Abstract:
A piping system for conveying one or more product flow lines within an outer casing includes insulation members on the product flowline(s) to prevent heat lost and an improved spacer arrangement forming an interface between the product flow lines and the casing to prevent damage to the casing and flow lines as well as reduce friction when the flow lines are pulled through the casing. The insulation members includes a plurality of halves that can be assembled together circumferentially and end-to-end. In one embodiment, a frame carries a U-shaped insulation member that is polymeric and foam filled. The frame is ballasted so that it can be towed to a job site underwater yet buoyant and above the seabed, then lowered onto the pipeline by flooding the ballast tanks.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     Priority of U.S. Provisional Patent Application Ser. No. 60/087,989, filed Jun. 4, 1998, incorporated herein by reference, is hereby claimed. 
     U.S. patent application Ser. No. 09/057,843, filed Apr. 9, 1998, is incorporated herein by reference. 
     U.S. Provisional Patent Application Ser. No. 60/056,227, filed Aug. 21, 1997, is incorporated herein by reference. 
     U.S. Provisional Patent Application Ser. No. 60/087,989, filed Jun. 4, 1998, is incorporated herein by reference. 
     Disclosure Document No. 411,183, filed Jan. 21, 1997, is hereby incorporated by reference. In accordance with M.P.E.P. Section 1706, please retain Disclosure Document No. 411,183, filed Jan. 21, 1997 and entitled “PIPE WITHIN A PIPE FLOWLINE BUNDLE SPACER”. 
    
    
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     Not applicable 
     REFERENCE TO A “MICROFICHE APPENDIX” 
     Not applicable 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to marine piping and piping assemblies, and more particularly to an assembly that includes an outer casing with one or more smaller insulated flow lines disposed within the outer casing and a plurality of foam filled shell insulation members and spacers positioned along the flow lines at intervals, the spacers being configured to enable the product flow lines to be pulled through the outer casing during placement. The shell insulation members include polymeric material that encapsulates the foam, isolating it from the surrounding marine environment. 
     2. General Background of the Invention 
     With the advent of deep-water hydrocarbon production from depths exceeding 3,000 feet below mean seal level (msl) one of the methods for installing production flow lines has been to install one or more production flow lines inside an outer carrier or casing pipe. The casing pipe and flow line(s) are pre-welded in long lengths and then the flow line(s) are pulled into the casing pipe by means of a pull winch. The flow line(s) normally has a rigid polyisocyanurite insulation jacket complete encircling the line to keep the hydrocarbon from losing heat. This insulation must be protected from dragging against the casing or it will become torn, dismembered, or ruptured. The insulation jacket must fit snugly against the spacer and sealed in order not to allow heat transfer to take place. 
     This type of insulated pull-in piping segments are used in both the bottom tow flow line bundle method for installing long land fabricated cased flow line bundle segments that are towed on the ocean bottom to their final installation point and the reel barge method of laying cased flow lines segments that are put together on land, reeled onto the spool barge and then unreeled at the final installation point. 
     Since this is relatively new technology there have been very few previous projects in the scope of this invention. Previous approaches have required spacers on land and marine cased crossings to use numerous thin short pull spacers to be placed 5-7 feet apart. These spacers were designed to withstand minimal drag and pressure to be exerted on the part and were used to pull a short section of flow line 300 feet or less into a casing pipe. 
     Several patents have issued that disclosed generally the concept of disposing one pipe or conduit inside of another and wherein spacers form an interface between the inner and outer pipes. The Bond U.S. Pat. No. 2,706,496 discloses a concentric pipe insulator and spacer that includes a plurality of longitudinally extending ribs connected with cable, each of the ribs providing two spaced apart rollers that are provided to contact an outer casing. 
     In the Cotman U.S. Pat. No. 3,213,889, there is provided a pipe support in the form of a collar that surrounds an inner pipe disposed within an outer pipe. 
     The Mowell U.S. Pat. No. 3,379,027 discloses a roller supported LNG pipeline that includes an inner pipe having a plurality of rollers extending from the outer surface thereof and wherein the rollers contact the inner wall of an outer casing. 
     In the Lutchansky U.S. Pat. No. 3,786,379, there is provided a wave-guide structure that utilizes roller spring supports for supporting a waveguide in a conduit to simultaneously provide a compliance support and allow free relative longitudinal movement between the waveguide and the conduit. A tension band having a plurality of spring assemblies integrally formed therewith is fastened about eh periphery of the waveguide. Rollers are mounted on the spring assemblies in contact with the conduit to allow free relative longitudinal movement of the waveguide and conduit. The spring assemblies provide a soft compliant support through a range of deflections accommodating the worst expected thermal loading conditions in route bends. Under higher loading the spring assemblies bottom out and provide a stiff support to prevent further radial deflection of the waveguide with respect to the conduit. 
     A cryogenic fluid transfer line is provided in U.S. Pat. No. 4,233,816 which comprises an interior conduit for passage therethrough of cryogenic fluid, an exterior conduit concentrically spaced about the interior conduit and defining the exterior of the fluid transfer line, an annular heat transfer shield generally concentric with and interjacent to the interior and exterior conduits and including at least one longitudinally extending resilient arcuate member with a longitudinally extending generally arcuate hooking edge, at least one longitudinally extending resilient arcuate member with a longitudinally extending generally arcuate catching edge, where the hooking and catching edge members are interlockingly engageable with each other when the member including the hooking edge is flexed to a smaller arcuate radius, positioned with its hooking edge inboard of the catching edge and then permitted to relax, each set of engaged hooking and catching edges defining a hollow generally cylindrical next having a substantially closed curved surface with each next extending longitudinally substantially the length of the shield, with the shield further including longitudinally extending heat transfer conduits resident within each nest. Radiation shields are provided between the annular heat transfer shield and the interior and exterior conduits. 
     An underground pipe support device is the subject of U.S. Pat. No. 4,896,701 for supporting an underground pipe or cable within the encasement sleeve of a horizontally bored hole. The support device includes a round collar having two resiliently spaced-apart ends which can be urged together to secure the device to the underground pipe or cable. A plurality of equidistantly spaced-apart and outwardly extending support legs are provided around the circumference of the collar which terminate in an elongate foot having opposing ends inclined inwardly toward the collar. Each foot extends generally parallel to the longitudinal axis of the collar and has a greater length than the longitudinal length of the collar to facilitate placement and support of an underground pipe or conduit within the encasement sleeve of the underground hole. 
     The Muszynski U.S. Pat. No. 5,069,255 discloses a pipeline casing insulator to support a coated pipe within a tubular metallic casing. The pipeline casing insulator comprises a flexible belt formed of a material that is capable of bonding to an organic resin. A plurality of parallel bar-like runners are formed from an insulative and non-abrasive polymer concrete that is cast onto an outer facing surface of the belt. The belt is preferably a strip of an organic non-woven material. The polymer concrete is preferably a mixture of a thermosetting polymer resin, such as epoxy, polyester or polyurethane, and an aggregate. The aggregate preferably comprises a mixture of substantially incompressible coarse particulate material, such as sand or gravel, and fine filler material, such as calcium carbonate, silica flour, or kaolin. The inner facing surface of the belt preferably has a mastic coating covered by a release paper that can be removed, to allow attachment of the belt to the outer surface of the pipe by circumferentially wrapping the belt around the pipe. 
     A casing spacer that includes first and second elongated, steel shell members is disclosed in the Eskew U.S. Pat. No. 5,441,082. The casing spacer is comprised of stainless steel or high strength steel with corrosion inhibiting coatings, with each shell member having a semi-circular cross section for engaging and enclosing a carrier pipe within an outer casing. Attached to the outer surface of each of the first and second shell members are one or more adjustable risers for engaging the inner surface of the casing in maintaining the pipe, or pipes, in fixed position within the casing. Each riser includes a runner on its distal end to facilitate positioning of the spacer within the casing. The casing spacer&#39;s first and second shell members are securely coupled together by way of flange and nut and bolt combinations along one edge and a hook and eye arrangement along a second, opposed edge. The hook portion of one shell member is easily inserted in the eye portion of the second shell member followed by tightening of the nut and bolt combinations allowing a single worker to easily and quickly install the spacer about a carrier pipe and within a casing. 
     In the Morris U.S. Pat. No. 5,503,191 a length of elongate material such as rubber hose is supported and guided while being fed along a desired path of travel that extends through the hollow interior of a tubular structure. The tubular structure mounts an array of relatively closely spaced rollers that project into the hollow interior to guide and support the moving length of material. The tubular structure is formed as a “tube within a tube” assembly of “inner” and “outer” tubular members that closely interfit, and that sandwich roller support pins between overlying portions of the inner and outer tubular members. The roller support pins bridge roller positioning holes that are formed through the inner tubular member at an array of spaced locations. The rollers are rotatably mounted by the support pins and project through the positioning holes into the hollow interior of the tubular structure to engage outer surface portions of such elongate material as is being fed through the tubular structure to prevent the moving material from contacting stationary portions of the tubular structure. In preferred practice, a funnel-like roller-carrying end assembly is provided near one end of the tubular structure to define a constricted discharge opening through which the moving material discharges. 
     A glide tube ring for tube-in-tube systems is disclosed in U.S. Pat. No. 5,592,975. The glide ring tube according to the invention is provided with axially spaced glides running parallel to each other whose material has the lowest possible friction coefficient, especially a plastic, preferably a fiberglass-reinforced polyethylene, polyamide or the like, in which the glide tube ring is attached to the central tube forming a closed ring that centers this tube in the protecting tube, pipe conduit or the like. 
     BRIEF SUMMARY OF THE INVENTION 
     The present invention addresses the aforementioned problems encountered in the prior art by providing a flow line(s) spacer/centralizer which is manufactured to adjoin the insulating jacket, protect the insulation from the casing pipe, act as a dragging surface for the installation of the flow line(s) inside the casing for longer sections, allow multiple flow lines of various sizes to be bundled and inserted at the same time, by adding wheels to replace the ear section on the spacer body allowing the installation contractor to pull longer sections with fewer sectional tie-in welds on both the flow line(s) and casing thereby speeding up the installation time and reducing cost. The present invention requires only one spacer per 40-foot pipe joint to be installed, saving labor, speeding installation and lowering cost. 
     The present invention thus provides an improved piping assembly having an outer casing with an annular containment space for holding one or more product flow lines, the casing having a bore and an inner wall portion surrounding the bore. 
     One or more product flow lines is surrounded by insulation and positioned within the outer casing, the insulation having a generally cylindrically-shaped outer surface that has a diameter smaller than the diameter of the casing bore. 
     A plurality of spacers are positioned along the flow lines at intervals, each spacer having projecting portions for engaging the inner wall of the casing or having the proper full body diameter to contact the inner wall of the casing when the product flow lines are pulled through the casing. In small pipe-in-pipe bundles where tolerances are very close (±0.125 inch) there is no space for an ear section. For example, a 6″×10″ centralizer with 1.5″ body thickness may not have ears. 
     Each spacer includes a pair of halves that can be assembled together about the flow line, each half being an integral member that includes a body, flanged portions, and optionally projecting portions with drag surfaces thereon. 
     Each of the halves includes corresponding flanged portions that abut face-to-face upon assembly of the halves. A bolted connection is used for example to assemble the halves together at the flanged portions. Alternatively, bolts may go through the body of the spacer itself. 
     The projecting portions extend longitudinally and radially with respect to the central axis of the flow line. Each half has at least a pair of projecting portions thereon. Each half has annular shoulder fore and aft that mate with adjacent insulation to avoid heat loss. 
     A layer of insulation can be provided that surrounds the flow line. The insulating barrier can be a ceramic latex paint put on the outside surface of the product flow line. 
     Insulation for the flow lines can include a first layer of insulation of foam, and second and third layers of insulation that surround the flow line and the foam, the second and third layers being metallic foil layers. 
     The inside diameter of the outer casing pipe can be coated with an insulating barrier such as a ceramic latex paint that will enhance the reflective capacity of the outer casing pipe to prevent the colder temperatures from entering the casing, thereby allowing more heat to stay inside the product flowline area. 
     The insulation can be in the form of a hollow shell of polymeric material such as high density polypropylene, nylon or the like. This shell is sealed about an inner insulating material such as foam. The outer polymeric shell prevents attack of the foam by surrounding sea water and the marine environment by surrounding the foam with the impervious plastic polymeric material. 
     In one embodiment, the shelled insulation material is in the form of a plurality of sections that can be interlocked together. For example, in one embodiment, the shells are in the form of semicircular sections that are longitudinally extending. Mating faces of the shells interlock longitudinally. Male and female projecting end portions of the shell insulation members can then be connected end to end. Correspondingly shaped spacers can be placed at intervals to form a connection with the insulation members and to space the pipe from the outer casing. 
     In another embodiment, the shell is in the form of a semicircular insulation member that is carried by a frame having a U-shaped member with spaced apart side walls that straddle the pipe. In this embodiment, the semicircular insulation member conforms to the pipe. The frame extends over the pipe and covers it even when the pipe is embedded in the seabed at or below the mud line. The insulation member can be supported by ballast pipes that enable it to be towed to a job site about midway between the water surface and the seabed if desired. The ballasting material can then lower the apparatus to the seabed where it can engage and insulate a pipe that is an existing flowline on the seabed. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     For a further understanding of the nature, objects, and advantages of the present invention, reference should be had to the following detailed description, read in conjunction with the following drawings, wherein like reference numerals denote like elements and wherein: 
     FIG. 1 is a perspective view of the preferred embodiment of the apparatus of the present invention; 
     FIGS. 1A and 1B are schematic match line plan views illustrating a part of the method of the present invention; 
     FIG. 2 is a fragmentary plan view illustrating part of the method of the present invention; 
     FIG. 3 is a fragmentary end view of the preferred embodiment of the apparatus of the present invention showing the spacer; 
     FIG. 4 is another fragmentary end view of the preferred embodiment of the apparatus of the present invention showing the spacer; 
     FIG. 5 is a sectional view taken along lines  5 — 5  of FIG. 4; 
     FIG. 6 is a fragmentary side, elevational, partially cut away view of the preferred embodiment of the apparatus of the present invention showing the insulation members; 
     FIG. 7 is a sectional view taken along lines  7 — 7  of FIG. 6; 
     FIG. 8 is a fragmentary view of the preferred embodiment of the apparatus of the present invention showing the inner pipe, weld cap and padeye; 
     FIGS. 9-12 are schematic views illustrating part of the method of the present invention; 
     FIG. 13 is a partial end view of the preferred embodiment of the apparatus of the present invention showing the inner pipe, spacer and outer casing; 
     FIG. 14 is a partial sectional, elevational view of the preferred embodiment of the apparatus of the present invention; 
     FIG. 15 is a side, elevational view of a second embodiment of the apparatus of the present invention; 
     FIG. 16 is a partial elevational view of the second embodiment of the apparatus of the present invention showing the insulation member; 
     FIG. 17 is a sectional view taken along lines  17 — 17  of FIG. 16; 
     FIG. 18 is a partial end view of the second embodiment of the apparatus of the present invention; 
     FIG. 19 is a partial end, sectional view of the second embodiment of the apparatus of the present invention; 
     FIG. 20 is a plan view illustrating the method of the present invention; 
     FIG. 21 is a side elevational view illustrating the method of the present invention; 
     FIG. 22 is a partial side elevational view of the second embodiment of the apparatus of the present invention; 
     FIG. 23 is a side elevational view illustrating the method of the present invention; 
     FIG. 24 is a transverse sectional view of the second embodiment of the apparatus of the present invention shown in position on a pipeline located on a seabed; 
     FIG. 25 is a side elevational view illustrating the method of the present invention; and 
     FIG. 26 is a plan view illustrating the method of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     In FIGS. 1,  1 A and  1 B, there can be shown the initial part of the method of the present invention wherein match line A—A of FIG. 1A matches line A—A of FIG.  1 B. An inner pipe assembly  10 A is constructed of multiple lengths of pipe welded together end to end. The inner pipe assembly  10 A is pulled into an outer pipe or casing  11 , beginning at trough T of casing  11  (see FIGS.  2  and  9 - 12 ). Inner pipe assembly  11  includes a weld cap  37  with a padeye  38  to which cable C is attached. 
     Side booms or like pipe handling equipment can be used to preliminarily position casing sections  11 . A number of lengths of casing  11  can then be assembled (eg. welded) end to end. Inner pipe assembly  10 A is pulled into casing  11  using commercially available pulling equipment such as the winch W and winch cable C in FIG.  1 B. 
     In FIGS. 9-12, the method of the present invention shows the preliminary step of connecting cable C to inner pipe member  10 A at weld cap  37  and padeye  38 . Cable C is pulled by winch W in the direction of arrow  39  pulling inner pipe member  10 A into the bore  16  of casing  11 . As the inner pipe  10 A is pulled in the direction of arrow  39 , shell halves  28 A,  28 B are added to the inner pipe  10 A. Additionally, spacer halves  26 A,  26 B are added as shown in FIG.  12 . The arrows  40  in FIG. 12 indicate the assembly of spacer halves  26 A,  26 B and shell halves  28 A,  28 B to pipe  10 A. In FIGS. 10-12, the assembled inner pipe member  10 A is covered with a plurality of shells  28  with spacers  26  positioned at intervals. 
     FIG. 1 shows generally a first embodiment of the apparatus of the present invention designated by the numeral  10  in FIG.  1 . Piping assembly  10  includes an outer casing  11  having a generally cylindrically-shaped wall  12 . Wall  12  provides an outer surface  13  and an inner surface  14 , both generally cylindrically shaped. 
     Casing  11  can have a drag coating surface  15  so that it can be pulled during installation across a seabed, for example. Casing  11  has a hollow bore or annular containment space  16  for containing an inner pipe assembly  10 A that can include one or more product flow lines  17 ,  21 . The inner pipe assembly  10 A includes one or more inner metallic pipe member  17 , each having a bore  18  and covered with a coating. The product flow line  17  has a longitudinally extending flow bore  18  that is surrounded by cylindrically-shaped wall  19  having an outer cylindrically-shaped surface  20 . Similarly, the product flow line  21  has flow bore  18 , wall  19 , and outer surface  20 . 
     The two product flow lines  17 ,  21  can be surrounded by preferably three layers of insulation. This includes a first thickest insulation layer  22  that can be of polymeric foam, for example. On the outer surface of insulation layer  22 , there is provided outer foil layer  23  that is also an insulating layer, being of a foil metallic material. Inner foil layer  24  provides another insulating layer in between the flow lines  17 ,  21  and foam insulation layer  22 . Ceramic latex paint can be applied to the outer surface  20  of the two product flow lines  17 ,  21  to add another insulating layer. 
     A plurality of spacer bodies  26  are disposed at intervals along the flow lines  17 ,  21  (e.g., one per 40′ joint of pipe). In between two successive spacer bodies  26 , the insulation  22 ,  23 ,  24  is provided. Each spacer has fore and aft annular shoulders  26 C that mate with the adjacent insulation  22 ,  23 ,  24  to eliminate heat loss. This provides an outer cylindrical surface  25  of the insulation layers  22 ,  23 ,  24  that is correspondingly configured to mate with an outer cylindrical surface  27  of the spacer bodies  26  as shown in FIG.  1 . 
     Each spacer body  26  is formed of a pair of spacer halves  26 A,  26 B. Each of the spacer halves  26 A,  26 B provides respective flange portions  30 ,  31 . These flanges enable the spacer halves  26 A,  26 B to be bolted together using bolted connections B. 
     The outer surface  27  of spacer body  26  provides a plurality of projecting portions  34 . Each projecting portion  34  provides a drag surface  35  that engages the inner surface  14  of casing  11  as the assembly of flow lines  17 ,  21 , insulation layers  22 ,  23 ,  24 , and spacers  26  is pulled through annular containment space or bore  16  of casing  11 . The opposing ends  32 ,  33  of each spacer  26  provide respective male and female ends  32 ,  33  that connect to correspondingly shaped end portions of insulation members. 
     A second embodiment of the present invention provides a shell and foam insulation system that is shown in FIGS. 6-14 and that works in concert with the spacers  26  of FIGS.  1  and  3 - 5 . In FIGS. 6-7, and  13 - 14 , insulation member  28  includes a plurality of connected hollow shells  29  provided with a central bore  37  preferably preformed to the O.D. of the pipe it is to surround, in the case of I.D. insulation or cover (half shell) on O.D. covering. Once the complete plastic shell  29  is made in the proper I.D. and O.D. it is filled with polymeric foam  36  of the proper density. One determines the proper density of the foam  36  to be used by determining the K-value (insulation value) desired based on flowline operating temperature and outside temperature. K-value is an expression of heat transfer(BTU/FT2Hr° F.). The normal range for a pipe bundle is approximately 28 or lower. 
     For pressures up to 1500 PSI the shell  28  is preferably formed of High Density Polyethylene (HDPE). For pressures above that the shell can be formed of Nylon. The wall thickness on the shell  29  can be varied to compensate for pressure. 
     As water depth increases, the pressure on the insulation increases. The pressure in p.s.i. is approximately ½ of the water depth in feet(3,000 ft. below sea level=1,500 psi). This pressure can potentially cause insulation to compress, contort and/or crack. 
     A foam  36  encapsulating plastic shell  29  of HDPE (high density polyethylene), polypropylene or any engineering rosin, for extreme pressures, can be made to withstand pressures and keeps polyurethane foam  36  intact. 
     The foam encapsulating shell  29  is preferably preformed to the desired thickness, length and diameter in a half shell form, leaving PU foam fill holes (not shown) in one end. The form is filled with the applicable density foam  36  and the holes are plugged. For inside bundle use the preformed shell halves  29  are aligned around the pipe(s) with male projections and female grooves connecting as shown in FIGS. 6,  9 - 12 ,  14 . Bands (not shown) can be placed around the two halves  28 A,  28 B to form a complete shell insulation member  28 . 
     FIGS. 3,  4 ,  6 - 7 ,  13  and  14 , it can be seen that a pair of shell halves  28 A,  28 B assemble together at longitudinally extending mating faces  43 ,  44  of shell half  28 A that engage correspondingly shaped mating faces  45 ,  46  of shell half  28 B (see FIG.  7 ). The mating faces  43 ,  46  provide grooves  33  that form a connection with projecting portions  32  of the mating faces  44  and  45 . Thus, a tongue and groove type longitudinally extending connection is formed between an upper shell half  28 A and a lower shell half  28 B as shown in FIG.  7 . 
     The shell halves  28 A,  28 B also form connections end to end with other shell halves  28 A,  28 B and with spacers  26  as shown in FIGS. 6,  9 - 12  and  14 . In FIGS. 6 and 14, the male connecting end  41  of an assembled shell  28  (including halves  28 A,  28 B) forms a connection with a female connecting end  42  of the next insulation member  28 . A number of such insulation members  28  can be connected end to end as shown in FIGS. 11 and 12. 
     At intervals, a spacer  26  is placed in connection end-to-end with two insulation shell members  28 . In FIG. 14, the male connecting end  47  of spacer  26  forms a connection with the female connecting end  42  of shell  28 . Similarly, the female connecting end  48  of spacer  26  forms a connection with the male connecting end  41  of insulation member  28 . 
     For outside use on existing flowlines laid on the ocean bottom exposed, a preformed shell (see FIGS. 15-27) is made to fit the O.D. of the pipe to be insulated. The half shells are jointed to the desired length, by bolting sections together and installing bolts in the preformed holes in the end of each section. The proper weight is calculated needed to hold the half shell section on the bottom around the pipe and a concrete or similar half shell saddle is made to fit over the insulation section. 
     The embodiment of FIGS. 15-27 provides a pipe and insulation apparatus designated generally by the numeral  50  in FIGS. 15 and 24. Pipe and insulation apparatus  50  includes a frame  53  that carries insulation shell members  54 . The frame  53  and its carried insulation shell members  54  can be used to cover a pipeline  50  that is on the seabed  49 , even if the pipeline  51  is partially below mud line  52 . 
     Frame  53  provides a ballast pipe  55  having an interior ballast chamber  56 . A “pig” or seal member  86  can be provided in ballast tank  55  chamber  56  to ensure full emptying and full filling. Clamps  57 ,  58  can be bolted together for securing ballast pipe  55  to frame  53  at strut  62 . The frame  53  includes a U-shaped member  59  having opposed side walls  60 ,  61 . 
     The side wall  60  carries an appendage  63  that is longitudinally extending and generally triangularly shaped as shown in FIG.  18 . The appendage  63  includes a transverse plate member  64  and a diagonally extending plate member  65 . Similarly, an appendage  66  is carried by sidewall  61 . The appendage  66  includes plate member  67  and plate member  68 . Thus the appendage  66  is also generally triangularly shaped in transverse section. The appendages  63 ,  66  function to support insulation member  54  and position against U-shaped member  59  as shown in FIGS. 19 and 24. The diagonally extending plates  65 ,  68  form an angled surface that helps center frame  53  on pipe  51  as shown in FIG.  24 . Additionally, each of the appendages  63 ,  66  provides a pointed end portion  69 ,  70  respectively that engage the seabed  49  when the apparatus  50  is in operating position as shown in FIG.  24 . 
     In FIG. 17, insulation member  54  is in the form of a plastic, polymeric shell such as polyethylene or nylon. The shell  54  provides an outer shell member  71  that is curved in an inner curved shell member  72  that engages pipe  51 . A pair of flat shell surfaces  73 ,  74  are respectively positioned next to transverse plates  64 ,  67  of frame  53  as shown in FIG. 19 upon assembly. The shell  54  includes a plurality of stiffeners or baffles  75  that are radially extending and circumferentially spaced. A foam filler  36  is placed within and surrounded by the shell members  71 ,  72 ,  73 ,  74  as shown in FIG.  17 . This prevents pressure and the surrounding environment from accessing the foam  36  thus preventing its failure in use. Male and female end portions  97 ,  98  respectively enable a plurality of insulation members to be connected end to end, with the male end portion  97  engaging the female end portion  98  so that the overlapping joint between each member  54  insulates. 
     In FIGS. 20-27, the method of the present invention is shown in more detail. The completed pipeline is assembled on beach  76  and pulled into the marine environment using a boat  77  and towline  78  (see FIG.  20 ). At sea, a pair of boats  77 ,  79  tow the assembled apparatus  50  to a job site. A towline  78  extends between lead boat  77  and the front of apparatus  50  as shown in FIG.  21 . Similarly, a towline  80  connects the rear of the assembled apparatus  50  to a following boat  79 . Dimension A designates the spacing between vessels  77 ,  79 . 
     Dimension B in FIG. 21 indicates the distance between the water&#39;s surface  81  and the seabed  49 . Dimension C in FIG. 21 indicates the distance between the apparatus  50  and a pipe line  51  resting on seabed  49 . These distances can range to the distance from the water&#39;s surface a few feet below the water&#39;s surface for dimension“B” to the distance from seabed to a few feet above the seabed for dimension“C”. 
     A remotely operated vehicle  82  having camera  83  can be used to position the apparatus  50  directly above pipeline  51 . Flowlines  84  and  85  can be used to control ballast fluid as it is transmitted to or from ballast pipe  55 . FIG. 23 illustrates the lowering of the apparatus  50  onto pipeline  51  with the aid of remotely operated vehicle  82  and its camera  83 . 
     The apparatus  50  of the present invention can alternately be placed upon a submerged pipeline  51  using a lay barge  90 . Lay barge  90  is shown in FIGS. 25 and 26 secured to a desired location using anchor lines  92 . The apparatus of the present invention can be assembled on deck of the lay barge by pulling sections from supply barge  91  using booms  93 . A stinger  94  angles into the water for lowering the apparatus  50  into the ocean. 
     In FIG. 27, a section of the apparatus  50  is shown with ballast pipe  55  being clamped with clamp members  57 ,  58  with two frame  53 . At the leading end of an assembly of the pipe and insulation apparatus  50  of the present invention, there is provided a cover plate  95  having padeye  96  for forming a connection to either of the tow lines  78  or  80 . 
     The present invention allows for existing deep water pipelines that need additional insulation and/or weight to be insulated without the need for burying or other more costly alternatives to be installed. An optional radiant barrier (not shown) may be added to the I.D. and/or O.D. of the plastic shell lining. Insulation shells  28  can be joined longitudinally by welding, e.g. 
     The following table lists the parts numbers and parts descriptions as used herein and in the drawings attached hereto. 
     
       
         
               
             
               
               
               
             
           
               
                   
               
               
                 PARTS LIST 
               
             
          
           
               
                   
                 Part Number 
                 Description 
               
               
                   
                   
               
               
                   
                 10 
                 piping assembly 
               
               
                   
                 10A 
                 inner pipe assembly 
               
               
                   
                 11 
                 casing 
               
               
                   
                 12 
                 wall 
               
               
                   
                 13 
                 outer surface 
               
               
                   
                 14 
                 inner surface 
               
               
                   
                 15 
                 drag coating 
               
               
                   
                 16 
                 annular containment space 
               
               
                   
                 17 
                 product flow line 
               
               
                   
                 18 
                 flow bore 
               
               
                   
                 19 
                 wall 
               
               
                   
                 20 
                 outer surface 
               
               
                   
                 21 
                 product flow line 
               
               
                   
                 22 
                 insulation layer 
               
               
                   
                 23 
                 outer foil layer 
               
               
                   
                 24 
                 inner foil layer 
               
               
                   
                 25 
                 outer cylindrical surface 
               
               
                   
                 26 
                 spacer body 
               
               
                   
                 26A 
                 spacer half 
               
               
                   
                 26B 
                 spacer half 
               
               
                   
                 27 
                 outer cylindrical surface 
               
               
                   
                 28 
                 shell insulation member 
               
               
                   
                 28A 
                 shell half 
               
               
                   
                 28B 
                 shell half 
               
               
                   
                 29 
                 plastic shell 
               
               
                   
                 30 
                 flange 
               
               
                   
                 31 
                 flange 
               
               
                   
                 32 
                 projection 
               
               
                   
                 33 
                 groove 
               
               
                   
                 34 
                 projection 
               
               
                   
                 35 
                 drag surface 
               
               
                   
                 36 
                 foam 
               
               
                   
                 37 
                 weld cap 
               
               
                   
                 38 
                 payeye 
               
               
                   
                 39 
                 arrow 
               
               
                   
                 40 
                 arrow 
               
               
                   
                 41 
                 end 
               
               
                   
                 42 
                 end 
               
               
                   
                 43 
                 mating face 
               
               
                   
                 44 
                 mating face 
               
               
                   
                 45 
                 mating face 
               
               
                   
                 46 
                 mating face 
               
               
                   
                 47 
                 end 
               
               
                   
                 48 
                 end 
               
               
                   
                 49 
                 seabed 
               
               
                   
                 50 
                 pipe and insulation apparatus 
               
               
                   
                 51 
                 pipeline 
               
               
                   
                 52 
                 mudline 
               
               
                   
                 53 
                 frame 
               
               
                   
                 54 
                 insulation shell 
               
               
                   
                 55 
                 ballast pipe 
               
               
                   
                 56 
                 ballast chamber 
               
               
                   
                 57 
                 clamp 
               
               
                   
                 58 
                 clamp 
               
               
                   
                 59 
                 U-shaped member 
               
               
                   
                 60 
                 side wall 
               
               
                   
                 61 
                 side wall 
               
               
                   
                 62 
                 strut 
               
               
                   
                 63 
                 appendage 
               
               
                   
                 64 
                 transverse plate 
               
               
                   
                 65 
                 diagonal plate 
               
               
                   
                 66 
                 appendage 
               
               
                   
                 67 
                 transverse plate 
               
               
                   
                 68 
                 diagonal plate 
               
               
                   
                 69 
                 pointed edge 
               
               
                   
                 70 
                 pointed edge 
               
               
                   
                 71 
                 curved shell section 
               
               
                   
                 72 
                 curved shell section 
               
               
                   
                 73 
                 flat shell section 
               
               
                   
                 74 
                 flat shell section 
               
               
                   
                 75 
                 stiffener plate 
               
               
                   
                 76 
                 beach 
               
               
                   
                 77 
                 boat 
               
               
                   
                 78 
                 towline 
               
               
                   
                 79 
                 boat 
               
               
                   
                 80 
                 towline 
               
               
                   
                 81 
                 water surface 
               
               
                   
                 82 
                 remotely operated vehicle 
               
               
                   
                 83 
                 camera 
               
               
                   
                 84 
                 flowline 
               
               
                   
                 85 
                 flowline 
               
               
                   
                 86 
                 pig 
               
               
                   
                 90 
                 lay barge 
               
               
                   
                 91 
                 supply barge 
               
               
                   
                 92 
                 anchor line 
               
               
                   
                 93 
                 lifting boom 
               
               
                   
                 94 
                 stinger 
               
               
                   
                 95 
                 cover plate 
               
               
                   
                 96 
                 padeye 
               
               
                   
                 97 
                 end 
               
               
                   
                 98 
                 end 
               
               
                   
                 S 
                 side boom 
               
               
                   
                 W 
                 winch 
               
               
                   
                 C 
                 cable 
               
               
                   
                   
               
             
          
         
       
     
     the foregoing embodiments are presented by way of example only; the scope of the present invention is to be limited only by the following claims.