SOUND INSULATION

Used as a light-weight aggregate in heat and sound insulating plasters, as a loose fill and in... 

Classification for Rating Sound Insulation, ASTM E413-87, ASTM, Philadelphia, Pa., 1987. 

The main characteristic properties of asbestos fibers that can be exploited in industrial appHcations (8) are their thermal, electrical, and sound insulation nonflammabiUty matrix reinforcement (cement, plastic, and resins) adsorption capacity (filtration, Hquid sterilization) wear and friction properties (friction materials) and chemical inertia (except in acids). These properties have led to several main classes of industrial products or appHcations... 

Loose asbestos fibers, or formulations containing asbestos fibers for spray coatings, have been widely used in the building industry for fire protection and heat or sound insulation. Such applications used mainly chrysotile or amosite but, because of health concerns, this practice has been discontinued. 

Thermal Insulation. Foamed plastics (qv) are used as thermal insulation for aU types of constmction because of their low heat- and moisture-transmission values. Polystyrene is used either as foamed board or expandable beads. The foam may be faced with a stmctural surfacing material, eg, a kraft liner-board, to form a panel for insulating mobile homes. These foams can dupHcate the appearance of wood and be used as trim. Foams can also be used as backing, for example, on aluminum siding, to provide heat and sound insulation. Foamed beads can be incorporated in concrete to reduce its density and provide some thermal insulation. 

Amongst applications reported are underfloor footfall sound insulation, thermal insulation between cavity walls and pipe insulation. 

Linnecessary noise, these should be cleaned regularly. Imbalance, whether due to dirt or to other causes, should be corrected by adjustment. Detective bearings should be adjusted or replaced. Struts and sharp edges in front of an impeller should be avoided. Impact noise insulation should be introduced between fan room and floor structure and between fan room and connecting ducts. The fan unit should be enclosed, with satisfactory airborne sound insulation as the objective. 

If insulation panels are not of uniform construction (as in the case of a wall containing a window) the average sound-insulation value must be derived for use in calculations. The total transmission coefficient for the composite panel will equal the sum of the individual coefficient times their respective areas divided by the total area. Thus ... 

The architect continues to look for products that can he multifunctional. As an example in roofing, the product could perform a part or all of the functions. The roof has to provide structural integrity, temperature and sound insulation, vapor and moisture control, weather resistance, elastic qualities for change in weather, fire protection, aesthetic appeal, and so on. 

The ranges of properties in plastics encompasses all types of environmental and load conditions, each with its own individual, yet broad, range of properties (Fig. 1-9). These properties can take into consideration wear resistance, integral color, impact resistance, transparency, energy absorption, ductility, thermal and sound insulation, weight, and so forth. There is unfortunately no one plastic that can meet all maximum properties. Therefore, the designer has different options, such as developing a compromise because many product requirements provide options, particularly if cost is of prime importance. 

An outstanding property of EPS is its extremely low density (when compared to other processes), that by alteration of the preforming treatment can be varied according to the end use. Other types of plastics are employed to produce expandable plastic foam (EPF), including PE, PP, PMMA, and ethylene-styrene copolymers. They can use the same equipment, with only slight modifications. These plastics have different properties from those of EPS and open up different markets. They provide improved sound insulation, resistances to additional heat deformation, better recovery of shapes in moldings, and so on. 

Foamed polymeric materials can have either a closed or open cellular structure. Closed cells tend to be favoured when the pressure is maintained during the expansion. Both types are used for different applications, e.g., closed for thermal and sound insulation, open cell for soaking up liquids by capillary... 

Parmanen, Juhani, Sipari, Pekka Uosukainen, Seppo. Sound insulation of multi-storey houses. Summary of impact sound insulation. 1999. 22 p. 

The Sonotech Cello pulse combustion system has the same limitations as a nonpulsating burner attached to a combustion device. Preliminary testing of the Sonotech system showed that in order to prevent slag formation, the temperature of the rotary kiln gas should not exceed 1700°F. The system produces considerable noise, which may be controlled by sound insulation. The Sonotech system uses resonant frequency of the incinerator to create pulsations. In an older incinerator, if the sound energy is not properly applied, the Sonotech system could cause structural problems. 

PUR Cushioning materials, packaging, padding (e.g., furniture, sound insulation panels, wood imitations, transportation) ... 

Now, Boston-based Cabot Corp. is rolling out the first major commercial application of the silicon-based material window and skylight panels that use aerogels for heat and sound insulation while allowing light to... 

Kanegafuchi Chemical of Japan has introduced a chemical cross-linking process for producing PE foams by the bead technique similar to EPS. Their Eperan heads have been used io produce molded articles as cushioning materials, sound insulating panels, etc. Asahi-Dow and BASF have also been reported to have developed similar producls. 

Uses, Concrete aggregate, heal and sound insulation, filtration, finishing glass and plastics, road construction, scouring preparations, paint fillers, absorbents, support for catalysts, and dental abrasive. 

Finally, oligomers in reactive processing to produce foamed plastics and elastomers for various industrial purposes. These materials have many of the valuable properties of conventional polymers, with the addition of low density and high heat, electrical, and sound insulation characteristics.23... 

Figure 3.2 Cross section of an expanded foam rubber heat- and sound-insulation tube of a poly(aryloxyphosphazene). Reproduced by permission of Ethyl Corporation.

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