Mass media finishing processes have gained widespread acceptance in many industries, primarily as a technology for reducing the
Figure 1 – This large tub-style vibratory finishing system has been fitted with dividers, so larger parts can be processed without impingement or damage from part-on-part contact.. The processing cavity can accomodate much larger parts when the dividers are removed. Note also the hinged cover for in use operation to dampen the media and part vibration generated noise.
costs of producing edge and surface finishes. This is particularly true when manual deburring and finishing procedures can be minimized or eliminated. There are a number of different mass finishing processes in common use throughout industry. Among these are barrel, centrifugal, vibratory, and spindle finishing. Vibratory systems have become the predominant method due to advantages inherent to the method in terms of ease of use, automation, and material handling. When first developed in the 1950s, these systems were typically modest in size, and were used for deburring and finish processing of smaller components. Being able to process larger batch lots of modestly sized parts was important to competitiveness.
The face of American manufacturing has changed considerably since those days. Smaller, more simply designed parts in large numbers are now almost always sourced offshore. Much of American manufacturing and machining is now concentrated on making larger, higher value, and more complex parts. As part size has grown, so has the size and processing capability of vibratory systems.
Figure 2: Parts such as this aircraft seat can be edge finished in vibratory equipment with dividers that segregate or isolate the parts from each other. Previously, these kinds of parts have not been considered practical candidates for mass finishing equipment and were deburred and finished with manual or hand held methods.. With advances in large vibratory equipment design this is no longer the limiting factor it once was. Components as large as aircraft frame structures and jet engine casings are now edge/surface finished in larger vibratory equipment despite their size and weight.
Many larger and complex parts commonly finished in vibratory equipment today would not have been considered as viable candidates for this type of automated mechanical finishing in the past. For example, 100 ft3, 200 ft3 and even 380 cu ft3 capacity vibratory systems capable of handling very large and heavy components are utilized in a number of different industries for large-part surface finishing. Vibratory finishing is an important component of a group of industrial processes referred to as mass finishing or mass media finishing. Mass finishing is a term used to describe a group of abrasive industrial processes by which large lots of parts or components made from metal or other materials can be economically processed in bulk to achieve one or several of a variety of surface effects. These include: deburring, descaling, surface smoothing, edge-break, radius formation, removal of surface contaminants from heat treat and other processes, preplate and prepaint, or coating surface preparation. These might also entail blending in surface irregularities from machining or fabricating operations, producing reflective surfaces with nonabrasive burnishing media, refining surfaces, and developing superfinish or microfinish equivalent surface profiles. All mass finishing processes utilize a loose or free abrasive material referred to as media within a container or chamber of some sort. Energy is imparted to the abrasive media mass by a variety of means to impart motion to it and to cause it to rub or wear away at part surfaces. Nearly all manufactured parts or components require some measure of surface refinement prior to final assembly, or the final finish or coating required to make the parts acceptable to the consumer or enduser. Most manufacturing companies that employ mass finishing techniques do so because of the potential economic advantages, especially when compared with manual deburring and surface finishing techniques.
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