Manufacturing Glossary

Abrasion Resistance:
The ability of a rubber compound to withstand mechanical wear.
Material sticking or holding against another material.
A defect or deformity on the surface of a rubber component.
A raised or bubbled blemish on a custom rubber component caused by an air pocket.
A milky discoloration caused by the migration of compounds on the surface of a rubber component after molding or storage.
The tendency of a rubber product to crack, break or snap under pressure; fragility.
Clamping Force:
The amount of pressure placed on a mold to keep it closed during a molding life cycle.
Cold Runner:
A channel in a rubber mold that carries molding material to mold cavities during injection molding processes.
Color Streaks:
A rubber product defect characterized by a variation in color or a streaking pattern in the molded component.
Compression Molding:
The molding process in which rubber compound is placed in a heated cavity, which is compressed and filled.
The process of removing the excess rubber material (or flash) from a molded product.
A molded rubber defect characterized by the forming of several layers of material or the appearance of separate layers on the surface of a component.
A manufacturing tool used to stamp or cut out a rubber material during compression.
A tool used to measure the hardness of rubber products.
The ability of rubber to return to its original state after removing force such as compression.
A polymer with similar elasticity to rubber.
Excess molding material on the surface or joints of rubber products.
The ability of heated rubber, silicone or other polymers to pass through channels and runners into mold cavities.
Flow Marks:
A manufacturing defect caused by improper flow of rubber material indicated by a wavy surface.
A component used to retain liquids or gases or a seal caused by the compression of two machined materials.
The opening of an injection, compression or transfer mold that ensures flow of rubber, silicone or other polymers.
The measurement of resistance to force of a polymer component.
Heat Sealing:
Method of sealing or joining rubber products by applying constant heat and pressure.
Injection Molding:
A manufacturing molding process in which rubber, silicone or other polymer materials are heated and forced through runners into a mold.
Injection Ram:
The screw or pin that places pressure on the heated compound and forces it into a mold cavity.
Liquid crystal polymer.
Liquid injection molding is a manufacturing process that uses LSR in an injection molding machine.
Liquid silicone rubber is the silicone material used in the liquid injection molding process.
The process of cutting, molding, shaping or finishing products by machine.
Material Hopper:
A container used to store raw polymer materials and pour them into a machine for manufacturing processes.
Mold Cavity:
The hollow space of a mold where the rubber or silicone is shaped.
Mold Storage:
The process in which custom molds are organized, maintained and stored. ARP catalogs their custom molds and stores them in a climate controlled room.
A molecule that can go through the process polymerization.
The molding process that provides the ability to shoot two or more materials into a mold.
A torus shaped mechanical gasket used to seal liquids or gases.
Oscillating Seal:
The inner or outer member of this seal circles around the axis of a shaft.
A receptacle for excess rubber compound ensuring the cavity mold is completely filled.
A molding process that allows previously molded parts to be reinserted forming a new layer of polymer material around the first component.
The chemical reaction of oxygen with rubber involving the transfer of electrons, reducing elastomer strength. This can cause rubber components to crack or become brittle.
The ability of a liquid or gas to diffuse through a rubber or other polymer product or component.
A long molecular chain material formed by the combination of multiple individual units.
Pressure Injection:
Pressure placed on the injection ram where the rubber materials are injected into a mold.
Quad Ring:
An elastomeric ring seal or gasket with a four lobed cross-section.
Radial Seal:
Compression applied to the inside and outside of an o-ring gasket.
Injection moldable materials such as silicone, rubber, other polymers.
Rubber Manufacturers Association.
Rubber Natural:
Raw or crude rubber produced from certain plants and vegetables.
A mold’s distribution system that rubber material travels through to the cavities.
Short Shot:
A lack of rubber material caused by either low pressure, cool temperatures, injection speed, etc.
The contraction of rubber material after molding and cooling.
Silicone Molding:
The manufacturing process in which liquid silicone rubber is heated and injected through a series of runners into a mold producing pliable products such as gaskets, seals and membranes.
A passage liquid rubber material passes through on its way into the mold during injection molding.
A string like or fibrous remnant on a rubber component left over from a previous injection shot.
The adhesive material used to coat or bond to the surface of another material.
Thin-Wall Injection Molding:
A specialized version of injection molding focusing on the manufacturing of thin or light rubber components.
Measurement of size or carrying capacity of a shipping vessel; weight measured in tons.
Transfer Molding:
A molding process in which rubber compound is placed in a pot that is part of the mold, heated and squeezed through sprues and runners into the mold cavity.
Refers to a type of mold used in injection molding, more specifically for overmolding. The first shot of rubber material is injected into the mold with space left for a second shot, usually for rubber of a different type or color.
The measurement of resistance to flow under stress.
The absence of material or empty space in a mold where rubber material did not fill.
The irreversible thermal process converting polymers or rubber into a more durable and resistant compound.
A defect that results in a twisted or distorted rubber product usually caused by incorrect temperature.
Weld Line:
A defect that results in a discolored line where two flow fronts converge.