Finishing off your casting.I made a casting, now what do I do with it? When we think of metalcasting technology, our minds go through the typical casting process technologies--melting, metal preparation and cleanliness Cleanliness See also Orderliness. Cleverness (See CUNNING.) Berchta unkempt herself, demands cleanliness from others, especially children. [Ger. Folklore: Leach, 137] cat continually “washes” itself. , molding equipment, sand systems, pouring, gating, solidification so·lid·i·fy v. so·lid·i·fied, so·lid·i·fy·ing, so·lid·i·fies v.tr. 1. To make solid, compact, or hard. 2. To make strong or united. v.intr. and other technologies that are utilized in the production of cast metal components. However, a big part of the production of a cast metal component begins after these technologies--after the completed casting comes out of the mold. In many cases, these post-casting technologies comprise a considerable portion of the final cost of the cast component. This work is sometimes referred to as the "cleaning room" processes. While many metalcasters offer value-added services A value-added service (VAS) is a telecommunications industry term for non-core services or, in short, all services beyond standard voice calls and fax transmissions. , such as machining, special finishes and polishing, as part of their post casting finishing, this column will focus primarily on the rough grind and basic finishing operations. Traditional Finishing After the casting is removed from the mold materials, the gating and risering system is removed by sawing, breaking or some other means. Usually, this leaves some of the gate connections, mold parting lines and other excess material on the casting for later removal by abrasive abrasive, material used to grind, smooth, cut, or polish another substance. Natural abrasives include sand, pumice, corundum, and ground quartz. Carborundum (silicon carbide) and alumina (aluminum oxide) are important synthetically produced abrasives. grinding grinding, process by which surface material is removed from an object, usually metal, by the abrasive action of a rotating wheel or a moving belt that contains abrasive grains. . Bonded abrasives abrasives Sharp, hard materials used to wear away the surface of softer, less resistant materials. Abrasives are indispensable to the manufacture of the highly precise components and ultrasmooth surfaces required in the manufacture of automobiles, airplanes and space , such as grinding wheels and other hard stone-like products and coated abrasives (abrasive bonded onto a cloth backing like sand paper), are commonly used in both floor-mounted machinery and hand-held tools for casting finishing. The different operations and tools used in post casting finishing in the typical cleaning room have traditionally been manual, and the cleaning room has been a very labor intensive Labor Intensive A process or industry that requires large amounts of human effort to produce goods. Notes: A good example is the hospitality industry (hotels, restaurants, etc), they are considered to be very people-oriented. See also: Capital Intensive, Trading Dollars operation. However, newer automation technologies are now being utilized to improve the consistency and throughput of metalcasting cleaning room processes. Automated Finishing One of the primary benefits of automation can be improvements in quality, particularly improved consistency and reduced variability. Each automated movement is programmed and consistent, so the casting can be oriented o·ri·ent n. 1. Orient The countries of Asia, especially of eastern Asia. 2. a. The luster characteristic of a pearl of high quality. b. A pearl having exceptional luster. 3. to the grinding wheel at the same location and pushed against the wheel at the same force each time. Newer vision systems can scan castings and compensate for variations in casting geometries. While some automated systems may require a higher volume of castings to justify the investment, applications are available that can economically be applied in the small to medium jobbing metalcasting facility, as well. Following is a list of automated finishing systems: * Pressure Assisted Grinding Fixtures. New abrasive materials are designed to remove metal at a very high rate, but traditional human operated grinding cannot produce the pressure required to maximize the cut rate of these materials. Adding hydraulic power to push the casting into the abrasive can greatly increase the cutting capacity of the grinding belt or wheel, removing large or thick gate and riser connections quickly. * Trim Press. To remove gates, riser connections and parting lines, an operator would typically pick up a casting and take it to the grinding wheel, where he then would have to move the part to different orientations to complete the grinding operation. The trim press can do this in one operation, consolidating the movements of the hand operator. The trim press especially is useful for high volume castings where the cost of the fixture can be amortized more easily. * Automated Finishing Cells. Several versions of automated cells are available commercially, but most operate on a similar concept--multiple cutting and grinding operations are enclosed en·close also in·close tr.v. en·closed, en·clos·ing, en·clos·es 1. To surround on all sides; close in. 2. To fence in so as to prevent common use: enclosed the pasture. into one cabinet. The casting is put into a fixture (either manually or by robot), and the cabinet door is closed for safety and to contain noise and dust. The machine is programmed to move the casting through several cutting and grinding processes on both vertical and horizontal planes horizontal plane n. A plane crossing the body at right angles to the coronal and sagittal planes. Also called transverse plane. horizontal plane until the grinding operations are completed. * Robotics robotics, science and technology of general purpose, programmable machine systems. Contrary to the popular fiction image of robots as ambulatory machines of human appearance capable of performing almost any task, most robotic systems are anchored to fixed positions . Cleaning room operations provide an ideal application for robotics. Robots can be used to pick up and move a casting to the grinding wheel or can pick up a hand tool and move it to the casting. Robotics brings the added benefit of improving consistency and quality. |
|
||||||||||||||||
Printer friendly
Cite/link
Email
Feedback
Reader Opinion