Industry News

Castings Glossary

Alloy — A substance containing two or more chemical elements, at least one of which is metal. The substance usually has metallic properties and possesses qualities different from those of the individual components.

AOD — A refining treatment used to control the carbon content of steel.

Binders — Binders are added to mold materials in order to create a mold of sufficient hardness. Binders can be either organic or inorganic materials.

CAD — Computer Aided Design.

CAM — Computer Aided Manufacturing.

Captive Foundry — A foundry operation that is wholly incorporated into a larger manufacturing operation. A captive foundry only produces castings for the operation that it is a part of.

Casting — A process used to form solid metal shapes out of molten metal. The molten metal is poured into a cavity or a mold.

Charge — Metal and alloy materials that make up the composition of a melt.

Cope — The top half of a horizontally parted mold.

Core — The part of a mold used in the casting process that forms the internal shapes of a casting.

Crucible Furnace — A furnace that melts metals in a refractory crucible. The furnace is typically fueled with coke, oil, gas or electricity.

Cupola Furnace — The traditional furnace used for melting metal. The furnace is typically fueled with coke.

Direct-Arc Furnace — An electric arc furnace in which the metal being melted is one of the poles.

Draft — Taper on the vertical sides of a pattern or corebox that permits the core or pattern to be removed without distorting or tearing of the sand.

Drag — The bottom half of a horizontally parted mold.

Ferrous Metal — An alloy that has iron as the predominant metal.

Flash — A thin section of metal formed at the mold, core, die joint or parting in a casting. Flash usually forms when the cope and drag do not match completely or when the core and the coreprint do not match.

Gas Porosity — A condition in a casting that occurs when gas is trapped in molten metal or as a result of mold gasses that evolved when the casting was poured.

Gating Systems — The channel(s) that allow the molten metal to enter the mold cavity.

Green Sand — Moist sand that is bonded by a mixture that contains silica, bentonite clay, carbonaceous material, and water.

Gross Weight of Casting — The weight of the casting which includes the actual product plus the metal in the gating system as poured.

Hot Isostatic Pressing (HIP) — The process of using high hydrostatic pressure and high temperature to compress fine particles into coherent parts.

Impurity — An element that is allowed into a metal or alloy. Impurities slightly change the properties of the material in some circumstances and can completely damage it in others.

Inclusion — Nonmetallic materials that become part of a metal matrix usually through reoxidation, refractories, slag, and deoxidization products.

Indirect-Arc Furnace — An alternating current electric-arc furnace. The metal being melted is not one of the poles.

Induction Furnace — An alternating current melting furnace that uses the heat of electrical induction.

Investment Casting — A casting process that uses a wax or thermoplastic pattern and is surrounded in a refractory slurry to form a mold. Once the refractory slurry is dry, the wax or plastic is melted out and the mold is formed. Molten metal is then poured in to fill the area that was previously filled with wax.

Jobbing Foundry — A foundry that creates a wide variety of castings, in small quantities for a range of customers.

Ladle — The name for a variety of receptacles used to move and pour molten metal during the casting process.

Lining — The refractory layer of firebrick, clay, sand or other materials that coat the inside of a furnace or ladle.

Lost Foam Process — A casting process that uses foam to form the pattern. The foam is eventually melted out of the mold when the molten metal is poured in.

Metal Yield — The difference between the weight of a finished casting and the total weight of the metal poured.

Mold — The cavity that the molten metal is poured in to form the final shape. A mold usually consists of a top and bottom piece made of sand or ceramic material.

Net Weight of Casting — The final weight of a casting that is determined once all of the excess metal from the gating system has been removed.

Non-ferrous Metal — An alloy that doesn’t have iron as the predominant metal.

Oxidation Losses — The loss of metal or alloy through the process of oxidation.

Oxidizing Atmosphere — Furnace atmosphere which gives off oxygen under certain conditions or where there is an excess of oxygen in the product of combustion, or the products of combustion are oxidizing to the metal being heated.

Pattern — The wood, metal, foam or plastic replica of the final product to be made. Patterns usually include gating systems.

Pattern Draft — The taper allowed on the vertical faces of a pattern to enable removal of the mold or die.

Pigging — Pouring molten metal back into lined containers so that it can be returned to the furnace.

Rapid Prototyping — The computerized equipment that builds a three-dimensional model of a casting from a CAD drawing.

Reducing atmosphere — Furnace atmosphere which absorbs oxygen under suitable conditions or in which there is insufficient air to completely burn the fuel, or the product of combustion is reducing to the metal being heated.

Sand Casting — Producing metal castings out of sand molds.

Sand Reclamation — Processing used sand grains into usable forms so that they can be used in the casting process as a replacement for new sand.

Scrap — All non-product metal produced during the casting process.

Shell Molding — Bringing a resin-bonded sand mixture into contact with a pre-heated metal pattern to form a mold.

Shell Process — The process in which clay-free silica sand coated with a thermostatic resin or mixed with resin is placed on a heated metal pattern for a short period of time to form a partially hardened shell. The bulk of the sand mixture inside the resulting shell is removed for further use. The pattern and shell are heated further to harden or polymerize the resin-sand mix, and the shell is removed from the pattern. Frequently, shell cores are made using this process.

Shotblasting — A process for cleaning castings that involves using a metal abrasive that is propelled by centrifugal or air force.

Shrinkage — The reduction in the volume of metal that occurs as it solidifies.

Shrink Hole — A cavity that forms in a metal part when there was not enough source metal fed into the mold during the casting process.

Slag — A film that forms on top of molten metal as a result of impurities. Slag is composed of non-metal elements.

Slag Inclusions — Imperfections of the surface of metal caused by slag (impurities in the molten mix).

Slurry — The watery mixture such as the gypsum mixture for plaster molding, the molding medium used for investment casting, core dips, and mold washes.

Sprue — The opening in the mold where the metal is first poured.

V-process — A molding process, developed in Japan, in which the mold is formed by stretching a sheet of mylar plastic over a heated metal pattern so that it conforms to the shape of the pattern. A box of loose sand is placed over the pattern, and a vacuum is applied to the sand, which then conforms to the shape of the mylar film. Thus supported, the sand-backed film is removed from the pattern and is used as one part of mold. When the metal is poured, the vacuum is released, and the loose sand falls away from the casting.

Vacuum Casting — The process of casting that uses a vacuum to draw molten metal into a mold that is placed into it.

Furnace parts

• Radiant Tubes
• Tube Supports
• Roller Rails
• Rollers
• Furnace Rolls
• Trays & Grids
• Collector Ducts
• Manifolds
• Retorts
• Muffles
• Pickle Hooks
• Baskets
• Boxes
• Lifting Post Assys.
• Chain Guides
• Generator Tubes
• Fans
• Wire Mesh
• Expanded Metal
• Cast Link Belts
• Custom Fixturing
• Rider Castings
• Inner Covers
• Plenums & Diffusers