Glossary for Seals, Gaskets, O-Rings, Orings, Rubber.

Includes the terms and definitions for seals, seal, orings, gasket, gaskets, hydraulic seals, hydraulic seal, metric seals, metric seal, o-rings, o-ring, viton, teflon, silicone, rubber, nitrile, ucup, plastic, metric orings, injection molding, oil seals, packings, parts, molding, machining.

This is perhaps the most comprehensive glossary of seal, gasket, packing and molded rubber parts terms available on the internet.

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Scorch - Premature vulcanization of a rubber compound, generally due to excessive heat history. Also see Mooney Scorch;

Scorching - A term frequently used to denote premature vulcanization of a rubber compound, occurring on a mill or calender, or in an extruder. Same as burning or "setting up".

Scraper Rings - A ring which rides tight against a rod, with a sharp lip to scrape or wipe off excess oil, dirt or dust in a hydraulic or pneumatic cylinder.

Scrapers - Also, called a wiper ring - A ring which rides tight against a rod, with a sharp lip to scrape or wipe off excess oil, dirt or dust in a hydraulic or pneumatic cylinder.

Seal - An elastomeric ring-shaped component used in a constantly moving, dynamic application - either reciprocating or rotating shaft - providing a near positive no leak mode in a hydraulic cylinder, ram, mixer or gear box - as examples. (Note: no sealing device is absolutely 100% positive). Seal rings can be u-shaped, v-shaped, o-shaped, metal inserted, radial lipped, multiple lipped or a simple flat ring. (See: and for other types of seals)

Seal Cages - A special device used to assist a seal ring.

Seal Kits - Any group of seals, o-rings, wiper rings and back-up rings used to repair a specific hydraulic cylinder.

Seal-Master Machine Instant Seal Making Machine - A special CNC controlled machine for making seals instantly (See:

Seats - A stationary ring which is pressed into a housing and acts as the matching face of a mechanical seal.

Shaft Repair Kits - A package of seals which includes all seals needed to repair the rod end of a hydraulic or pneumatic cylinder.

Shaft Seal & Packings - Any seal ring used on the rod of a hydraulic ram.

Shallex - A brand name for vee packings, chevron or parachute packings.

Sheet Materials - Rubber or fiberous material used to make gaskets.

Shims - Flat, thin metal gasket-like parts used as spacers to position machiery or align equipment.

Shore A Hardness - An indentation method of rating the hardness of rubber using a Shore Durometer with the A scale from 0 to 100.

Shrinkage - Contraction of molded rubber upon cooling.

Skin - A relatively dense layer at the surface of a cellular material.

Simulation - The practice of mimick- ing some or all of the behavior of one system with a different, dissimilar system.

Simultaneous Engineering - A way of simultaneously designing products, and the processes for manufacturing those products, through the use of cross functional teams to assure manufacturability and to reduce cycle time.

Single Acting Seals - Rings which are designed to seal only in one axial direction.

Slip O-rings - A type of ring which fits over an o-ring to relieve friction.

Smoke sheets - Plantation natural rubber sheets that, after passing through a mill that puts the conven- tional ribbing design on them, are washed and hung on racks in a smoke house where they undergo a combined smoking and drying process.

Snap-in Wipers - A rod wiper which is made from one homogeneous material, either rubber or polyurethane, which is designed to snap-fit into a matching machined groove.

Solosele - The brand name of a particular single acting u-cup seals.

Spacers - A ring with flat sides to provide specific dimensional spacing between two components.

Special Characteristics - Product and process characteristics designated by the customer including govern- mental regulatory and safety; and/or selected by the supplier through knowledge of the product and process.

Specific gravity - The ratio of the mass of a unit volume of a material to that of the same volume of water at a specified temperature.

Speedi Sleeves - The name of a thin, round tube which slips over a rotating shaft to provide a new, clean sealing surface for a rubber lip oil or grease seal.

Splice - A joint or junction made by lapping or butting edges, straight or on a bias, and held together through vulcanization or mechanical means.

Spring Energized Seals - Any sealing ring that utilizes a metal garter spring or finger spring to assist in energizing the seal when there is not sufficient pressure.

Spring Loaded Seals - See spring energized seals above.

Sprue - (1) The primary feed channel that runs from the outer face of an injection or transfer mold to mold gate in a single cavity mold or to runners in a multiple cavity mold; (2) The piece of material formed or partially cured in the primary feed channel.

Sprue mark - A mark, usually elevated, left on the surface of an injection or transfer molded part, after removal of the sprue.

Squeeze - Cross section diametrical compression of O-ring between bottom surface of the groove and surface of other mating metal part in the gland assembly.

State of cure - The cure condition of a vulcanizate relative to that at which optimum physical properties are obtained.

Stat-O-Seals - See bonded seals.

Stem Packing - A type of homogeneous or multi-braided packing used on the stem of a valve to stop leakage.

Stepseal - A seal ring with a step cut groove to match up against a housing machine to fit.

Stoppers - See plugs.

Stress - Force per unit of original cross sectional area required to stretch a specimen to a stated elongation.

Stress relaxation - The decrease in stress after a given time of constant strain.

Substrate - A material upon the surface of which an adhesive promo- ter is applied for any purpose such as bonding or coating.

Subsystem - A major part of a system which itself has the charac- teristics of a system, usually consisting of several components.

Swelling - The increase in volume or linear dimensions of a specimen immersed in a liquid or exposed to a vapor.

Swelling - The property of raw or unvulcanized rubber absorbing organic liquids such as benzene, gasoline, etc., arid swelling to many times its original volume. in a general sense, it may be any increase in volume of a solid substance caused by the absorption of a liquid.

Switch Seals - Seals used in electrical switching devices to keep moisture out.

System - A combination of several components or pieces of equipment integrated to perform a specific function.

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