by Contributing Editor: Dave Davidson, Deburring/Finishing Technologist | 509.230.6821 | dryfinish@gmail.com | https://about.me/dave.davidson
If you have parts that need edge or surface finishing improvement and would like to have FREE sample part processing and a quotation developed for finishing the parts please contact Dave Davidson at dryfinish@gmail.com I can also be reached at 509.230.6821 Information about equipment for bringing Centrifugal Iso-Finishing Equipment to your facility is also available...
Centrifugal isotropic finishing
Centrifugal barrel finishing (CIF) is a high-energy finishing method, which has come into widespread acceptance in recent years. Although not nearly as universal in application as vibratory finishing, a long list of important CBF applications have been developed.
Above: Final dry process polishing o automotive engine component
Similar in some respects to barrel finishing, in that a drum-type container is partially filled with media and set in motion to create a sliding action of the contents, CBF is different from other finishing methods in some significant ways. Among these are the high pressures developed in terms of media contact with parts, the unique sliding action induced by rotational and centrifugal forces, and accelerated abrading or finishing action. As is true with other high energy processes, because time cycles are much abbreviated, surface finishes can be developed in minutes, which might tie up conventional equipment for many hours.
Centrifugal Barrel Finishing principles – high-intensity finishing is performed with barrels mounted on the periphery of a turret. The turret rotates providing the bulk of the centrifugal action, the barrels counter-rotate to provide the sliding abrasive action on parts.
The principle behind CBF is relatively straightforward. Opposing barrels or drums are positioned circumferentially on a turret. (Most systems have either two or four barrels mounted on the turret; some manufacturers favor a vertical and others a horizontal orientation for the turret.) As the turret rotates at high speed, the barrels are counter-rotated, creating very high G-forces or pressures, as well as considerable media sliding action within the drums. Pressures as high as 50 Gs have been claimed for some equipment. The more standard equipment types range in size from 1 cubic foot (30 L) to 10 cubic feet, although much larger equipment has been built for some applications.
Abone: Multi-step operations with a Model HZ-60 centrifugal iso-finishing machine to produce highly polished surfaces. Process recipes for various alloys have been developed to produce low micro-inch polished surfaces for medical, aerospace, auotmotive, motorsports, dental and jewelry parts among others.
Media used in these types of processes tend to be a great deal smaller than the common sizes chosen for barrel and vibratory processes. The smaller media, in such a high-pressure environment, are capable of performing much more work than would be the case in lower energy equipment. They also enhance access to all areas of the part and contribute to the ability of the equipment to develop very fine finishes. In addition to the ability to produce meaningful surface finish effects rapidly, and to produce fine finishes,
CBF has the ability to impart compressive stress into critical parts that require extended metal fatigue resistance. Small and more delicate parts can also be processed with confidence, as the unique sliding action of the process seems to hold parts in position relative to each other, and there is generally little difficulty experienced with part impingement. Dry process media can be used in certain types of equipment and is useful for light deburring, polishing, and producing very refined isotropic super-finishes
Below: Centrifugal Iso-Finishing Equipment and some typical finished parts.
FREE Sample Finishing Available. CONTACT Dave Davidson at dryfinish@gmail.com to make arrangements.
