allow a user to manually spread the collar to snap over an anchor “rebar”, rebar or strand encapsulated with corrugated pipe, or cable. This embodiment may be immensely practical and advantageous depending on the application on-site. The single slit  89  may even be made on-site. Only one such single slit  89  may be made in each of the collars or else collar integrity will be compromised. 
     Referring to FIG. 10, an enlarged perspective view of a typical embodiment of one of the standard collars  90  (similar to previously described collar  12 ) is shown. This embodiment collar  12  has four slots  92 ,  94 ,  96  and  98  to accommodate four straps (see strap  40  above). 
     Next referring to FIG. 11, an enlarged perspective view of a preferred embodiment of one of the typical collars  100  is shown. This embodiment of collar  100  has five slots  101 ,  102 ,  103 ,  104  and  105  for five straps (see strap  40  above). 
     Finally, referring to FIG. 12, an enlarged perspective view of another embodiment of one of the typical collars  110  is shown. This embodiment of collar  110  has six slots  111 , 112 , 113 , 114 , 115  and  116  for six straps (see strap  40  above). It should be pointed out that as collar size increases, that is, as collars increase in capacity to accommodate more straps, the grout passages therein become more in number as well as wider in size, thereby allowing greater grout flow between centralizers placed into varying applications on job sites. 
     Referring now to FIG. 13 there is shown a front elevational perspective view of the fully assembled centralizer  10  constructed in accordance with the present invention. The collars  12  and  14  hold the straps  16 ,  18 ,  20  and  22 . The portions of the straps which pass through the collars  12  and  14  and are above the grooved collar fastening points as exemplified by grooved collar fastening points  64  are the flexible strap finger portions as exemplified by flexible strap fingers  21  and  23 . These flexible strap fingers  21  and  23  collectively form the flexible strap fingers area  15  and  17 . 
     Each of the flexible strap fingers  21  and  23  each has a tie wire slot as exemplified by tie wire slots  32  and  34 . The tie wire slots  32  and  34  are wide enough to accommodate zip ties as well as wire. The end portion of the flexible strap fingers  21  and  23  adjacent to the tie wire slots  32  and  34  and form a raised end ramp as exemplified by raised end ramp  30 . This end ramp  30  portion provides a user with ease in assembly, and prevents tie wire slippage. In addition, the flexible strap fingers  21  and  23  have compression tabs on the interior surface of the centralizer  10  as exemplified by compression tab  28 . The compression tabs  28  fit snugly in place against the outer surface of the object to be centralized such as bar thread, corrugate pipe or corrugated sheathing duct. 
     The collars  12  and  14  are also provided with a plurality of grout passages as exemplified by grout passages  36  and  38 . The size of the grout passages  36  and  38  allows for a strand fixture or grout tube. 
     In FIGS. 14 through 21 a novel multiple configuration centralizer system embodiment is illustrated. This multiple configuration centralizer system is composed of standardized parts which are interchangeable and may be assembled and fastened to an anchor quickly and conveniently, on the job site, without the use of conventional tools. 
     Referring now to FIG. 14, a tie retainer clip  130  is illustrated. The tie retainer clip  130  has a thick walled upper surface  132  and clip fastening tines  134 ,  136  and  138  which are separated by spaces  144  and  146  to accept strap ridges at the grooved portion  64  of each strap  16  (as shown in FIG.  13 ). The tie retainer clip  130  is a standard size which accommodates all collars. A slot  142  for ties is located between the thick walled upper surface and the clip fastening tines  134 ,  136  and  138  and is constructed to provide a snug friction grip fit over zip ties. 
     Turning now to FIG. 15, there is seen a strap housing  120  consisting of tapered flexible arms as exemplified by tapered flexible arm  122  and a thick walled rounded body  126 . The flexibility of the tapered flexible arm  122  allows the strap housing  120  to adapt to various diameters of objects to be centralized. The strap housing  120  is standard and manufactured to fit all rigid straps. It also forms a “saddle” to prevent side shifting of the strap housing  120  when fastened or mounted to an anchor. The thick walled rounded body  126  retains straps and also prevents side movement of straps. A curved inner surface  128  is positioned frictionally on the outer perimeter of a device to be centralized. A slot  124  to accept a tie retainer clip is formed within the thick walled rounded body  126  of the strap housing  120 . 
     Referring now to FIG. 16, a strap housing/tie retainer clip assembly  150  is seen. A portion of the strap  152  and the rounded strap edge  154  as well as a strap gusset  156  are shown. A strap housing  120  with one of the tapered flexible arms  122  is shown as it would appear when mounted over the finger section  158  of strap. The collar lock ramp  164  keeps the strap housing  120  locked in this position. The collar lock ramp  164  is tapered to allow the strap housing  120  to slip on easier. The tie retainer clip  130  has been positioned with the clip fastening tine  134  inserted into the grooved collar fastening point  160  and held in place by several tie retainer clip lock ramps as exemplified by tie retainer clip lock ramp  162  in a cut away section of the strap housing  120 . A slot  142  for accepting a zip tie remains open for insertion of the zip tie. 
     Turning to FIG. 17, a strap housing/tie retainer clip assembly  150  is illustrated with tie wires  168  running through the tie wire slot  170  and zip tie  166  as it would be seen when inserted through the slot  142  for tie. A portion of the strap  152  and the rounded strap edge  154  as well as a strap gusset  156  are shown. An elevated side perspective view of the strap housing  120  with one of the tapered flexible arms  122  is shown as it would appear when mounted over the grooved collar fastening point  160  of strap  152 . The raised end ramp  172  helps to guide the tapered flexible arm  122  through the strap housing  120  and helps prevent the tie wire  168  from slipping off the strap housing/tie retainer clip assembly  150 . The tie retainer clip  130  has been inserted into the grooved collar fastening point  160 . The compression tab  174  is located on the back side of the strap  152  below the tie wire slot  170  and fits snugly on the outer surface of an object to be centralized. 
     Referring now to FIG. 18 there is seen a multiple strap centralizer assembly  180  consisting of several straps as exemplified by straps  182  and  184 . Tie retainer clips  186 ,  188 ,  190  and  191  are held in place by the strap housings  194 ,  196 ,  198  and  202  which slip through the straps  182  and  184 . Zip ties  204  and  206  form a friction fit through the tie retainer clips  186 ,  188 ,  190  and  192  and maintain the distance between straps  182 ,  184  at set intervals on the multiple strap centralizer assembly  180 . The multiple strap centralizer assembly  180  is held in place on the corrugated pipe or rebar  176  by the constriction of the zip ties  204  and  206  and by tie wires  208  and  210 . 
     FIG. 19 shows a plan view of a 4-strap centralizer assembly  220  mounted on a corrugated pipe or rebar  218 . The strap housings  232 ,  244 ,  236  and  238  are mounted to the straps  222 ,  224 ,  226  and  228  with the tie retainer clips  242 ,  234 ,  246  and  248  inserted into the strap housings  232 ,  234 ,  236  and  238 . The zip tie  230  is inserted through the tie retainer clips  242 ,  234 ,  246  and  248  and frictionally maintain the distances between the straps  222 ,  224 ,  226  and  228 . The zip tie  230  when cinched down tightly, together with the tie wire  231  help hold the 4-strap centralizer assembly  220  in place when mounted on any elogated object to be centrally positioned within a bore hole, such as corrugated pipe or rebar  218 . 
     Turning to FIG. 20, an 8-strap centralizer assembly  250  is illustrated. The strap housings  268 ,  270 ,  272 ,  274 ,  278 ,  280 ,  282  and  284  are mounted to the straps  252 ,  254 ,  256 ,  258 ,  260 ,  262 ,  264  and  266  with the tie retainer clips  286 ,  288 ,  290 ,  292 ,  294 ,  296 ,  298  and  300  inserted into the strap housings  268 ,  270 ,  272 ,  274 ,  278 ,  280 ,  282  and  284 . The zip tie  302  is inserted through the tie retainer clips  286 ,  288 ,  290 ,  292 ,  294 ,  296 ,  298  and  300  and frictionally maintain the distances between the straps  252 ,  254 ,  256 ,  258 ,  260 ,  262 ,  264  and  266 . The zip tie  302  when cinched down tightly together with the tie wire  304  help hold the 8-strap centralizer assembly  250  in place when mounted on a corrugated pipe or rebar  249 . 
     FIG. 21 shows a 6-strap ladder assembly  310  as it would be seen as shipped and prior to mounting on pipe, corrugated sheathing, rebar, or any other large diameter anchor. The strap housings  324 ,  328 ,  332 ,  336 ,  340  and  344  are mounted to the straps  312 ,  314 ,  316 ,  318 ,  320  and  322  with the tie retainer clips  326 ,  330 ,  334 ,  338 ,  342  and  346  inserted into the strap housings  324 ,  328 ,  332 ,  336 ,  340  and  344 . The zip ties  348  and  350  are inserted through the tie retainer clips. For example zip tie  350  is inserted through tie retainer clips  326 ,  330 ,  334 ,  338 ,  342  and  346  and frictionally maintain the distances between the straps  312 ,  314 ,  316 ,  318 ,  320  and  322  during shipping but the distances between the straps  312 ,  314 ,  316 ,  318 ,  320  and  322  may be adjusted in the field without the use of tools. 
     In the field, the radius of the riser portion of the rigid strap determines the size selection of the rigid strap to use in a given bore hole application. Please refer to Table 1. below for the Rigid Centralizer Sizing Chart. 
     
       
         
               
             
               
               
               
             
               
             
               
               
               
             
               
             
               
               
               
             
               
             
               
               
               
             
               
             
               
               
               
             
               
             
               
               
               
             
               
             
               
               
               
             
           
               
                 TABLE 1 
               
             
             
               
                   
               
               
                 RIGID CENTRALIZER SIZING CHART 
               
             
          
           
               
                   
                 Strap Rise 
                 Overall Size 
               
               
                   
                 (inches) 
                 (inches) 
               
               
                   
                   
               
             
          
           
               
                 1) 1.25″ I.D. collar with 1.50″ cross-section: 
               
             
          
           
               
                   
                 1.00 
                 3.50 
               
               
                   
                 1.25 
                 4.00 
               
               
                   
                 1.50 
                 4.50 
               
               
                   
                 1.75 
                 5.00 
               
               
                   
                 2.00 
                 5.50 
               
               
                   
                 2.25 
                 6.00 
               
               
                   
                 2.50 
                 6.50 
               
               
                   
                 2.75 
                 7.00 
               
               
                   
                 3.00 
                 7.50 
               
               
                   
                 3.25 
                 8.00 
               
             
          
           
               
                 2) 1.50″ I.D. collar with 1.75″ cross-section: 
               
             
          
           
               
                   
                 1.00 
                 3.75 
               
               
                   
                 1.25 
                 4.25 
               
               
                   
                 1.50 
                 4.75 
               
               
                   
                 1.75 
                 5.25 
               
               
                   
                 2.00 
                 5.75 
               
               
                   
                 2.25 
                 6.25 
               
               
                   
                 2.50 
                 6.75 
               
               
                   
                 2.75 
                 7.25 
               
               
                   
                 3.00 
                 7.75 
               
               
                   
                 3.25 
                 8.25 
               
             
          
           
               
                 3) 1.75″ I.D. collar with 2.00″ cross-section: 
               
             
          
           
               
                   
                 1.00 
                 4.00 
               
               
                   
                 1.25 
                 4.50 
               
               
                   
                 1.50 
                 5.00 
               
               
                   
                 1.75 
                 5.50 
               
               
                   
                 2.00 
                 6.00 
               
               
                   
                 2.25 
                 6.50 
               
               
                   
                 2.50 
                 7.00 
               
               
                   
                 2.75 
                 7.50 
               
               
                   
                 3.00 
                 8.00 
               
               
                   
                 3.25 
                 8.50 
               
             
          
           
               
                 4) 2.00″ I.D. collar with 2.25″ cross-section: 
               
             
          
           
               
                   
                 1.00 
                 4.25 
               
               
                   
                 1.25 
                 4.75 
               
               
                   
                 1.50 
                 5.25 
               
               
                   
                 1.75 
                 5.75 
               
               
                   
                 2.00 
                 6.25 
               
               
                   
                 2.25 
                 6.75 
               
               
                   
                 2.50 
                 7.25 
               
               
                   
                 2.75 
                 7.75 
               
               
                   
                 3.00 
                 8.25 
               
               
                   
                 3.25 
                 8.75 
               
             
          
           
               
                 5) 2.43 I.D. collar with 2.625″ cross-section: 
               
             
          
           
               
                   
                 1.00 
                 4.625 
               
               
                   
                 1.25 
                 5.125 
               
               
                   
                 1.50 
                 5.625 
               
               
                   
                 1.75 
                 6.125 
               
               
                   
                 2.00 
                 6.625 
               
               
                   
                 2.25 
                 7.125 
               
               
                   
                 2.50 
                 7.625 
               
               
                   
                 2.75 
                 8.125 
               
               
                   
                 3.00 
                 8.675 
               
               
                   
                 3.25 
                 9.125 
               
             
          
           
               
                 6) 2.75″ I.D. collar with 3.00″ cross-section: 
               
             
          
           
               
                   
                 1.00 
                 5.00 
               
               
                   
                 1.25 
                 5.50 
               
               
                   
                 1.50 
                 6.00 
               
               
                   
                 1.75 
                 6.50 
               
               
                   
                 2.00 
                 7.00 
               
               
                   
                 2.25 
                 7.50 
               
               
                   
                 2.50 
                 8.00 
               
               
                   
                 2.75 
                 8.50 
               
               
                   
                 3.00 
                 9.00 
               
               
                   
                 3.25 
                 9.50 
               
               
                   
                   
               
               
                   
                 NOTE: When sizing centralizers, 0.25″ must be added to the collar I.D. This is the typical collar wall thickness × 2. Therefore, a 1.25″ I.D. collar measures 1.50″ + strap rise × 2 = centralizer O.D.  
               
             
          
         
       
     
     The present invention improves or provides the solutions to the many problems previously associated with centralizers. Just a few of those solutions described herein include simplifying and improving the locking mechanism of the straps into the collars, incorporating a multiple configuration centralizer device readily assembled from standardized components to adapt to various diameter bore holes and anchors, improving the grout passage, eliminating the need for use of conventional tools in assembly of the centralizer, and a greatly lowered cost of manufacturing because of the use of a lightweight, moldable, and strong material. Now, many applications may be served by the present invention, instead of each application requiring a separately designed and expensively manufactured centralizer device. 
     It should be understood, however, that even though these numerous characteristics and advantages of the invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, chemistry and arrangement of parts within the principal of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.