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Brazing And Soldering
Brazing is a metal-joining process in which two or more metal items are joined by melting and flowing a filler metal into the joint, with the filler metal having a lower melting point than the adjoining metal. Brazing differs from welding in that it does not involve melting the work pieces. Brazing differs from soldering through the use of a higher temperature and much more closely fitted parts. During the brazing process, the filler metal flows into the gap between close-fitting parts by capillary action. The filler metal is brought slightly above its melting ( liquidus) temperature while protected by a suitable atmosphere, usually a flux. It then flows over the base metal (in a process known as wetting) and is then cooled to join the work pieces together. Brazing joins the same or different metals with considerable strength. Process Brazing has many advantages over other metal-joining techniques, such as welding. Since brazing does not melt the base metal of the joint, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Unskilled Labor
Skill is a measure of the amount of worker's expertise, specialization, wages, and supervisory capacity. Skilled workers are generally more trained, higher paid, and have more responsibilities than unskilled workers. Skilled workers have long had historical import (''see'' division of labour) as masons, carpenters, blacksmiths, bakers, brewers, coopers, printers and other occupations that are economically productive. Skilled workers were often politically active through their craft guilds. Relative demand of skilled labor One of the factors that increases the relative demand for skilled labor is the introduction of computers. In order to operate computers, workers must build up their human capital in order to learn how such a piece of machinery works. Thus, there is an increase in the demand for skilled labor. In addition to the technological change of computers, the introduction of electricity also replaces man power (unskilled labor) which alters the demand for labor skills. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pin Brazing
Pin brazing is a metallurgically safe method of making electrical connections to steel and ductile iron pipelines as well as other metallic structures, which are to be cathodically protected or electrically earthed. The pin brazing technique is based primarily upon Electric-arc silver soldering using a specially designed portable pin brazing unit, a hollow brazing pin containing silver solder and flux. The brazing process is initiated by depressing a trigger on the brazing gun. This, as with most forms of electrical welding, simply completes a circuit through which a DC current is passed. The pin tip is the point of highest resistance at which point an arc is drawn, melting the solder flux whilst simultaneously heating the lug material and the surface of the structure or pipeline to the required soldering temperature. After approximately 1.5 seconds the circuit is mechanically or electronically broken, the solenoid is de-energised and the brazing pin is pushed forward into th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Copper-nickel
Cupronickel or copper–nickel (CuNi) is an alloy of copper with nickel, usually along with small quantities of other metals added for strength, such as iron and manganese. The copper content typically varies from 60 to 90 percent. (Monel is a nickel–copper alloy that contains a minimum of 52 percent nickel.) Despite its high copper content, cupronickel is silver in colour. Cupronickel is highly resistant to corrosion by salt water, and is therefore used for piping, heat exchangers and condensers in seawater systems, as well as for marine hardware. It is sometimes used for the propellers, propeller shafts, and hulls of high-quality boats. Other uses include military equipment and chemical industry, petrochemical industry, and electrical industries. In decorative use, a cupronickel alloy called nickel silver is common, although it contains additional zinc but no silver. Another common 20th-century use of cupronickel was silver-coloured coins. For this use, the typical alloy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thou (length)
A thousandth of an inch is a derived unit of length in a system of units using inches. Equal to of an inch, a thousandth is commonly called a thou (used for both singular and plural) or, particularly in North America, a mil (plural mils). The words are shortened forms of the English and Latin words for "thousand" ( in Latin). In international engineering contexts, confusion can arise because ''mil'' is a formal unit name in North America but ''mil'' or ''mill'' is also a common colloquial clipped form of millimetre. The units are considerably different: a millimetre is approximately 39 mils. Contexts of use The thou, or mil, is most commonly used in engineering and manufacturing in non-metric countries. For example, in specifying: * The thickness of items such as paper, film, foil, wires, paint coatings, latex gloves, plastic sheeting, and fibers ** For example, most plastic ID cards are about in thickness. ** Card stock thickness in the United States, where mils are also ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crack In CuNi Metal Due To Silver Brazing
Crack frequently refers to: * Crack, a fracture in a body * Crack, a fracture (geology) in a rock * Crack, short for crack cocaine Crack(s) or The Crack may also refer to: Arts, entertainment, and media * '' The Crack'', first album by The Ruts * ''Crack'' (album), an album by Z-RO * Crack (band), a Spanish progressive rock group * ''The Crack'' (magazine), a free culture magazine covering the North East of England * ''Crack'' (magazine), a UK-based European music and culture monthly * Crack Movement, a Mexican literary movement * ''Cracks'' (album), an album by Nabiha * ''Cracks'' (film), a 2009 independent thriller Software * Crack (password software), a UNIX/Linux password hacking program for systems administrators * Software cracking, a computer program that modifies other software to remove or disable features usually related to digital rights management * No-disc crack, software to circumvent Compact Disc and DVD copy protection *Password cracking, the process of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cemented Carbide
Cemented carbides are a class of hard materials used extensively for cutting tool material, cutting tools, as well as in other industrial applications. It consists of fine particles of carbide cemented into a composite material, composite by a binder metal. Cemented carbides commonly use tungsten carbide (WC), titanium carbide (TiC), or tantalum carbide (TaC) as the aggregate. Mentions of "carbide" or "tungsten carbide" in industrial contexts usually refer to these cemented composites. Most of the time, carbide cutters will leave a better surface finish on a part and allow for speeds and feeds, faster machining than high-speed steel or other tool steels. Carbide tools can withstand higher temperatures at the cutter-workpiece interface than standard high-speed steel tools (which is a principal reason enabling the faster machining). Carbide is usually superior for the cutting of tough materials such as carbon steel or stainless steel, as well as in situations where other cutting t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Torr
The torr (symbol: Torr) is a Pressure#Units, unit of pressure based on an absolute scale, defined as exactly of a standard atmosphere (unit), atmosphere (101325 Pa). Thus one torr is exactly (≈ ). Historically, one torr was intended to be the same as one "millimetre of mercury", but subsequent redefinitions of the two units of measurement, units made the torr marginally lower (by less than 0.000015%). The torr is not part of the International System of Units (SI). Even so, it is often combined with the metric prefix milli to name one millitorr (mTorr), equal to 0.001 Torr. The unit was named after Evangelista Torricelli, an Italian physicist and mathematician who discovered the principle of the barometer in 1644. Nomenclature and common errors The unit name ''torr'' is written in letter case, lower case, while its symbol ("Torr") is always written with an uppercase initial; including in combinations with prefixes and other unit symbols, as in "mTorr" (millitorr) or " ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pascal (unit)
The pascal (symbol: Pa) is the unit of pressure in the International System of Units (SI). It is also used to quantify internal pressure, stress, Young's modulus, and ultimate tensile strength. The unit, named after Blaise Pascal, is an SI coherent derived unit defined as one newton per square metre (N/m2). It is also equivalent to 10 barye (10 Ba) in the CGS system. Common multiple units of the pascal are the hectopascal (1 hPa = 100 Pa), which is equal to one millibar, and the kilopascal (1 kPa = 1000 Pa), which is equal to one centibar. The unit of measurement called '' standard atmosphere (atm)'' is defined as . Meteorological observations typically report atmospheric pressure in hectopascals per the recommendation of the World Meteorological Organization, thus a standard atmosphere (atm) or typical sea-level air pressure is about 1013 hPa. Reports in the United States typically use inches of mercury or millibars (hectopascals). In Cana ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Refractory
In materials science, a refractory (or refractory material) is a material that is resistant to decomposition by heat or chemical attack and that retains its strength and rigidity at high temperatures. They are inorganic, non-metallic compounds that may be porous or non-porous, and their crystallinity varies widely: they may be crystalline, polycrystalline, amorphous, or composite. They are typically composed of oxides, carbides or nitrides of the following elements: silicon, aluminium, magnesium, calcium, boron, chromium and zirconium. Many refractories are ceramics, but some such as graphite are not, and some ceramics such as clay pottery are not considered refractory. Refractories are distinguished from the '' refractory metals'', which are elemental metals and their alloys that have high melting temperatures. Refractories are defined by ASTM C71 as "non-metallic materials having those chemical and physical properties that make them applicable for structures, o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zirconium
Zirconium is a chemical element; it has Symbol (chemistry), symbol Zr and atomic number 40. First identified in 1789, isolated in impure form in 1824, and manufactured at scale by 1925, pure zirconium is a lustrous transition metal with a greyish-white color that closely resembles hafnium and, to a lesser extent, titanium. It is solid at room temperature, Ductility, ductile, malleable and corrosion-resistant. The name ''zirconium'' is derived from the name of the mineral zircon, the most important source of zirconium. The word is related to Persian Language, Persian ''Jargoon, zargun'' (zircon; ''zar-gun'', "gold-like" or "as gold"). Besides zircon, zirconium occurs in over 140 other minerals, including baddeleyite and eudialyte; most zirconium is produced as a byproduct of minerals mined for titanium and tin. Zirconium forms a variety of inorganic chemistry, inorganic compounds, such as zirconium dioxide, and organometallic compounds, such as zirconocene dichloride. Five isotope ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Titanium
Titanium is a chemical element; it has symbol Ti and atomic number 22. Found in nature only as an oxide, it can be reduced to produce a lustrous transition metal with a silver color, low density, and high strength, resistant to corrosion in sea water, aqua regia, and chlorine. Titanium was discovered in Cornwall, Great Britain, by William Gregor in 1791 and was named by Martin Heinrich Klaproth after the Titans of Greek mythology. The element occurs within a number of minerals, principally rutile and ilmenite, which are widely distributed in the Earth's crust and lithosphere; it is found in almost all living things, as well as bodies of water, rocks, and soils. The metal is extracted from its principal mineral ores by the Kroll and Hunter processes. The most common compound, titanium dioxide (TiO2), is a popular photocatalyst and is used in the manufacture of white pigments. Other compounds include titanium tetrachloride (TiCl4), a component of smoke screens and cata ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
