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INSULATING COATINGS Duomar is the manufacturer of thermal and acoustic insulation coatings and interior mounting systems for various industries based out of Netherlands. The Duocoat® insulating coatings of Duomar can be devided into two major categories : THERMAL : ACOUSTIC : & HOW DOES IT WORK ?? : First of all, What is heat ? Heat may be defined as energy in transit from a high-temperature object to a lowertemperature object. The noun heat is defined only during the process of energy transfer by conduction, convection or radiation. In a thermodynamic sense, heat is never regarded as being stored within a body. Heat only exists as energy in transit from one body to another; in thermodynamic terminology, between a system and its surroundings. When energy in the form of heat is added to a system, it is stored not as heat, but as kinetic and potential energy of the atoms and molecules making up the system. The Flow of Heat Heat transfers in three different ways : Radiation ~ No medium needed Conduction ~ Through a solid Convection ~ Combined effect of conduction and fluid flow (Gas or liquid) Emissivity : The emissivity of a material (usually written ε) is the ratio of energy radiated by a particular material to energy radiated by a black body at the same temperature. It is a measure of a material's ability to absorb and radiate energy. A true black body would have an ε = 1 while any real object would have ε < 1. Emissivity is a dimensionless quantity and does not have units. Emissivity explained easy : Simplified, emissivity is the speed in which the object transfers heat. For instance, when you bake a loaf of bread in the oven, the oven reaches an equilibrium in temperature, meaning that the whole oven is for instance 180°C. When the bread is done, you can take it out of the oven. Although it feels hot, you can touch it. On the other hand, if you try to take the bread out of the oven by grabbing the rack, you will be sure to burn your hands ! Eventhough both products are 180°C !!!! Emissivity Temperature explained easy : This brings us to the unit Temperature. People always tend to measure the insulation properties by the outside temperature. This while temperature is in fact an empty meaningless unit. To explain this easy, compare temperature to voltage. Voltage is also not a unit for energy transfer. A 110/220 or 380 Volt socket can be leathal while a 50.000 Volt Taser only stuns you for a certain period, this because the Taser has a much lower Amperage, so a much lower energy flow. TEMPERATURE WITHOUT EMMISIVITY = VOLTAGE WITHOUT AMPERAGE 110 / 220 VOLT 380 VOLT 50.000 VOLT Concept of Emissivity Duocoat® TI is insulating products that combines all aspects of heat transfer to create its unique insulation capacity. The insulating fillers (85%) in the coating have a highly reflective value based on their chemical composition and geometrical composition. The wall material of the hollow spherical particals is very thin, reducing conduction. Held in suspension by the resin, they also eliminate the convection of heat through the coating. Application thicknesses : The application thickness of Duocoat® TI is depending on several factors like : Substrate material and thickness Goal of the insulation ( PP, Energy retention, CUI prevention, anti condensation etc.) Climate surrounding the application Stand-alone or in combination with additional insulation. In general Duocoat® TI is applied ranging from 1.0 mm DFT to 3 mm DFT. Advantages of Duocoat TI in Railway: •To create a thin insulation layer that improves the climate inside the carriages. •Due to the little space they have inside the carriages, the conventional insulation doesn’t always perform as good as it should do, resulting in a quick raise of temperature inside the carriages. •This will be drastically improved with the use of Duocoat TI, giving great flexibility for Coach design •Create more space for Passengers •Long life - Will last For life of the Coach Advantages of Duocoat® TI compared with conventional insulation are : Thin Layer provides high Insulation. Adheres directly to the surface, eliminating moisture build up under the insulation and thus protecting against Corrosion Under Insulation. (CUI) Enables visual inspection Fast application and Easy application, even on irregular surfaces or complex shapes. Withstands severe weather conditions. Flexible Coating, will not crack or crumble Water based Coating that is environmentally and fire safe No moisture build in the coating, resulting in constant insulation value. Applications & Area’s : Duocoat® VD is used to reduce structural noise and vibration in various industries. Duocoat VD is applied to area’s around the source of structural vibrations such as : Around the engine Machine enclosures Coach Frame Coach Body HVAC ducting Duocoat® VD can even be applied to irregular or curved surfaces. HOW DOES IT WORK ?? : First of all, there are two major forms of sound transmission : Airborne : Sound waves transmitted through air. Mostly higher frequencies. Insulation of these sound waves needs to be done by absorbtion. Structural: Sound waves / vibrations transmitted through a solid / structure. These vibrations will travel through the construction and will be radiated to airborne noise, like a speaker, through flat panels in the construction. Insulation like fibre or foam insulation will not stop these vibrations. HOW DOES IT WORK ?? : Duocoat® VD forms a visco-elastic layer that suppresses vibrations in sheet metal constructions, reducing structural to airborne noise radiation and transmission of structural vibrations. Duocoat® VD gets its functionality from a combination of three aspects : Weight Youngs Modulus (Elasticity) Functional fillers APPLICATION THICKNESS : The application thickness of Duocoat VD is depending on several factors, of which the most important factors are : • Substrate material (Mostly steel or aluminium) • Substrate thickness • Expected frequencies If the customer does not use the services of a sound consultant, we generally advise to apply dry layers of Duocoat® VD in the ratio : 50% of the substrate thickness to aluminium. 75% of the substrate thickness to steel, with a maximum of 8 mm steel. Use of Duocoat VD in Railways • Duocoat VD has been used on the floors and walls of the carriages • Mainly to prevent the noise burden caused by vibrations such as the contact between the carriage and the rails and the wind and weather noises. • The choice for Duocoat VD is based on the quality level of noise damping and the ease of application, as well as the aesthetic end result.