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St. Paul Foundry

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Aging- a change in metal structure wherein it recovers from an unstable condition by precipitation and resulting in a change in mechanical properties. Aging may be accelerated by heating, quenching or cold working.

Annealing- a process of heating followed by slow cooling usually to soften, increase ductility and/or stabilize dimensions.

Automatic Molding Machine- a fully automated system that makes molds at a very high rate of speed. Most systems are integrated with sand mulling and mold handling equipment. Modern molding machines compact sand under very high pressure resulting in very accurate reproduction and excellent surface finish.

Back Draft- taper that goes the wrong direction preventing the removal of a pattern from the sand.

Beardsley and Piper (B&P)- a popular brand of molding machine. B&Ps blow sand into the mold from the side. Because of this they can fill the cope and drag simultaneously.

Bottom Board- a flat base used to support the flask or mold during molding and pouring.

Bull Ladle- a ladle used for transferring metal to smaller pouring ladles.

Chaplet- a metallic support used to hold a core in position in a mold.

Charge- verb- to put metal in a furnace for melting. noun- the metal that is placed in a furnace for melting.

Cheek- intermediate sections of a mold used to create multiple parting lines and mold difficult shapes.

Chill- verb- to cool rapidly. noun- an object placed integral with the surface of the mold cavity to cool rapidly specific sections of the casting.

Choke- a constriction in the gating system that causes pressure in all parts of the system upstream from it.

Cleaning- the composite act of shaking out, shot blasting and grinding castings to make them saleable.
Cold Working-mechanically aging metal by bending, hammering, peening, etc..

Cope- the top half of a horizontally parted mold.

Cope and Drag Molding- a molding method where there are two patterns, one for the cope and one for the drag. The halves of the mold are made separately and then assembled away from the molding machine.

Core- a separately made sand shape, usually baked or chemically bonded, inserted in a mold to form the inside of a casting or parts which could not otherwise be shaped by the pattern.

Core Drier- sand or metal supports to keep cores in shape during baking.

Coreless Induction Furnace- an electric melting unit that induces a current in the metal charge. The resistance of the metal to that current creates heat.

Core Print- an extension on the pattern that forms a socket into which cores can be located.

Core Wash- a slurry that is applied to a core surface to improve surface finish, prevent penetration or keep gas from going into the metal.

Crucible- a pot made of a refractory material in which metal is melted and sometimes from which metal is poured.

Cupola- a stack type melting unit in which metal is melted in direct contact with the fuel.

Cutoff- a machine using either abrasives or saw blades to remove rigging from castings.

Disamatic- a proprietary brand of automatic molding machine. Disamatics make vertically parted molds that book together in a continuous series of molds.

Drag- the bottom half of a horizontally parted mold.

Dross- metal oxides on or in a metal alloy.

Electric Radiant Reverberatory Furnace- similar to gas fired reverbs, but using silicon carbide heating elements over the molten bath.

Filter- a device used in the gating system to remove impurities from the molten metal.

Flask- the container in which a mold is made.

Flaskless Mold- a mold that has been removed from the flask before pouring.

Floor mold- a mold that is made on the floor, often with unrigged pattern equipment. Floor molding requires a high skill level because gates, runners and risers must often be cut in the sand by hand.

Flux- a material added to molten metal to help purify it.

Gate- the connection to the casting cavity through which the molten metal flows.

Grinding- see snagging.

Holding Furnace- a furnace in which metal is held at temperature for pouring, but which is not used for melting.

Holding Ladle- a ladle in which metal is held for pouring. It is usually very well insulated. Some holding ladles are electrically heated.

Hunter- a proprietary brand of automatic molding machine distinguished from others by the fact that it blows sand down on a pattern rather than from the side. Top blow results in better filling of pockets.

Impact Molding- a molding machine that compacts the sand under explosive releases of air pressure. Molds can be made with hardnesses up to twice those of other processes. It is also a very fast process.

Impression- a cavity in a mold.

Indirect-Arc Furnace- an electric furnace in which an arc is struck across two electrodes. The charge is melted from the resulting radiant heat.

Indirect Fired Furnace- a pot type furnace in which the flame does not impinge directly on the metal but rather on the crucible.

Ingot- a block of raw alloy.

Jacket- a rectangular form that slips over the sides of a flaskless sand mold to seal the parting line during pouring helping to avoid runouts and assure proper register of the mold halves.

Liquidus- the point at which metal begins to solidify.

Mold Weight- a weight that is placed on top of a mold during pouring to prevent the static pressure of the molten metal from lifting the cope.

Muller- a machine equipped with revolving wheels and plows that is used to mix and temper green sand.

Normalizing- a heat treat process used to increase strength and hardness by heating to a critical temperature followed by some degree of rapid cooling. Should not be confused with stress relieving.

Parting Line- The line along which a pattern or corebox is divided, or the dividing line between sections of a mold.

Pig- verb- To get rid of excess metal from a ladle by pouring it into a pig mold. noun- 1. A chunk of metal resulting from the act of pigging. 2. An ingot of iron.

Pig Iron- Ingots of virgin iron that are the product of a blast furnace or reduction process.

Pit Mold- a mold that is made in a pit dug in the floor of a foundry. Normally used for very large castings.

Pouring- filling a mold with molten metal.

Pouring Ladle- a ladle used for pouring metal into molds.

Quench- to cool rapidly by immersion in oil, moving air, water, molten salt etc..

Ram- to pack or compress sand around a pattern to make a mold.

Ram-Up Core- a core that is placed in a recess in the pattern. When the sand is rammed around the pattern the core is retained in the sand mold.

Refractory- material made of ceramics, which is resistant to high temperatures, molten metal and slag attack.

Returns- those portions of metal that are not saleable and are removed from the casting including gates, risers, runners etc..

Reverberatory Furnace- a gas fired melting unit with a roof arranged to deflect the flame and heat toward the hearth on which the metal to be melted rests.

Riser- reservoir of molten metal attached to a casting to compensate for the contraction of the casting during solidification.

Riser Sleeve- an insulating or exothermic sleeve used to keep feed metal molten longer. Sleeves increase the effective size of a riser.

Roll Over Molding Machine- a molding machine, usually used for very large molds, that clamps and rolls the flask over so the cope can be rammed.

Roto-Lift- a machine that squeezes and usually jolts sand around a pattern and that is equipped with arms that help roll over a mold after the drag is rammed so the cope can be filled and rammed.

Runner- The connection between the sprue and the gates and risers in a mold.

Sand Reclaimer- a machine used to remove spent binding materials from sand grains to make the sand useable again.

Shakeout- verb- to remove a casting from the mold. noun- 1. The machinery that shakes molds to remove the sand from them. 2. The area of a foundry where castings are removed from their molds.

Shifting- the job or the act of shifting weights and jackets from one mold to another as they are poured.

Slag- impurities that float on top of metal.

Slick- a tool used by molders to cut gates and smooth mold surfaces.

Sloping Dry Hearth Furnace- a melting unit in which metal is placed on a sloping refractory hearth until melted. The molten metal runs down the hearth into a secondary holding chamber.

Snagging- grinding flash, gates and riser contacts from castings.

Sprue- The vertical opening in the mold into which metal is poured and that directs the metal to the gating system.

Squeezer- a small machine that squeezes green sand molds to compact the sand around the pattern. Except for the mechanical squeezing, it is a mostly manual process.

Stress Relieving- a heat treat process in which stresses are removed from a casting by low level heating without causing a change in properties. Stress relieving should not be confused with normalizing.

Strike-Off- a straight edge used to level the sand with the top of the flask or corebox.

Tap- to draw molten metal out of a melting unit.

Temper- the act of mechanically activating the clay with water to give it the necessary stickiness to bond grains of sand together to form a mold. Also the state of being tempered.

Tight Flask- a flask that remains on the mold from the time of molding until shakeout.

Trap- an expansion in the gating system where the metal flow slows sufficiently to cause dross to float to the surface and prevent it from flowing into the casting.

Turntable- a mold handling machine that automatically places weights and jackets on the molds eliminating an injury prone job.

Vacuum Furnace- a melting unit in which metal is induction melted under vacuum.

Vent- a pathway provided in the mold to allow gas to escape.

St. Paul Foundry
954 Minnehaha Avenue West
Saint Paul, Minnesota 55104
(651) 488-5567  Fax: (651) 488-0908
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