CA2377767A1

CA2377767A1 - Ensulated pipe

Info

Publication number: CA2377767A1
Application number: CA002377767A
Authority: CA
Inventors: F. Glenn Lively
Original assignee: Individual
Current assignee: Individual
Priority date: 1999-07-02
Filing date: 2000-06-30
Publication date: 2001-01-11
Also published as: US6397895B1; WO2001002503A1; EP1198526A1

Abstract

Pipes or pipelines insulated and optionally coated on their interior surface or surfaces are described. Pipes or pipelines insulated and optionally coate d on their exterior surface or surfaces are also contemplated. The pipes or pipelines may be for submerged service, below the surface of water. The insulation chosen may be an epoxy substantially free of phenolics and one or more of glass or ceramics. The coating may been an abrasion resistant coatin g. Such pipes or pipelines are generally intended for the transport of fluids, which can include natural gas, natural gas liquids, crude oil, refined products, chemicals, combinations thereof, and the like.

Description

PATENT APPLICATION
TTTLE: INSULATED PIPE
INVENTOR: F. GLENN LIVELY
TECHNICAL FIELD
This invention relates generally to pipe coating. More specifically, embodiments of this invention relate to insulation layer or layers on a pipe's . circumference, where such layers may be abrasion resistant, corrosion resistant and provide thermal insulation to the pipe's contents. The insulation may be placed on a pipe's exterior circumference or surface; interior circumference or surface, or both. The pipe or a pipeline including the pipe, is intended for use in fluid transport, generally submerged.
Description Introduction Embodiments of my invention concern certain pipe insulation and pipe coatings.
In embodiments of my invention, the insulation may be applied to the 2o interior circumference or surface of pipes or pipe lines, at least a first layer insulation may be applied to the pipe surface preceeded by an optional primer, and optionally at least a first layer of an abrasion resistant coating may be applied to the insulation.
In other embodiments of the present invention the insulation may be a Ceramic-CoverTM 100, (manufactured) Therma-Cote Inc. of Atlanta, Georgia, USA. and may be described as a viscous solution of ceramic and acrylic latex.
Or the insulation may be Therma-Coat from Hempel Coatings, Conroe, TX. The topcoat or abrasion resistant coating, EC-376F, may be manufactured by Industrial Environmental Coatings Corp of Pompano Beach, FL.
3o Embodiments of this invention further include certain methods of applying the insulation and the optional coating. Also contemplated are pipes and pipelines _7_ coated, on the interior circumference and/or surface, exterior circumference and/or surface, or both, with an optional primer, with the insulation and/or the abrasion resistant coating. The insulation and optional abrasion resistant coatings have properties rendering them superior to, and unique from, previously available s pipe insulation and coating. The pipe insulation and optional abrasion resistant coatings described herein are suited for use in producing certain classes of insulated, submerged pipes or pipelines. Those skilled in the art will appreciate that numerous modifications to these embodiments can be made without departing from the scope of the invention. For example, although gas and crude to oil pipes and pipelines, insulated on their interior, are exemplified herein, the insulated pipelines may be made using combinations of other coatings and other surfaces to be coated such as the exterior or a combination of exterior and interior surfaces. To the extent my description is specific, it is solely for the purpose of illustrating embodiments of my invention and should not be taken as limiting the 15 present invention to these embodiments.
Definition of Terms and Tests:
Density: ASTM D-793 Compressive Strength: ASTM D-1621 R value, Thermal Resistance ASTM C-177-85 2o k, Thermal Conductance ASTM C-158 Adhesion to Steel ASTM D-4541 Primer A water and chemical resistant primer may optionally be applied directly to the steel surface of the pipe being insulated, between the pipe and a first layer 2s of insulation. When a pipeline is installed offshore on the seafloor it may have high spots and low spots due to the undulation of the seafloor. In the low spots water may accumulate on the interior of the pipe. This water may come from hydrostatic testing of the pipeline or water entrained in the fluids carned by the pipeline. Such water may cause corrosion, called "6 o'clock" corrosion, for its 30 location on the bottom of a pipeline as one would view a cross section.
Should water penetrate the layers of insulation and the topcoat on the interior of the pipe, -, it could cause corrosion, resulting perhaps in a leak. Particularly troublesome is the presence of carbonic acid or hydrochloric acid in the water. Occasionally oil and gas will contain small amounts of corrosive gases such as carbon dioxide or hydrogen sulfide. When either of these gases are dissolved in water, acid is s created that may attack the steel surface of the pipe causing failure of the pipe.
The use of a primer between an insulation layer and the steel pipe surface may mitigate such a problem. Many types of primers are available and will be known to those of ordinary skill in the art, one type is a phenolic primer such as EP-10, which is manufactured by Morton (Reading, PA). This primer may be applied at to a thickness that may average 1 mil and may be cured in an oven at 300°F for one hour. Other primers may be used, some of these primers may not require oven curing, but may be air cured.
Insulation In embodiments of the present invention, the insulation may be a Ceramic-15 CoverTM 100 (CC-100), manufactured Therma-Cote Inc. of Atlanta, Georgia, USA, or the insulation may be Therma-Coat coating manufactured by Hempel Coatings, referred to above. Polyurethane foam (PU), may have a heat or thermal conductance (k) from 0.65 to 0.1 BTLJ/sq. ft., hr., F°. The conductance of the insulation of embodiments of my invention will be <_ 0.4 BTU/sq. ft. hr F°, or <_ 20 0.3 BTU/sq. ft. hr F°, or <_ 0.08 BTU/sq. ft. hr F°, or <_ 0.07 BTU/sq. ft. hr F°, or _<
0.06 BTU/sq. ft. hr F°, or _< 0.05 BTU/sq. ft. hr F°, or <_ 0.04 BTIJ/sq. ft. hr F°, or <_ 0.03 BTU/sq. ft. hr F°, or <_ 0.02 BTU/sq. ft. hr F°, or >_ 0.001 BTU/sq. ft. hr F°, or >_ 0.003 BTU/sq. ft. hr F°, or >_ 0.005 BTU/sq. ft. hr F°. The density of the insulation, as determined by ASTM D-792, may be >_ 0.1 g/cm3, or >_ 0.2 g/cm3, 25 or >_ 0.3 gicm3, or >_ 0.35g/cm', or <_ 0.95 g/cm', or <_ 0.75 g/cm~, or <_ 0.65 g/cm' or <_ 0.55 g/cm3. The density of common rigid urethane foams is in the range of 0.012 - 0.025 g/cm3. The compressive strength of the insulation of embodiments of my invention, may be >_ 100 psi, or >_ 200 psi, or >_ 400 psi , or >_ 800 psi, or >_ 1500 psi, or >_ 2,000 psi , or >_ 2500 psi or >_ 3000 psi, or >_ 3500 psi, or >_ 4000 psi.

The compressive strength of rigid urethane foams is in the range of 15-60 psi ( 10% deflection).
The insulation may be characterized by its R value (Thermal resistance °F
hr ft'' BTU) per applied inch. Other types of insulation typically have Thermal resistance as follows: cork board typically has an insulation value of about 3.33 R
value per inch; rock cork about 3.9 R value per inch; expanded polystyrene about 3.0 R value per inch; and polyurethane foam 5-9 R value per inch. The insulation of embodiments of the present invention may be >_ 5 R value per inch, or >_ 10 R
value per inch, or >_ 12, or >_ 14 R value per inch, or >_ 25 R value per inch, or >_ 35 to R value per inch, or >_ 40 R value per inch, or >_ 45 R value per inch, or >_ 50 R
value per inch, or >_ 60 R value per inch or <_ 400 R value per inch, or <_ value per inch, or <_ 200 R value per inch, or <_ 150 R value per inch, or <_ value per inch. Other insulation is contemplated as long as it provides the insulation values stated herein.
Adhesion to steel, of the insulation of embodiments of my invention, as determined by ASTM D-4541, may be >_ 1000 psi, or >_ 1500 psi, or ? 1700 psi, or >_ 1800 psi, or >_ 2000 psi, or >_ 2200 psi, or >_ 2300 psi.
The CC-100 insulation is described by its manufacturer (Therma-Cote) as a proprietary viscous solution of ceramic and acrylic latex. The insulation is also 2o described as an 84% solid latex, high density material. The ceramic portion of the CC-100 insulation is described as an asymmetrical particle, of amorphous shape.
Such a shape is substantially non-spheroidal. However, I also contemplate spheres or sphereoidal shapes for the ceramic portion insulation. The insulation may also contain glass microspheres. The ceramic or glass portion of the CC-100 insulation will be >_ 5% (volume), or >_ 7%, or >_ 9%, or <_ 25%, or <_ 20%, or <_ 15%.
These volumetric measurements are after substantially all of the volatiles and/or evaporative ingredients have been removed.
The Therma-Coat insulation is characterized by its manufacturer (Hempel) as a high solids epoxy, 84+% solids (volume) and/or 86+% solids by weight. The 3o Therma-Coat insulation is substantially free of phenolics. By substantially free of phenolics, I intend that <_ 5 weight percent, or <_ 3 weight percent, or <_ 1 weight percent, or 0 percent of the high solids epoxy will be phenolics. This substantial freedom of phenolics relates to the insulation of embodiments of my invention and not to the optional primer or optional top coat, which may include phenolics.
The Therma-Coat (Hempel) insulation may use microspheres of glass, ceramic spheres, amorphous ceramic or glass shapes, spheroidal ceramic or glass shapes, non-spheroidal ceramic or glass shapes, or combinations thereof. The ratio of glass to ceramics in the organic matrix, after volatilization and or evaporation may be 10:90 to 90:10 or 20:80 to 80:20, or 30:70 to 70:30, or 40:60 to 60:40. The ratio t o of both glass and ceramic to the organic components, after volatilization and/or evaporation may be 10:90 to 90:10, or 20:80 to 80:20, or 30:70 to 70:30, or 40:60 to 60:40. The insulation may be applied by any conventional method, such as rolling, brushing, troweling, or spraying. In a typical installation, the insulation will be applied to the interior surface or circumference of the pipe, the exterior surface or circumference of the pipe, or both. Optionally, a primer will be placed directly on the pipe surface or surfaces, followed by the insulation described herein.
While the manufacturers of these products state that no specific surface preparation may be necessary, the surface may be prepared, by methods known to 2o those of skill in the art, to reduce or eliminate any oils, dirt, or other potential contaminants on a pipe's surface or surfaces, that might affect the adhesion or insulation performance of the applied combination of insulation and abrasion resistant coating.
In application of this insulation to a pipe, after optional surface preparation, and after an optional primer layer or layers applied and the insulation applied, an optional abrasion resistant coating be applied after the insulation layer or layers have cured.
The surface roughness or smoothness of steel pipes is generally 0.0018 inches, while the insulation described here in is generally <_ 0.0006 inches, or <_ 0.0004 inches, or <_ 0.0002 inches, or _< 0.0001 inches, or <_0.00009 inches.
the insulation will also provide corrosion protection to the surface or surfaces to which it is applied.
The surface temperature of the pipe upon which the insulation may be ambient or up to 150°F. Application in the range of from 32°F to 460°F is also s contemplated.
Applications of the insulation may be at a total thickness of >_ 2 mils, or _>
5mils, or >_ 10 mils, or >_ 20mils, or >_ 25 mils, or <_100 mils, or <_ 90 mils or <_ 85 mils. Or in other embodiments of my invention, the insulation can be applied in one coat at >_ 2 mils or >_ 5 mils, or >_ 10 mils or >_ 15 mils, or >_ 25 mils, or <_ 60 to mils, or <_ 50 mils or <_ 40 mils thickness, or in several coats or layers, 2, 3, 4, 5, 6, 7. 8, 9, 10 or more layers, to these total thicknesses. The layers may be the same thickness or different.
Another insulating material that may be used is a product known as Super-Therm~. Super-Therm is a ceramic coating that is said to utilize three types 15 ceramic particles to achieve results. Two of the ceramics are said to reflect heat and the third is said to prevent heat Ioss by conduction. It is said by the manufacturer to be made with two acrylics and one urethane. It completely cures in 7-10 days and may be applied within a temperature range of 40°F up to 110°F.
Hot Box Testing indicates that this material to be a thermal resistor that is said to 2o be as effective as fiberglass with an equivalent rating of R19 (per inch).
Thermal Conductivity of this material has been tested with a reported range from 0.00543 watts/cm °K up to 0.00640 watts/cm °K. Insulation coefficients are reported by the manufacturer to be 0.13 BTU/ft2 hr F° or in metric terms-- 0.019 metric watts/meter kelvin°~
25 Another insulation product that may also be used where the insulation value is provided by hollow glass (micro)spheres. This product is called Biotherm~ 453 and is manufactured by TFT of Houston, TX. This material is said by its manufacturer to be a primarily epoxy resin with proprietary polyamines. It is further said to have low volatile organic compounds (VOC's) 3o and is normally trowel applied but may be spray applied.

-7_ The use of the insulation layer or layers, without the use of a topcoat, is also contemplated, such insulation-only applications may include the optional pnmer.
Abrasion Resistant Coating Optionally, one or more layers of a topcoat, such as EC-376F, manufactured by Industrial Environmental Coatings Corp of Pompano Beach, FL, may be used as the topcoat or abrasion resistant coating, generally applied to the insulation layer or layers.
EC-376F is described by the manufacturer to be a specially formulated 1 o high performance. 100% solids, flexibilized epoxy phenolic that is said to demonstrate excellent adhesion, resistance to thermal and mechanical shock and excellent chemical and physical resistance in a wide range of crude and refined petroleum products. It is further described as a thick-film epoxy material that exhibits excellent performance characteristics when evaluated against other thick-film epoxy coatings in tthe following tests:
*Standard Atlas Cell Test (Modified NACE TMO 174-91 ) *Pressurized Atlas Cell Test (Modified NACE TMO 174-91 ) *Autoclave Test (MACE TMO 1 85-88) *Impact Test (ASTM G 14-88) *Abrasion Resistance (ASTM D 4060-90) *Cathodic Disbondment (ASTM G95) *Adhesion Pull-Off Strength (ASTM D4541-89) *Flexibility (Modified CSA 2245, 20-M92) *Hardness (Shore D) *Electrochemical Impedance Spectroscopy (E.LS.) Epoxy coatings generally may not be suited for high temperatures (above 225°F). Epoxy coatings may be generally low in adhesion (900-1000 psi to the substrate) where EC-376 has tested above 1800 psi. EC-376 exhibits improved permeability values over typical epoxy coatings. The chemical resistance of 3o epoxy is generally good but depends on the type epoxy used.

_g_ Additionally or alternatively, the optionai abrasion resistant coating may be Ceram-KoteTM 54, manufactured by Freecom, Inc. Big Spring, Texas, USA, which is described as an epoxy ceramic. The coating is described as an epoxy ceramic. The product may be considered to be described in US 4,968,538 and 4,789,567, both fully incorporated by reference herein for purposes of US
patent pracrice.
The optional abrasion resistant coating can be applied to the insulation in l, or 2, or 3 or 4 or more layers at a thickness of >_1 mils, or >_ 5 mils, or >_ 10 mils, or _< 40 mils, or <_ 30 mils, or _< 25 mils, or <_ 20mils, or <_ 15 mils. The 1o number of coats or layers of this abrasion resistant coating material, as for the above insulation, may be more than one, and up to 10 or more.
Other optional top coats are contemplated. As long as the coating selected has substantially complete adhesion to the insulation, provides a desired protection of the insulation layer or layers, if necessary, and does not substantially ~ 5 impede the flow of product and may enhance the flow, they will be among the coatings contemplated.
Pipes and Pipelines Pipes and pipelines are contemplated as substrates to be coated by the combination of insulation and optional abrasion resistant coating. While generally 2o including pipes of >_ 2 inches (5 cm), or <_ 48 inches (232.2 cm), or <_ 40 inches, or <_ 30 inches (75 cm) in inside diameter ()D), other sizes are contemplated as well. The pipe will generally form some portion of a fluid delivery apparatus, such as a pipeline, including pumps, manifolds, heaters and the like. Pipe may be of any length, and when combined through conventional means (welding, 25 coupling), may form a pipeline, again of any length. The pipelines contemplated are used to transport fluids such as natural gas, crude oil, refined petroleum products (such as gasoline, jet fuel, aviation gas, kerosene, heating oil, or bunker oil) fluid chemicals, slurries, brine, and the like. While an environment for the coated and insulated pipe or pipeline may be underwater, other uses are not 3o precluded, such as underground, or above ground in any application where maintanence of some or all of a temperature difference (0T) between product inside the pipe and the exterior environment is sought.
In a further embodiment, at least a portion of the pipeline is submerged in water. The water may be fresh, brackish or salt water. The depth may be 0.1 meter to 2 kilometers or even greater depths as technology is available. are contemplated.
The combination of insulation and optional abrasion resistant coatings as described above may be of any total thickness, controlled by the application process and the desired control of product temperature and the environment that to surrounds the pipe or pipeline. The optional abrasion resistant coating is described above, and each layer may be applied in one or more coating passes or application layers. The amount of protection from the outside elements desired may be a consideration of the amount of insulation and or coating applied, the temperature and chemical makeup of the fluids to be transported, as well as the distance to be is transported. For instance product, e.g. crude oil, at 120°F as received from the wellhead, knowing the desired exit temperature traveling through water at 50°F, for two miles, will require certain levels of insulation, and the insulation may require a certain level of the optional abrasion resistant coating, both may be determined by those of ordinary skill in the art applying principles of fluid 2o transport and thermodynamics. Also to be considered is the nature of the transported fluid, for instance, if the product has a substantial portion of constituents that would crystallize (or form hydrates) or in another way come out of the fluid at temperatures below the temperatures coming out of the wellhead, then the product must be desireably kept above the temperature at which the 25 crystallization would occur. Even if the product is substantially devoid of such constituents, but would rise in viscosity at temperatures approaching that of the (lower) ambient environment, it is advantageous to reduce or eliminate the viscosity rise. There may be other reasons or combinations of reasons to insulate pipes and pipelines, such uses are also contemplated.
3o Those of ordinary skill in the art will appreciate that an effective amount of each of the insulation and the optional abrasion resistant coating layer or layers will be applied to a given pipe for specific service. Again, as above, the temperature difference between the enviromnent and the fluid product (eg water temperature, and crude oil temperatwe) as well as the temperature at which the fluid product is desired to be maintained or delivered, will be determanitive of the amount of insulation, thickness and/or number of insulation layers, and optional abrasion resistant coating used. By an effective amount I intend that this include not only total thickness, but also an effective number of layers making up the total thickness. The layers may be equal or unequal in their thickness.
Fluids to While natural gas, natural gas liquids, and crude oil are disclosed, any fluid, e.g. gas, liquid, slurry, are contemplated.
Other Pipeline Insulation While the insulation described herein will generally suffice for relatively long pipe runs and in water that can be cold, additional insulation schemes may be l5 used in addition to the insulation on the interior of the pipe disclosed herein.
For instance, burial in a trench and/or burial or partial burial with fine-grained bulk material such as sand, and/or coarse-grained material such as gravel as an addition to embodiments of my invention is also contemplated. Among such techniques are those disclosed in GB 2 221 873A (Wesminster Seaway Ans).
2o Other techniques such as pipe in a pipe, while generally being less desirable as a sole insulation system than the insulation system discussed herein, may be used in addition to the disclosed insulation.
In other embodiments of my invention, insulation of the pipeline will be accomplished substantially completely with the insulation described herein. By 25 substantially completely I intend that >_ 95% , or >_ 97%, or >_ 99%, or 100%, of the insulation of a pipeline will come from the insulation of embodiments discussed herein. Some insulation value may result from the optional abrasion resistant coating, the majority of the insulation value is expected to be derived from the insulation of embodiments of my invention.
3o In another embodiment the pipe insulation will be substantially free of polyurethane (PIE foam, polyvinyl chloride (PVC) foam, polystyrene foam (PS) or combinations thereof. By substantially free, I intend that <_ 10%, <_ 5%, <_ 2%, or 0% PU, PVC or PS, will be present in or on the pipe, either on its exterior or its intenor.
In yet another embodiment, the interior of the pipe will be substantially s free of PU, PVC, or PS foam (0%), while the exterior may be insulated with PU, PVC, or PS foam or a composite of PU, PVC, or PS foam and other polymeric, bituminous or cementitious materials.
In further embodiments, I contemplate that the pipe, insulated on its interior by insulation discussed herein, will be substantially free of insulation on to its exterior. By substantially free, I intend <_ 5%, <_ 2%, or 0% of any exterior coating will be made up of any material referred by those of skill in the art as insulation.
In another embodiment, the exterior of the pipe may be protected from corrosion or physical damage by a coating, which may be a polymeric coating.
15 Such coating should not add more than 20%, or not more than 10%, or not more than 5% to the total insulation value of the pipe, the preponderance of the remainder of the insulation value to be provided by the insulation discussed herein. Such corrosion protection will generally be located on a pipe's exterior, but is not so limited.
2o While I contemplate pipes or piplines with the insulation proximate the inside circumference of the pipe or pipeline (and optionally a primer between the pipe surface and a first layer of insulation), and the optional abrasion resistant coating proximate the inside circumference of the insulation layer or layers, other schemes are also contemplated. For instance, a layer of insulation may be formed 25 on the inside circumference of a pipe or pipeline, while the abrasion resistant coating may be on the exterior circumference of the pipe. As possible combinations described below a) = insulation layer, b) = abrasion resistant coating, Pi) = pipe's interior circumference, Po) = pipe's exterior circumference, and r1= a number 2 or greater.
3o Pi, a, b, or Pi, b, a, or Pi, a, b, a, or Pi,a,a,..a'',b,b,...b~' Or,Pi,a,a,..a~',b,or Pi,a,b,a,bor b, a, Po, Pi, a, b or a, Po, Pi, a, b, or a, a, ... a'~, Po, Pi, a, a, ... an, b, or b, Po, Pi, a, b, or b, ... b'', a, ... a~', Po, Pi, a, ... a~', b, s ... b~' or Po, Pi, b~', a~', or b, b, a,a, Po, Pi, or b, a, a, Po, Pi or b~', a'', Po, Pi, a'', b~', or b, Po, Pi, or b~', Po, Pi, or a, Po, Pi, a or a, Po, Pi, a~', or a~', Po, Pi, a, or a~', Po, Pi, a''. , Po, Pi, a, or Po, Pi, a''.
Other methods of insulating pipe or pipelines known to those of skill in the t o art may be used in conjunction with the with the insulation on the interior of the pipe as disclosed herein. Such other methods should be additive to the techniques and materials (insulation) disclosed herein. At a minimum such techniques should not detract from the insulation provided by the insulation described herein.
Exterior Pure Coatings 15 While my disclosed insulation and optional abrasion resistant coatings may be formed on the interior surface of the pipe, these or other coatings may be applied to the exterior surface of the pipe.
Corrosion protection of an exterior surface of a pipe by any conventional means known to those of skill in the art, in addition to my disclosed insulation and 20 optional abrasion resistant coating on the interior and optionally on the exterior of the pipe, is also contemplated.
Such exterior corrosion protection may include, but is not limited to, adhesive and tape (e.g. vinyl or polyethylene) wrapping, epoxy powder coating, other powder coating, extruded plastic (such as polyurethane, polyolefins, vinyl 25 and the like), extruded elastomers (ethylene propylene rubber, butyl rubber, nitrite rubber, polychloroprene rubber and the like) and combinations of these techniques.
Additionally, the application of the insulation layer or layers, preceded by an optional primer, and optionally covered by an abrasion resistant coating, to the 3o exterior of the pipe, in addition to the application of a similar system on the interior surface of the pipe is also contemplated.

Also contemplated are cement or cementitious compositions used on the exterior of pipes or pipelines in conjunction with embodiments of my invention disclosed herein.
Pipe Joining and Joint Protection As pipe is joined by welding, coatings formed on the interior surface of the pipe prior to welding, may be degraded by the high temperature of welding. To address such a problem, various measures have been proposed. Among these various measures are US 5,547,228 and a Continuation-in-Part of the '228 document, US 5,566,984, both fully incorporated by reference herein for purposes of U. S. patent prosecution, which suggest a solution. These documents suggest several constructions that are said to protect both the pipe being welded and its coating. The cylindrical corrosion barrier for pipe connections may be a non metallic material such as polytetrafluoro ethylene (PTFE) which may also have fibers in the polymer matrix (such as glass fibers). Use of such welding protection devices and methods, in conjunction with embodiments of my invention, are also contemplated. We further contemplate that such a cylindrical corrosion barrier may be a length of pipe, similar in size and configuration (although small enough to fit in the pipes to be welded) to the PTFE barrier, and such small length of pipe may be coated similarly to the pipe itself by methods and with materials disclosed 2o herein. That is, on its interior, an optional primer may be proximate the interior surface of the barrier covered with at least one layer of the insulation and optionally at least one layer of an abrasion resistant coating. Such a system will provide insulation at the weld lines where the pipe is joined.
Additional insulating layers of other materials such as polyurethane, 2s polyvinyl chloride (PVC), polystyrene and the like, either foamed or non-foamed are also contemplated.
Other corrosion resistant coating or layers are also contemplated including, but not limited to asphaltics, pressure sensitive adhesives, PVC, polyethylene, impregnated paper and the like.
3o Prospective Examples Prospective Example 1 A 6 inch ( 15.24 cm) ID steel pipe is sand blasted with garnet to clean mill scale, dirt, grease and other contaminants from the steel. The grit so blasted on the interior surface creates a I-4 mil anchor profile to aid in adhesion of the primer and/or insulation layer to the interior steel surface of the pipe. A primer such as EP-10, manufactured by Morton, (Reading, PA), is applied at a thickness from 0.5 mil to 1 mil and is cured by heat for 30 minutes to one hour at 300°F.
The primer is applied directly to grit blasted steel surface prior to the application of the first insulation layer. The primer is spray applied using an automated coating lance that reaches from the entry end of the pipe to the far end. When the retraction of the to lance begins, the primer is applied by pressure through a spray tip on the end of the lance at 360 degrees to cover the interior surface at the thickness stated above.
The pipe is heated to a steel temperature of 150°F. A coating lance is inserted through the pipe and 40 mils of insulation Ceram Cover~ 100 is applied using an airless spray tip that spins creating a 360° spray pattern. The density of the insulation, as determined by ASTM D-792 is 0.41 g/cm3.
The pipe is then moved to a cure oven with a temperature of 160°F -175°F, and remains in the oven at the temperature for 10 minutes. Then a coat of Enviroline ~ EC-376 (Enviromental Coatings Corp., Pompano Beach FL) is applied to an additional (in addition to the thicknesses of insulation) thickness of 10 to 15 mils. After the abrasion resistant epoxy coating or top coating is applied and allowed to cure for 1 hour, a wet sponge holiday detection lance is inserted into the pipe which detects holidays or pinholes. If a pinhole is detected, the coating lance is re-inserted to that portion or portions where the pinhole is detected and additional abrasion resistant epoxy coating is applied.
Additional prospective examples are made to demostrate the effectiveness of the application of mufti-layers of the insulation. The examples represented in Tables II and IV are two different applications of insulation, and Table V
represents bare steel with no coating, primer, or insulation.
This comparison is between a steel pipe insulated with 40 mils of the 3o insulation in one layer (Table IV), and a similar steel pipe insulated with 40 mils of the insulation but with four ten mil layers (Table II). The assumptions, conditions and results are found in Tables I-IV.
All examples have an initial oil temperature of 140°F and are operating in an environment of 36°F water. The pipe is 6 inch. With one layer of insulation at 40 mils thickness at a flow rate of 10,000 barrels per day (bbl/day), the oil comes to 100°F in a distance of 4.56 miles. In the example with four ten mil layers (total again 40 mils) of insulation the oil does not come to 100°F until 17.11 miles, an increase over the single layer of 40 mils of over 275%. Also by contrast, the uninsulated (bare steel pipe, Table V) pipe comes to 100° F at (1.5 miles).
t o In the tables which follow, the following abbreviations are used:
Outside diameter Inside diameter d~
cross sectional area A
Heat flow from oil through (insulated) pipe, in BTIJ/hr.
p/1, Pipeline T° F Temperature, degrees Fahrenheit Ti Temperature inside of pipe/insulation To Temperature on outside of pipe Conclusion The present invention has been described in considerable detail with reference to certain versions thereof, other versions are possible. For example, while steel pipes insulated on their interior circumference for transport of hydrocarbons have been exemplified, other uses are also contemplated.
Therefore, the spirit and scope of the appended claims should not be limited to the description of the versions contained herein.

Table I
Oil Flow in Pipeline Pipeline: 6" Oil-steel 5 Btu/82.
film hr. F
conductance.
Uo-s d: 6.625 inchesWater-steel 4 Btu/ft2, conductance, hr. F
Us-w d;: 5.761 inchesSteel 312 Btu/ft2, thermal hr, F/in conductivity.
ks Length: 8 miles Oil 0.5 Btu/Lb, specific F
heat:
Ho X-sect. Area: 0.1810186 To, Ft2 temperature of oil Outer Surf. Area. 1.7344209 Tw, S: Ft2/Ft temperature of water Fluid: 40 API Fluid 0.181Ft3 (6.87 volume Lb/gal) Flowrate: 10000 BBL/Day 1.354gallon (38.99287 Ft3/min) Fluid Velocity: 215.40812 Weight w Ft/min Flow Transit Time: 3.2682148 Hours Wt. Of I-Ft. Section9.3021101 of Lb Oil:

Oil Temp. ~ Entrv: 140F

Outside Water Temp:36F

Internally CC Coated:4 layers CC-Oil 5 Btu/ft2, film hr, F
conductance, Ucc-o 10 mils Steel-CC 3.83Btu/ft2, each conductance, hr, F
US-cc CC-CC 0.667Btu/ft2, layer hr, F
conductance, Ucc Diameters 5.741 d4 CC 0.064Btu/ft2, (19' thermal hr, F/in conductivity, kcc layer) 5.721 d3 (2"

layer) 5.701 d2 (3' layer) 5.681 dl (4m layer) X-sect. Area: 0.1760261 Ft2 Fluid Velocity wICC:221.5176 Ft/min Flow Transit Time: 3.1780771 Hours Wt. Of 1-Ft. Sect. 9.045557 Of Oil: Lb Where q = S
x -twl -d I ~ d; d 1 1 ~ ~ ~ 1 1 -+ loge- + - ~ loge +
x -+ -+ + U
- +

2 x ~ ~' at d, U~ 2 x ka g dl Ua jjw-g dz d3 d4 the time required l temperature for oi to drop 10F ~T
x q =
w x Ho x 10F

- l 7-Table II
CC Coated Pipe Output Results Oil Flow in Pipeline 4 Layers of CC
(Total thickness of 40 mils) to mils/layer I o,ooo BOPD
q = 0.3225" (Ti-To) Avg. q Time Cum Distance T ~ q @ for for Time In P/L
F ~ T Temp DropTemp Hr Miles Btu/Hr Btu/Hr Drop Hr _____-14033.5412_ ______________-_________________________________________ _ _ _ _ 31.9286_ ____ _ 1.4165__ 3.5657 x __ _________1.4165_ ~
130 30.3161 _ _ _ _____ _ _1.5757-____2.9922_____-___ __________ 28.7035_ _ _ 7.5321_ 120 27.0909 ~

_ _ _ ______--_1.7751-_----_4.7674_ -_--_._ 110 _ 25.4784_ _ 12.0006 ~ 23.8658 ~ I

_ _ _ -_-_-_ 2.0324 6.7998 17.1167 _-----__ 22.2533 ___________________________________' 100 ~ 20.6407______________ _____________________ ________________________________ _________2.3769__-- _ ----___23.0999 90 17.415619.0282_ _ 9.1767 _ _ _ _ _ ______ 2.8620 -- 12.0386_ _ _ __________ 15.8030 ____________________ ______________-- 30.3042 80 14.1905 _ ___ _________ _______________________________________________ _______3.5958_ --15.6344_ _---__-39.3557 70 0.9654 2.5779_ _ _ _ _ _ _ ______ 4.8357 _--20.4702---____51.5284 __________ _ ____________________ ______________ _________ 60 _ 9.3528 __ 7.7403 _____ _________________________________________7.3809 _-_27.8510--___--70.1078 50 4.5152 6.1277 ____________________ ______________ ____________ _____ __________________________________________--_____1_5.5818_.-43.4328_____--40 1.2900 2.9026_ _ _ 109.3311 _ ________ _ __---________ ___-52.7819_ ---__ _ ____ 0.9675_ 9.3491 _ 132.8850_ 38 0.6450 _ -_ _ _ _______28.0473 ___80.8292__--_ ___________ 0.3225 203.4669 36 0.0000 Table III
Oil Flow in Pipeline Pipeline: 8", scheduleOil-steel film 5 Btu/ft2.
80 conductance. hr. F
Uo-s OD: 6.625 inchesWater-steel conductance,4 Btu/ft2, Us-w hr, F

ID: 5.761 inchesSteel thermal .12 Btu/ft2, conductivih~. hr. F/in ks Length: 8 miles Oil specific heat:.5 Btu/Lb, Ho 0 F

X-sect. Area:0.1810186 Ft2 Outer Surf 1.7344209 Area: Ft2/Ft Fluid: 40 API (6.87 Lb/gal) Flowrate: 10000 BBL/Day (38.99287 Ft3/min) Fluid Velocity:215.40812 Fdmin Flow Transit3.2682148 Time: Hours Wt. Of 1-Ft.9.3021101 Section Lb of Oil:

Oil Temp. 140F
~ Entn~:

Outside Water36F
Temp:

CC Coated: 1 layers CC-Oil film conductance,5 Btu/ft2, Interrtallv Ucc-o hr, F

_ 40 mils Steel-CC conductance.3.83 Btu/ft2.
each US-cc hr, F

CC-CC layer conductance,0.667Btu/ft2, Ucc hr, F

5.681 dl CC thermal conductivity,0.064Btu/ft2, ( 1~' layer)kcc hr, F/in X-sect. Area:0.1760261 Ft2 Fluid Velocity221.5176 w/CC: Ft/min Flow Transit3.1780771 Time: Hours Wt. Of 1-Ft.9.045557 Sect. Of Lb Oil:

Erternally 1 layers CC-Water film 5 Btu/ft2, CC Coated: conductance, hr, F

Ucc-w 20 mils (Estimated) each 6.665 d3 (outer layer OD) Outer Surf 1.74489029 Area: Ft2/Ft Table IV
Internal CC Coated Pipe Output Results Oil Flow in Pipeline One Layer of CC
4o mils/layer lo,ooo BOPD
q = 1.2082" (Ti-To) Avg. q Time for Cum Distance T q @ T for I Time In P/L
F Btu/Hr Temp DropTemp Drop Hr Miles Btu/Hr ~
Hr ______________ _______________________________________________________________________ 125.6535_ _ ______ _ __________________.___ _ _ _ -____ __ _______ 0.3781 _0.3781 ______0.9518.
_ _ 119.6124 _ _ 130 _ _ 113.5714 _ _ _ _ _______ 2.0106 __________ _______ __ 0.7987 I
120 4893 107.5304 _ _____ I 101 0.4206_ I____________. ___________ _______ _ _______ 110 _________________95.4483_ ___________ _______ 3.2034_1 89.4073 _ 0.4738_ _ 1.2726 _ _ _ _ ________ ________0.5425__ ______1.8151_______4.5690_ ____ ______ 83.3662 _ 00 77.3252 i _ _ _ ______ _ _________ _____ ______ _ ______ 71.2842_ 0.6345_ 2.4496 6.1661 ____ 65.2431 ' _ _______ _ _ ________0.7640__ _____ _____ 80 ______ _ _____ 3.2135 8.0892 53.1611 59.2021_ _ _ _ _ __ _ ____ _ ____, _____10.5054 ____________ _ ____ ____0.9598_4.1734 70 41.0790 47.1201_ _ _____ _ _ ______ _ _________1.2908__ _____ _ ___13.7547 _ ______ 35.0380_ 5.4642 1 60 28.9970 1 _ _ _ _______ _ ________1.9702__ ______7.4344_____18.7142 _____ ___ __ __ _ 50 6.9149 22.9559_ _ _ _ _ ________ ________4.1593__ ____11.5937______29.1842 _________ 0.8739_ 40 _ 1 __ 4.8328 _ _ _ 2.4956 14.0893 35.4662 _____ _______ _ _____________________________________________________________ 38 2.4164 3.6246 __________ _______________________________________________ ____21.5760___54.3122_ _____ ______0.0000________ 7.4868 36 1.2082 Table V
Bare Steel Output Results Oil Flow in Pipeline 10,000 BOPD
Avg. q Time for Cum Distance T q @ T for ~ Time in F Btu/Hr Temp Drop Temp DropHr P/L Miles Btu/Hr Hr' 140 374.6373 130 338.6145 356.6259 0.1304 0.1304 0.3192 120 302.5917 320.6031 0.1451 0.2755 0.6744 110 266.5889 284.5803 0.1634 0.4389 1.0744 100 230.5460 248.5575 0.1871 0.6260 1.5325 90 194.5232 212.5346 0.2188 0.8449 2.0681 80 158.5004 176.5118 0.2635 1.1084 2.7131 70 122.4776 140.4890 0.3311 1.4394 3.5235 60 86.4548 104.4662 0.4452 1.8847 4.6133 I

50 50.4319 68.4434 0.6795 2.5642 6.2767 40 14.4091 32.4205 1.4346 3.9988 9.7884 38 7.2046 10.8068 0.8608 4.8596 11.8954 36 0.0000 3.6023 2.5823 7.4419 18.2163 I

I

Claims

I Claim:

1. A submerged pipeline insulated on its interior for retaining the naturally occurring temperature of oil, where the pipeline is submerged in water at least 20°F lower in temperature than an initial temperature of said oil, comprising, a) a pipe;
b) at least two insulation layers formed on the inside circumference of said pipe portion of said pipeline, said insulation including one of glass microspheres, ceramics and combinations thereof, and an epoxy wherein said epoxy is substantially free of phenolics, wherein said insulation has an R value of one of >= 14 or <= 60 per inch, as determined by ASTM C 177-85, wherein the compressive strength of said ceramic insulation is >= 3500 psi, as determined by ASTM D-1621, and wherein said insulation layers are present on said inside circumference of said pipe at a total of one of >= 25 mils or <=
60 mils, said at least two layers being one of the same thickness or different thicknesses;
c) optionally, at least one abrasion resistant layer formed on the inside circumference of said insulation, said optional abrasion resistant layer, if present, is present at one of >= 5 or <= 15 mils.

2. An abrasion resistant, corrosion resistant, insulated pipe comprising:
a) optionally at least one abrasion resistant layer ;
b) at least one insulation layer said insulation layer including one of an acrylic, an epoxy, a ceramic, glass or combinations thereof; and c) a pipe; wherein said insulation layer is proximate one of an inside circumference of said pipe, an outside circumference of said pipe, or combinations thereof, wherein said optional abrasion resistant layer is proximate said at least one insulation layer; and wherein said insulation has a compressive strength of >=200 psi, as determined by ASTM D-1621, and wherein said insulation has an R value >= 12 per inch, as determined by ASTM C 177-85.

3. The abrasion resistant, corrosion resistant insulated pipe of claim 2 wherein said pipe is part of a pipeline and wherein at least a portion of said pipeline is submerged in water.

4. The abrasion resistant, corrosion resistant, insulated pipe of claim 3, wherein said optional abrasion resistant layer, if present, is present at one of >= 10 or <=
40 mils, wherein said at least one insulation layer is present at a total thickness of one of >= 20 or <= 90 mils, wherein said insulation has a compressive strength of >= 400 psi, and wherein said insulation has an R
value of >= 14 per inch.

5. The abrasion resistant, corrosion resistant insulated pipe of Claim 4, wherein a primer is applied proximate said inside circumference of said pipe, said primer being spaced between said circumference of said pipe and said insulation, wherein said insulation has a compressive strength of >= 800 psi, and wherein said insulation has an R value of >= 25 per inch, wherein said insulation includes an epoxy, substantially free of phenolics, said insulation containing particles, said particles being one of asymmetrical, symmetrical, amorphous, non-spheroidal, spheroidal, or combinations thereof, and wherein said particles are one of ceramic, glass or combinations thereof.

6. Crude oil contained in a pipe comprising:
a) crude oil;

b) an optional abrasion resistant layer contiguous to said crude oil, said abrasion resistant layer including an epoxy, and;
c) an insulation contiguous to said optional abrasion resistant coating and proximate a pipe interior surface, where said insulation is positioned between said optional abrasion resistant coating and said pipe, wherein said insulation includes one of epoxy, substantially free of phenolics, glass particles, ceramic particles, or combinations thereof;
d) an optional primer spaced between said insulation and said pipe;
e) a pipe;
wherein said insulation has a compressive strength of >= 1500psi, as determined by ASTM D-1621,and an R value of one of >= 14 or <= 400 per inch, as determined by ASTM C 177-85.

7. A method of insulating a pipe, comprising:
a) insulating a pipe in the interior portion of said pipe; and b) optionally coating the insulation of a) with an abrasion resistant layer.

8. The method of claim 7 further comprising abrading said pipe prior to either a) or b); and priming said pipe subsequent to said abrading.

9. The method of insulating pipe of claim 8 wherein said abrasion resistant coating, if present, is present at one of >= 5 or <= 25 mils and said insulation is present at a total thickness of one of >= 10 or <= 90 mils, said insulation having an R value of one of >= 12 or <= 300 per inch, as determined by 85 and said insulation has a compressive strength of >= 2000 psi, as determined by ASTM D-1621.

10. The method of insulating pipe of claim 9 wherein said pipe is a portion of a pipeline, said pipeline including a least two pipe sections, and wherein said at least two said pipe sections are joined by welding, and prior to being joined, placing a cylindrical corrosion barrier inside the two proximate pipe ends to be joined, providing protection from heat generated from said welding, said insulation having an R value of one of >= 25 per inch.

11. The method of claim 10 wherein said insulation has a compressive strength of one of >= 800 or >= 3500 psi, as determined by ASTM D-1621, said insulation having an R value of one of >= 35 per inch.

12. A submerged pipeline comprising:
a) at least one pipe;
b) insulation, said insulation having an R value of one of >= 10 or <= 200 per inch as determined by ASTM C-177-85;
c) an optional abrasion resistant coating;
wherein said insulation is formed on the interior surface of said pipe, and wherein said optional abrasion resistant coating is formed on said insulation, wherein said insulation is present on the interior surface of said pipe at a total thickness of one of >= 5 or <= 100 mils, wherein said optional abrasion resistant coating, if present, is present on said insulation at one of >= 1or <= 40 mils.

13. The submerged pipeline of claim 12, wherein said pipeline is formed by welding pipe sections, wherein prior to joining two pipe sections, a cylindrical corrosion barrier is placed inside the two pipe ends being joined, and wherein said insulation has an R value of one of >= 14 or <= 80 per inch, as determined by ASTM C-177-85.

14. A pipeline insulated on its interior circumference comprising:
a) a pipe forming a portion of said pipeline;
b) >= two or <= ten layers of an insulation, said insulation placed on an interior surface of said pipe, said insulation having an R value of one of >= 14 or <= 200 per inch, as determined by ASTM C-177-85, wherein said insulation includes an epoxy, substantially free of phenolics, and one of ceramics, glass or combinations thereof, said insulation having a total thickness of one of >= 5 or <=100 mils thick; and c) optionally, at least one layer of an abrasion resistant coating, said abrasion resistant coating being an epoxy ceramic, said abrasion resistant coating, if present, being one of >= 1or <= 40 mils thick.

15. The pipeline of claim 14, wherein said insulation has an R value of one of >=
12 or <= 150 and being present at a total thickness of one of >=
10 or <= 90 mils thick, said optional abrasion resistant coating, if present, is present at one of >=
or <= 25 mils thick.