"G"

Gap Seals - A seal ring used to seal between the gaps of metal or plastic.

Gasket - A flat, non-moving, compressible rubber-like device squeezed between two flat sufaces forming a static seal. Gaskets can be made from homogeneous rubber, fabric reinforced rubber, fiberous materials with rubber binders, flexible graphite, PTFE and many other materials. Some gaskets are made from a combination of metal and fiberous materials and some are all metal. An o-ring, while not flat is also referred to as a gasket at times.

Gate - (rubber injection or transfer mold) - The orifice used to control the flow of rubber, and through which a shaped cavity in a mold is filled with rubber.

Gland Bearing Rings - Also called guide rings or wear rings used as a bearing surface for the rod of a hydraulic ram or cylinder.

Gland Seals - Seals or packings used a the main sealing device in a ram or cylinder.

Glandsele - The brandname of a type of rod seal.

Glass Temperature (Tg) - The temperature at which a rubber becomes glass-like. a more recent name for Second Order Transition point.

Glass transition point - Temp- erature at which a material loses its glass-like properties and becomes a semi-liquid.

Globe Valve Discs - Teflon® rings used to seal in a globe valve.

Glyd Ring - Also known as wear rings or guide rings - made from plastic, Teflon® or soft metal to act as a bearing surface for a cylinder rod.

Grain - The unidirectional orientation of rubber or filler particles occurring during pro- cessing (extrusion, milling, calen- dering) resulting in anisotropy of a rubber vulcanizate.

Grease Seals - Also called oil seals, rotary seals or shaft seals. Made of rubber to seal grease in a housing with a rotating shaft.

Green strength - (1) The resistance to deformation of a rubber stock in the uncured state. (2) Uncured adhesion between plied or spliced surfaces.

Grommets - A rubber ring used to fit into a hole in sheet metal aloow wires, shafts or rod to exit the housing without touching the metal.

Guiding Elements - Wear rings, guide rings, guiding rings, bearing rings for hydraulic cylinder rods.

Guide Rings - See also wear rings, guide rings or bearing rings. Usually made from a form of Teflon® or PTFE.