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Seal (mechanical)
A seal is a device or material that helps join systems, mechanisms or other materials together by preventing leak, leakage (e.g. in a wikt:pumping, 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 a 'packing'. Seal types: *Induction sealing or cap sealing *Sealant, Adhesive, sealant *Bodok seal, a specialized gas sealing washer for medical applications *Bonded seal, also known as Dowty Group, Dowty seal or Dowty washer. A type of Washer (hardware), 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 ... [...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, also called "true seal" ** Fur seal ** Eared 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 ** Hermetic seal, an airtight mechanical seal * Security seals such as labels, tapes, bands, or ties affixed onto a container in order to prevent and detect tampering Arts, entertainment and media * Seal (1991 album), ''Seal'' (1991 album), by Seal * Seal (1994 album), ''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 la ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gasket
Some seals and gaskets A gasket is a 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. 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 desirable that the gasket be made from a material that is to some de ... [...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 th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrodynamic Seal
A hydrodynamic seal is a type of mechanical seal. A hydrodynamic seal 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. Some types of hydrodynamic grooves include: * Spiral Groove * Wave * V Grooves * U Grooves * Double V Grooves Seals (mechanical) {{mechanical-engineering-stub ... [...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 be ... [...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 metals, 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. Colloquially, the exact requirements of such a seal varies with the application. Etymology The word ''hermetic'' comes from the Greek god Hermes. A hermetic seal comes from alchemy in the tradition of Hermeticism. The legendary Hermes Trismegistus supposedly invented the process of making a glass tube airtight using a secret seal. Uses Some kinds of packaging must maintain a seal against the flow of gases, for example, packaging for some foods, pharmaceuticals, chemicals, ... [...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 ti ... [...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. 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 Heat seal connectors are used to join LCDs to PCBs in many consumer electronics, as well as in medical and telecommunication devices. Heat sealing of produc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glass-to-metal Seal
Glass-to-metal seals are a type of mechanical seal which joins glass and metal surfaces. They are very important elements in the construction of vacuum tubes, electric discharge tubes, incandescent light bulbs, glass-encapsulated semiconductor diodes, reed switches, glass windows in metal cases, and metal or ceramic packages of electronic components. Properly done, such a seal is Hermetic seal, hermetic (capable of supporting a vacuum, 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 the coefficients of thermal expansion (CTE) are not well aligned. For the case that the CTE of the metal is large ... [...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 th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
O-ring Boss Seal
An o-ring boss seal is a technique for joining two fluid-carrying pipes, hoses, or tubing. In an o-ring boss (abbreviated ORB) system, a male- threaded part is inserted into a female-threaded part, providing a mechanical seal. This system differs from others in that a nut is tightened over an o-ring in a chamfered area, creating a fluid-tight seal. Application This system is used frequently in hydraulics, although it has been applied to other systems including compressed air systems and vacuum pump A vacuum pump is a type of pump device that draws gas particles from a sealed volume in order to leave behind a partial vacuum. The first vacuum pump was invented in 1650 by Otto von Guericke, and was preceded by the suction pump, which dates to ...s, such as many Robinair pumps, in which the intake tee has an o-ring boss seal on the bottom. The ORB system can be confused with other connection systems, such as NPT. While threads of different connectors sometimes fit (although ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
