Molding (

American English American English, sometimes called United States English or U.S. English, is the set of varieties of the English language native to the United States. English is the most widely spoken language in the United States and in most circumstances ...

) or moulding ( British and

Commonwealth English The use of the English language in current and former member countries of the Commonwealth of Nations was largely inherited from British colonisation, with some exceptions. English serves as the medium of inter-Commonwealth relations. Many ...

; see spelling differences) is the process of

manufacturing Manufacturing is the creation or production of goods with the help of equipment, labor, machines, tools, and chemical or biological processing or formulation. It is the essence of secondary sector of the economy. The term may refer to a ...

by shaping liquid or pliable raw material using a rigid frame called a mold or matrix. This itself may have been made using a pattern or model of the final object. A mold or mould is a hollowed-out block that is filled with a liquid or pliable material such as

plastic Plastics are a wide range of synthetic or semi-synthetic materials that use polymers as a main ingredient. Their plasticity makes it possible for plastics to be moulded, extruded or pressed into solid objects of various shapes. This adaptab ...

glass Glass is a non-Crystallinity, crystalline, often transparency and translucency, transparent, amorphous solid that has widespread practical, technological, and decorative use in, for example, window panes, tableware, and optics. Glass is most ...

metal A metal (from Greek μέταλλον ''métallon'', "mine, quarry, metal") is a material that, when freshly prepared, polished, or fractured, shows a lustrous appearance, and conducts electricity and heat relatively well. Metals are typi ...

, or

ceramic A ceramic is any of the various hard, brittle, heat-resistant and corrosion-resistant materials made by shaping and then firing an inorganic, nonmetallic material, such as clay, at a high temperature. Common examples are earthenware, porcelai ...

raw material. The liquid hardens or sets inside the mold, adopting its shape. A mold is a counterpart to a cast. The very common bi-valve molding process uses two molds, one for each half of the object. Articulated molds have multiple pieces that come together to form the complete mold, and then disassemble to release the finished casting; they are expensive, but necessary when the casting shape has complex overhangs. Piece-molding uses a number of different molds, each creating a section of a complicated object. This is generally only used for larger and more valuable objects. Blow molding is a manufacturing process for forming and joining hollow plastic or glass parts. A manufacturer who makes molds is called a

moldmaker A moldmaker (mouldmaker in English-speaking countries other than the US) or molder is a skilled tradesperson who fabricates moulds for use in casting metal products. Moldmakers are generally employed in foundries, where molds are used to cast ...

. A release agent is typically used to make removal of the hardened/set substance from the mold more easily effected. Typical uses for molded plastics include molded furniture, molded household goods, molded cases, and structural materials.

Types

There are several types of molding methods. These includes: * Casting, the oldest term, covering a wide range of materials, especially metals * Blow molding * Powder metallurgy plus sintering * Compression molding * Extrusion molding * Injection molding * Laminating ** Reaction injection molding * Matrix molding * Rotational molding (or Rotomolding) * Spin casting * Transfer molding * Thermoforming ** Vacuum forming, a simplified version of thermoforming * FRP moulding ** Hand lay up moulding ** Resin transfer moulding ** Vacuum bag moulding ** Bladder moulding ** Spray up molding ** Reaction injection molding

Gallery

File:Injection molding die side A.JPG, "A" side of die for glass-filled acetal with 2 side pulls File:Injection molding die with insert.JPG, Close up of removable insert in "A" side File:Injection molding die B side.JPG, "B" side of die with side pull

actuator An actuator is a component of a machine that is responsible for moving and controlling a mechanism or system, for example by opening a valve. In simple terms, it is a "mover". An actuator requires a control device (controlled by control signal) a ...

s File:Injection molding die insert.JPG, Insert removed from die

Procedure

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Types

Gallery

See also

Procedure