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Investigation & Application of Low Cost Pipe Insulation System 1992
INVESTIGATION AND APPLICATION OF LOW COST PIPE INSULATION SYSTEM Prepared for: Alaska Science and Technology Foundation 550 West 7th Avenue Anchorage, Alaska 99501 polarconsult alaska, inc. ENGINEERS ¢ SURVEYORS « ENERGY CONSULTANTS 1503 WEST 33RD AVE.e ANCHORAGE, ALASKA 99503 polarconsult alaska, inc.© Purpose of Investigation ...........ccsccccssessescssescssecesesecsecseeseesesseseeeeseeseeeeseseeaeeesees Application of System.... ‘ Past Approaches ........csccsccsssesssescecessessesesscsscescescecesseeseesceseeesseneeeeseaeeeseeseaeee Proposed Solution ..........cccscsccsssssessessessessesseeeseseeeseeseeseessesecsseeseeeseeaeeeseessesaeee i Typical District Heat Use : Illustrations 1 & 2. Typical District Heating System.............04. 9 Investigation Of Materials ............ccccscsesssesssssseseseeeesesceceseseseeseseeeeeacsesenensnenaees 10 Plastic Pipe 7 TYPOS .....ccccccsecseesecssceseesccsscsceseesseeaeeseeesesseeeececeaeeeeeeeeeeseeasenseas 10 Other Carrier Materials... cccsessssessssesesesesseseseeeeteneeeneneees 12 Connections . Freezing Considerations .0........ceccccccecssssesessesceseesescescseeeesesesees 14 Insulation .......cecesessescssessescesesesceseeseseeseesececseeseeaeseesecsesecseeseseescseseeeees Expanded Polystyrene . . Water COnditions ...........cccccscsseseeseseeeeeseeseeeesseseeeeseeseeeeaeseeeeeesees Operating Conditions ............c.csssesesesesesesseeeeeeeeeeeseeeeneneneneaeaneee ILLUSTRATION 3. Indoor Test System Schematic. : Fabrication & Assembly Techniques..........c.cceccssessesseesseessescesesseseesees Illustration 4 & 5. Insulation Details Illustration 6 & 7. Insulation Details Illustration 8. Hot Wire Cutting Tools Analysis of Results ............. Insulation Performance.......... : Fabrication & Assembly Techniques ............ccesecsscsseseeeeeeeeeees Illustration 9 through 12. Hot Wire Cutting & Misc. Insulation Details 0.0.0... ccsecscesecsseessseesscessecesseessesaeessenseense Indoor Test Conclusions .. Field Test System oe Purpose of Field Test System..... Assembly Techniques and Fabrication .... Investigation and Application of Low Cost Pipe Insulation System i polarconsult alaska, inc.© System Operation..........sccescssssesssessssesesecesssessseseseseesesesscsesesesseseseneees 36 Diesel Engine Coolant & Required Building Temperatures...... 36 Heat Exchange Devices .........cccscceeseseeseeeeee Kadeaseosen .. 36 Economic comparison............00+ Field Test Conclusions.. .39 Field Manual............ccccscsssssssssecssscescsscseesessesseeeseeees 40 Outline of Application .............:e:000 40 System Specifications ..........s.scseeee 42 Specification for pipe 0.0... eecssesecsessesseeeeeeeeeeeeeees 42 Specification for insulation.............scssesseeeseeeeeeeeeee 42 Appendix A uc. cescseseestesseeeteseeees wl PPPCTAK Bian eecl secs dsetscssatsasssanscastetasesttsvarenssssasvacassastetetelerccerebesnsedéoceMtsedesttenssesshes 2 PPPOTIK Cores nstesengtecsssbasnsoneacussssdasstebaatersararcacsssusussadcteleletensshsheodsdeandededelesepssetaneh 3 Investigation and Application of Low Cost Pipe Insulation System ii polarconsult alaska, inc.© —_ — OVERVIEW OF REPORT CONTENTS The "Summary" provides a synopsis of the results of the investigation, our conclusions, and recommended next steps to ensure vertical integration of this new process. The "Introduction" briefly explains the purpose and application of this investigation, the past approaches, our proposed solution, and typical district heat uses in Alaska. The “Investigation of Materials" section shows the results of our investigation into different materials considered for use in the indoor test. This involves the evaluation of tubing materials, insulation types, and working fluids for the system. The "Indoor Test System" section evaluates the results of the indoor test as it pertains to the materials that were tested. Fabrication of the insulation parts, the assembly process, durability of the system, and possible solutions to the problems encountered are covered. The "Field Test System" section discusses the key features that need to be included in the Field Test System. This is required to complete the evaluation for development of a field applications manual. The test protocol, criteria, and the recommended facility design is provided in this section. This will include further testing of the insulation's high temperature characteristics, the effects of operating the system underwater, and uses diesel engines as the heat source. The "Appendix" includes an outline of the Field Manual, the specifications of the materials and parts tested, and other supporting material. oo —— Investigation and Application of Low Cost Pipe Insulation System 1 polarconsult alaska, inc.© SUMMARY This report is about the development of a low-cost insulated pipe system for district heating, sewer, and water lines that can be used and manufactured in Alaska. The purpose of the report is to show the progress that has been made in this development, provide useful data for implementation, and recommend additional work needed to provide a fully operational low-cost insulated pipe system. Alaska Science and Technology Foundation (ASTF), and the engineers at Polarconsult Alaska (PCA), funded the work on this development, which officially commenced July 1990. ASTF's obligation was $53,800 and PCA's was $25,000. Difficulties in finding a source of special plastic tubing delayed installation of the test facility, until start-up in July 1991. This facility is continuing operation to test ideas to improve the system. Results of the work showed the system will be effective for temperatures below the test temperature of 194 degrees, and will result in a system which is lower in first cost than any other now in use. Indications are that installation costs will also be much lower. The tests showed that low-cost, locally made, polystyrene insulation (EPS) is marginal at 194 degrees, and that further testing should be done on this material. A copolymer of polystyrene, which is more costly, was tested and appears to readily withstand the test temperatures which would be used for district heating. Based on the test and analytic results, pending Field Tests, it is highly probable that the system can be used for most of the insulated underground water and sewer piping now installed in villages. The system will substantially reduce costs, and will be much easier to repair, tap, and extend than presently used systems. There are millions of dollars in potential savings that can be realized in Alaska if this system is applied to sewer and water pipe insulations alone. Alaska Energy Authority (AEA) agreed to field test this system. Collectively we have been searching for a site for the test. Site criteria includes, thermal and soil conditions, reasonable access, and a community which needs the service, so it will continue to operate, hence test the system over a considerable period of time. As of now such a site has not been found. Field Test results are very much needed to provide the information needed by the people who will design and build these systems, and to refine the economics of the system. The field test will further test the lowest cost insulation, more advanced cutting tools, and will test constructibility under varying field conditions. Data from the field test will also be used to refine the economics of the system, particularly construction. The intent is to use the results of the Field Test, to complete the Field Manual. This will be an instruction manual for users on how to implement the system. Although the grant was for district heating, the largest savings are likely to come from insulating sewer and water lines throughout Alaska. Investigation and Application of Low Cost Pipe Insulation System 2 polarconsult alaska, inc.© INTRODUCTION PURPOSE OF INVESTIGATION The purpose of this investigation is to evaluate a low cost method of building insulated pipe systems for the development of water, sewer, and district heating systems in Alaska. The insulated pipe system outlined in this report is designed to be less costly, and easier to install and maintain, than conventional systems now manufactured outside Alaska. The system has been designed so it may be constructed and maintained using local labor in the field. The goal of this study is ultimately to provide instructions on how to construct, or purchase, an inexpensive system that will be used to provide rural communities with utilities that they couldn't otherwise afford. This study was financed with a grant from Alaska Science and Technology Foundation (ASTF) and with donated time and effort by the Engineers at Polarconsult Alaska, Inc. APPLICATION OF SYSTEM This report focuses on a district heating application for the pipe insulation system. District Heating systems provide heat to users with hot fluids from a centralized source via a network of insulated pipes. A baseboard heating system in a house is similar. Generally the heat is transmitted by circulating a hot water or water antifreeze mixture. The most common form of this application, as now applied in Alaska, is to capture waste heat from diesel generators and to distribute it to public buildings. Heat sources can also be central or satellite boilers burning a variety of fuels such as coal, wood, or peat. Alternatively, a geothermal heat source may be used in such a system. In most circumstances, it is necessary to insulate the pipe network to protect it against freezing and heat loss. This is of particular importance in Alaska where permafrost is abundant and the frost depth may exceed the buried depth of the system, if the system is buried at all. Until now, the only solution has been to use expensive commercial insulated piping. While this is effective once installed, its initial cost, the technical expertise required to install it, and the cost of future repairs make it unfeasible for many rural Alaskan Communities to use. Investigation and Application of Low Cost Pipe Insulation System 3 polarconsult alaska, inc.© PAST APPROACHES The past approach for District Heating pipe has been to use commercially available insulated piping. This piping typically consists of a metallic carrier pipe insulated with an open cell polyurethane foam, surrounded by an impervious outer jacket. The impervious jacket is necessary to prevent degradation of the foam, and to prevent corrosion of the metal carrier pipe. Most district heating pipe installations constructed in this way are capable of operating at fluid temperatures up to 250°F. Insulated pipe for sewer and water systems is generally comprised of a polyethylene (PE) or a polyvinyl chloride (PVC) carrier pipe with the insulation, jacket and general construction identical to the district heating pipe. Temperatures of the water and sewer piping systems rarely exceed 50°F. Analysis of the fundamental requirements of the piping systems by Polarconsult determined that if district heating temperatures were sufficiently low, and/or higher temperature materials were used, insulation systems could be simplified. Plastic tubing, and unjacketed insulation which is commonly manufactured in Alaska could be used in this case. Most remote Alaskan communities rely on diesel power generation for electricity, consequently, they have a prime heat source available. Since the coolant temperatures for the diesel engines rarely exceeds 195°F, it is not necessary to use expensive urethane foam insulation which can withstand high temperatures. Further, current and past designs for water and sewer piping tend to use urethane insulation which is susceptible to water. This requires a water proof jacket regardless of the carrier pipe material to protect against insulation deterioration. Commercially available insulated pipe systems require special handling and shipping considerations which contribute to their higher costs. The conventional system described above requires the injection of foam between the impermeable outer jacket and carrier pipe. Such a system requires careful handling and installation. Pipe sections are limited to the economic shipping length of near 40 feet. This is significant because each section must be joined, requiring a pipe connection, a termination, an insert foam section, and a jacket connection. A typical district heating system may have hundreds of these joints that could leak water, and damage the system if not properly installed. Investigation and Application of Low Cost Pipe Insulation System 4 polarconsult alaska, inc.© PROPOSED SOLUTION The proposed solution is to use a high temperature plastic or coated metal tubing as a substitute for the metallic carrier pipe, and to use unjacketed closed cell foam insulation to reduce heat loss. Tubing is generally less expensive, easier to transport as it is available in long coils, and may be connected with simple bolted couplings. Air freight costs will be substantially reduced since tubing is far lighter than the standard steel carrier pipes used in the current systems. Fewer connections result in a more reliable pipeline, with less opportunity for leaks. Most of the connections are assembled with standard tools instead of welding. Closed cell foam, commonly used in the building industry, is manufactured and readily available at low prices in Anchorage. Initially this study investigated expanded polystyrene (EPS), however, our investigation showed that for higher temperatures, near or above 190°F, a copolymer of polystyrene may be necessary. Foam parts can be easily cut from blocks using a hot wire tool. In Anchorage, the insulation sections for the system can be cut inexpensively by the insulation producer with a computer controlled hot wire cutter, and delivered to the community. As discussed later, additional parts or specialty modifications can be fabricated in the field with a hot wire cutter if required. Investigation and Application of Low Cost Pipe Insulation System 5 polarconsult alaska, inc.© TYPICAL DISTRICT HEAT USE A typical district heating system is shown in Illustration 1 on page 9. Presently, this is the most likely type of system that may be adopted for use in Alaska. In the future, centralized boilers will also probably be used as a supplemental heat source as is done in Northern Europe. It is important to understand the typical operation of a district heating system as it strongly influences the conditions under which the piping/insulation system operates. The district heating system's operational temperatures largely control the selection of materials used for the system. Typical diesel generation district heating systems provide an engine coolant heat source which is limited to maximum temperatures near 195°F with an average temperature of approximately 190°F. All heat exchangers drop the temperature in the conversion, so the district heating system source temperatures typically range from 185-190°F. At the user end, with a typical hot water hydronic heating system, the water temperature going to the baseboard is normally 180°F, and 160°F returning. With a temperature loss of 5°F across the heat exchanger, the fluid in the district heating system going to the building heat exchanger would need to be at least 185°F to supply all the heat needed to prevent operation of the boiler. However, such a temperature range is necessary to provide all the capacity and is only needed during the coldest days when the maximum heat is required. For the usual case, there is more demand for district heat than can be supplied during peak heat demands. The temperature within the district heating system will have to drop to an equilibrium temperature between production and consumption. As a result, the boiler(s) will come on regardless. This means that with typical control systems, most of the heat will be used, however, there is a potential not to use all of the available heat under some conditions using conventional heating systems. This is because some conventional systems require high boiler temperatures regardless of the amount of heat needed. Modifications can be made to the boiler control systems which reduce the peak boiler temperature as outside temperatures moderate. In such a case, the district heating system will be able to transfer all of its heat to the user. Controls such as this also have the Investigation “7 ° plication of Low Cost Pipe Insulation System 6 polarconsult alaska, inc.© advantage of providing more efficient use of fuel, whether the district heating system is installed or operational. An alternative method of solving the problem is to add, or design, systems which do not require. as high of an operating temperature. In fact, "state of the art" district heating systems used in Europe do not have an individual heating plant in each building, as their sole reliance is on the district heating plant. It is economically feasible to do this where new housing and buildings are being designed and built in the villages. For this situation, lower temperature radiators can be installed into the community allowing direct use of the district heating fluid. A typical building connection of this type is shown in illustration 2 on page 9. Such a system lends itself readily to multiple pipe installations, and can also serve readily as a warm carrier for domestic water and sewage. Traditionally, the general school of thought has been that the construction costs of a particular district heating system using lower temperature fluid would be more expensive than a system using a higher temperature fluid. This is because as the temperature of the working fluid is decreased, additional fluid flow is required to deliver the same amount of heat, which requires larger pipe and, therefor, increases the initial cost. In Europe the practice is to use temperatures of up to 250°F. The working fluid is water in this case, and the heat source is central boilers, or steam power plant condensers. However, the Europeans have far more dense population centers that require large quantities of heat to be transported. In contrast, rural Alaskan communities are typically spread out and need smaller quantities of heat delivered. Further, in Alaska the soil temperatures are low, and in many cases ice-rich permafrost is present. As a result the transfer of heat into the soil can be a problem and must be avoided. This requires that high temperature systems be more heavily insulated. Unfortunately, conventional district heating piping is generally not available with thicker insulation, and when it can be obtained, it requires the use of high cost specialty fittings and accessories. Overlooking the numerous other drawbacks of conventional district heating systems as they pertain to Alaska, the cost associated with increasing the insulation usually overcome any savings gained by reducing the size of the carrier pipe. A numerical analysis of the optimization tradeoffs on this subject is outside of the scope of this investigation, but should be completed. A typical village should be chosen and optimization designs made to determine the most economical and best solutions. The comparison of alternatives should take care to include the operational characteristics of Investigation and Application of Luw Cost Pipe Insulation System 7 polarconsult alaska, inc.© the different systems. For example, a comparison of the operation of high temperature water systems, as compared to lower temperature water systems, requires the high temperature system have a consistent over pressure to prevent the water from flashing to steam. As a result, high temperature systems are more dangerous and require controls of much higher cost than those required for water below 212°F. Investigation and Application of Low Cost Pipe Insulation System 8 polarconsult alaska, inc.© ILLUSTRATIONS 1 & 2. TYPICAL DISTRICT HEATING SYSTEM TYPICAL BUILDING l95F 190F |\85F |8OF GENERATOR HEAT EXCHANGER TYPICAL DISTRICT HEATING SYSTEM ILLUSTRATION | TYPICAL BUILDING CONNECTION ILLUSTRATION 2 Investigation and Application of Low Cost Pipe Insulation System 9 polarconsult alaska, inc.© PLASTIC PIPE Plastic pipe has many desirable attributes that make it ideal for use in district heating systems in Alaska. Some attributes include a relatively low initial cost, durability, low maintenance, and lower shipping costs because of its inherent lightweight, and the ability to be transported in aircraft. TYPES For lower temperature, lower pressure applications up to 180°F High Density Polyethylene (HDPE) pipe may be used. In spite of these limitations, HDPE could be acceptable for many installations depending on their heating systems. The prototype system being investigated in this report, theoretically, would make the least costly district heating system. Such a system would be comprised of HDPE tubing and Expanded Polystyrene (EPS) foam. At a minimum, such a system would make an extremely low cost sewer and water pipe insulation system. For higher temperatures near 200°F and above, cross-linked polyethylene (PEX) is the preferred material. PEX plastic pipe is widely used for high temperature applications in Europe for District Heating systems, thaw pipes under sidewalks, inslab heating, and to distribute hot water for heating throughout buildings. Illustrating the vast use of this material outside of the U.S. is the following table showing feet of PEX tubing used in Germany, alone, and the total used in Northern continental Europe in 1990. TABLE 1. CROSS LINKED POLYETHYLENE PIPE USED [FT] 1987 1988 1989 1990 Germany _ 101,700,000 | 110,900,000 129,900,000 141,100,000 All of Europe - - : 208,700,000 The Europeans also manufacture a preassembled flexible pipe system which uses a single or double, plastic carrier pipe(s) surrounded by glass fiber with a corrugated plastic jacket covering. This system is manufactured by Wirsbo and ranges in cost from $17.60 per foot for single 3/4" tubing in 656' coils to $59.80/foot for 3" tubing in 164' coils. For double tubing systems, the costs are $24.50/foot for 3/4" and $57.85/foot for 1 1/2". List prices for tubing with and without oxygen barriers from Wirsbro, and a material price Investigation and Application of Low Cost Pipe Insulation System 10 polarconsult alaska, inc.© quote from 2H Kunststoff in Germany are shown in the following table. List prices from Wirsbro do not include freight to Anchorage. There would be an associated increase in costs for freight, and a reduction in costs for quantity. TABLE 2. SUPPLIED COST FOR PEX TUBING 1 Wirsbro tubing with oxygen barrier 2 Wirsbro tubing without oxygen barrier 3 2H Kunststoff, quote for a 10,000 meter quantity. Included in the cost is freight from Germany to Anchorage and a 3.8% tariff. This tubing is rated for 60 psi and does not have an oxygen barrier. 4 2H Kunststoff tubing, but with a pressure rating of 6 bar or 90 psi. To illustrate the staggering cost for the flexible insulation system, compare the system costs to the tubing prices alone. Subtracting the cost for 3/4" tubing from the cost for a single 3/4" flexible tube insulation system results in the cost for the insulation and jacket of $15.95/foot and $21.20/foot for double tubing. The insulation thickness for the flexible systems is less than 2" for 3/4" pipe and 2 1/2" for 3" pipe, making it unsuitable for many Alaskan applications. There are a number of other types of plastic pipe and tubing which are available to be used in a district heating systems besides PE. Fiberglass reinforced epoxy has certain advantageous properties, but is only available in rigid forms which, in conjunction with its high cost, make it an unattractive alternative. Another option investigated was polybutylene tubing. Though widely used in the United States for hot water piping in homes, this tubing was rejected because of its tendency to rupture when frozen, and since it is not available with an oxygen barrier. The sizes of pipe considered for use are mainly restricted by the availability of the tubing in a coil and the ability to handle it during installation. Tubing in a coil is generally available up to 3 inches in diameter and, to our knowledge, oxygen barrier tubing may be obtained up to 2 inches in diameter. The other d::\..ulty with plastic pipe can be handling. The pipe is coiled which is helpful when loading small aircraft, but it can be a Investigation and Application of Low Cost Pipe Insulation System 11 polarconsult alaska, inc.© problem to straighten out, especially when it is cold. The subject of handling will be dealt with in greater detail in the Field Manual. OTHER CARRIER MATERIALS Copper pipe systems have been used successfully mainly since they are more flexible and can better withstand corrosion than steel. Copper is, however, a more expensive material and as a result, is not widely used. In comparison to plastic, copper is not as resistant to freezing. In Europe copper is frequently used for the individual smaller connections. Insulated copper systems have been used to connect millions of Danish homes for under $1,000 each. Steel tubing in coils is readily available in Anchorage as it is used for down hole production of oil. In the past this tubing has been used in the installation of natural gas utilities. Its surface is protected from external corrosion by an extruded coat of polyethylene. Since then, it has been replaced by plastic tubing. Although this tubing might prove preferable to welded pipe sections, there is difficulty in getting it with the corrosion coating applied. Because of this, we have precluded its use. Investigation and Application of Low Cost Pipe Insulation System 12 polarconsult alaska, inc.© CONNECTIONS Connections for plastic pipe may require special considerations depending on the type of plastic being used. Pipe made from epoxy, chlorinated polyethylene, and polyvinyl chloride can be glued or solvent welded, HDPE cannot. For HDPE pipe the usual means of connection is fusion where the ends of the pipe are heated to 440°F and than forced together under about 60 psi depending on the product formulation. Other techniques, such as welding with hot air, are difficult, often resulting in joints weaker than the parent material. The pipe most likely to be used in district heating applications is cross-linked polyethylene (PEX) because of its higher temperature characteristics. These same characteristics make it difficult to fuse or weld PEX. As a result, metal fittings and connectors using a wedging action to hold the plastic pipe are used. One of the problems with this type of fitting is that under stress, most especially at higher temperatures, the plastic softens and loosens the connection, which can result in leaks. Another problem is these fittings do not generally develop the full strength of the pipe. Finally, the prices for these special fittings are high in comparison to standard fittings. As a result, when numerous fittings are needed for a short run of pipe, the cost of the installation is less favorable. There are many options to be considered when connecting metal pipe. Metal pipe may be welded, brazed, soldered, or connected with compression fittings in a similar manner to that used for plastic pipe as said above. The most reliable form of connection for steel pipe is welding. Although pinholes may occur and cracking can result from poor welding, it better approximates the strength of the parent material than other connection methods. As evidence to this, the Department of Transportation's regulations for oil pipeline welding allow up to a 90% joint efficiency for untested welds. Furthermore, welded joint failure on regulated liquid lines causes a very low percentage of system leaks. Incidentally, the great strength of steel provides the advantage of the system being able to operate at quite high internal pressures. For very long runs or for locations where there is considerable relief, this is an advantage over other materials. The problem with welding is it is only applicable to steel pipe which requires a high level of expertise and good working conditions to assure its quality. Brazing, although Investigation and Application of Low Cost Pipe Insulation System 13 polarconsult alaska, inc.© possible, is generally only used to connect small diameter steel tubing. A high percentage of failures have occurred with soldered joints on large diameter pipes. Although solder is technically strong, there have been numerous failures of soldered joints on district heating systems using copper pipe in northwest Alaska. Our examinations of many of these failed joints disclosed that only a portion of the joint was fully soldered. The joint failed in tension as the pipe shortened under extreme cooling. When analysis of a soldered joint is made, it is apparent that a superficial examination can not guarantee that the joint has been adequately penetrated by the solder assuring acceptable resistance to longitudinal loading. FREEZING CONSIDERATIONS Almost any pipe used for district heating purposes can burst if water is frozen in it. Many of the plastic pipes can withstand the expansion of localized freezing of water without failure. Some of the metal pipes can withstand up to 4 or 5 cycles without failure. Studies done by Wirsbo showed their plastic tubing would burst when the water in the pipe froze from each end towards the center of the pipe. The fluid in the center gradually built pressure until the capacity of the pipe was exceeded. The results of this study can be applied to even HDPE and other brands of PEX pipe as there is not enough elongation available in any material to withstand all possible conditions. However, HDPE and PEX pipe can withstand any number of freeze thaw cycles without detriment to the materials structure if it is not frozen in the manner described previously. As this is the usual case, it can be stated that, in general, polyethylene materials do not break when the working fluid freezes. Copper tubing of the soft drawn type can withstand up to several freeze thaw cycles. This statement is based on personal experience. According to tests done for Scepter by the University of West London, hard drawn and half hard drawn copper fails at the first cycle. These tests were compared to a composite aluminum-plastic pipe called "Kitec" manufactured by Scepter. This pipe withstood from 4 to 5 freeze thaw cycles. Of course, the diameter of the pipe plays a large part in the pipes durability to withstand such cycles. Investigation and Application of Low Cost Pipe Insulation System 14 polarconsult alaska, inc.© INSULATION EXPANDED POLYSTYRENE Expanded polystyrene (EPS) foam, familiarly know as "Bead Board", is currently being used for a wide variety of insulation applications in Alaska. This insulation is produced in Anchorage by Western Insulfoam who uses ARCO Chemical as their raw material supplier. Two pound per cubic foot foam insulation was donated by Western Insulfoam for use in the Indoor Test. The foam is produced by expanding premanufactured beads in a mold with steam. The resulting "Bun" is aged and later sectioned with a computer controlled hot wire cutting tool. Typical densities of this foam range from 1 to 3 pounds per cubic foot. EPS's thermal stability is a major concern when considering it for use in district heating systems. Unfortunately, information from the manufacturer is insufficient when trying to assess the insulation's performance near its thermal limits. For example, Western Insulfoam claims that the foam will retain its shape to 184°F and can be used to 167°F with occasional temperatures of 180°F. ARCO Chemical states that the foam is soft until the pentane blowing agent is lost and that when the insulation is new it becomes soft at 190°F, and after it ages at 210°F. Since this is unclear, the insulation was incorporated into the Indoor Test System. WATER CONDITIONS The insulation value of the of the foam varies depending on the density and application temperature. If the foam is in water it may absorb approximately one percent moisture between the beads. This adsorption results in about a 7% decrease in the insulations thermal performance. We have asked the manufactures about the effect of vapor as compared to submergence but have not received a definitive answer. According to Western Insulfoam, Cold Regions Research and Engineering Laboratory force saturated the foam with water to a total density equal to 10 times that of the foam alone. This apparently resulted in only a 20% reduction of the original R value. Immersion in water will affect this system in several different ways. As mentioned previously, the insulation quality will be reduced. Also, if the insulation is not well fitted, circulating water can extract heat at a rapid rate from the pipe. An additional problem may be the installation of the system in open water since it will tend to float. eee Investigation and Application of Low Cost Pipe Insulation System 15 polarconsult alaska, inc.© This may also be the case in ice rich ground without sufficient mineral soil above the insulated pipe to hold it down. THICKNESS A very important advantage of EPS is it can be easily cut to fit the parts requiring insulation. The insulation thickness can be varied to achieve the most economical system. For example, if there is permafrost under the pipe and it is desirable to reduce heat losses, the bottom thickness can be increased. In some circumstances it may be desirable to incorporate two pipes in the insulation in order to save material and reduce heat loss, EPS can be cut to accept such a system. The EPS board stock can be purchase in almost any thickness to meet the requirements of pipe insulation design. SOIL CONSIDERATIONS The application of this system will be affected by the soil conditions at the site. As discussed previously, thicker insulation may be used to keep the ground from thawing if the system is to be buried in permafrost. Also, if the ground is rocky, classified backfill will be needed to bed the pipe in order to protect the insulation. As an alternative, thicker insulation could be used to act as its own protection and retain the desired thermal properties. Because the insulation is somewhat fragile, it must be handled carefully and placed on a uniform surface. Other protection such as wood or geofabric may be use to shield the insulation from large rocks, etc. OTHER INSULATIONS Because of the problems with EPS insulation, ARCO was contacted and asked for recommendations for insulations with better high temperature properties. They recommend a copolymer of EPS which they call "Dytherm". This material which has a service temperature of 250°F, is used for interior automotive components, building panels, and for solar panels. Resin cost for this material is almost $2 per pound, versus $0.70 for EPS. Further, it is not available in as thick of board stock as EPS and there are not the same number of suppliers manufacturing it. This material is also cut with a hot wire, but at a slower rate. It is interesting to note that the price per cubic foot of copolymer quoted in Mississippi was $7.50 versus $3.00 per cubic foot for board stock, EPS, here in Anchorage. The base material price is $4.00 versus $1.40 respectively. »* lication of Low Cost Pipe Insulation System 16 Investigation polarconsult alaska, inc.© Expanding the copolymer in Anchorage is very feasible as it is also done with steam but with a higher pressure in the mold. See the quotation from Western Insulfoam for various shapes and board material in Appendix B. ——— EEE Investigation and A pplication of Low Cost Pipe Insulation System 17 polarconsult alaska, inc.© WORKING FLUID CONSIDERATIONS Traditionally, district heating systems have used water as the fluid to transfer the heat. An inhibitor is usually added to reduce corrosion in the carrier pipe, metal radiators, and heat exchangers if used. In Alaska, most of the district heating systems are charged with a 50% glycol water mixture which lowers the freezing point to -36 and -31°F for ethylene and propylene glycol respectively. The only exception to our knowledge, is Bethel where the system is run with plain water and operators are instructed to drain the system in the event of a loss of heat or pumping power. Ethylene glycol, which is used in automobiles and other engine driven equipment, is the most common anti-freeze found in Alaskan district heating systems. The Dow Chemical Company claims that a 30% solution of ethylene glycol and a 35% solution of propylene glycol is sufficient to protect a pipe from bursting at -600°F. Because of "environmental" concerns with ethylene glycol, propylene glycol has been substituted in some systems. Propylene glycol, a widely used food additive, is not as toxic as ethylene glycol, however both of the glycols are classified as a hazardous substances since they burn when pure. Neither glycols are flammable when used in standard water-glycol mixtures: One of the problems with propylene glycol is that its viscosity increases over 4 times that of ethylene glycol when it cools to near its slush point. This can result in pumping problems. As an alternative, potassium acetate is a new anti-freeze fluid being promoted by Chevron for use in ground loop heat exchange systems. This fluid is quite biodegradable, has low viscosity, and low toxicity. The boiling point is the same as for water (212°F) and does not present problems as the system will be restricted to a maximum temperature below this level. There are however, several disadvantages to using potassium acetate. It requires higher concentrations than glycol mixtures to prevent freezing. As a result, the heat transfer capability is not as good as for the glycols. For example, it takes 70% potassium acetate-water mixture to attain a -32°F freezing point, as compared to the approximately 50% glycol water mixture. It is also more expensive, about $6 per gallon in Seattle. Another problem is the product is so new that important design considerations, such as test data for oxygen absorption and degradation of the fluid in a oxygen rich environment is not yet known by Chevron. The fluid should be investigated in greater detail as more information becomes available. Investigation and A; tion of Low Cost Pipe Insulation System 18 polarconsult alaska, inc.© For steel pipe, the working fluid must be inhibited so internal corrosion will not take place. The system may use unmixed water as a working fluid if freezing problems can be avoided. In Europe the water is charged with various inhibitors to prevent corrosion of the metal. If plastic pipe is installed without an oxygen barrier or the system is configured so it can adsorb oxygen, steel parts connected into the system will corrode. To prevent this the system's fluid must be tested on a regular basis along with the addition of strong inhibitors. Dow claims that their glycol system protects metal even under such oxygen saturated fluid conditions. Ee Investigation and Application of Low Cost Pipe Insulation System 19 polarconsult alaska, inc.© INVESTIGATION OF OTHER SYSTEMS I.C. MOLLER DISTRICT HEATING PIPE SYSTEMS: Currently, i.c. Moller pipe is the most commonly used district heating pipe in Alaska. This piping system was first used in Alaska by Polarconsult in Tanana. The district heating pipe is manufactured by the i.c. Moller Company which is headquartered in Denmark. This pipe is of very high quality and its application has been thoroughly thought out. Clear instructions for its use have been prepared by the manufacturer, and, as shown below, it is expensive. To the best of our knowledge there have been no failures of this pipe in Alaska since our initial installation in 1986. Steel is one of the most common materials used for the carrier pipe in district heating systems and is exclusively used by i.c. Moller. Generally it is manufactured in 20 to 40 foot lengths, with urethane insulation, and an outer jacket of corrugated metal or plastic pipe. Special fittings are used to make the connections, and taps. Welding is usually mandatory for all connections which include T's, branches, reducers, increasers, bends and valve connections. In addition to these fittings are the items needed to reestablish the insulation and the water proof outer protective jacket. These items range from premanufactured "C" sections of foam with external jackets of polyethylene material which shrink when heated, to sophisticated polyethylene coated metal jackets, with zinc anodes, which are filled with urethane foam from a specially sized application packs. The the large thermal expansion characteristics of steel pipe requires, in many circumstances, it be welded. The steel pipe develops considerable stress when it expands and contracts since the temperature differences can exceed 200°F. Special designs are needed to support the thrust and tension of the steel pipe and to prevent exceeding the stress levels. Steel pipe must be installed with special bends, anchors, and pretensioning fittings to reduce the compressive forces when the pipe heats up. As a result the welded fittings are very important to the integrity of the system. Illustrations and information from the i.c. Moller catalog have been included in appendix A to provide a better understanding of their system. Presented in the table below are estimated costs for i.c. Moller pipes and its fittings in Anchorage. The last pipe supplied to Alaska was shipped several years ago to Alaska Energy Authority, AEA. Investigation and Application of Low Cost Pipe Insulation System 20 polarconsult alaska, inc.© TABLE 4. COSTS FOR I.C. MOLLER PIPE & FITTINGS IN ANCHORAGE Dia, inch OD, inch | $/90° Bend $"'T" 3/4" 43" $40 $79 1" 4.3" $40 $79 1 1/4" 4.9" $50 $88 11/2" 4.9" $50 $88 2" 5.5" $60 $91 2 1/2" 6.2" $67 $106 3" 7.9" $74 $120 Note:It should be understood that two pipes are involved, and it takes two fittings for each connection. Further, all connections are made by welding the pipe. This pipe system is available with alarm wires, which can be used to indicate when water leakage gets into the insulation. To our knowledge, there are no alarm systems used on this type of pipe in the State. Consequently, corrosion may be taking place without anyones knowledge. EEE Investigation and Application of Low Cost Pipe Insulation System 21 polarconsult alaska, inc.© MATERIAL CONCLUSIONS All piping materials have their advantages and disadvantages. With the information above it is becoming evident that the plastic pipe has properties which make it favorable for district heating at modest temperatures and may be suitable for us with EPS insulation. Material costs for the proposed insulated piping system constructed with PEX tubing from 2H in Germany and EPS insulation compare to current system designs as follows: TABLE 5. COMPARISON PRICES FOR INSULATED PIPING SYSTEMS Manufacturer PEX w/ EPS single pipe double pipe Wirsbro single pipe double pipe i.c. Moller single pipe double pipe Note: These It should be understood that fittings are not included in these prices. The Indoor Test System described in the next section was constructed with PEX pipe and EPS insulation such as is shown in the cost table above. Investigation and Application of !.uw Cost Pipe Insulation System 22 polarconsult alaska, inc.© INDOOR TEST SYSTEM PURPOSE OF THE INDOOR TEST The purpose of the indoor test was to subject the piping system to many of the conditions that it would experience in the field. These included testing the feasibility of fabricating the insulation parts, assembling the pipe-insulation test loops, and assessing the durability of the pipe-insulation system. DESIGN OF SYSTEM The system was designed to model the conditions experienced in full sized district heating systems. The design of the indoor test system consisted of a small electric hot water heater, pressure tank, pump, and the pipe-insulation test loops. See illustration 3 on page 25. PIPE Of the different types of piping evaluated under Section III-A of this report, 1-1/2 inch Wirsbo-pePEX, and 1 inch Scepter Kitec pipe were selected for use in the insulation system. These products were chosen because they conformed to the criteria outlined in the Material Investigation Section. Wirsbro-pePEX has the following properties/benefits: - No corrosion, since the tubeing is made of plastic. The material is also highly wear-resistant. - Wirsbo-pePEX tubing has a "thermal memory" which ensures that after the material has been heated to approximately 266°F, it will revert to its original shape. This property can be used to correct a kink in the tube. - The tubing is delivered in standard lengths up to 790 feet, which minimizes the number of joints and reduces the material wastage. - The low internal friction of the material results in low pressure drops. - The tubing is designed for a pressure of 145 psi at 194°F, but can also withstand temperature surges up to 230°F. Investigation and Application of Low Cost Pipe Insulation System 23 polarconsult alaska, inc.© Wirsbo-pePEX tubing is a further development of Wirsbo-PEX tube of cross-linked polyethylene. The new Wirsbo pePEX tubing incorporates an oxygen diffusion barrier. See the appendix for more information. The Kitec product consists of an aluminum tube laminated between two layers of cross- linked polyethylene. The aluminum tube is formed from ultrasonically welded aluminum strips. These strips are then coated with polyethylene using a melt adhesive. The aluminum tube has the advantage of being flexible and holding its shape which proved to be an installation advantage over all plastic tubing. Other advantages are the tubing provides a complete oxygen barrier and it is easy to locate with a metal detector. The scope of this report is limited to the pipe's effect on the insulation and the ease of installation. INSULATION Though many insulations were considered for the Indoor Test, Western Insulfoam's expanded polystyrene was initially selected due to its low cost and local manufacture. After it was determined that the Western Insulfoam product was deteriorating, further testing was performed on it and Arco's "Dytherm" copolymer foam insulation. OPERATING CONDITIONS As discussed previously, typical district heating systems will see a maximum temperature of approximately 190°F. The fluid temperature in the test system was maintained at a slightly higher temperature to subject the insulation to more rigorous, unusual conditions. The test system was cycled from hot to cold to simulate the conditions under which the heat source is removed and returned. The pressure of the system was maintained at 50 psi. Pressures in typical district heating systems may be different but would have a negligible effect on the pipe-insulation process being evaluated. The surrounding media consisted of pea gravel. This would be representative of the material used as backfill for many district heating, sewer, or water systems. Investigation and Application of Low Cost Pipe Insulation System 24 ST majsk§ uoynnsuy adig 180 MoT fo uoyvaijdd y puv uoyvsysaauy OVERFLOW OR PRESSURE RELEASE LINE ——__—_— GRUNDFOS PUMP TYPE UPS |5-42F PIPES LEAVE SANDBOX AT APPROX. 7° BELOW BOX SURFACE (2° ABOVE CONCRETE) SANDBOX 8’ WIDE X 12-4" LONG X 19° TALL r LD. SCEPTER KITEC METAL PIPE |V/2°LD. WIRSBRO PE-PEX PLASTIC PIPE TEMPERATURE CONTROL BOX (DAYTON) 1/2 GALLON WATER HEATER EXPANSION TANK PRESSURE GAUGE PIPES ENTER SAND BOX AT APPROX. |2" BELOW BOX SURFACE (7 ABOVE CONCRETE) INDOOR _TEST SYSTEM SCHEMATIC ILLUSTRATION 3 OLLVWHHOS WALSAS LSAL YOOGNI “€ NOLLVULSNTI @ dul ‘eyseye ]NsuOdIejoOd polarconsult alaska, inc.© FABRICATION & ASSEMBLY TECHNIQUES Fabrication and assembly was conducted at the indoor site in the same way that it would be conducted in the field. The insulation supplied by Western Insulfoam was obtained in 3x6x48 inch blocks and 96x48x3 inch sheets. All insulation tested from Western Insulfoam had a density of 2 pounds per cubic foot. These blocks were notched to accept the pipe using a hot wire cutter and plywood jigs. The system as we designed it required the use of two hot wire cutters, one cutter was used to form straight sections and one for sharp curves. The cutter shown in Figure 1, in Appendix A, & Illustration 8 on page 29 was used to make straight sections and simply consisted of a PVC tubing frame with electrical attachments, connecting Nichrome wire to a variable transformer. The curved sections were formed using a bent Nichrome wire on a rotating jig. See Figure 2 in Appendix A, & Illustration 8 on page 29. By adjusting the transformer, the operator was able to regulate the temperature of the wire for good cutting quality and speed. This apparatus is a simple portable version of large industrial heat cutting tools used to cut plastics and foams. ' The straight sections were cut using a plywood jig to guide the hot wire through the foam. This resulted in the quick and efficient production of the foam insulating pieces. The bends were produced by setting the hot wire jig on the foam block and rotating the arm. By using this technique a curved slot was cut in the foam at a radius equal to the length of the arm. The piece was finished by using the straight hot wire cutter to trim the edges of the foam to size. This part of the process proved to be difficult, and resulted in an uneven cut. Fortunately, the unevenness in the cut was just cosmetic and since we had only four curves to produce and extra foam, mistakes could be made. We suggest that for the Field Test System the foam is cut to width with additional hot wires while cutting the slot for the pipe. The parts were attached together using fiberglass reinforced strapping tape. See Figure 4 in Appendix A, & Illustrations 4 through 7 on pages 27 & 28. This connection system proved to be perfectly adequate for the Indoor Test System and would work well for the Field Test. The strapping tape primarily held the parts in place during the assembly and backfilling of the system. Once the system was buried, the parts were held together by the surrounding soil pressure. Investigation and Application of Low Cost Pipe Insulation System 26 polarconsult alaska, inc.© ILLUSTRATION 4 & 5. INSULATION DETAILS POLYSTYRENE INSUALTION W/LAPPED JOINTS STRAPPING TAPE TYPICAL VIEW PIPE INSULATION ILLUSTRATION 4 TYPICAL "T” OR "TAP” INSULATION ILLUSTRATION 5 Investigation and App!’ _...1 of Low Cost Pipe Insulation System 27 polarconsult alaska, inc.© ILLUSTRATION 6 & 7. INSULATION DETAILS POLYSTYRENE INSUALTION PLASTIC STRAPPING €/ OR GLLE CARRIER PIPE, HDPE OR PEX TYPICAL PIPE INSULATION JOINT DETAIL ILLUSTRATION 6 90° INSTALLATION ILLUSTRATION 7 Investigation and Application of Low Cost Pipe Insulation System 28 polarconsult alaska, inc.© ILLUSTRATION 8. HOT WIRE CUTTING TOOLS POWERSTAT VARIABLE —_— TRANSFORMER TYPE =e 3PNIC O TO I20 VOLT { OUTPUT 1/2" T CUT AT ANGLE 147 | | | | + ——NICHROME WIRE VARIABLE VOLTAGE |! TRANSFORMER | | es 0 INSULATED WIRE | 0 0 CONNECTED TO J\, | EYE BOLT / \ SPRING \ | , Pe ee \ | | | >—— | 1 vz" Pve | - | > = - | | L L-~ \ / fl N - v - — \ / \ SS a \ J 1V2" PVC ‘T N74 90 ELBOW wea HOT WIRE CUTTING TOOLS ILLUSTRATION 8 INSULATED WIRE HOLES DRILLED IN 4") PLYWOOD FOR |S" ; 7 TO 25° RADIUS ate = 13/8" V4" PLYWOOD 1 V2 WIDE X 28° LNONG NICHROME WIRE Ii/l6é° RADIUS Investigation and Application of Low Cost Pipe Insulation System 29 polarconsult alaska, inc.© ANALYSIS OF RESULTS INSULATION PERFORMANCE Our testing showed that the insulation melts when subjected to higher loading at the elevated temperatures. The bends provided a higher load on the insulation than the straight sections and as a result, the insulation had melted farthest along the curves. See Figures 7&8 in Appendix A. The straight sections had also melted downward a small amount. The melting in these sections could be attributed to gravity. To develop a more through understanding of the effect that temperature and load has upon the insulation, a series of insulation test blocks were installed on 3/4 inch copper tubing, and weighted with varying loads. See Fizures 5&6 in Appendix A. The rate at which the insulation melted, and the tube moved through the insulation was measured over time. See Figure 12&13 in Appendix A. The attached graph shows the distance that the insulation melted during the test. Load vs. Creep 14 — 12 g 5 10 2/27/91 wo 8 sD — — — 2/22/92 Beare 3/1/92 Sf 2 0 0 0.5 1 1.5 2 2.5 3 3.5 Weight Suspended From Insulation (Lbs) This melting may be a result of the "ageing" characteristic of EPS foam in which case the foam may become stronger with time. However, it may also be the result of excessive loading. What is not known is whether there will be continued melting or whether as appears may be the case, the melting subsides with time. This uncertainty requires that the EPS be further tested in the Field Test. Investigation and Application of Low Cost Pipe Insulation System 30 polarconsult alaska, inc.© Besides additional tests on the insulation, there are several mechanical solutions which should be tried. They involve the application of a simple support system to distribute the load over the insulation. Such a support could easily be fabricated in the field or elsewhere as shown by its simplicity in illustration 12 on page 30. Another possibility which was briefly explored is the use of core insulation with superior high temperature properties to reduce the temperature of the EPS. It should be understood that with increased insulation thickness there is a reduced temperature gradient through the insulation. This increases the temperature of the pipe/insulation interface. Another solution to the insulation problem would be to provide a central core of copolymer and to use what should be lower cost board stock EPS for the outer portion of the system. With the simple binding process using filament tape, it is no problem to add insulation. a Investigation and Application of Low Cost Pipe Insulation System 31 polarconsult alaska, inc.© ILLUSTRATION 9 THROUGH 12. HOT WIRE CUTTING & MISC. INSULATION DETAILS ADJUSTABLE 3/16°X2" ALUMINUM OR FIBERGLASS PIVOT 7 BI2 INSULATED COPPER WIRE TRANSFORMER _~ HOT WIRE INSULATION CUTTER LLUSTRATION 9 STANDARD STAINLESS STEEL PPE CLAMPS NICHROME WIRE INSLLATED BUSHING t— INSULATED WASHER INSULATION 3—-——— SPRING FORM WRE 3/16" THREADED PLASTIC WIRE CONNECTOR BEND TIE DETAIL ILLUSTRATION IO LLUSTRATION 1 HEAT PROTECTOR INSULATION ILLUSTRATION I2 Investigation and Application of Low Cost Pipe Insulation System 32 polarconsult alaska, inc.© INDOOR TEST CONCLUSIONS The development of the indoor test system was an outstanding success because it illuminated the advantages and disadvantages of the system. Advantages: - The indoor system showed that the concept of the insulation system assembly and field repairs are more easily effected than first anticipated. - Procurement of tools, such as the hot wire cutters, is simple and inexpensive. - The process of cutting the insulation which may be required for repairs, is simple and requires little instruction. Disadvantages: - The insulfoam material was found to deteriorate under the temperature and loads in the system. - Difficulty was encountered assembling the curved insulation pieces onto the bent plastic pipe. For reduced temperature installations, or where the temperature is low in the return pipes, EPS insulation will likely be the material of choice. However, controls will have to be provided to ensure that full temperatures are not seen on the return side if the thermal limit of the EPS might be exceeded. The indoor test has provided valuable information that will guide the development of the Field Test System. The advantages listed above have been further refined so that assembly and manufacture of parts will be simpler for the Field Test System. The disadvantages have been addressed and redesigned to avoid these problems in the Field Test System. Investigation and Application of Low Cost Pipe Insulation System 33 polarconsult alaska, inc.© FIELD TEST SYSTEM PURPOSE OF FIELD TEST SYSTEM The purpose of the Field Test is to evaluate the insulation system under actual field conditions, and to allow the implementation of solutions proposed in the Indoor Test. The Field Test is necessary to provide conclusive facts about the long term and short term performance of ihe insulated pipe system. As discussed prior to this, it is evident that further testing of the EPS insulation is warranted. In addition, system performance when submerged in water still needs to be measured. The systems constructibility and performance under the climate and conditions of a suitable rural Alaskan community must also be determined. Perhaps the most important part of the Field Test is to evaluate the community's response to the system, and develop strategies to educate them about the systems advantages. ASSEMBLY TECHNIQUES AND FABRICATION The Field Test will require the production of somewhat improved fabrication and assembly tools. The Indoor Test led to ideas for improving the design of the hot wire cutting tools. See Illustration 9&10 on page 32. A more advanced jig is also proposed which can be made using Bakelite in order to avoid the problems of the wire burning into the plywood jig. Manufacture of the parts should also be tested using a bandsaw and a router to cut the parts as this equipment is available in many villages. The Field Test will make it possible to finalize the design of these tools so they will operate efficiently and allow the quick manufacture of quality insulation parts for repair and construction. Manufacture and testing of metal and fiberglass tubing supports should be completed to determine if these are effective in reducing insulation damage when using low temperature EPS. In addition, a special connection for buildings should be designed, fabricated, and tested to withstand frost heave and freezing. Investigation and Application of Low Cost Pipe Insulation System 34 polarconsult alaska, inc.© SYSTEM OPERATION DIESEL ENGINE COOLANT & REQUIRED BUILDING TEMPERATURES Diesel engine coolant temperatures will need to be monitored to determine the temperature history the system experiences. The Field Test System should be limited to 195°F. Additional investigation should be conducted as to the temperature of typical village boilers in order to determine their actual operational characteristics. Although design parameters for boilers are usually 180°F on the hot side and 160°F on the cold side, the systems in the buildings may have been modified so they should be checked. HEAT EXCHANGE DEVICES There are many different types of heat exchangers in use. The "plate" design has probably seen the most use in Alaska in district heating systems. Other exchangers include shell and tube, and coil designs. The shell and tube type generally have less surface area and greater temperature differentials across them. Coil types can be used to heat hot water for potable consumption. Heat exchangers tested in the Field Test should be representative of the types used in the community. After use, they should be examined for evidence of corrosion. In addition to liquid to liquid heat exchangers, different types of baseboard heaters should be tested for community use. Dow Chemical claims that their inhibited glycol anti-freeze will protect steel baseboards. This should be tested, however, before a full scale installation is constructed. eee Investigation and Application of Low Cost Pipe Insulation System 35 polarconsult alaska, inc.© ECONOMIC COMPARISON Life of the system will be estimated from the results of the Field Test System, and from the manufacturer's testing information of the various components. Maintenance requirements will be determined from anecdotal evidence of other district heating systems. Equipment and piping sizing charts, and specifications will be provided with input from the Field Test. There are certain interrelated empirical rules of thumb that can help determine the size of pipe to use. The friction losses for tubing are the fifth power of the diameter at constant flow, the heat loss of the tubing is related to the first power of the diameter, and the quantity of material used for the carrier pipe, hence cost, is a function of the diameter squared. Further complicating the matter, the cost of fittings for tubing increase dramatically with added size. In fact one of the problems with the use of plastic pipe is the high cost of the fittings which are specially made for some types of pipe. The table below shows the capacity of plastic piping systems to transfer heat from a diesel electric generating plant. Based on the pipe diameter, the capacity is given in gallons per minute of fluid, Btu per hour supplied and the equivalent kW being generated over the time period. Several assumptions accompany this table. Head loss is estimated at 2 foot per 100 feet of pipe. 1 foot per 100 foot is typically used in Europe. The heat flow estimate is based on a 20°F drop in temperature, and that heat extracted from the cooling water is equivalent to the kW produced. Both of these assumptions are fairly typical for actual cases. TABLE 3. BTU CAPABILITY OF PLASTIC TUBING @ 2' OF HEAD LOSS PER 100' Several conclusions may be drawn from this chart. First, 1 1/2" pipe is sufficient to carry all the heat produced by the power plant engines in many villages. Further, given a5 psi heat exchanger loss, and 60 psi pipe, the system could extend 3,125 feet from the source and still remain within the pressure parameters assuming the system was relatively level. Investigation and Application of Low Cost Pipe Insulation System 36 polarconsult alaska, inc.© At 70% efficiency, it would take a four horsepower pump to fully utilize the entire pressure and flow capacity of 1 1/2" tubing. In short, for many rural Alaskan communities the small diameter, low pressure pipe would be more than sufficient to supply all of the heat available. The design and specifications for the equipment and tools to do the work will be provided based on the experience with the Indoor Test System. It may be economical to do the majority of the cutting at the foam manufacturers plant. Investigation and Application of Low Cost Pipe Insulation System 37 polarconsult alaska, inc.© FIELD TEST CONCLUSIONS It is necessary to conduct a Field Test to demonstrate that the system is suitable for use in low temperature district heating since there are still many unknown factors yet to be evaluated. Once the Field Test System has been completed, the answers will be available to provide assurance that the system is suitable for full scale implementation. Investigation and Application of Low Cost Pipe Insulation System 38 polarconsult alaska, inc.© FIELD MANUAL The purpose of the Field manual is to outline the steps required for choosing the appropriate application for the insulated pipe, size of the system and consideration of other important design features. The Field Manual will be developed with the information gathered from the Field Test System. The Field Manual will incorporate a series of standard designs which may be applied under different temperature and operational conditions. The standards will offer a stepwise procedure to arrive at economical answers. OUTLINE OF APPLICATION CHART OF STEPS This is a chart which graphically outlines the steps necessary to arrive at the design of a simple district heating piping system. EXPLANATION OF STEPS This section defines and explains each of the graphed steps. SYSTEM SCHEMATIC A schematic is shown for typical systems to provide comparisons for the application of the manual. CALCULATION OF SYSTEM SIZE Guide lines for the selection of pipe sizes will be included with a chart for calculation. ASSUMPTIONS All assumptions will be listed. SELECTION OF WORKING FLUID Pros and cons, and a cost analysis of the different types of fluids will be presented. The manual may only offer one fluid. HEATING REQUIREMENTS Recommendations on how to obtain information defining the amount of heat that will be required will be included. HEAT AVAILABILITY The amount of heat available is particularly hard to arrive at from a cyclical heat source such as a Investigation and Application of Low Cost Pipe Insulation System 39 polarconsult alaska, inc.© diesel electric power plant. Some rules of thumb will be provided, and information provided on how to record the necessary data to perform a more sophisticated analysis if it is warranted. AEA has a program, for the first time, to measure output of plants in selected communities. This information will become invaluable for the field manual when it becomes available. ROUTE SELECTION Instruction will be provided on how to determine what effects length will have on the system. Parameters include pressure drop, pumping power, and heat loss from the system. SERVICE CONNECTIONS Service connections will be shown schematically, along with a bill of materials and the vendors who can supply them. PIPE SIZING TABLE A table will be provided to aid in sizing the pipe. PUMP SELECTION Typical pump curves will be shown, and a selection example gone through. Typical costs will be presented as well. HEAT EXCHANGER SELECTION Heat exchanger data will be presented to aid in selection of these units. Along with selected manufactures data will be vendor names and some typical costs. DETERMINATION OF FLUID TEMP. Basic rules will be provided for determining the temperature of the working fluid and to aid in the selection of the type of fluid to use. INSULULATION THICKNESS A comparison chart which will provide insulation thicknesses versus ambient conditions will result in a guide to select insulation type and thicknesses. Parameters for the comparison will be fluid temperature, size, and conditions. Investigation and Application of Low Cost Pipe Insulation System 40 polarconsult alaska, inc.© SYSTEM SPECIFICATIONS SPECIFICATION FOR PIPE -Typical short pipe specifications will be provided. -Names of vendors will be provided -Installation requirements and instructions for the pipe will be provided. -Handling information and recommendations will be provided as a result of the field testing. -Construction information will be given. -Fitting types, recommendations, use, and a list of vendors will be provided. -Safety issues will be discussed as to anti freeze, uncoiling tubing, hot wire cutting, etc. -Other special details. SPECIFICATION FOR INSULATION -Short specifications will be provided for the different types of insulation as well as a short specification on geometry if cut sections are to be purchased. A list of vendors and typical pricing will be provided as well. -Installation requirements will be discussed. The installation characteristics will influence the insulation thickness. -Thickness information and selection criteria will be provided. -Procurement decisions will be discussed to aid in selection of vendors and systems. -Cutting techniques and equipment will be given. -Fabrication specification and instruction will be provided. -Typical connection details will be provided. -Results from the field test will be incorporated. - How to deal with water will be included in the manual. -Testing of the completed system will be discussed and recommendations made. -Backfill material and execution criteria will be provided. Investigation and Application of Low Cost Pipe Insulation System 41 APPENDIX A Figure 1 & 2 Figure 3 & 4 Figure 5 & 6 Figure 7 & 8 Figure 9 Figure 10 & 11 Figure 12 & 13 polarconsult alaska, inc, © Figure 1. Hot wire cutters were quickly and easily made for the pur- pose of cutting the insulation. The one shown in this photograph is for cutting the straight sections. Figure 2. The other cutters hown here was used to cut slots in the pipe for the curvedsec- tions. The right hand end of the tool was anchored to the insu- lation sheet using a nail. The hot loop on the left end was then dragged through the insulation there by cut- ting a notch in the in- sulation. eee Investigation and Application of Low Cost Pipe Insulation System polarconsult alaska, inc. © Figure 3. The insu- lation was cut and hand fitted on to the pipe loops. This en- tire process was simple to perform and proceededrather quickly, Figure 4. The pipe loops are shown here completly insulated. Note the use of strap- ping tape to hold the insulation in place during assembly and burial. Investigation and Application of Low Cost Pipe Insulation System polarconsult alaska, inc. © Figure 5. Shownin this photograph, from left to right, is the water pump, the water heater with thermostatic con- trols, and the pres- sure tank, Figure 6. The insu- lation blocks hang- ing off of the back pipe are being tested for their resistance to heat under differ- ent loads. The first eight blocks are made locally by Western Insulfoam and the last seven are ahigher temperature product called Dytherm. Investigation and Application of Low Cost Pipe Insulation System polarconsult alaska, inc. © Figure 7. After sev- eral months in op- eration the pipe loops were excavated and examined. Areas of highloading were found to have dete- riorated the Western insulfoam product. These sections fit snugly against the pipe immediately af- ter installation. Figure 8. The dete- rioration of the in- sulation was particualrily evident in the corners. This was most likly due to the load that the pipe exherted against the insula- tion as a result of internal stresses from installation and thermal expan- sion. Investigation and Application of Low Cost Pipe Insulation System polarconsult alaska, inc. © Figure 9. These cross sections of insulation were taken from the Wirsbro pipe loop at the end of the test period and graphically show the difference between the curved and straight parts of the test loops. To the leftis the straight portion, next the beginning of the curve, and to the right, the middle of the curve. oo 8 9 6 8 © @ Ene Investigation and Application of Low Cost Pipe Insulation System polarconsult alaska, inc. © Figure 10. Foam pipe insulation was investigated for use in highly loaded ar- eas in conjunction with the low tem- perature foam. This foam rubber mate- rial preformed poorly as evidenced by the cracks. Figure 11. The in- sulation shown here is an inexpensive commercially avalible poly- ethelene foam pipe insulation. Though it is rated to 210 de- grees Faren-heit it has melted at the pipe/insulation in- terface. Investigation and Application of Low Cost Pipe Insulation System polarconsult alaska, inc. © Figure 12. By in- crementally loading the insulation blocks, better under- standing of the de- terioration process was possible. This understanding has led to our proposed solution that will be evaluatedduring the Field Test. Figure 13. Afterone week of being loaded at 3/4 psi the West- ern Insulfoam specimin has moved 1/2 inch. The Dytherm product (not shown) has not moved at all. Investigation and Application of Low Cost Pipe Insulation System APPENDIX B SUPPLIER DATA ITEM Western Insulfoam quotation, cut and boards Stadler Bulletin showing feet of tubing used for slab heating Wirsbo Coupling similar to that used for test Wirsbo Insulation System, flexible, similar function to that proposed 2H Kunststoff GmbH, prices on PEX tubing from Germany Scepter, "Kitec" tubing, used for test ic. Moller insulated pipe which is normally used in Alaska WESTERN INSULFOAM CORPORATION 620 OCFAN DOCK HOAD « ANCHORAGE, ALASKA au507 QUOTATION To: POLAR CONSULT ALASKA, INC. 1503 W. 33rd AVE, SUITE 310 ANCHORAGE, AK 99503 6 TEE PHONE 497 89 440 Project: PIPE INSULATION - AYN: EARL AUSMAN Quantity Material ITEM I 2.0 Llb/ei ar | Prices firm for. 120 _days: subic x Page of WHITE. Custos VELSOW Choctee Fie Car oam P.o2 999 Quote No 09-292 Daly 2-21-92 6.0.8 Anchorage Plant 4.59 2d funn: Net 30 Amount $.87/1£ $1.50/1f£ $2.66/1f $1.10/1£ foqucte Prereatter WESTERN INS Wp EOA asa NM Cees Approved 19 By QUOTATION To: Quantity | Materia! ITEM VI | HE a“ | JR” “ SHIPLAPPED ENDS UPCHARGE +) <x ar 2" x 2' x g! 2.0 3" x 2' x 8! 4" x 2" x Bt CUTTING WIRE Hoskins MFG Co. Hamburg, MI 48139 | 22 yuage Chramel A WHITE: Customer Copy YELLOW Gute Fie Coy Fis lifes | No. C43 RH T.R9G35 Mays. nutyeet beens barns, Amount $2.00/1£ $4.10/1F eo oe ee $ .16/LE $8 .00/pe $12.00/pe $16.00/pe » Meg’, Kooi Le. we Clo ye LSS AM , ¥ Approved 19 lav <s STADLER Bulletin Subject: Annual Footage Totals For Europe No. 18 Annual Footage Totals For Europe Plastic Underfloor Tubing Reprinted from the August ’90 issue of the German Plastic Industry Weekly Trade Bulletin Total footage of plastic tubing sold in West Germany Material 1983 1984 1985 1986 1987 1988 1989 1990 Polybutylene 9.8 15.4 13.8 8.2 6.6 4.9 4.6 3.6 Polypropylene 43.3 33.5 27.6 26.2 19.7 148 11.5 10.5 Cross-linked Polyethylene 118.1 116.8 99.7 101.8 103.7 112.5 1348 144.0 Total Sold per Year 171.2 165.7) 141.1 = 136.2 130.0 132.2 150.9 158.1 Total footage of plastic tubing sold in Switzerland Material 1983 1984 1985 1986 1987 1988 1989 1990 Polybutylene 8.2 7.2 6.6 6.6 7.2 5.6 4.9 3.0 Polypropylene 11.8 12.5 12.5 9.8 9.8 9.5 6.6 3.9 Cross-linked Polyethylene 15.4 148 171 17.7 190 184 19.0 20.7 Total Sold per Year 35.4 345 362 341 36.0 335 30.5 27.6 Total footage of plastic tubing sold in Austria Material 1983 1984 1985 1986 1987 1988 1989 1990 Polybutylene 2.6 4.9 4.9 4.6 4.3 4.6 3.9 3.9 Polypropylene 6.2 3.3 2.6 2.6 2.6 2.0 1.3 1.6 Cross-linked Polyethylene 5.6 4.9 5.6 5.6 79 9.2 9.8 9.8 Total Sold per Year 14.4 13.1 13.1 13.1 14.8 15.8 15.0 §=15.3 Total footage of plastic tubing sold in France Material 1983 1984 1985 1986 1987 1988 1989 1990 Polybutylene 2.3 2.0 1.6 1.6 1.6 2.0 2.0 3.0 Polypropylene 5.2 3.3 3.3 3.3 3.0 2.6 2.0 1.0 Cross-linked Polyethylene 16.1 17.7 19.7 23.0 25.6 31.5 354 37.1 Total Sold per Year 23.6 23.0 24.6 27.9 = 30.2 36.1 39.4 41.1 Total footage of Cross-linked Polyethylene tubing sold in West Germany Material 1987 1988 1989 1990 Chemically Cross-linked Polyethylene (Engel Method) 49.2 45.9 443 52.5 Electronically Cross-linked Polyethylene 52.5 65.0 85.6 88.6 Note: Figures are in millions of feet ie STADLER CORPORATION * 3 Yankee Division Road * Bedford MA 1730 * Tel : (617) 275-3122 The WIPEX®*-coupling for the Wirsbo-PEX® pipe To Install R-PEX” You Need One Person and Two Hand Tools to. heat: and pressure, chemical ' resistance, : and ‘unrestricted internal flow. “The. Pipe. WiRS = 5925 148th STREET WEST + APPLE VALLEY, MN 55124 (612) 469-4800 + FAX (612) 469-1657 EET e REGINA WIRSBO R-PEX Single WIRSBO R-PEX SIZING INFORMATION Part Pipe Pipe ID Pipe OD Jacket Insulation Weight Coil Min. Bending Number Size inches inches OD/inches Thickness Ib/ft. Length Radius (25002 x 0.8032 0.9843 5 1.7" 0.7 650' 0.7" y “525003 1" 1.0236 1.2598 5 1.6" 0.8 490° 0.8" 525004 1%" 1.2835 1.5748 6 2.1" 1.4 325° 1.0 525005 1%" 1.6063 1.9685 6 1.9" 1.5 325° 13° 525006 2" 2.0236 2.4803 6 1.6" 1.7 325° 1.6 525007 2K" 2.4095 2.9528 8 2.1" 2.6 160° 2.6' 525008 3" 2.8976 3.5433 8 1.8" 3.0 160° 3.3" WIRSBO R-PEX Twin Part Pipe Pipe ID Pipe OD Jacket Insulation Weight Coil Min. Bending Number Size inches inches OD/inches Thickness Ib/ft. Length Radius 525102 2x%" 0.8032 0.9843 6 17" 1.3 650" 1.6 525103 2x1" 1.0236 1.2598 6 1.4" 14 490 2.0" 525104 2x1%" 1.2835 1.5748 6 1.1" 1.6 325° 2.6 525105 2x14" 1.6063 1.9685 8 1.4" 25 160 3.3 The R-Pex carrier pipes are rated up to 200° Fahrenheit continuous working temperature and up to 100 psi working pressure. hoe The carrier pipes are fitted together using WIPEX couplings made of corrosion proof brass. Fittings are available to connect R-PEX with other types of piping; including copper and steel. Z 43 25535 3569 24H Kunststoff GmbH Ochtrup 727 POL 09.84.91 15:29 SEER fia /5 a) Kunststoff GmoH Am Langenhorster Bahnhot 2 Kunststoff Gmb, Tel: 02653/727-0 Tetetax O25SYSE59 u silt 09.04.1991 br/fr Telefax-Nr. 001 907 2582419 From: 2H Kunststoff GmbH, Ochtrup/Germany To: Polarconsult Alaska, inc., Anchorage/Alaska Attn, Earle Ausman, President Your fax dated 07.03.91 Dear Mr. Ausman, Thanking for your fax we can give you some rough information about cross~ linked polyethylene-tubing which you want to use in glycol-water heating systens. For an order of about 10.000 m of each tubing diameter/year our price =x work Germany in DM/m, for the bigger diameter without oxygene permeation inhibition will be as follows; Overpressu:¢ (bar) 4 6 10 bar diameter (mm) 20 1,16 1,71 2,38 DM/m 25 1,76 2,59 3,14 DM/m 32 2,84 4,13 5,94 DM/m 40 4,30 6,49 8,91 DM/m 30 7,26 10,07 14,52 DM/m 63 11,66 16,06 22,77 DM/m 7/4 75 16,50 22,55 32,78 DM/m oe As you know the flexibility at -40 °C will be lower than, in a temperature level higher than 0 °C and should be tested by you.. The calculation of wall thicknesses is done in that way so that temperatures of 90 °C could be possible, even for longtherm use, on that temperature level. Kunststoff Gmb) Page 2 dated 09.04.91 br/fr If this temperature level is just reached for shorttime situations and the flexibility of -40 °C is not that big question the use of special polypropylene random copolymers, especially developed for european floor- heating systems and hot water distribution system with normal temperatures in the range of 60 °C (maximum 80 °C) and possible shorttime peaks upto about 100 °C would be possible.for tubing, made out of this materials You can roughly multiply our price table with a factor 0.6, The wall- thicknesses can be calculated by using the outside-diameter and for each pressure level a certain multiplyer. Multiplyers are for 4 bar about 0.09, for 6 bar about 0.135, for 10 bar about 0,21, Wall tension will be in the range of 2.0 - 2.2N/mm’. For the polypropylene-tubing you can use welding equipment and normal polypropylene-fittings which could be delivered by an Austrian partner of us. For the crosslinked polyethylene-tubing using a silane crosZlinking system, metallic fittings are necessary, which could be possibly bought from an Italian company named Opal Armaturen, For chemical processes etc. with hot or aggressive medias we can deliver tubing for a PVDF-system for a maximum temperature upto 140 °C, shorttime peak 150 °C, For those temperatures factor by using our price table will be about 10 - 11, If the temperature level is not higher than 80 - 100 °C wallthickness and price-level could go down to a half or 1/3 for this material PYDF. For very aggressive medias, each types of acid etc. and temperatures on a maximum level between 150 - 170 °C also for applications in special heat exchangers, we are able to deliver PFA~tubing with a certain TUV-acceptance. Price-level can be calculated by using our polyethylene-pricelist and mulciplyer about 25, Maximum diameter is about 40 mm. We hope that you can find a market in the US or in Canada for our products. With best regards 2H Kunststoff GmbH Siegfried Br, SalepMang upto 220 °C and gases generated by you some more detailes, if you are If you could combine the plastic. Made of an aluminum floors or ceilings - you will soon find strength of metal and the dura- tube laminated to interior and kKitec in many demanding appli- bility of plastic in one pipe, many exterior layers of plastic, Kitec cations. Hot and cold water 7 of your piping problems would be provides a composite piping distribution, water service, under- solved. Kitec is the pipe you have system for a wide range of floor heating, air conditioning been waiting for. applications, often beyond the systems, domestic gas, com- Kitec is a multi-purpose pressure scope of metal or plastic alone. pressed air, industrial process pipe which uniquely unites the Indoors or outdoors, encased in piping, and shielded electrical advantages of both metal and concrete or concealed in walls, conduit, are all potential Kitec, a revolutionary pipe, offering the best of both worlds. kitec * is @ trademark of Kitechnology B.V. used under license by Scepter Manufacturing Co. Ltd g temperatures are possible. KITEC GREY APPLICATIONS _ : Electrical conduit (shielded), electronics and telecommunications trunking, reinforced conduit for cables MATERIAL PE - AL- PE CHEMICAL RESISTAN Non-corroding, resists most acids salt solutions, alkalies, fats and oils OPERATING TEMPE Continuo ES ‘© maximum 60°C SUSPENSION DISTA Horizontal 3.5 ft. Vertical 7 ft. FITTING COMPA\ v Most plastic fittings used in electrical Nstallations THERMAL EXPANSION CO 1.3 x 104 in./in./°F cope —-1014._:1216. 1620 2025 NUM 3/8") (3/4), ") AVG. INTERNAL DIAMETER ) (1/2") 415 490 .627 .792 EXTERNAL DIAMETER 551.630 .787 .984 (in.) MIN. BENDING RADIUSSD =. 2.76 3.15 3.94 4.92 (in.) COMPOSITE WALL THICKNESS (in) 071 .075 .089 .089 WEIGHT 7 | | PER FOOT 054 .066 .097 .124 (Ib.) VOLUME PER na FOOTLENGTH 005 .008 .013 | .021 (gal.) t EMA ee ota KITEC ORANGE APPLICATIONS Hot water, central heating, underfloor heating, cold water. industrial process piping MATERIAL PEX - AL - PEX CHEMICAL RESISTANCE ] Non-corroding, resists most acids, salt solutions. alkalies, fats and oils OPERATING TEMPERATURES Continuous to maximum 82°C OPERATING PRESSURES 125 psi SUSPENSION DISTANCE Horizontal 3.5 ff. Vertical 7 ft THERMAL CONDUCTIVITY 3.12 B.T.U. in. /ft.2/hr./°F THERMAL EXPANSION | KITEC BLACK APPLICATIONS Solar heating, outdoor piping, hot water heating. underfloor heating, cold water, air conditioning, compressed gas MATERIAL PEX - AL - PEX CHEMICAL RESISTANCE Non-corroding, resists most acids salt solutions, alkalies, fats and oils OPERATING TEMPERA™ Continuous to maximum 82°C OPERATING PRESSUR! SUSPENSION Horizontal THERMAL CONDUC THERMAL EXPANSION 1.3 x 104 in./in./*F LSE DISTRICT FAKFEAT 1014 1216! 1620. 2025 CODE 1014 1216 1620 2025 (3/8) (1/2) | (3/4) (ry NUMBER 3.8) (1/2) (3/4) (1) AVGINTERNAL < | DIAMETER 415 .490 627 .792 490 .627 .792 in.) 551.630 | .787 984 MIN BENDING RADIUSSD =. 2.76. 3.15 | 3.94 4.92 (in.) 075 | .089 | .089 066 | .097 |.124 FOOTLENGTH .005 .008 | .013 | .021 (gal) SRE TE Se Mh oR x EXTERNAL DIAMETER 630 ..787 .984 (in.) 7 a MIN.BENDING RADIUS 5D 2.76 3.15 3.94 4.92 089 .089 COMPOSITE WALL THICKNESS (in.) 071.075 054 .066 .097 ..124 005.008 | .013 ;.021 WEIGHT PER FOOT (ib.) ‘VOLUME PER FOOT LENGTH (gal.) /O Scepter KITEC GREY FOR SHIELDED GRIS POUR CONDUITS ELECTRIQUE: ELECTRICAL CONDUITS, (BLINDES), JONCTIONS ELECTRONIQUE! AND TELECOMMUNICATIONS ET TELECOMMUNICATION: KITEC PE-AL-PE TUYAUX KITEC PEHD-ALU-PEH SIZE PRODUCT CODE PRICE PER 100 FT. PART NUMBER COIL SIZE ven aes DIMENSION CODE DE PRODUIT PRIX AU 100 PIEDS WO. DE PIECE CFROULERU AOULEAURS. 3/8” 1014 69.50 3700314600 600’ 32 LBS. 1/2" 1216 78.95 3700414500 500’ 34 LBS. 3/4” 1620 105.50 3700614400 400’ 40 LBS. 1" 2025 127.85 3701014250 250' 32 LBS. “FIRST TWO DIGITS OF THE PRODUCT CODE REPRESENTS THE INTERNAL DIAMETER EXPRESSED IN MILLIMETRES “LES DEUX PREMIERS CHIFFRES INDIQUENT LE DIAMETRE INTERIEUR EN MILLIMETRI “LAST TWO DIGITS OF THE PRODUCT CODE REPRESENTS THE OUTSIDE DIAMETER EXPRESSED IN MILLIMETRES “LES DEUX DERNIERS CHIFFRES INDIQUENT LE DIAMETRE EXTERIEUR EN MILLIMETAL ORANGE FOR HOT WATER, UNDERFLOOR ORANGE Pour EAU CHAUDE, CHAUFFAG HEATING, AND AIR CONDITIONING SOUS PLANCHER ET AIR CLIMATIS KITEC PEX-AL-PEX TUYAUX KITEC EN POLYETHYLENE RETICULE - ALU - POLYETHYLENE RETICUL SIZE PRODUCT CODE PRICE PER 100 FT. PART NUMBER coIL size Pen can aa: DIMENSION CODE DE PRODUIT PRIX AU 100 PIEDS NO. DE PIECE cree Ronnies 3/8" 1014 76.80 3700325600 600’ 32 LBS. 1/2 1216 84.40 3700425500 500’ 34 LBS. 3/4” 1620 116.85 3700625400 400’ 40 LBS. 1" 2025 139.65 3701025250 250' 32 LBS. BLACK FOR SOLAR HEATING, NOIR POUR CHAUFFAGE SOLAIRE AIR CONDITIONING, AND AIR CLIMATISE E OTHER OUTDOOR APPLICATIONS AUTRES APPLICATIONS EXTERIEURE KITEC PEX-AL-PEX TUYAUX KITEC EN POLYETHYLENE RETICULE - ALU - POLYETHYLENE RETICUL SIZE PRODUCT CODE PRICE PER 100 FT. PART NUMBER COIL SIZE Pen connas. DIMENSION CODE DE PRODUIT PRIX AU 100 PIEDS NO. DE PIECE ue) panne: 3/8” 1014 79.80 3700326600 600’ 32 LBS. 1/2" 1216 88.60 3700426500 500’ 34 LBS. 3/4” 1620 119.40 3700626400 400’ 40 LBS. 1" 2025 143.75 3701026250 250’ 32 LBS. Page 2 // sot The i.c.m@ller insulated pipe consists of an internal metal carrier pipe insulated with rigid polyurethane foam, a plastic material with very high insulation properties. The polyurethane insulation is protected externally by a very strong impact-resistant outer pipe of polyethylene (HDPE). During manufacture the carrier pipe. the rigid polyurethane foam, and the outer casing are securely bonded to- gether. Extensive tests have shown that the insulation of i.c.mgller district heating pipe has sufficient compressive and shear strengths to resist any long term harmful effects under- ground. 8 5/8” (220 mm) A I length delivered Steel pipe The steel pipe in the i.c.m@ller district heating pipe is of the welded type with dimensions in accordance with ISO 4200. As a standard feature, all steel pipes are supplied in a killed steel quality RSt 37-2 according to SS 141312 with a tensile strength of 350-480 MPa and a yield strength of min. 235 MPa. Welding factor V=10 Technical requirements are in accordance with approved US standards and the quality is documented with works tests certificates. Bevelled ends according to ISO 6761 Hydrostatic pressure test: min. 50 bar with cold water. Outer surface finish: grit blast cleaning to grade BSa 1 according to SS 055900. Foam insulation The highly efficient insulation layer of rigid polyurethane foam is formed by combining two components. A dedicated production plant helps insure the manufacture of a com- pletely homogeneous foam. The moulded hard polyurethane foam, consisting of 90-92% closed cells has the following charateristics: LLL general Average density: 5.0-6.2 lb/ft? = 80-100 kg/m? Compressive strength: 71.0-85.0 lbf/in* = 500-600 kPa pH-value: 9.4+ -0.3 Continuous operating temperature: 266°F (130°C) Allowable peak load temperatures, depending on the actual temperature life curve of the district heating system, can be determined on the basis of the i.c.mgller life calculation pro- gram. For instance. short peak loads of 284°F (140°C) can be permitted. Coefficient of thermal conductivity: 0.05 BTu/ ft.h.°F (0.013 Keal/ ft.h.°F) at 122°F = 0.027 W/mK ((0.023 keal/ m.h.°C) at 50°C (new value)). Outer casing The outer casing of hard polyethylene, HDPE, is manufactured in our factory according to strict tolerance and test requirements. The internal surfaces of all HDPE casings are subjected to corona treatment during produc- tion for better bonding. alarm wires t foam insulation carrier pipe casing Material: Hard polyethylene (HDPE) with density 0.3 Ib/in* (0.96 g/cm?) Elongation at break: Min. 350% Yield stress: 20 MPa (2845 Ibf/in? (200 kp/ cm’*)). Coefficient of thermal expansion: 3.6-10* in.in!°F! (2.0-107 cm.cm™K") The i.c.mgller pipe is also supplied with copper alarm wires, moulded into the foam insulation, for use with an electronic surveillance system which combines fault indication with an im- mediate localization of that fault. Further data of the i.c.mgller pipe can be found on the following pages of this section. a malar ale fradaricia AL tel 485094711 108A 11 [2 culations if the joint Insulation should not be carried out during wet weather unless the pipes are under cover. If the . pipes are moist or wet prior to insulation they ach dimen- can be dried off using a soft gas flame. he easiest a : the pipes ) 4°/7.87" vated, so r of the If the joint area has been under water before the joint couplings have been fitted, the wet polyurethane foam should be removed from the pipe ends using a sharp knife. re the ‘and all /Z 3.2.1 aper lock joint Cc Sealing compound is applied to the lower joint half, which is pressed against the outer casing and supported with wedges. The sealing com- “culations pound is applied to the polyethylene casing at the points of contact between the joint coupl- ing and the outer casing. 6.3 | 7.87 | 8.86 | 9.84 | 12.4 160 | 200 | 225 250 | 315 1034 | 1036 | 2036 | 1037 | 1038 2.5 2.7 3.0 3.2 3.6 8'2" | 810" =| 9°10" _10'6" 1110” ‘he upper joint part is then placed into posi- ion. The two joint parts are pressed together nd the four taper locks are fitted loosely. ote: One of the taper locks with an anode for ithodic protection must be fitted. moller a/s fredericia dk tel. 455926211 1986.11 / 4 APPENDIX C Heat Transfer Calculations Y-AXIS (#t.) ~2.0 -8.0 -16.0 -32.0 ~40.0 -48.0 GRID DATA FILE GRIDPLT.FOR b:nome006. grd Version 1.0 T ] T 0.0 8.0 16.0 X-AXIS (+#t.) 24.0 FIGURE i. CNTRPLT V1.0 Frost Front: b:nomeO006. unf Grid Gutline: b:nome006. ot1 ° Early Jan. Model Time= Early May Model Time= 204S4.01 #5 o _ es 4 a + S . a —————————— 9° S 74 —+——s- _I™ -M apa ane a a o «6 t T T T T a 1 0.0 4.0 8.0 4.0 8.0 12.0 16.0 Width (#t.) Width (#t.) °o Farly Jul. Model Time= Early Nov. Model Tims= 24837.05 35 Oo _ 37 we) = £ ||© a aaa’ aa a a a 2 . #4 -~™ a a a s a a a oO 3 | i T T a TT T Tt 0.0 4.0 8.0 4.0 8.0 12.0 16.0 Width (t.) Width (#t.) esuoe RA