![]() ![]() ![]() Bunch stranded conductors are twisted together at one time rather than in layers. Concentric stranded conductors are twisted in progressive layers of 6 wires around 1 wire (7 strand), or 12 wires around 6 wires around 1 wire (19 strand) and 18 wires around 12 wires around 6 wires around 1 wire (37 strand). Other strandings are 37 twisted wires 63 twisted wires, and 127 twisted wires. The most common types of stranded conductors are 7 twisted wires (7 strand), or 16 twisted wires (16 strand), or 19 twisted wires (19 strand). Solid wires twisted together or groups of twisted solid wires which are then twisted together. There are other additional types not listed. Oils: describes a variety of greasy fluid substances that are typically viscous liquids at room temperature, less dense than water, insoluble in water but soluble in alcohol and usually flammable the wide range of compositions make generalizations not useful, but they can be grouped groupings would be petroleum/hydrocarbons, fats/oils, and volatile oils petroleum/hydrocarbons are used as fuels, solvents, and lubricants fats/oils are used in soaps, lubricants. ![]() Aromatic hydrocarbons: organic compounds that contain at least one ring of six carbon atoms, each joined to at least two other carbon atoms typical compounds are toluene, xylene, phenol, benzene, and styrene found in enamel paints, paint strippers, some lacquer coatings, in gaseoline, in engine cleaners, in styrenic plastics, phenolic resins, creosol perservatives and some pesticides. Alkalis: hydroxides of an alkali metal (lithium, sodium, potassium, rubidium, cesium, francium, beryllium, magnesium, calcium, strontium, barium, radium) easily soluble in water and form basic solutions, neutralizes acids, forming salts and water typical alkalis are sodium hydroxide, sodium bicarbonate, calcium hydroxide and calcium carbonate. Aliphatic hydrocarbons organic compounds whose carbon atoms are joined in straight or branched chains instead of rings typical compoiuns are mineral spirits, paint thinner, petroleum distillate, and cyclohexane found in oil and alkyd based coatings, pesticides, furniture oils, cleaners and som cosmetics. Alchols: organic compounds with the general formula R-OH, in which R represents an alkyl group and -OH represents one or more hudroxl groups typical compounds are methanol, ethanol, glycols and isopropanol used in antiseptics, cough syrups, medications, cleaners, coating, shellac, dyes, inks, fuel additives, cosmetics, perfumes and as base materials for plasticizers synthetic lubricants. Six basic types of chemicals are: Acid: can be organic or inorganic have a tendency to dissociate in water to partially or completely ionized in solution typical organic acids are citric acid, carbonic acid, hydrogen cyanide, lactic acid and salicylic acid typical inorganic acids are sulfuric acid, phosphoric acid, nitric acid, hydrogen sulfide and hydrocholir acid. Exposure can range from immersion to occasional contact. The ability of the insulation to withstand exposure to and resist damage by chemicals and substances. ![]()
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