Wires insulation

Wire coating Wire, corded Wire covering Wire, electrical Wire enamel Wire insulation Wire materials Wire-rope machines Wires... 

Fine Powder Resins. Fine powder PTFE resins are extremely sensitive to shear. They must be handled gendy to avoid shear, which prevents processing. However, fine powder is suitable for the manufacture of tubing and wire insulation for which compression molding is not suitable. A paste-extmsion process may be appHed to the fabrication of tubes with diameters from fractions of a millimeter to about a meter, walls from thicknesses of 100—400 )J.m, thin rods with up to 50-mm diameters, and cable sheathing. Calendering unsintered extmded soHd rods produces thread-sealant tape and gaskets. 

TFE-Fluorocarbon Resins Paste Extrusion of Wire Insulations, buUetia, E.I. du Pont de Nemours Co., Inc., Wilmington, Del., 1961. 

Potting. Potting of wire insulated with Tefzel has been accompHshed with the aid of a coating of a coUoidal siHca dispersion. The pots produced with a polysulfide potting compound meeting MIL-S-8516C Class 2 standards exhibit pullout strengths of 111—155 N (25—35 Ibf). 

Manufactured PVDF parts can be cross-linked using high energy radiation to produce high temperature wire insulation, and heat-shrinkable tubing or film. 

Electrical Properties. CeUular polymers have two important electrical appHcations (22). One takes advantage of the combination of inherent toughness and moisture resistance of polymers along with the decreased dielectric constant and dissipation factor of the foamed state to use ceUular polymers as electrical-wire insulation (97). The other combines the low dissipation factor and the rigidity of plastic foams in the constmction of radar domes. Polyurethane foams have been used as high voltage electrical insulation (213). 

The principal chemical markets for acetylene at present are its uses in the preparation of vinyl chloride, vinyl acetate, and 1,4-butanediol. Polymers from these monomers reach the consumer in the form of surface coatings (paints, films, sheets, or textiles), containers, pipe, electrical wire insulation, adhesives, and many other products which total biUions of kg. The acetylene routes to these monomers were once dominant but have been largely displaced by newer processes based on olefinic starting materials. 

The dielectric constant of a compound is increased by small amounts of absorbed water hence wire insulation for communications generally must have a dielectric constant as stable as possible in the presence of water or moisture. 

Power factor, like the dielectric constant, is a property that represents a power loss that takes place when a wire insulation becomes the dielectric of a condenser because of a surrounding sheath or other conducting medium. 

Organofunctional silanes are used to promote polymer-to-filler bonding with clay or siHca fillers. Vinyl silanes are used in peroxide-cured wire insulation to promote stronger bonding with calcined clay fillers. Mercapto silanes are used to treat kaolin clay in sulfur-cured compounds. 

Because of the stringent U.S. requirements on handling lead-based powders, these stabilizers are only found in flexible electrical wire insulation in the United States because no other stabilizers have been developed which have the low conductivity afforded by these materials. 

Other uses for which special compounds have been developed include materials intended for food contact, wire insulation, and pharmaceutical appHcations. 

Eire retardant grade intended for wire insulation. 

Fig. 9. Splicing connector for two wires (insulation piercing), (a) Exploded view (b) cross section after pressing on wires.

To fulfil the above requirements the material inputs for the motor, such as stampings, steel, enamelled copper wire, insulations and varnishes, bearings, enclosure materials and hardware must be subjected to a series of acceptance tests according to norms and standard specifications. For example, enamelled copper wire used... 

Low eapaeitanee winding teehniques also greatly reduees the dieleetrie stress of the wire insulation. This reduees the possibility of a are jumping between two adjaeent windings due to insulation breakdown. 

Copper Diameter (mm) Maximum Overall Diameter — Wire Insulated Current Capability (A)... 

The polymer first became well known during World War II as a substitute for natural rubber for wire insulation and for waterproof sheeting. After the war it... 

Its excellent electrical insulation properties lead to its use in wire insulation, in valve holders, in insulated transformers, in hermetic seals for condensers, in laminates for printed ciruitry and for many other miscellaneous electrical applications. 

At the present time they are used for a variety of electrical and chemically resistant mouldings, for corrosion-resistant linings, for coatings, for flexible printed circuits and for wire insulation. One particular growth area arising from... 

The markets for polyetherimides arise to an extent from stricter regulations concerning flammability and smoke evolution coupled with such features as high strength, toughness and heat resistance. Application areas include car under-the-bonnet uses, microwave equipment, printed circuit boards and aerospace (including carbon-fibre-reinforced laminated materials). The polymer is also of interest in flim, fibre and wire insulation form. 

Mechanical components (gears, cams, bearings), wire insulation pipe fittings... 

Wire insulation, chemical ware, pipe lining, pipe, process equipment lining... 

Polyvinyl Aldehyde 1940 H VG VG VG VG Most molding pro-cesses Used for coatings and magnet wire insulation, interlayer of safety glasses... 

PVDF IS used as a coating for metallic architectural substrates such as roofing, panel siding, and windows, and for wire insulation in the electronics and aircraft industries It is also used to mold pipes... 

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