A mechanical seal is a device that helps join systems and mechanisms together by preventing leakage (e.g. in a pumping system), containing

pressure Pressure (symbol: ''p'' or ''P'') is the force applied perpendicular to the surface of an object per unit area over which that force is distributed. Gauge pressure (also spelled ''gage'' pressure)The preferred spelling varies by country a ...

, or excluding contamination. The effectiveness of a seal is dependent on adhesion in the case of

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, so ...

s and compression in the case of

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 ...

s. 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 A bonded seal is a type of washer used to provide a seal around a screw or bolt. Originally made by Dowty Group, they are also known as Dowty seals or Dowty washers. Now widely manufactured, they are available in a range of standard sizes and mater ...

, also known as Dowty seal or Dowty washer. A type of

washer Washer most commonly refers to: *Washer (hardware), a thin usually disc-shaped plate with a hole in the middle typically used with a bolt or nut *Washing machine, for cleaning clothes Washer may also refer to: *Dishwasher, a machine for cleani ...

with integral

, 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 * Ferrofluidic seal *

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 ...

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 ...

** Flange gasket ** O-ring ** O-ring boss seal ** Piston ring *

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 I ...

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 b ...

* Heat seal * Hose coupling, various types of hose couplings * Hermetic seal *

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 betw ...

Hydrodynamic seal {{Unreferenced, date=June 2019, bot=noref (GreenC bot) A hydrodynamic seal is a type of mechanical seal A mechanical seal is a device that helps join systems and mechanisms together by preventing leakage (e.g. in a pumping system), containing pr ...

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 ...

Seals that inflate and deflate in three basic directions of operation: the axial direction, the radial-in direction, and the radial-out direction. Each of these inflation directions has their own set of performance parameters for

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 ...

s such as the height of inflation and the center-line bend radius that the seal can negotiate. Inflatable seals can be used for numerous applications with difficult sealing issues. * Labyrinth seal A seal which creates a tortuous path for the liquid to flow through *

Lid (container) A lid, also known as a cover, is part of a container, and serves as the closure or seal, usually one that completely closes the object. Lids can be placed on small containers such as tubs as well as larger lids for open-head pails and drums. ...

* Rotating face mechanical seal * Face seal * Plug * Radial shaft seal * Trap (plumbing) (siphon trap) * Stuffing box (mechanical packing) * Wiper seal * Dry gas seal

References

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See also

References