Weatherproofing

Melamines have found utiUty as rotproofing and weatherproofing ceUulosics (57,58), as binders for pigments and for transfer printing of cotton and cotton blends (59), as well as in numerous other appHcations. Guanamines have been suggested for many of the same appHcations as melamines, but the similar chemical stmctures of the two are likely to add to the same problems encountered with melamines. 

Equipment should be supported in such a way that it will not rest in pools of hquid or on damp insulating material. Porous insulation should be weatherproofed or otherwise protected from moisture and spills to avoid contact of the wet material with the equipment. Specifications should be sufficiently comprehensive to ensure that the desired composition or type of material will be used and the right condition of heat treatment and surface finish will be provided. Inspection during fabrication and prior to acceptance is desirable. 

For impulse withstand voltages across the contact gaps of an interrupting device, refer to lEC 60694 and lEC 60298, Wet or dew test is a weatherproof test (Section I4..5.I0) and is meant for outdoor assemblies. 

The units and ancillary equipment must be protected from mechanical damage and the effects of weather to ensure the reliable operation of an impressed current station. This is achieved by installing it in a weatherproof plastic housing (see Fig. 8-2). Sufficient ventilation must be provided to disperse heat. The ventilation holes should be protected with brass gauze to keep out animals. Transformer-rectifier units must be connected to a circuit that is continuously energized, especially if they are in a building where the current is turned off at night, e.g., gas stations that are not open for 24 h. 

Diem, H., Fritsch, R., Lehnert, H., Matthias, G., Schatz, H. and Wittmann, O., German patent DE 3125874. Process for the preparation of cocondensates which form weatherproof adhesive bonds. Assigned to BASF AG, 1981. 

Wall ventilator A wall air outlet or inlet with a weatherproof cover to provide air exchange between inside and outside by natural forces. 

Wetter, n. weather storm (Mining) damp, also air or ventilation, wetterbestdndig, a. weatherproof. Wetter-beatdndigkeit, /. weather resistance, -dynamit, n. (Mining) permissible dynamite, wetterdynamite. wetterecht, a. fast to exposure. 

Wettereintritt, m. (Mining) air inlet, wetterfest, a. resistant to weather, weatherproof. 

Oil-Well Control. A packaged control unit is available to control individual oil-well pumps. It contains, in a weatherproof enclosure, a combination magnetic starter, a... 

Finally, if the boiler house is to be within an industrial complex and there is no adjacent residential development, the building need only be suitable for adequate weatherproofing of the plant and for maintenance. Alternatively, if it is sited adjacent or near to housing or offices then the building structure should take account of this. 

This falls into two basic groupings supply air systems and extract systems. The equipment used for both is similar, comprising, as a minimum, a fan and weatherproof cowl, plus ducting, air-treatment equipment and grilles as required. 

Fixed ventilation has to be weatherproof to some degree. If it were not, then a simple hole in the wall or roof would be sufficient. The normal form of fixed ventilator is the louver panel. At its simplest, this may be a number of slats of wood mounted at 45-60° in a door or wall opening, and at its most sophisticated an aerodynamically designed two- or three-bank chevron of roll-formed or extruded aluminum (Figure 28.6). 

With all louvers, there is a balance between their weatherproofing qualities and their airflow, and it is important to select a louver with the correct balance for each application. No louver can be guaranteed to be 100 per cent waterproof under all conditions, but the best ones approach this standard under normal flow and wind conditions. 

Most ventilators are powered in one direction with spring return. Thus, a pneumatic ventilator might be described as pressure to open or pressure to close. With the pressure to open type the ventilator will fail to the closed position under the influence of the return spring, ensuring the building remains weatherproof. Where ventilators are installed mainly as smoke ventilators it is important that they fail to the open position, so pressure to close ventilators should be used. A fusible link is normally fitted into the controls so that in the event of fire, affected ventilators will open automatically to release smoke and heat. 

Computers may be used for noise analysis when connected to dedicated hardware devices. One machine incorporates a narrow-band analyzer, octave and one-third octaves with all the features of an environmental noise analyzer. These devices cost much less than purchasing all the dedicated instmments separately. They may be obtained in portable form but are rarely weatherproofed for outdoor use. 

Unsaturated polyester resins based on maleic anhydride are widely used in coatings to manufacture boat hulls and truck caps and a variety of other uses where a smooth, weatherproof, hard-surfaced material is desired. Because these resin types are inherently brittle, hberglass is frequently added for reinforcement. Consumphon of unsaturated polyesters in the U.S. is well over a billion pounds per year, with about 50% going into construction and the marine industry. 

The bead and sealant are required to form a weatherproof seal. 

Conveyor belts, food processing equipment, mining screens. .. Protective clothing, weatherproof clothing. .. 

Weatherproof clothing... Shock-proofing casings. .. Toys... 

The major disadvantage of endothermic wrap fireproofing is when used outdoors, the system must be weatherproofed. Stainless steel jacketing or wrapping with a manufacturer s protective tape is necessary to provide the recommended level of protection. 

Insulation—Perforated and solid metal instrument trays should be completely enclosed with 1 in (25 mm) minimum thickness insulating block or board. The insulation should be secured with stainless steel bands and should be weatherproofed with vinyl-coated galvanized steel sheet. The bands and sheet should be in conformance. The metal jacket should be secured with stainless steel, sheet metal screws or bands. 

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