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1 Lets Talk Insulation 'Insulation' as a term is widely used and interpreted, but when we do speak of it, we are mostly concerned with insulation against the heat & cold. Thermal Insulation, in most sectors of industrial and allied processings, is not only of technical, but also of economic importance. In view of the Energy situation today, the economic aspects become more and more important. By far, the best insulant known, is air, 'still' air, which does not transport heat. The object of insulation, is therefore to entrap air, as for example between fibres, or in cells of some cellular material such as a foam. To maintain the insulation efficiency, this air should not be displaced by water. The warmest clothing is of little use, if it is wet, or even a little damp." The same applies to insulants in industry. inside outside inside outside The insulation material simply HAS to be kept dry, always. Most conventional insulating materials, such as for example, cork, mineral wool, glass fibre, expanded Polystyrene viz; Thermocole, Phenolic foams, etc have very poor physical and mechanical properties, and as such have always to be used in conjugation with some protective physical barriers such as metallic claddings, vapour & moisture barriers, etc. In order to maintain their insulative characteristics. However the failure rate of even such systems have been very high chiefly due to their poor physical & mechanical properties. In the case of cold insulation, additional protection is necessary to prevent t h e e n t r y o f w a t e r a n d condensation, which is very damaging to the system, in terms of efficiency, operating costs, and performance. " Greater the difference between the desired process temperatures and the ambient, greater the energy demands, and more power is consumed to compensate for the heat transfer losses. Consequently, more critical the role played by the insulant." A logical step therefore, is to examine the possibility of improving the efficiency of the Insulant. Technically, the easiest way to accomplish this would be to increase the insulation thickness, but this is not always an economically acceptable solution. " Insulation costs money, and more insulation costs more money." The task is therefore to examine and improve on the efficiency and effectiveness of the insulant without incurring much additional capital costs. This would directly increase profitability through energy savings and indirectly, improve performance, and extend greatly the life of equipment. Let us now consider RIGID POLYURETHANE FOAM, one of the most cost effective insulants known in the world today. Regd. Office: : 17-5 Gitanjali Kunj, 5 Dr. Ambedkar Road, Pune INDIA

2 Properties of Rigid Polyurethane Foam In all areas of use, insulation techniques and materials have to be improved essentially for economic reasons and in the light of statutory requirements. Insulation in all fields, is today dominated by the need to save energy, ensure physical reliability, and to realise general economy. For this reason insulating materials and systems are now required to have a level of properties previously demanded only under extreme conditions. ECONOMICAL INSULATION WITH RIGID POLYURETHANE FOAM. Rigid PU Foam displays a characteristics closed cell structure and is rigid in nature. The cells contain trichlorofluoromethane, a Flurocarbon gas, which has a characteristic low thermal conductivity. This results in very high insulating capacities, and low densities. This feature makes PU Foam suitable for all specialised and routine insulation applications. Rigid PU Foam has the highest insulating capacity of all insulating materials now in common use, and it offers an economical and technically sophisticated solution to virtually every insulation situation. Rigid PU foam is also characterised by the following properties, Suitability for service over a wide temp range (-200ºC to + 10ºC) Good rigidity Optimum ageing resistance C h e m i c a l a n d b i o l o g i c a l resistance Can virtually be tailored to suit the insulating requirements. Rigid PU foam, is therefore one of the few insulating materials whose properties meet all the physical e c o n o m i c a n d s t a t u t o r y requirements for the building industry, civil engineering, refrigeration and air conditioning industry. INSULATING CAPACITY Rigid PU foam, has the lowest thermal conductivity of all known insulating materials in the world. This makes its insulating capacity very high even in thin sections. Thermal conductivity value is an extreme low of W/m ºk. By virtue of this, rigid PU foam can be used foe all specialist insulation work where optimum physical values and high energy savings are required for technical and economic reasons. The foam can be used over a wide temperature range, with virtually no detrimental effect on its insulating capabilities, right from + 10 C upto C -200ºC upto + 10ºC, and special formulations can even cater for temperatures as high as +150ºC. WATER VAPOUR DIFFUSION Rigid PU foam has excellent water vapour diffusion resistance. This means that you are guaranteed of a minimal condensation effect in applications such as in refrigeration, wherein such effects can lead to a serious breakdown of the thermal conductivity characteristics of the insulant, and lead to heat losses, poor performance of equipment and consequentially higher power demands. Water has a thermal conductivity more than 20 times than that of a Rigid PU foam. The amount of water absorbed is inversely proportional to the percentage of closed cells of the foam. Rigid PU foam has a closed cell structure. Proportion of closed cells is nearly 95% Water penetration is approx 2% by vol (which is extremely low) whereas in the case of Phenolic foam it is 10%-quite high comparatively. Regd. Office: : 17-5 Gitanjali Kunj, 5 Dr. Ambedkar Road, Pune INDIA

3 FIRE SAFETY Rigid PU foam can be made flame retardant easily,& can compare with flame retardant characteristics of special grades of expanded polystyrene. The foam will not burn readily, & will not support a fire. Unlike expanded polystyrene viz. Thermocole & some other insulants, it does not drip or melt on exposure to intense heat or fire, and as such is quiet safe in use. A required mandatory practice is never to leave any bare exposed foam surfaces. Exposed surfaces are always covered with facia materials such as steel, plaster board, fire board, ply, etc and this contributes further to the safety of the material in use. MECHANICAL Since the density of Rigid PU foam can be controlled, and the foam being basically rigid a wide range of thickness can be selected to suit the insulation requirements as well as to achieve a variety of loading patterns to suit design criteria. From slabs that can be walked on, to self supporting designs. The foam offers excellent compressive strength, and this too can be tailored to suit requirements. The foam is not brittle like Phenolic foam, and resists fracture. Having kg excellent Impact resistance, and a not brittle nature, the foam has excellent crack resistance and will not splinter, or split. This is an important characteristic, as this greatly reduces breakage, waste, and eases handling and fabricating procedures. Fracture on Impact like in case of Phenolic foams will other wise lead to a direct cold bridging and costly reworking and maintainance, inspite of protective claddings being used. The foam has excellent dimensional stability and accuracy even at extremes of temperatures and displays a good friability resistance. CHEMICAL RESISTANCE Unlike expanded polystyrene viz; Thermocole, Rigid PU Foam is largely resistance to solvents, plasticizers, fuels, mineral oils, dilute acids, alkalis, exhaust fumes, and aggressive industrial atmospheres encountered in practical service. The foam itself is non reactive with other materials, and contains no corrosive substances. It is perfectly safe to use for food preservation applications, and is non toxic. BIOLOGICAL RESISTANCE The foams resistance to fungii & microbes makes Rigid PU foam rot and decay resistance. The foam also resistant to root penetration. The absence of any health hazards or odour permits the manufacture of insulation systems to satisfy requirements such as the refrigeration sector and food preservative industry, where hygiene is of utmost importance. WEATHER & CLIMATE RESISTANCE Rigid PU foam has given good results for many years under extreme climatic conditions in varied environments. Even where test requirements are stringent, the foam is shown to have excellent resistance to ageing on exposure to fluctuating temperature and humidity levels without any significant impairment of its insulating characteristics or functions. Long term laboratory ageing tests have determined that the foam should easily last 20 years to 50 years, with no deterioration. This is an important point as far as economics are concerned, as though the insulation system may cost a bit of more initially, it easily pays for itself many times over, through higher efficiencies, lower power demands and better performance. Thus a cost beneficial advantage accures, when comparing rigid PU Foam Insulation to any other conventionally used insulant, like thermocole, glass wool, etc. Regd. Office: : 17-5 Gitanjali Kunj, 5 Dr. Ambedkar Road, Pune INDIA Tel.: +91 (020) , Fax : + 91 (020) info@deltafoams.com

4 By virtue of its low specific gravity, rigid PU foam is easy to transport, lift, assemble, and fabricate. All types machining operations can be performed efficiently, accurately and quickly using appropriate tools. This makes p recision i n sulation economically feasible even within intricate dimensioning in inaccessible places. The foam can be sawn, drilled, cutnailed, bonded etc. easily. Our slabs, sheets, and blocks, can thus be easily used, converted, fabricated, or tailored to suit the insulation needs of intricate cavities to even the large needs of continuous roofings, and surfaces such as of storage tanks, pipelines, wineries, environmental control applications, etc. BUILDING INDUSTRY Flat and sloping roofs insulation sealed with bitumen or plastic sheeting, terraces, overdeck and underdeck applications using slabs, or sheets, exterior wall insulation, curtain walling, panellings, walling blocks etc. Ceiling and floor insulation and sound proofing, decorative panellings, attics, facades, pipes sections etc. Insulating slabs for the animals husbandry sector as well for poultry sector. TECHNICAL INSULATION AND BUOYANCY Refrigerated food preservative sector, freezers, walk-in-coolers warehouses, refrigerated containers, trucks, boxes, etc. filled with insulated slabs, etc. Industrial plant insulation, pipe insulation, for hot and cold media, storage tank insulation, fermentors, breweries, fisheries, continuous Installation And Uses process industries where close environment control is necessary such as in the textile sector, humidity and moisture control applications, etc. Chemical plants, oil tanks, drying plants, grain silos, and warehouses seed germination units, environmental chambers, dairy industry, tanker insulation, etc. Air conditioning duct work, centralized and de-centralized units, A/C plants, ventilation ducts, hot and cold water tanks, storage reservoirs, solar panels, and appliances, solar dryers and various other appliances working on non-conventional energy sources etc. Due to the exceptional buoyancy characteristics of this material, it is widely used in the boat building industry. The non-absorbent nature of this material coupled with its exceptional buoyancy factor and lightness makes it suitable for filling of the buoyancy tanks, and hull structures of boats, ships, barges, fishing vessels, etc. In this applications rigid PU Foams has unique advantages, and is widely used in life raft construction and for the fabrication of buoys and life vests, etc. Regd. Office: : 17-5 Gitanjali Kunj, 5 Dr. Ambedkar Road, Pune INDIA Tel.: +91 (020) , Fax : + 91 (020) info@deltafoams.com

5 mm 8-40 kg/m 2.75 mmpolysterene. (Common Thermocole is kg/m only.). 45 mm Mineral wool mm Cork mm Fibreboard mm Softwood mm Concrete blocks mm Brick work 2 Equiv Thickness mm Thermal Conductivity W/m ºK at 10ºC Dimensional Stability P P F F P G Water transmission H H H F F P Heat resistance G G G P G G Resistance to interstitial condensation P P P P F G Compressive strength P P F P P G Friability resistance F P G Fire Characteristics F F P P G F Abrasion Resistance - - F P P G Resistance to fracture G P P Resistance to rot P P P P G G Resistance to fungii & bacteria P P P P G G Resistance to vermin P P P P G G Buoyance characteristics P P F F F G Useful Life P P F F F G Comparison of characteristics of various insulation materials Rigid Polyurethane foam is the most efficient thermal insulation material in the world today. In the density range of 5-40 kg/m. the foam posseses several valuable properties, such as, rigidity, dimensional stability and low water vapour permeability. With extremely low thermal conductivity values, the foam is suitable for virtually any insulation application from -200 deg. C to + 15 deg. C Laboratory ageing tests suggest a useful life of well over 20 years. H - High G - Good F - Fair P - Poor Mineral Wool Glass Fibre Cork Thermocole Expanded kg/m Phenolic Foam Rigid Polyurethane 2-40 kg/m Regd. Office: : 17-5 Gitanjali Kunj, 5 Dr. Ambedkar Road, Pune INDIA