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Gaskets
image:gaskets.jpg, Some seals and gaskets A gasket is a Seal (mechanical), mechanical seal which fills the space between two or more mating surfaces, generally to prevent leakage from or into the joined objects while under compression (physical), compression. It is a deformable material that is used to create a static seal and maintain that seal under various operating conditions in a mechanical assembly. Gaskets allow for "less-than-perfect" mating surfaces on machine parts where they can fill irregularities. Gaskets are commonly produced by cutting from sheet materials. Given the potential cost and safety implications of faulty or leaking gaskets, it is critical that the correct gasket material is selected to fit the needs of the application. Gaskets for specific applications, such as high pressure steam systems, may contain asbestos. However, due to health hazards associated with asbestos exposure, non-asbestos gasket materials are used when practical. It is usually desirabl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gaskets
image:gaskets.jpg, Some seals and gaskets A gasket is a Seal (mechanical), mechanical seal which fills the space between two or more mating surfaces, generally to prevent leakage from or into the joined objects while under compression (physical), compression. It is a deformable material that is used to create a static seal and maintain that seal under various operating conditions in a mechanical assembly. Gaskets allow for "less-than-perfect" mating surfaces on machine parts where they can fill irregularities. Gaskets are commonly produced by cutting from sheet materials. Given the potential cost and safety implications of faulty or leaking gaskets, it is critical that the correct gasket material is selected to fit the needs of the application. Gaskets for specific applications, such as high pressure steam systems, may contain asbestos. However, due to health hazards associated with asbestos exposure, non-asbestos gasket materials are used when practical. It is usually desirabl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sealant
Sealant is a substance used to block the passage of fluids through openings in materials, a type of mechanical seal. In building construction ''sealant'' is sometimes synonymous with ''caulking'' and also serve the purposes of blocking dust, sound and heat transmission. Sealants may be weak or strong, flexible or rigid, permanent or temporary. Sealants are not adhesives but some have adhesive qualities and are called ''adhesive-sealants'' or ''structural sealants''. History Sealants were first used in prehistory in the broadest sense as mud, grass and reeds to seal dwellings from the weather such as the daub in wattle and daub and thatching. Natural sealants and adhesive-sealants included plant resins such as pine pitch and birch pitch, bitumen, wax, tar, natural gum, clay (mud) mortar, lime mortar, lead, blood and egg. In the 17th century glazing putty was first used to seal window glass made with linseed oil and chalk, later other drying oils were also used to make oil-bas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polytetrafluoroethylene
Polytetrafluoroethylene (PTFE) is a synthetic fluoropolymer of tetrafluoroethylene that has numerous applications. It is one of the best-known and widely applied PFAS. The commonly known brand name of PTFE-based composition is Teflon by Chemours, a spin-off from DuPont, which originally discovered the compound in 1938. Polytetrafluoroethylene is a fluorocarbon solid, as it is a high-molecular-weight polymer consisting wholly of carbon and fluorine. PTFE is hydrophobic: neither water nor water-containing substances wet PTFE, as fluorocarbons exhibit only small London dispersion forces due to the low electric polarizability of fluorine. PTFE has one of the lowest coefficients of friction of any solid. Polytetrafluoroethylene is used as a non-stick coating for pans and other cookware. It is non-reactive, partly because of the strength of carbon–fluorine bonds, so it is often used in containers and pipework for reactive and corrosive chemicals. Where used as a lubricant, PTFE ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxidation
Redox (reduction–oxidation, , ) is a type of chemical reaction in which the oxidation states of substrate change. Oxidation is the loss of electrons or an increase in the oxidation state, while reduction is the gain of electrons or a decrease in the oxidation state. There are two classes of redox reactions: * ''Electron-transfer'' – Only one (usually) electron flows from the reducing agent to the oxidant. This type of redox reaction is often discussed in terms of redox couples and electrode potentials. * ''Atom transfer'' – An atom transfers from one substrate to another. For example, in the rusting of iron, the oxidation state of iron atoms increases as the iron converts to an oxide, and simultaneously the oxidation state of oxygen decreases as it accepts electrons released by the iron. Although oxidation reactions are commonly associated with the formation of oxides, other chemical species can serve the same function. In hydrogenation, C=C (and other) bonds ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flange
A flange is a protruded ridge, lip or rim (wheel), rim, either external or internal, that serves to increase shear strength, strength (as the flange of an iron beam (structure), beam such as an I-beam or a T-beam); for easy attachment/transfer of contact force with another object (as the flange on the end of a pipe (fluid conveyance), pipe, steam cylinder, etc., or on the lens mount of a camera); or for stabilizing and guiding the movements of a machine or its parts (as the inside flange of a railroad car, rail car or tram train wheel, wheel, which keep the wheels from derailment, running off the rail profile, rails). Flanges are often attached using bolts in the pattern of a bolt circle. The term "flange" is also used for a kind of tool used to form flanges. Plumbing or piping A flange can also be a plate or ring to form a rim at the end of a pipe when fastened to the pipe (for example, a closet flange). A blind flange is a plate for covering or closing the end of a pipe. A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemically Inert
In chemistry, the term chemically inert is used to describe a substance that is not chemically reactive. From a thermodynamic perspective, a substance is inert, or nonlabile, if it is thermodynamically unstable (positive standard Gibbs free energy of formation) yet decomposes at a slow, or negligible rate. Most of the noble gases, which appear in the last column of the periodic table, are classified as inert (or unreactive). These elements are stable in their naturally occurring form (gaseous form) and they are called inert gases. Noble gas The noble gases (helium, neon, argon, krypton, xenon and radon) were previously known as 'inert gases' because of their perceived lack of participation in any chemical reactions. The reason for this is that their outermost electron shells (valence shells) are completely filled, so that they have little tendency to gain or lose electrons. They are said to acquire a noble gas configuration, or a full electron configuration. It is now ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Graphite
Graphite () is a crystalline form of the element carbon. It consists of stacked layers of graphene. Graphite occurs naturally and is the most stable form of carbon under standard conditions. Synthetic and natural graphite are consumed on large scale (300 kton/year, in 1989) for uses in pencils, lubricants, and electrodes. Under high pressures and temperatures it converts to diamond. It is a weak conductor of heat and electricity. Types and varieties Natural graphite The principal types of natural graphite, each occurring in different types of ore deposits, are * Crystalline small flakes of graphite (or flake graphite) occurs as isolated, flat, plate-like particles with hexagonal edges if unbroken. When broken the edges can be irregular or angular; * Amorphous graphite: very fine flake graphite is sometimes called amorphous; * Lump graphite (or vein graphite) occurs in fissure veins or fractures and appears as massive platy intergrowths of fibrous or acicular crystalline ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Punch (metalworking)
A punch is a tool used to indent or create a hole through a hard surface. They usually consist of a hard metal rod with a narrow tip at one end and a broad flat "butt" at the other. When used, the narrower end is pointed against a target surface and the broad end is then struck with a hammer or mallet, causing the blunt force of the blow to be transmitted down the rod body and focused more sharply onto a small area. Typically, woodworkers use a ball-peen hammer to strike a punch. Use Punches are used to drive fasteners such as nails and dowels, making a hole, or forming an indentation/impression of the tip on a workpiece. Decorative punches may also be used to create a pattern or even form an image. Pin Metal pins and similar connectors are driven in or out of holes using a pin punch. For removal, first use a starter punch to loosen the pin, then use a pin punch to finish. Center A ''center punch'' is used to mark the center of a point. It is usually used to mark ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hot Compression Test
Hot or the acronym HOT may refer to: Food and drink *Pungency, in food, a spicy or hot quality *Hot, a wine tasting descriptor Places *Hot district, a district of Chiang Mai province, Thailand **Hot subdistrict, a sub-district of Hot District, Thailand ** Tha Kham, Chiang Mai, also known as Hot, a town in Hot District, Chiang Mai province, Thailand *Hot, Albania, a village in the Malësi e Madhe municipality, Shkodër County, Albania Music * H.O.T. pronounced "H. O. T.", (High-Five of Teenagers), a South Korean boy band *Hawaii Opera Theatre, an opera company in Honolulu, Hawaii *Hot (American vocal group), best known for 1977 hit "Angel in Your Arms" 1976–1980 *Hot 97, branding for hip-hop radio station WQHT in New York City Albums * ''Hot'' (Freda Payne album), 1979 * ''Hot'' (Half Japanese album), 1995 * ''Hot'' (Inna album) or the title song (see below), 2009 * ''Hot'' (James Brown album) or the title song (see below), 1976 * ''Hot'' (Mel B album), 2000 * ''Hot'' (Paul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Truism
A truism is a claim that is so obvious or self-evident as to be hardly worth mentioning, except as a reminder or as a rhetorical or literary device, and is the opposite of falsism. In philosophy, a sentence which asserts incomplete truth conditions for a proposition may be regarded as a truism. An example of such a sentence would be "Under appropriate conditions, the sun rises." Without contextual supporta statement of what those appropriate conditions arethe sentence is true but incontestable. Lapalissades, such as "If he were not dead, he would still be alive", are considered to be truisms. See also * Aphorism * Axiom * Cliché * Contradiction * Dictum * Dogma * Figure of speech * Maxim * Moral * Platitude * Synthetic proposition Synthetic things are composed of multiple parts, often with the implication that they are artificial. In particular, 'synthetic' may refer to: Science * Synthetic chemical or compound, produced by the process of chemical synthesis * Synthetic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pound-force Per Square Inch
The pound per square inch or, more accurately, pound-force per square inch (symbol: lbf/in2; abbreviation: psi) is a unit of pressure or of stress based on avoirdupois units. It is the pressure resulting from a force of one pound-force applied to an area of one square inch. In SI units, 1 psi is approximately equal to 6895 Pa. Pounds per square inch absolute (psia) is used to make it clear that the pressure is relative to a vacuum rather than the ambient atmospheric pressure. Since atmospheric pressure at sea level is around , this will be added to any pressure reading made in air at sea level. The converse is pounds per square inch gauge (psig), indicating that the pressure is relative to atmospheric pressure. For example, a bicycle tire pumped up to 65 psig in a local atmospheric pressure at sea level (14.7 psi) will have a pressure of 79.7 psia (14.7 psi + 65 psi). When gauge pressure is referenced to something other than ambient atmospheric pressure, then the u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
