ISOVER for Technical Insulations

Transcription

1 Technical Insulations ISOVER for Technical Insulations Information for designers and assembly companies The widest offer of thermal, acoustic and fire insulations

2 TABLE OF CONTENT TABLE OF CONTENT 2 PROPERTIES OF ISOVER PRODUCTS 3 Basic functions of technical INSULATIONS 5 Heat flow transmission 6 insulation system design 7 General 7 Insulation thickness calculation 7 Insulation desigh criterion 7 Parameters influencing insulation thickness design 7 Economic thickness 7 Maximum service temperature 9 Fire PerformANCE 10 fire protection design for ventilation DUCTS 11 Legislation 11 Maximum duct sizes 11 Acoustic PerformANCE 12 Sound Absorption 12 Absorptive structures 13 Acoustics insulations 13 General rules for using Isover INSULATIONS 14 application of technical INSULATION 15 Piping insulation 15 Ducting insulation 17 Fire protection of ventilation ducts 18 Technological appliance insulation 20 Boiler insulation 20 Chimney insulation 20 ISOVER PRODUCTS FOR TECHNICAL INSULATIONS 21 Overview of technical insulation APPLICATION 26 Technical insulation PROPERTIES 27

3 PROPERTIES OF ISOVER PRODUCTS FROM MINERAL WOOL Mineral wool insulation Isover is made from the earth s most abundant materials: rock, sand and minerals of various types. The production is based on fiberizing of molten raw materials consisting of minerals and different amounts of artificial resins. Mineral wool insulation materials are delivered as wired mats, lamella mats, slabs, blocks, pipe sections and felts. Depending upon the form of delivery, mineral wool insulations can be quilted on wire mesh, faced with foils, glass fleece or glass filament tissue or be equipped with coatings. Final Isover products have the following properties: apparent density from 25 to 150 kg/m 3 (special fire protection slabs can have density up to 200 kg/m 3 ), very good thermal insulation performance (low thermal conductivity), very good sound attenuation (high absorption coefficient), fire resistance non-combustible material, high temperature resistance (possibility of application up to a maximum surface temperature), environmental friendly and hygienic, hydrophobisation Isover insulation materials are made water repellent, long life span (material is not aging), resistant to wood-destroying pests, rodents, and insect, easy to handle, easy to cut with a sharp knife. for this purpose. Binders and greasing agents in mineral wool products dissolve and evaporate in areas with temperatures higher than 150 C. As the temperature falls in the direction of the insulation s cold side, the binder remains unchanged in the greater part of the material. In the outer areas, colder than 150 C, no dissolution and evaporation take place. Isover is part of the Saint-Gobain group, leaders in the design, production and distribution of materials for the construction, industrial and consumer markets. With a presence in over 50 countries, the group s global reach allows us to draw on unrivalled financial and technological resources to meet the changing needs of customers and communities in the 21st century. In the Czech Republic Isover has a modern stone wool plant in Častolovice, Trade Headquarters is in Prague. Thermal, acoustic and fire protection insulations have been produced in Častolovice for more than 40 years. Our company offers a complete range of insulation materials from both stone and glass wool. Thus we can offer you the optimal product for any industrial application. You will find the best solution with us. The Isover product range provides fire safe thermal and acoustic insulation solutions in many applications, including HVAC, original equipment, transport and for tanks and storage vessels. The range of high quality products has been designed to be effective in both performance and cost, while providing ease of installation. Each product is engineered to fulfil specific performance criteria. Maximum surface temperature (MST) is dependent on the apparent density (the higher the density, the higher MST and better thermal performance at high temperature surfaces). Mineral wool insulations have a melting point higher than 1000 C. For outdoor application metal steel jacketing is required. If a product is with an aluminium facing, then the surface temperature must not exceed 100 C on the facing; proper thickness of insulation must be designed 2-3

4 AS quality Corrosion of stainless steel surfaces under insulation is an often discussed issue. Highly alloyed austenitic steel (alloyed by chrome, nickel and molybdenum) are predisposed to tensile stress corrosion (stress corrosion cracking), which is caused by chloride ions. Austenitic is a description of crystalline steel structure, therefore identified as AS. Chlorides with water (well-known is classical salt) attack steel surface and cause cracks in the material. With increasing surface temperature the danger of stress corrosion cracking is raised. To minimise this danger, mineral wool insulations in AS quality are available for this application. Standard AGI Q 132 determines maximum content of chloride ions of 10 mg in 1 kg of the insulation material. Mineral wool insulations may be used for insulating objects made of stainless austenitic steels if the content meets the requirement. Isover stone wool technical insulations meet the requirement of AGI Q 132. Thermal conductivity One of the most important parameters of insulations is their thermal conductivity named lambda value λ [W/ (m.k)]. Thermal conductivity measures the capacity of a material to lead or to resist heat transfer. The smaller the lambda value, the better the thermal insulation. The thermal performance of mineral wool is achieved through the entrapment of air within the material. Its thermal conductivity does not deteriorate over time. For slabs, mats, felts and loose mineral wool, the thermal conductivity is determined in the hot box tester according to EN The determination of the thermal conductivity of sections is in the pipe tester according to EN ISO For lamella mats and wired mats, the thermal conductivity is measured in the hot box and in the pipe tester. The thermal conductivity of mineral wool insulations has to be determined up to the maximum service temperature (hot face) as a function of the mean temperature (arithmetic mean between object and surface temperature). The thermal conductivity varies with temperatures and with densities. The higher the density, the higher the thermal performance at high temperature surfaces. In our product data sheets declared lambda-values λ D are used; these values are fulfilled within every product. A designer will be on the safe side when using our declared lambda-values. That means allowances for workmanship, spacers and supporting constructions are made. Possible inaccuracies caused by calculation equations can be eliminated. Melting point of mineral wool products The melting point of mineral wool is determined according to DIN 4102 part 17. It is a parameter for the durability of mineral wool insulations in building components in case of fire. It must not be confused with the maximum service temperature and has no relation to the service temperature. Mineral wool insulations have the melting point higher than 1000 C, usually in the range from 1200 to 1600 C. Maximum service temperature Maximum service temperature according to EN (for wired mats, lamella mats and slabs) and EN (for pipe sections) ranging from 250 to 700 C. MST for various products can be found in a Product data sheet or at the end of the catalogue in the chapter Isover Products on page 23. Fire resistance Mineral wool products Isover are completely noncombustible; they resist to high temperatures and thus prevent fire spread. The classification levels according to EN are A1, possibly A2 for materials with a facing. Acoustic properties Isover mineral wool products have a fibre structure and therefore reach excellent noise attenuation, for example from HVAC services (pipework, ductwork and air handling equipment) and other services. An absorbent layer of mineral wool has the best absorption capacity in the medium and high frequencies (under such conditions it can have absorption coefficient up to 98 % (α = 0,95)). The absorption in the low frequencies is improved by increasing the thickness or by providing an air gap behind the absorbent layer. Resistant to biological pests Mineral wool insulation is resistent to wood-destroying pests, rodents, and insects. They are rot-proof and do not sustain growth of mould. Low thermal expansion Mineral wool insulations have almost zero thermal expansion with changing temperatures. Moisture and water repellence All Isover products are treated during manufacture with special additives, which make them water repellent. Isover products are a hydrophobic, non-hygroscopic insulation material. If Isover products get wet, they dry out quickly as a result of the open structure and its mechanical and insulating properties are unaffected after drying. For outdoor application metal steel jacketing is unconditionally required.

5 Basic functions of technical insulations The application of thermal insulation on pipe, vessels and ducts is recognized as a necessary requirement in any construction activity. The thickness and extent of insulation required has always been subject to arbitrary and imprecise decisions with little engineering or economic input. No material incorporated in a modern construction project provides the owner with as good a financial return throughout the life of the facility as does insulation. Insulations are defined as those materials which retard the flow of heat energy by performing one or more of the following functions: Energy conservation: minimizing unwanted heat loss/ gain from building HVAC systems, as well as preserving natural and financial resources. Personnel protection: controlling surface temperatures to avoid contact burns (hot or cold) maximum surface temperature criterion. Condensation control: minimizing condensation by keeping the surface temperature above the dew point of surrounding air. Prevent internal condensation in pipes. Process control: minimizing temperature change in process fluids where close control is needed. Increase operating efficiency of heating, ventilating, cooling, plumbing, steam, process and power systems found in commercial and industrial installations. Freeze protection: minimizing energy required for heat tracing systems and/or extending the time to freeze in the event of system failure. Freeze protection of vessels and tanks with various accumulated fluids or fuels. Noise control: reducing/controlling noise in mechanical systems. Fire safety: protecting critical building elements and slowing the spread of fire in buildings. The investment in insulation may protect the equipment and personnel present during the life of the facility. Proper insulation prevents condensation, chemical corrosion and excessive heat in fire hazard areas. Added human comfort provided by proper insulation in hotels, office buildings, schools or factories adds considerably to the value of the facility and productivity of its personnel. Process temperatures in heat traced piping are more efficiently maintained with proper insulation. The size of the heat generating equipment can be reduced when designed with an efficient insulation system. In some cases, insulation is essential to an industry s very existence as with the power, the process, and the cold storage. However, the most substantial return on an investment in insulation is in energy savings over a period of time. These savings are becoming more and more emphasized in the industrial insulation field as energy costs rise, coupled with the fact that industrial plants and utilities usually account for about half of the total energy consumption. Recently, the environmental impact of new, renovated or relocated industrial and commercial facilities has taken on new importance. Thermal insulation is one of the most, if not the most, significant technology used to conserve energy, thereby reducing pollution. Besides minimizing heat loss, insulation increases process efficiency, helps maintain employee safety, comfort and production. For their thermal protection of various industrial applications it is a necessity to design and use such insulation material that meet operating conditions. Isover will help you find the most suitable insulation product for given application. 4-5

6 Heat flow transmission Temperature gradient in a material (wall, pipe, insulation). Heat transfer is carried out by three heat transmission modes: conduction, convection and radiation. Conduction Heat transfers from warmer surface to colder through solid material or gas (by fibres in mineral wool insulations). The more insulant the material, the less the conduction. Convection Transfer of heat caused by air movements (because of temperature and density gradient). Hot air moves up and heat dissipates. The quieter the air, the less the convection. Convection can be natural (when calculating insulation inside the building) or forced (for calculation outside where wind blows). Radiation Each material absorbs or emits thermal radiations depending on its temperature and its emissivity. Unlike conduction or convection, heat can be transferred by radiation also in a vacuum. When radiation is absorbed or reflected, there is less thermal transfer. Measure of radiating capacity of a material is emissivity ε. Absolute Thermal insulations impede conduction, convection and radiative effects: by creating a thermal barrier against conduction, by suppressing air movements, by limiting radiative effects. Surface heat transfer coefficient Two heat transmissions (convection and radiation) influence the heat transfer coefficient α [W/(m 2 K)]. The higher the heat transfer coefficient, the higher the heat flow rate from a warm surface. Thermal transmittance Thermal transmittance (also called Overall heat transfer coefficient) U (for flat surfaces [W/(m 2 K)], for pipes [W/ (m K)]) is inverted value of thermal resistance and it takes into account the influence of all heat transmission modes (conduction, convection and radiation). For multi-layer wall: For multi-layer hollow cylinder: black body has the highest emissivity (ε = 1). Rough and dark surfaces approaches such value (for example mineral wool insulation without jacketing ε = 0.94), contrary to bright and smooth surfaces that have very low emissivity (for example polished aluminium foil ε = 0.05). For design it is necessary to take into account that covering of the bright surface with dust will increase emissivity significantly. These three transport mechanisms are applied in two very important quantities surface heat transfer coefficient α and thermal transmittance U., where: d thickness of the insulation layer [m], λ design thermal conductivity of the insulation product [W/(m K)], α i internal heat transfer coefficient (at the medium side), α e external heat transfer coefficient (at the ambient side), R thermal resistance of the multi-layer wall [m2 K/W], R si internal surface resistence [m 2 K/W], R se external surface resistence [m 2 K/W], Materials emissivity. Insulation jacketing ε [-] Aluminium foil, bright 0.05 Aluminium, slightly oxidized 0.13 Stainless steel 0.15 Aluzinc sheet 0.18 Galvanized sheet 0.26 Iron, oxidised 0.30 Aluminium, stucco-design 0.40 Brass, browned 0.42 Paint, white 0.85 PVC; paint coated sheet metal 0.90 Paint, black 0.92 Plain mineral wool 0.94 Internal surface resistence of the inner side of the pipe or wall is very low and therefore it is often neglected in practical engineering calculations. Only in air ducts it is necessary to calculate it. Details for calculations can be found in the standard EN ISO

7 insulation system design General An insulation system is the combination of insulations, finishes and application methods which are used to achieve specific design objectives. Among these are: Energy savings. Reduced operating costs. Condensation control. Chemical compatibility with the metals being insulated, the atmosphere to which the system will be exposed and the various components of the insulation system itself. Protection of mechanical and insulation systems from mechanical abuse and atmospheric damage. Personnel protection. Fire protection. Sound control. Future requirements for access to piping, fittings, etc. Accommodation to limited clearances or work space. the radiation exchange with the surroundings (often including a great variety of interest). For the calculation of dew formation, variability of the local humidity is an important factor. Insulation desigh criterion Apart from a choice of suitable insulation material for given application it is essential to design proper insulation thickness. It can be determined from two points of view: Heat loss minimalisation, it means reaching the highest possible economic savings (ideally to calcutate economic insulation by so-called optimalisation). Maximum surface temperature (personal protection against burn). It is usually prescribed by national legislation. Usual maximum surface temperature is 50 C if the surrounding air temperature is 25 C. If the air temperature is different, temperature difference between surface and surrounding air should be up to 25 C. Outdoor piping shall be controlled for maximum surface temperature every time for summer period (in the Central Europe calculation air temperature is 30 C). In boiler rooms, surrounding air temperature is minimally 35 C. Parameters influencing insulation thickness design While there are several choices of insulation materials, which meet basic thermal and cost-effective requirements of an installation, choices become more limited with each additional design objective that comes into play. Insulation thickness calculation When calculating the thickness of the insulation it is essential to put in appropriate boundary conditions. lt should be noted that the steady-state calculations are dependent on boundary conditions. Often a solution at one set of boundary conditions is not sufficient to characterize a thermal system which will operate in a changing thermal environment (process equipment operating year-round, outdoors, for example). In such cases, local weather data, based on yearly averages or yearly extremes of the weather variables, should be used for the calculations. The heat flow through a surface at any point is a function of several variables which are not directly related to insulation quality. Among others, these variables include ambient temperature, movement of the air, roughness and emissivity of the heat flow surface, and Heat flow from the insulation surface is a function of several parameters which do not relate directly to the quality of the insulation. Here are several parameters that influence design: thermal conductivity of the insulation material, medium temperature, ambient temperature, external heat transfer coefficient. Economic thickness The most substantial return on an investment in insulation is in energy savings over a period of time. Thermal insulation is one of the most, if not the most, significant technology used to conserve energy, thereby reducing pollution. Rising energy costs guarantee an increasing return on any investment made in insulation. In fact, it costs less to insulate, than not to. In the case of steam process and heat, the difference in capital investment necessary to provide equipment for the extra steam capacity needed on underinsulated systems and that investment necessary to insulate plus the cost of insulation, still represents a significant capital investment savings. That insulation saves money is not the issue here. The issue is how much. 6-7

8 Economic thickness calculations are based on the law of diminishing returns. Because no insulation material can completely stop the flow of heat, each increment of insulation added to the thickness saves only a percentage of the heat which has escaped through the underlying insulation. Therefore, each increment of insulation saves less than the one before it and must be evaluated against the cost of installation to determine if it is a good investment. It is possible to determine how much insulation applied to a given system will repay its initial costs in a specified time. This point is reached when the cost of the last incremental of insulation added is offset by the savings generated by that increment. Refer to the stetch on the left. The vertical scale is the annual cost. The horizontal scale is insulation thickness. As the insulation thickness increases from 0, the cost of heat loss through the insulation decreases. Note that this cost (line B) tends to approach a horizontal line at high thicknesses. As the insulation thickness increases, the cost of the insulation also increases (line A). The total annual cost at any insulation thickness is the sum of the cost of the insulation and the cost of the lost heat (line C). Line C goes through a minimum value of total annual cost at the Economic thickness. Cost of insulation This factor is derived from computing a unit installed price of insulation with the total cost annualized over the project s life. The unit installed price is a combination of the cost of materials, cost of labor and worker productivity. This is a sensitive variable in the economic thickness calculation. Only the roughest of regional averages are available. As a result, care must be taken not to perceive these estimates as fixed budget prices used for installing insulation. Material prices are related to the volume and cost of the insulation, jacketing, securement, finishing, and structural support material used. Also included in this figure are storage and handling costs to the contractor. Labor costs vary regionally, and include wages, fringe benefits, per diem and travel expenses, as well as overhead and profit. Labor production varies with pipe size, complexity, number of layers necessary, accessibility of piping and surfaces, type of materials used, and general working conditions. Other costs involve the job size and increase with the magnitude of the job. They include the preparation scaffolding, cleanup, and tear-down costs, supervision costs, and general overhead. With thicknesses less than the economic thickness, the total annual cost is higher because of the higher value of the cost of lost heat. With thicknesses higher than the economic thickness, the total annual cost is higher because of the higher value of the cost of the insulation. In the case of computer results, each pipe size will be listed with the recommended thickness, as well as the average heat savings (as compared to a pre-listed thickness or bare surface, whichever chosen) and the present value of the heat saved. In order to use any of the available manuals, tables or computer programs, the two cost factors (cost of lost energy and cost of insulation) must be found. The following data is generally provided by the investor. Cost of lost energy This factor is derived from the combination of the rate of energy transfer, the cost of energy and the operational hours per year of the building. Computing the rate of energy transfer requires: surface and ambient temperatures, thermal conductivity of the chosen insulation, the maximum/minimum thickness of insulation to be considered, surface emissivity and last but not least consideration of surface orientation (i.e. vertical, horizontal) and wind (air) velocity.

9 IsoCal For economic thickness calculation program IsoCal can be used. The program also handles the following calculations: heat loss calculation, temperature change in pipes or ducts, temperature change in a tank, internal or external condensation, frost protection of water pipes, sound attenuation in ducts. IsoCal is a computer program for calculations of thermal insulation for building equipment and industrial installations. The program mainly calculates according to EN ISO IsoCal has been developed primarily for Saint-Gobain Isover s range of insulation products, it is however possible to perform more generic calculations. For more information about the English version 1.0 please contact your local Isover representative. maximum service temperature, no test result must display a deformation under load of more than 5 %. In data sheets of different producers (not only mineral wool) you will often find MST and value which is not measured accordance to EN This temperature is only assumed. When using such temperature there is a danger of insulation degradation, mainly insulation thickness. If mineral wool product has MST 700 or 750 C in its data sheet you can be sure that the material will not withstand such temperature without degradation of assessed properties. Such temperatures shall not be used. Producers should leave field of assumed MST and test their products to be able to use declared MST according to EN It is an outstanding improvement compared to the past, because individual products on the European market can be compared to each other according to standards valid in the EU. Slabs, wired and lamella mats Orstech are certificated according to valid European standards, they are regularly tested in testing laboratory FIW München according to VDI 2055 and AGI Q 132. Maximum service temperatures for various products can be found at the end of the catalogue in the chapter Isover Products on page 21). Evaporation of binders Maximum service temperature MST is determined in a laboratory by testing under defined conditions which are dependent upon the form of delivery and which are laid down in EN (for wired or lamella mats, slabs and felts) and EN (for pipe sections and segments). MST is determined by establishing the temperature and time related decrease in thickness in one-sided heating. For the test, the sample shall take a load of 500 Pa. The sample is heated with a transient of at least 5 K/min. The hotface temperature must be maintained for 72 hours at the expected maximum service temperature. At the Binders and greasing agents in mineral wool products dissolve and evaporate in areas with temperatures higher than 150 C. Binder evaporation does not have any influence on thermal properties; only the compactness of a material is decreased. If proper underconstruction is made there is almost no danger of insulation slide down. But if too small insulation thickness or improper type of insulation is used (mostly insulation with too low density for too high temperatures) danger of binder evaporation in the whole thickness is possible with consequent insulation slide down. In this case no well made underconstruction will help. Insulation will not work any more. In the outer, colder areas, no dissolution and evaporation take place. Temperature influence on thermal conductivity for slabs ORSTECH Density influence on thermal conductivity 8-9

10 Fire Performance HEAT FUEL OXYGEN FIRE a chemical reaction involving rapid oxidation or burning of a fuel occurs only when three elements are present in the proper conditions and proportions. FUEL Fuel can be any combustible material - solid, liquid or gas. Most solids and liquids become a vapour or gas before they burn. OXYGEN The air we breathe is about 21 % oxygen. Fire only needs an atmosphere with at least 16 % oxygen. HEAT Heat is the energy necessary to increase the temperature of the fuel to a point where sufficient vapours are given off for ignition to occur. ISOVER mineral wool insulations are totally noncombustible and completely fire safe, achieving Euroclass A1 fire rating (A2 for products with facing) when classified in accordance with EN One of the most important issues studied under reaction to fire performance is the potential for flashover to occur, which can lead to a fire spreading uncontrollably. Isover stone wool is not susceptible to flashover. This is a guide to common building materials and their likely Euroclassification. Check with individual product manufactures for spedific product specifications. Reaction to fire Fire development depends mostly on room geometry and ventilation, the fuel type, the amount and surface area of the fuel. Fire is often discussed in terms of the temperature development and can be divided into different stages: incipience (ignition), growth, flashover, fully developed fire and decay. How materials behave in the early stages of a fire, from ignition to flashover (the spontaneous ignition of hot smoke and gasses) needs to be assessed at the design stage for buildings and also for plants and equipment. Euroclasses, a new European harmonised classification system for materials reaction to fire in most European countries replaced the old national standards. The Euroclass fire classification covers not only materials used in building structures, but it is being extended also to technical insulations to cover building equipment and industrial installations. This will help to compare the reaction to fire of different thermal insulation materials. The classification levels are A1/A2 (completely noncombustible) B, C, D, E and F. A1/A2 corresponds to the safest situation. E would be the most dangerous situation and F would mean not classified. Smoke and flaming droplet risk (1) In the EU classification system for reaction to fire, a construction product will be classified as Euroclass A1, A2, B, C, D, E or F depending on its tendency to burn. (2) The product testing will provide data, represented by the signs s1, s2, or s3, which indicate the tendency to release smoke. Smoke causes over 60 % of deaths in fire across the EU. The measurement of smoke release has been put into these 3 broad bands that can be translated as little or no smoke s1 - quite a lot of smoke s2 - substantial smoke release s3. (3) Some construction products, like these made of polystyrene, can melt and ignite to form Flaming Droplets. Wooden products, on the other hand, will tend to char before the char falls away as Flaming Particles to expose more material. These flaming droplets/particles will tend to initiate new fires away from the original point of ignition and must be considered when the products are used horizontally in ceiling or roof applications. The classification system ranks the level of release of flaming droplets/particles as d0 (none), d1 (some) and d2 (quite a lot). Reaction to fire Commno materials and likely Euroclass Euroclass Flashover potential Example materials A1 & A2 No Glass and stone mineral wool, concrete, brick and plasterboard B No Typically timber products C Yes 10 minutes Phenolic foam (foil faced), synthetic rubber D Yes 2-10 minutes Expanded polystyrene type A, extruded polystyrene, polyisocyanurate foam (foil faced) E Yes < 2 minutes Pylyurethane foam (laminate faced), polyisocyanurate foam (sprayed) F Yes Early failure or no data Expanded polystyrene type N, untested or fails Euroclass E

11 fire protection design for ventilation ducts Produced with the stone wool technology of Isover, fire protection system ORSTECH Protect is mineral wool that combines all the advantages of conventional thermal and acoustic insulation with top level of fire safety. Mineral wool insulations have the melting point higher than 1000 C. From the fire protection point of view products Isover are one of the safest materials. ORSTECH Protect consists of slab or lamella mat solutions, offering up to one hour fire protection for both vertical and horizontal applications of rectangular and circular ductwork systems. Passive protection of ventilation ducts is possible by two basic means: Installed a fire damper into the duct to the place of fire separation Use a fire protection insulation system, which is tested according EN and has a classification protocol in accordance with EN This second case is covered by insulation system ORSTECH Protect. Legislation Air duct, which shall resist the spread of fire from one compartment to another, is tested according to EN The standard can be applied to vertical and whereby it is possible to evaluate the ability of a tested duct to prevent fire spread due to the destruction of the duct (integrity failure E), heat transfer (insulation failure I) and prevention of the smoke penetration (smoke leakage S). Fire protection is expressed by time in minutes for which failure criteria are fulfilled. Designation itself is then done according to classification standard EN Classification states if criteria are fulfilled for fire outside (marking o i), valid for duct type A, or fire inside (marking i o) or from both directions (i o), valid for duct type B, and if this is valid for a horizontal duct (marking ho) or a vertical one (ve), or both (ve, ho). E.g. class EI 30 S ve, ho (o i) S represents duct capability to maintain integrity, insulation and smoke leakage for time period of 30 minutes under fire exposure from outside, both for vertical and horizontal positions. Maximum duct sizes Maximum size is according to EN for rectangular duct 1250 x 1000 mm and for circular duct up to diameter 1000 mm. If a duct has bigger dimensions, the classification protocol cannot be used. Detailled information aboud fire protection systems ORSTECH Protect and ULTIMATE Protect system can be found on page 18 or in system date sheets. Table 1 Cross-section of test specimen Table 2 Increase in dimensions of standard size ducts permitted under direct application Duct type Rectangular Circular width [mm] height [mm] diameter [mm] A B horizontal ducts, with or without branches, for fire inside or outside the duct. The test measures the time period for which ducts, of specified dimensions, suspended as they would be in practice, satisfy criteria when exposed to fire from inside or outside (separately). Duct type Rectangular Circular width [mm] height [mm] diameter [mm] A B This standard is used in conjunction with EN , which prescribes requirements for the determination of fire resistance of various components of building structures which are exposed to standard fire conditions. In this standard there are failure criteria 10-11

12 Acoustic Performance Transmitted energy Converted energy Reflective energy α converted + transmitted incident Noise is a sound which impacts negatively on the surroundings. Noise levels emanating from HVAC services (pipework, ductwork and air handling equipment) and other services can be significantly reduced with the use of Isover products, which will help to achieve acceptable environmental noise levels. Isover insulations are due to its fibre structure, an ideal material for sound attenuation not only for industrial application. The degree of sound insulation will depend upon the application, the thickness of insulation used and the nature of any finish used to clad over the installation. In suitable frequencies they can absorb up to 95 % of the sound energy (α = 0.95). Sound Absorption When a sound wave strikes a surface, the sound energy is broken down into transmitted energy (through the material), converted energy (usually heat) and reflected energy (back towards the source of the sound). The more absorbent the material, the less sound is reflected. That part of sound energy which is converted and transmitted is usually expressed as an absorption coefficient α. The absorption coefficient for a material varies with the frequency. An absorbent layer of mineral wool has the best absorption capacity in medium and high frequencies. The absorption in low frequencies is improved by increasing the thickness or by providing an air gap behind the absorbent layer. Examples of the effectiveness of Isover products in noise control are given in the following table. Absorptive structures The most common task in room acoustics is to attenuate or cancel some frequencies or a whole frequency band. This is possible to realise by using convenient absorptive material or structures which are frequency-dependent. In this way we can control not only absorption, i.e. reverberation time, but also suppress or completely remove unpleasant sounds. In a porous material, acoustic absorption is mainly caused by friction in pores, i.e. friction between oscillating particles and the surface of pores. Since the energy loss due to friction is proportional to the length of the path, the most absorption will occur when the porous material is placed in a position where the particle displacement is the largest (maxima displacement). When sound strikes a rigid wall like concrete, for example, a standing wave result and the maxima of particle displacement appear at the distances λ 1 /4, 3λ 2 /4, 5λ 3 /4, from the surface of a room. These are the critical distances which must be covered by adsorbers, i.e. layers with thicknesses d 1 = λ 1 /4, d 2 = 3λ 2 /4, d 3 = 5λ 3 /4. In short, an absorber with a thickeness d placed directly on the solid structure will effectively attenuate only those frequencies, where f c/4d (c is the velocity of sound 340 m/s). For example, insulation thickness of 50 mm will reliably attenuate frequencies higher than 1700 Hz, thickness 100 mm then already from frequencies 850 Hz. The higher the frequency, the shorter the wave length and better attenuation. An absorbing layer, tightly adjacent to a solid structure, has nevertheless, one disadvantage. To attenuate low frequencies it would be necessary to use very thick layers (for example for attenuation of 500 Hz a thickness of about 20 cm would be necessary). Therefore acoustic tiles can hardly attenuate low frequency noise (frequencies lower than 100 db, such as noise from discotheques). Fortunately, it is possible to avoid expensive acoustic tiles with high thickness. If we use a very thin layer and place it just in the position of the displacement maximum of a chosen frequency, this chosen frequency and its odd multiples will be attenuated. Acoustic tiles thus work as a selective frequency filter. On the selective basis also other acoustic attenuators work, namely membranes, oscillating plates and resonators.

13 Acoustics insulations Isover stone wool products with a high longitudinal airflow resistance (up to 95 kpa.s/m 2 ) and uniform porosity (93 99 %) are used as sound attenuation insulations. In suitable frequencies they can absorb up to 95 % of the sound energy (α = 0.95). Sound attenuation in a construction is related to elastic properties of Isover mineral wool insulations and their low modulus of elasticity (they have low dynamic toughness and therefore they are much more suitable for acoustic purposes in comparison with foam plastics). Sound attenuation properties of Isover products are characterised by an absorption coefficient α, which can be found in the table for three thicknesses and six frequencies. According to a given noise spectrum, it is possible to design a sound attenuation structure of which our material is only a part. Since we provide only insulation material, we launch only absorption coefficients. Final attenuation will be dependent on the whole designed construction (considering also supporting construction, hangers) and assembly. Isover does not design sound attenuation and thus it is necessary to ask specialists who are able to design a proper structure. Generally we can say that transmission loss is higher for constructions with higher plane weight, therefore in most cases insulation with higher density has better sound attenuation (e.g. slabs Orstech 65, 90, 110, Isover FireProtect 150) than insulation with lower density (e.g. Orstech 45). Slabs can be manufactured with a facing glass black tissue. The practical sound absorption coefficient α p according to EN ISO 354 and EN ISO Frequency (HZ) Orstech 45 Orstech 65 Orstech 90 Orstech 110 Orstech DP 65 Orstech DP 80 Orstech DP 100 Orstech LSP H Isover FireProtect ,15 0,40 0,85 0,95 0,95 0, ,20 0,75 1,00 1,00 1,00 1, ,30 1,00 1,00 1,00 1,00 1, ,45 1,00 1,00 1,00 1,00 1, ,10 0,45 0,90 1,00 1,00 0, ,25 0,80 1,00 1,00 1,00 1, ,35 1,00 1,00 1,00 1,00 1, ,50 1,00 1,00 1,00 1,00 1, ,10 0,55 0,95 1,00 0,95 0, ,25 0,90 1,00 1,00 1,00 1, ,35 1,00 1,00 1,00 1,00 1, ,55 1,00 1,00 1,00 1,00 1, ,15 0,55 0,90 0,95 0,95 0, ,25 0,85 0,95 0,95 0,95 0, ,40 0,90 1,00 0,95 0,95 0, ,55 0,85 0,95 0,95 1,00 1, ,15 0,50 0,95 0,95 0,95 1, ,30 0,85 1,00 1,00 1,00 1, ,40,00 1,00 1,00 1,00 1, ,50 1,00 1,00 1,00 1,00 1, ,15 0,60 1,00 1,00 0,95 1, ,35 1,00 1,00 1,00 1,00 1, ,50 1,00 1,00 1,00 1,00 1, ,60 1,00 1,00 1,00 1,00 1, ,15 0,65 1,00 1,00 0,95 0, ,35 0,95 1,00 1,00 0,95 0, ,45 1,00 1,00 1,00 1,00 1, ,60 1,00 1,00 1,00 1,00 1, ,05 0,15 0,45 0,75 0,90 0, ,15 0,50 0,90 0,95 0,95 1, ,30 0,85 1,00 1,00 1,00 1, ,40 1,00 1,00 1,00 1,00 1, ,05 0,20 0,55 0,85 0,95 1, ,20 0,65 0,90 0,90 0,95 0, ,35 0,85 0,90 0,95 0,95 1, ,45 0,70 0,85 0,95 0,95 1,00 Definition of single number value according to EN ISO α w α stř NCR 0,70 (MH) 0,79 0,80 1,00 0,93 0,95 1,00 1,02 1,00 1,00 1,04 1,05 0,75 (MH) 0,84 0,85 1,00 0,96 0,95 1,00 1,01 1,00 1,00 1,03 1,05 0,85 0,87 0,85 1,00 0,97 0,95 1,00 1,01 1,00 1,00 1,02 1,00 0,85 0,83 0,85 0,95 0,93 0,90 1,00 0,95 0,95 1,00 0,94 0,95 0,80 (H) 0,85 0,85 1,00 0,98 1,00 1,00 1,04 1,05 1,00 1,05 1,05 0,90 0,89 0,90 1,00 1,01 1,00 1,00 1,03 1,05 1,00 1,05 1,05 0,95 0,91 0,90 1,00 0,99 1,00 1,00 1,02 1,00 1,00 1,03 1,05 0,45 (MH) 0,55 0,55 0,80 (H) 0,84 0,85 1,00 0,99 1,00 1,00 1,05 1,05 0,50 (M, H) 0,64 0,65 0,90 0,85 0,85 0,95 0,90 0,90 0,90 0,86 0,

14 General rules for using Isover insulations Between insulated piping sufficient distances must be kept. Valves should be placed without needing to go on the insulated pipes when handling them. Spindle of valves should not be installed in an upward direction to avoid water leakage into the insulation. Surfaces before insulating must be clean and dry. It is not possible to insulate wet or frostbitten surfaces which may later cause damages of insulation or insulated surfaces. Dirt and rust must be rubbed down from untreated carbon steels. Smear and oils must be removed by detergents or solvents from insulated surfaces. Stainless steel surfaces must not be cleaned by detergents or solvents with chloride content. They may be cleaned only by stainless steel brushes. Chloride solution attacks stainless steel surface and causes stress corrosion cracking in the material. With increasing surface temperature the danger of stress corrosion cracking is raised. Piping and equipment from stainless steel can be insulated only by mineral wool insulation in AS quality. Such material can have maximum content of chloride ions of 10 mg in 1 kg of the insulation material. It is necessary to avoid contact of metals which can cause galvanic corrosion (Cu-Zn, Fe-Al). For operating temperatures higher than 600 C aluminium jacketing should not be used. Self-tapping screw, bold or rivet should be from the same material as the jacketing. Surfaces with temperatures higher than 500 C should be insulated by more insulation layers in a way that each layer has a different apparent density. Material with higher density insulates better under higher temperatures than material with lower density; therefore insulation with higher density is placed closer to the hot side. Under low operating temperatures thermal performance is almost equal. Safety working principles must be kept for insulation assembly. Isover products are packed into PE foil. They must be transported in covered vehicles under such conditions to avoid moistening or other degradation. They must be stored in covered places.

15 application of technical insulation PIPING INSULATION For domestic hot water piping with smaller diameters, insulation pipe sections, which are covered with aluminium foil, are ideal. Pipe sections with a facing have a self-adhesive overlap in a longitudinal joint to ensure perfect enclosure of a pipe section. It is recommended to secure pipe sections by an aluminium tape or by galvanized wire transversely. They are usually knotted three times per meter, more for pipe sections with higher diameter. Higher diameters should be secured either by wire or by metal band (at least two bands per meter). Pipings with bigger diameters are most commonly insulated by lamella mats Orstech LSP (stone wool insulation) or Isover ML-3 (glass wool insulation), eventually by wired mats Orstech DP (especially for higher temperatures). Lamella and wired mats are also suitable for appliances and vessels (both ends and cylindrical parts), residential heating systems and air ducts. Wired mats After the cutting of needed length the wired mat shall be tightly wrapped on the pipe. Wired mats butt joints should be in close contact to each other to ensure no gaps between mats. For multiple layer construction each layer is staggered when applied. Each layer must be secured in place before the next is applied. Individual mats are bound together with a wire with minimal 0.7 mm thickness. Alternatively wired hook or stainless steel bands (with minimum width of 10 mm) can be used. Maximum distance between hooks is 150 mm. The decision to use multiple layers may be made for one or more of the following reasons: to provide compensation for pipe expansion and contraction, to reduce heat flow by staggering joints, thus creating a more thermally efficient installation, to achieve thickness in excess of manufacturers capabilities, for retrofitting purposes pipe 2 Isover insulation 3 metal steel jacketing is required for outdoor application Lamella mat Orstech LSP H on bigger diameter piping. Lamella mats Lamella mats Orstech LSP H consist of mineral wool lamellas which have been glued to aluminium foil reinforced with a glass fibre grid, and these fibres are predominantly perpendicular to the surface of the mat. Compressive strength, but thermal conductivity too, are increased compared to mats with a fibre orientation parallel to the surface (wired mats). Due to its compressive strength resistance they have less demands for undeconstruction (less thermal bridges) in comparison with wired mats. Temporary securing in place is done by aluminium tapes, final fixing shall be done by a baling wire. Insulation pipe section before installation. Protective layer removal from the aluminium selfadhesive overlap. Protective coverings The efficiency and service of insulation is directly dependent upon its protection from moisture entry and mechanical and chemical damage. Choices of jacketing materials are based upon the mechanical, chemical, thermal and moisture conditions of the installation, as well as cost and appearance requirements. The basic function of the weather protection is to protect the insulation from rain, snow, sleet, wind, solar radiation, atmospheric contamination and mechanical damage. With this definition in mind, several service requirements must be considered. Butt joints sealing with the aluminium tape. es of metal jacketing materials Perimeter [mm] Galvanized steel [mm] Stainless steel [mm] Aluminium [mm] < >

16 Internal mechanical forces expansion and contraction of the pipe or vessel must be considered because the resulting forces are transferred to the external surface of the weather barrier. Ability to slide, elongate or contract must be provided. External mechanical forces mechanical abuse (i.e., tools being dropped, abrasion from wind-driven sand, personnel walking on the system) inflicted on a pipe or vessel needs to be considered in design. This may affect insulation type, as well as the weather barrier jacketing type. Chemical resistance: Some industrial environments may have airborne or spilled corrosive agents that accumulate on the weather barrier and chemically attack the pipe or vessel jacketing. Elements that create corrosive issues must be well understood and accounted for. Insulation design of coastal facilities should account for chloride attack. Galvanic corrosion: Contacts between two different types of metal must be considered for galvanic corrosion potential. Similarly, water can act as an electrolyte and Fittings, valves Insulation of fittings, valves, flanges and couplings is the most time consuming and often expensive aspect of commercial and industrial insulation. But it is crucial to insulate also these parts properly, otherwise most of energy will be transported by these thermal bridges. For example, for 200 C medium, heat loss of one uninsulated valve corresponds to one meter of uninsulated pipe or ten meters of uninsulated pipe. Fittings are items used to change size, direction of flow, level or assembly of piping. They may be of the screwed, sweat or welded types. Valves are any of various devices that regulate liquid or gas flow and they may be of the screwed, sweated, flanged, or welded types. Flanges are protruding rims and edges of the screwed or sweated type used with fittings, valves, couplings, etc. And finally mechanical couplings are devices used in assembly of Using insulation pipe sections Outside pipe diameter (a) Minimum distances od Pipe (c) Ceilings and walls (b) Using mats Minimum distances Outside pipe diameter (a) od Pipe (c) Ceilings and walls (b) piping. Screwed and flanged connections on fittings, valves, couplings, etc. usually require oversized insulation applications to compensate for the protrusions. Minimum spacing between pipes and constructions galvanic corrosion can occur because of the different potential of the pipe and vessel and a metal jacketing. Materials used as weather barriers for insulation: Typical metal jacketing materials: bare aluminium, coated aluminium, stainless steel, painted steel, galvanized steel, aluminium-zinc coated steel. Typical polymeric jacketing materials: polyvinyl chloride (PVC), polyvinyliedene chloride (PVDC), polyisobutylene, multiple-layer composite materials (e.g., polymeric/foil/ mesh laminates), fabrics (silicone-impregnated fibreglass). It is essential to ensure sufficient space between pipies and between a pipe and a wall (minimally 100 mm). Otherwise, there is a great danger of creating a zone with almost no cenvenction. The result can be too high surface temperature (needed personal protection against burn) or possibility of condensation on cold piping. Besides mounting would have been more difficult. Minimum spacing between pipes and constructions

17 Ducting insulation Isover products are designed to provide high levels of thermal, acoustic and fire protection insulation in HVAC ductwork applications, such as rectangular, flat oval and circular ductwork. The most suitable insulation materials for ducts are felts KLIMAROL with aluminium foil facing, lamella mats Orstech LSP or Isover ML-3, wired mats Orstech DP or slabs Orstech H with aluminium foil facing. Duct insulation mounting Insulation is mostly fixed to the duct by welded pins. When using Orstech H slabs with aluminium facing all the joints shall be sealed with aluminium tape. If a steel clamping band is used it is necessary to use thin-walled steel L-profiles to avoid trimming of the insulation. If using Orstech slabs without aluminium facing or Orstech DP wired mats, proper jacketing shall be made (the most suitable is metal steel jacketing). Lamela mat length calculation for ducting Circular duct: L = (d + 2t) π Rectangular duct: L = 2a + 2b + 8t Cutting of Orstech slabs. d t a t t t b t d t a t t Fixing Orstech slabs to the duct. t b t Sealing joints and edges

18 FIRE PROTECTION OF VENTILATION DUCT Description It is vital to develop safe, durable and reliable solutions for ventilation systems as fire can easily spread from the point of origin via ductwork. Isover meets the highest standards for fire protection, providing excellent fire resistance and top-rated reaction to fire performance. Rectangular ducts shall be insulated by Orstech 65 H slabs with 40 mm thickness (60 mm for fire resistance EI 60 for a horizontal duct); circular ducts shall be insulated by Orstech LSP PYRO lamella mats with 50 mm thickness. By these solutions fire resistances EI 15, 30, 45 and 60 S have been certified to comply with EN Orstech system with fire resistance has been proven to meet the requirements of all possible scenarios for fire from the outside. The scenarios can be identified by duct orientation and duct shape (see table below). Horizontal ducts normally serve one floor of a building. Vertical ducts normally serve between floors of a building. All scenarios have been done only with one layer. Insulation is fixed to a duct by welded pins. Such solution is time and material saving. Fire resistance Horizontal Vertical Rectangular duct EI 15, 30, 45 S 40 mm 40 mm EI 60 S 60 mm 40 mm Circular duct EI 15, 30, 45, 60 S 50 mm 50 mm Metal ductwork The steel duct is constructed in sections of galvanised steel sheet or stainless steel sheet minimum 0.8 mm thick (standard duct sheeting for rectangular ducts specified in DIN 24190, for circular ducts in DIN 24145). Maximum duct size for which classification protocol is valid is 1250 mm (width) x 1000 mm (height) for rectangular duct or diameter up to 1000 mm for a circular duct. Drop rods and hangers Rectangular ducts are suspended by threaded rods and channel section bearers. A duct shall be hung with a suspension system which is independently fire rated according to EN Certificated suspension system MUPRO is recommended for the purpose. Each steel hanger consists of two threaded drop rods, minimum M10 and a channel section bearer 38/40 mm. Fasten the bearer to the drop rods using hexagonal nuts and washers. The drop rods can be positioned either inside the insulation material or outside. If drop rods are outside there is no need to insulate them separately. The bearers are positioned inside the insulation material. Circular ducts are suspended by MÜPRO steel hangers which consist of two threaded drop rods, minimum M10, and a two-part industrial circular band. The ends of each band section are bent outwards. Fasten the band sections together and attach them to the drop rods with hexagonal nuts and washers. Place these hangers inside the insulation. The rods do not need to be protected by insulation. When fixing them to a concrete construction use allsteel expanding anchors to fasten the threaded rod hangers to concrete soffits. The anchors should penetrate the concrete by at least 60 mm. When fixing to a steel supporting construction drill a hole through the steel member, allowing the drop rod to be supported by a steel nut and washer above. If a clamp type fixing is used, the clamp must be steel, suitable for the purpose. It should pass around the steel member and be fastened back on itself. Clamps that rely on friction to hold them in place are not suitable. Detail of the channel section bearer. Flanges with ceramic tape gasket and fire-stopping mastic secured by clamps. At each cross joint flanges are fastened to the duct with spot welds at 150 mm nominal centres. Use a ceramic tape gasket and fire-stopping mastic between the flanges to seal the joints. Flanges are bolted together with an M10 steel nut and bolt at each corner. Fasten the flanges together with steel clamps with bolts M8 (see the figure) in quantity of 3 clamps per 1 meter of the flange length.

19 Insulation Rectangular ducts are insulated by Orstech 65 H slabs (with apparent density 65 kg/m 3 and with one-sided aluminium foil facing) with 40 mm thickness (60 mm for fire resistance EI 60 for a horizontal duct). Circular ducts are insulated by lamella mats Orstech LSP PYRO with 50 mm thickness. Insulation slabs (lamella mats) need to be cut to fit the duct as tightly as possible; the insulation may need to be cut to fit around flanged duct joints. Install the insulation so that one slab (lamella mat) is adjacent and tightly fitted against the other. No gaps must be present between butt joints of insulation. Insulation can be easily cut with a standard laggers knife. There is no need for adhesive on joints. All the joints shall be sealed by aluminium tape. For rectangular ducts in the position of flange the slabs are snick first 15 mm of the thickness to avoid lifting of the slabs. Butt joints should be positioned out of flanges. Fire protective insulation for circular ducts does not require usage of a wire net mesh on the outer side of insulation. Stud welded pins The insulation is fixed to the duct using steel pins, 2.7 mm to 3 mm nominal diameter, and spring steel washers, minimum 30 mm diameter. The length of pin should be equal to the insulation thickness. The orientational number of pins is 16 pieces/m 2 for rectangular ducts and 14 pieces/m 2 for circular ducts. compression in order to completely fill the opening. This must be done, because system ORSTECH Protect does not require stiffeners inside the duct. Then install the second insulation layer so that it is adjacent and tightly fitted against the penetration. The insulation must be cut leaving excess length, so that it exerts some pressure between the penetration and the last fitted piece of insulation. The second layer is fixed by welded pins with length equal to double insulation thickness. The second layer for circular ducts (lamella mats) is clamped with 1-2 wires with a diameter 1.6 mm. Then the insulation is secured to the duct by welded pins. A inovative solution is the considerable simplification of a fire-stopping concept. There is no need to use any kind of stiffener either inside or outside of the duct. A great advantage is to mount the whole ventilation section at once and the wall itself can be placed anywhere. Therefore the position variability of fire separation is provided. No glue or mastic is needed at wall/floor penetrations. Fire classification ORSTECH Protect insulation with fire resistance has been tested by the fire testing laboratory Pavus, a.s., an authorised body AO 216. Classification protocols on the request. Butt joints of insulation are placed apart from flanges. Recommended distance from duct edges and joints is 80 mm, 50 mm from flanges. Wall/floor penetration At wall/floor penetration one must insure the same fire resistance of ventilation duct as has the fire separation to avoid the spreading of fire from one compartment to other via a duct. This is possible by two basic principles or their combinations - install a fire damper at the penetration point or use insulation with fire resistance, where the crucial thing is the fire-stopping. The firestopping is from the second insulation layer with the width of 150 mm from both side of fire separation. The same general principle is used for both rectangular and circular ducts regardless of orientation. Place the duct in the penetration of the construction, with approximately 10 mm gap between insulated duct and opening. Before installing the fire-stopping with the same insulation thickness as is used for the first layer, pack the space between the duct and partition with as many pieces of insulation as possible. Ensure tight Fire protection system ORSTECH Protect has been tested in accordance with EN Maximum size for the rectangular duct is 1250 x 1000 mm and for the circular duct up to diameter 1000 mm. If a duct has bigger dimensions, the certificate connected to the standard cannot be used. More information For more information about fire protective systems ORSTECH Protect and ULTIMATE Protect see product date sheets. Cross-section through a duct at the fire-stopping (wall/floor penetration) There is no need to use any kind of stiffener either inside or outside of the duct

20 Technological appliance insulation Where big quantities of energy is used, e.g. within petrochemical, paper and pulp industries, thermal insulation is necessary in order to reduce expensive energy losses. Tanks, vessels, exhausts, exchangers and technological piping are appliances that are often working at high temperatures. Good insulation will save energy considerably, which will benefit the environment and keep the working costs down. At the same time the insulation will reduce temperature fall, which could disturb the production process. to provide compensation for pipe expansion and contraction, to reduce heat flow by staggering joints, thus creating a more thermally efficient installation, to achieve thickness in excess of manufacturers capabilities, for retrofitting purposes. Insulation is usually fixed by mechanical fasteners - by studs or pins. Spacing between them is dependent on the design of the vessel, its surface temperature, fire hazard potential involved and presumptive loading. Each slab should be fixed by minimally two pins. Boiler insulation Insulations for boilers, kettles and ovens are one of the most demanding applications in industry, because these units are operating at very high temperatures. Good insulation not only saves energy considerably, but the main purpose is personal protection against burn. According to the surface shape and temperature are used either slabs with higher densities Orstech 65 to 110 (for boilers with flat surfaces) or wired mats Orstech DP 65 to DP 100 (for boilers with cylindrical parts). Proper insulation can be chosen in accordance with dimension, surface temperature, the manner of fixing and requirements for jacketing. For pipes and cylindrical parts are used lamella mats Orstech LSP H and Isover ML-3 (only for temperatures up to 250 C) or wired mats Orstech DP. For appliances and vessels with rectangular shapes Orstech slabs are suitable (type according to a surface temperature). Slabs can have aluminium facing. If insulation is done in more than one layer, each layer is staggered when applied. Each layer must be secured in place before the next is applied. The decision to use multiple layers may be made for one or more of the following reasons: Boiler walls are exposed to very high temperatures (usually around 500 or 600 C). Therefore it is essential to use mechanical fasteners for the fixing of insulation to the surface. Insulation for boilers is done in at least two layers; each layer must be staggered when applied. Each layer must be secured in place before the next is applied. A product with high density should be placed as the first layer, because it has a higher maximum surface temperature (higher resistance against high operating temperatures) and better insulation performace than products with lower densities. Chimney insulation Insulations for prefabricated chimneys are directly supplied by producers of such systems. In cooperation with specialized wholesale companies we offer slabs with multi-plate stripes, which allow easy and perfect application for prefabricated chimneys, suitable both for stainless steel chimney liners, as well as with other brands of chimney lining systems. The main advantage is the time saving during the installation in comparison with the use of lamella mats, and horizontal orientation of fibres (better thermal conductivity). Insulation dimensions, i.e. thickness of slabs and groove dimensions dependent on the chimney diameter, are supplied according to customer needs. For non-prefabricated chimneys are mostly used wired mats Orstech DP or slabs Orstech 90 or 110 (for chimneys with rectangular cross-section).