Glossary of Casting Terminology "C"
This glossary lists in alphabetical order casting industry terms and their explanations.
| Word/Expression | Explanation |
|---|---|
| cast iron | A ternary alloy of iron that contains a carbon component of 2.14 to 6.67% and a silicon component of around 1 to 3%. The types of cast iron include gray iron, ductile iron and malleable iron. Compared to steel, cast iron has a lower melting point and is easier to use in manufacturing. |
| castability | The ability of a casting design and properties of the materials involved for producing a casting with excellent quality, such as excellent fluidity and/or shrinkage characteristics. |
| casting | The act of pouring a molten metal such as aluminum or iron into a casting mold or sand mold to fill it. |
| casting burr | Thin extra portions on a casting formed and solidified by the molten metal entering the narrow gaps between the two molds. Burrs are more likely to form if the die matching is insufficient. |
| casting design | The design and shape of the cast piece that fulfills all engineering requirements. This includes ensuring casting feasibility, i.e., viability in each of the downstream processes, and the requisite consideration of casting methods for improving total QCD (quality, cost, delivery) levels with regards to parting, part shape, the riser, runner, gate system and other conditions. |
| cavity insert | A mold component for forming a shape smaller than a mold insert. It is installed by configuring the cavity to have a divided structure and setting the cavity insert in the mold insert area. It is installed to enable partial replacement of parts in areas of the cavity susceptible to erosion or gas venting. |
| centering | The process of adjusting the center axis of a casting or other work piece when a three-jaw chuck is used during lathe machining or the like in order to ensure overall machining accuracy. |
| central melting furnace | A furnace solely dedicated to melting metals for casting and set in a single location. Casting factories typically use a central melting furnace or individual melting furnaces positioned for each casting machine. |
| chamfering | The process of creating a beveled edge where two surfaces/faces connect, such as angled edges and the openings of casting or machining holes. This can be done either through the shape of the material itself or machining a finished casting. Chamfering is applied to reduce the likelihood of human injury, damage due to impact with other objects and burrs generated by machining work. |
| chill | In iron casting, this results in a hard and brittle metallurgic structure with precipitated cementite (Fe3C). Also, placing a mold or chill block on a portion of a sand mold to increase the hardness of that portion of the casting through rapid cooling can cause the metallurgic structure to transform into white cast iron (cementite). In aluminum casting, a rapidly chilled metallurgic structure can also be called “chill.” A chill layer generated in a sleeve in die casting becomes a broken chill layer, causing a casting defect. |
| chisel | A tool made of steel and used with a hammer for shaping metal. Its sharp end is flat and can remove a thick burr or the like when struck on the other end by the hammer. |
| circularity; roundness | The degree of deviation from a true circle. The Japanese Industrial Standards (JIS) define this as, “the degree of deviation of a circular geometry from the geometrically true circle.” |
| clamp | A claw-shaped part used for fixing a cast piece firmly to a jig. |
| clamping cylinder | The cylinder used for opening and closing the mold fitted to a casting machine. It also serves to “clamp” the mold closed and prevent it from opening when the molten metal is injected into the mold at high pressure. |
| clamping force | The maximum force for a casting machine to close a mold. |
| clearance | When casting with metal molds, sand molds, etc., this is the small space created between the mold halves that meet in order to achieve optimal dimensional accuracy in the final cast piece. |
| clevis | A U-shaped link with holes at the ends of its two prongs to pass a pin through to serve as a coupling joint or fastener. |
| clogging | When the fine spaces in textile or mesh filters become blocked with dirt, dust or other debris. |
| coarse screw thread | The most commonly used type of screw thread. With a metric screw, the space between threads (pitch) is expressed in millimeters and it is called a coarse screw thread. There are also fine screw threads that have a different pitch size. |
| coating thickness | The thickness of a coating. In gravity die casting and low-pressure die casting, the coating thickness of the mold facing is important. |
| coating thickness tester | A device for measuring coating thickness. |
| cold shut | A casting defect in which flows of molten metal poured into the mold do not fuse together completely, appearing as marks or lines. This defect may occur only on the surface or penetrate through the material. Possible causes include low temperature of the molten metal poured, extensive generation of oxidized film on the material surface, the mold core generating excessive gas and numerous locations with air pockets due to irregular metal flow into the mold. |
| combustion | An oxidation reaction in which a combustible material burns in the presence of air or oxygen while generating light and heat. |
| compatibility | The quality of being effectively usable without problems if replacing or working in combination with other parts or devices. |
| component | The element(s) a compound or the like is composed of. |
| compressed air | Air compressed to 0.5–0.6 MPa, etc., from the standard 0.1 MPa (atmospheric pressure) using a compressor. |
| contamination | Impurities such as cast sand or machining chips that remain in a cast product. |
| contraction | The shrinkage of a cast piece when it returns to room temperature following the casting process. The size difference between a mold and a casting at room temperature is called “shrinkage allowance.” |
| convex | A shape that is raised in relation to a flat surface. |
| conveyor | A transport system providing the power to carry (convey) a constant flow of materials like casting sand or cast pieces. Conveyors come in a number of types depending on the power source and components used, including belt conveyors, chain conveyors, screw conveyors and vibration conveyors. |
| coolant | A lubricating oil used in machining when cutting or polishing. |
| cooling tank | A tank filled with water specifically for cooling castings. With heat treatment, it is used for cooling the work piece following solution treatment. |
| cooling tower | A tower tank set up outside to cool the water used as coolant, diffusing the heat before recirculating the water back for use again. |
| cooling water | Water used for cooling heated machines, molds, etc. |
| core | When producing a product that requires a hollow portion, a core is placed inside a casting mold to form this hollow portion. Generally, most cores are made in a casting mold using resin coated sand, with shell molds, cold boxes, CO2, or furan-based resins and the like used. |
| core box | A mold used for making cores. With cores for shell molding, they are pre-heated either by an electric heater or by gas. |
| core crack | A casting defect that occurs when a core breaks due to some kind of force. This may occur during transportation, but if it happens while casting, the cause can include molten metal pressure, thermal expansion, or some other external force. |
| core pin | A pin set within a product shape (cavity) for forming a hole or a penetrating shape in a casting. |
| core print | A section of the foundry pattern with a different shape from the core and is used for positioning the core being set into the casting mold. |
| core sand | A casting core is typically composed of a resin binder and sand. There are many types of core sand, but in Japan, shell molding using resin coated sand is common. This method uses natural silica sand of various places of production according to the application. For special applications, artificial silica sand is used in some cases. |
| core separation | A core must maintain its designated position and dimensions with a core print and the like, and core separation is when the core floats or becomes dimensionally defective due to some kind of external force like the molten metal. |
| core shift | This is when the core shifts from its correct position for some reason, causing dimensional defects in the cast piece, such as improper wall thickness. |
| corner R | The radius (shape) of the convex part of a cast piece. |
| corrosion resistance | The capability of a metal, etc., to resist corrosion. Methods to measure corrosion resistance include salt spray tests and the like. |
| corrosive gas | A gas that induces or accelerates corrosion, such as hydrogen sulfide, sulfurous acid, chlorine or ammonia. |
| coupler | A part for connecting pneumatic circuits or hydraulic circuits together with a single action. |
| crack | A casting defect caused by shrinkage or strain. Cracks due to shrinkage may appear in the corner sections of a casting and the like or in the areas of final solidification with an overheated mold. Cracks from strain may appear due to the tensile stress of constraints at the two ends of a casting's smaller cross sections during solidification shrinkage. |
| crack (imiri) | The appearance of a crack in a casting. It is also called imiri in Japanese, a word attributed to the regional dialect of the Yaizu region in Shizuoka Prefecture, but is also called this in general throughout the prefecture. |
| crucible | A heat-resistant container made from graphite or cast iron for melting and/or holding a molten metal. |
| cycle | A unit indicating the number of times a casting machine or the like performs one complete application of its operational processes, such as pouring, solidification and casting removal. |
