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Seal (mechanical)
A mechanical seal is a device that helps join systems and mechanisms together by preventing leakage (e.g. in a pumping system), containing pressure, or excluding contamination. The effectiveness of a seal is dependent on adhesion in the case of sealants and compression in the case of gaskets. The seals are installed in pumps in a wide range of industries including chemicals, water supply, paper production, food processing and many other applications. A stationary seal may also be referred to as 'packing'. Seal types: * Induction sealing or cap sealing * Adhesive, sealant * Bodok seal, a specialized gas sealing washer for medical applications *Bonded seal, also known as Dowty seal or Dowty washer. A type of washer with integral gasket, widely used to provide a seal at the entry point of a screw or bolt * Bridgman seal, a piston sealing mechanism that creates a high pressure reservoir from a lower pressure source * Bung * Compression seal fitting * Diaphragm seal * Ferrofluidi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Seal Mechanical Compression
Seal may refer to any of the following: Common uses * Pinniped, a diverse group of semi-aquatic marine mammals, many of which are commonly called seals, particularly: ** Earless seal, or "true seal" ** Fur seal * Seal (emblem), a device to impress an emblem, used as a means of authentication, on paper, wax, clay or another medium (the impression is also called a seal) * Seal (mechanical), a device which helps prevent leakage, contain pressure, or exclude contamination where two systems join Arts, entertainment and media * ''Seal'' (1991 album), by Seal * ''Seal'' (1994 album), sometimes referred to as ''Seal II'', by Seal * ''Seal IV'', a 2003 album by Seal * ''Seal Online'', a 2003 massively multiplayer online role-playing game Law * Seal (contract law), a legal formality for contracts and other instruments * Seal (East Asia), a stamp used in East Asia as a form of a signature * Record sealing Military * ''Fairey Seal'', a 1930s British carrier-borne torpedo bomber aircr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mechanical Packing
A stuffing box or gland package is an assembly which is used to house a gland seal. It is used to prevent leakage of fluid, such as water or steam, between sliding or turning parts of machine elements. Components A stuffing box of a sailing boat will have a stern tube that is slightly bigger than the prop shaft. It will also have packing nut threads or a gland nut. The packing is inside the gland nut and creates the seal. The shaft is wrapped by the packing and put in the gland nut. Through tightening it onto the stern tube, the packing is compressed, creating a seal against the shaft. , WindCheck Magazine, Retrieved April 27, 2016. Creating a proper plunger alignment is critical for correct flow and a long wear life. Stuffing box components are of stainless steel, brass or other application-specific m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Measurement
Measurement is the quantification of attributes of an object or event, which can be used to compare with other objects or events. In other words, measurement is a process of determining how large or small a physical quantity is as compared to a basic reference quantity of the same kind. The scope and application of measurement are dependent on the context and discipline. In natural sciences and engineering, measurements do not apply to nominal properties of objects or events, which is consistent with the guidelines of the ''International vocabulary of metrology'' published by the International Bureau of Weights and Measures. However, in other fields such as statistics as well as the social and behavioural sciences, measurements can have multiple levels, which would include nominal, ordinal, interval and ratio scales. Measurement is a cornerstone of trade, science, technology and quantitative research in many disciplines. Historically, many measurement systems existed f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inflatable Seal
An inflatable seal is a type of rubber seal that inflates and deflates based on the presence of an inflation source. This allows the seal to accommodate a variable sealing gap. When pressure is applied internally to the seal, it inflates to conform to uneven surfaces and provides a reliable barrier from moisture, damp and other contaminants. How It Works An inflatable seal can be moulded into a concave, flat or convoluted configuration. Once an inflatable medium is placed between the seal and the force, the seal expands and rounds out to create a firm barrier between a mounting and striking surface. The inflatable seal is uniquely designed to return to its original state once the source of inflation has been removed. This lets the technician move both the seal and the other object freely. Applications Inflatable seals can be utilized in an array of industries like electrical, environmental and the military to assist in the following applications to: # Squeeze to assist in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrodynamic Seal
{{Unreferenced, date=June 2019, bot=noref (GreenC bot) A hydrodynamic seal is a type of mechanical seal. A hydrodynamic seals uses a dynamic rotor with grooves that act as a pump and create an air film that the opposing sealing surface will ride on. A hydrodynamic seal performs better than hydrostatic seals by providing greater film stiffness, lower leakage and lower lift off speeds. Hydrodynamic seals have a variety of applications in multiple industries. there are a large number of various groove designs that have been proposed and tested. Types of Hydrodynamic Grooves * Spiral Groove * Wave * V Grooves * U Grooves * Double V Grooves Seals (mechanical) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrostatic Seal
A hydrostatic seal is a non-contacting mechanical seal that operates under an equilibrium of forces. Unlike traditional hydrodynamic seals, Hydrostatic seals have two different pressure zones that are used to establish a balanced pressure zone between two seal faces. The two pressure system makes the seal unique because typical mechanical seals have one pressure zone that created causes a buildup of pressure that will eventually cause the seal to malfunction. After pressure has come to an equilibrium at the seal face, an incompressible fluid is then released between the two seal faces. The fluid creates a film around the seal face that acts as a lubricant and as a medium for the substance flowing through the seal. Hydrostatic seals have been used in the aircraft industry; however they have seen very little commercial use because there is minimal research about the seals. Pressure and Operation Once pressure is applied and the seal comes together, a viscous liquid is released bet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hermetic Seal
A hermetic seal is any type of sealing that makes a given object airtight (preventing the passage of air, oxygen, or other gases). The term originally applied to airtight glass containers, but as technology advanced it applied to a larger category of materials, including rubber and plastics. Hermetic seals are essential to the correct and safe functionality of many electronic and healthcare products. Used technically, it is stated in conjunction with a specific test method and conditions of use. Uses Some kinds of packaging must maintain a seal against the flow of gases, for example, packaging for some foods, pharmaceuticals, chemicals and consumer goods. The term can describe the result of some food preservation practices, such as vacuum packing and canning. Packaging materials include glass, aluminum cans, metal foils, and gas impermeable plastics. Some buildings designed with sustainable architecture principles may use airtight technologies to conserve energy. Under some ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hose Coupling
A hose coupling is a connector on the end of a hose to connect (or ''couple'') it with another hose or with a tap or a hose appliance, such as an irrigation sprinkler. It is usually made of steel, brass, stainless steel, aluminium or plastic. Due to the great variety of the designs and the number of countries in which they were created, it is difficult to trace the origin of many. Patents that cover designs similar to those below include: * 1876: HOSE-COUPLING, No.175,232. * Coupling for hose and pipe. US 894900 A * 1915: Coupling. US 1248558 A * 1931: Coupling. US 1947593 A (claw-types) Threaded coupler types Garden hose thread See Garden hose thread. See also Hoselink and Hozelock plastic click-on connectors. GFR NF E 29-579 GFR Ground joint A "boss" ground joint coupling valve hose coupling, primarily used for compressed air or steam. It consists of a stem, wing nut and spud. It seals as a soft copper seat located in the spud is drawn against the stem by tighten ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heat Sealer
A heat sealer is a machine used to seal products, packaging, and other thermoplastic materials using heat. This can be with uniform thermoplastic monolayers or with materials having several layers, at least one being thermoplastic. Heat sealing can join two similar materials together or can join dissimilar materials, one of which has a thermoplastic layer. Heat sealing process Heat sealing is the process of sealing one thermoplastic to another similar thermoplastic using heat and pressure. The direct contact method of heat sealing utilizes a constantly heated die or sealing bar to apply heat to a specific contact area or path to seal or weld the thermoplastics together. Heat sealing is used for many applications, including heat seal connectors, thermally activated adhesives, film media, plastic ports or foil sealing. Applications for the heat sealing process Heat seal connectors are used to join LCDs to PCBs in many consumer electronics, as well as in medical and telecommunica ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glass-ceramic-to-metal Seals
Glass-to-metal seals have been around for many years, with one of the most common uses being lamp bulb seals. A more recent invention is glass-ceramic-to-metal seals. Properties ''Glass-ceramics'' are polycrystalline ceramic materials prepared by the controlled crystallization of suitable glasses, normally silicates. Depending on the starting glass composition and the heat-treatment schedule adopted, glass-ceramics can be prepared with tailored thermal expansion characteristics. This makes them ideal for sealing to a variety of different metals, ranging from low expansion Tungsten, tungsten (W) or Molybdenum, molybdenum (Mo) to high expansion stainless steels and nickel-based superalloys. Glass-ceramic-to-metal seals offer superior properties over their glass equivalents including more refractory behaviour, in addition to their ability to seal successfully to many different metals and alloys. They have been used in electrical feed-through seals for such applications as vacuum inter ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glass-to-metal Seal
Glass-to-metal seals are a very important element of the construction of vacuum tubes, electric discharge tubes, incandescent light bulbs, glass encapsulated semiconductor diodes, reed switches, pressure tight glass windows in metal cases, Vacuum Insulating Glass (Vacuum Glass) and metal or ceramic packages of electronic components. Properly done, such a seal is Hermetic seal, hermetic (vacuum tight, good electrical insulation, special optical properties e.g. UV lamps). To achieve such a seal, two properties must hold: # The molten glass must be capable of wetting the metal, in order to form a tight bond, and # The thermal expansion of the glass and metal must be closely matched so that the seal remains solid as the assembly cools. Thinking for example about a metal wire in a glass bulb sealing, the metal glass contact can break if coefficients of thermal expansion (CTE) are not well aligned. For the case that the CTE of the metal is larger than the CTE of the glass, the sealing s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Piston Ring
A piston ring is a metallic split ring that is attached to the outer diameter of a piston in an internal combustion engine or steam engine. The main functions of piston rings in engines are: # Sealing the combustion chamber so that there is minimal loss of gases to the crank case. # Improving heat transfer from the piston to the cylinder wall. # Maintaining the proper quantity of the oil between the piston and the cylinder wall # Regulating engine oil consumption by scraping oil from the cylinder walls back to the sump. Most piston rings are made from cast iron or steel. Design Piston rings are designed to seal the gap between the piston and the cylinder wall. If this gap were too small, thermal expansion of the piston could mean the piston seizes in the cylinder, causing serious damage to the engine. On the other hand, a large gap would cause insufficient sealing of the piston rings against the cylinder walls, resulting in excessive blow-by (combustion gases entering the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
