Before the “dirty” process water coming from a mass finishing operation can be discharged to sewage, it must be cleaned to meet the legal discharge limits for hazardous materials. Likewise, for cycling the water back to the mass finishing process, the process water must also be cleaned. Uncleaned process water would cause a mass finishing process to collapse very quickly.
Rosler has more than 80 years of surface finishing expertise. In that time, we’ve developed countless efficiencies in both the design of our equipment and the processes they support. Centrifuge technology has long been an effective and cost-efficient tool, not only for cleaning the process water, but also for reusing it for the actual mass finishing operation.
Previous Cleaning Methods
To a large extent, this technology has replaced traditional waste water cleaning methods. Until recently, the most common cleaning systems for mass finishing applications were settlement tanks and flocculation (“floc & drop”) systems.
As a result, media wears down over time, losing its shape, size, and effectiveness. Known as undersized media, this worn media must be discharged and replaced with fresh media to ensure proper processing and safety.
Whether a process uses ceramic, plastic, or polishing and drying media, Rosler stresses the importance of monitoring media levels and the mix of new and worn media for precise and safe mass finishing results.
Mass finishing machinery is a major investment for most companies. Proper maintenance and preventative repairs over the life of these useful and necessary machines will greatly improve the return on such investments, drive productivity, and extend the working life of the equipment itself.
Rosler stresses the need to regularly inspect the linings of vibratory tubs and troughs to identify repairable issues before permanent damage occurs.
To effectively finish work pieces, media must be matched to the specific finishing task and initial state of a work piece. For example, media used for deburring/edge radiusing and surface grinding can be very abrasive. If not properly protected by a suitable wear lining, the steel construction of a work bowl would be completely worn through in a few hours by contact with the media and work pieces.
Maintaining the right ratio of media to work pieces is essential to achieving precise, repeatable results in mass finishing processes where work pieces and media loosely tumble in the processing bowl.
Ensuring that the work pieces are properly embedded in the media allows the media to perform its designated grinding or polishing function as well as cushioning the work pieces from damage caused by part-on-part impingement.
The standard ratio of media to work pieces is around 3-to-1 by volume – meaning that the mix is 3 parts media to 1 part of work pieces – but the exact ratio varies based on the aggressiveness of finishing required as well as the work piece’s material, shape, size, weight, and delicacy or lack thereof.
The importance of the media selection in any surface finishing process cannot be emphasized enough. These consumables are essential “precision tools” for achieving the specified finishing results.
Selecting the right media is a complex task. That’s why you should consult an expert such as Rosler for guidance.
Even after a mass finishing process has been established, the media status must be constantly monitored and, if necessary, corrected. When different work pieces are processed or finishing tasks are altered, exchanging the currently used media type with another may be required.
Careful and collaborative media selection is crucial to a mass finishing success.
When most companies take on capital expenditure projects such as purchasing mass finishing equipment, very careful attention is paid to investing in the most productive, cost‐efficient equipment as possible to achieve the best possible quality. Operational efficiency is often another story.
Once the equipment is up and running routine takes over and less attention is paid to keeping the equipment operating at its peak performance. Whether the machinery is never calibrated to reach its fullest potential or the on-going process is not carefully monitored once the process is dialed in, lacking operational focus can be costly and counterproductive. Figuratively speaking, poorly managed mass finishing operations are pouring money down the drain!
Rosler works with its clients to ensure that our machinery delivers initial success and continues to provide precise, repeatable results long into the future by promoting operational attention and heading off costly mistakes.
Consequences of Inattention
For mass finishing processes, the lack of operational focus may take many forms individually or simultaneously, including:
When it comes to high-volume production of complex aluminum die-castings, Kovolis Hedvikov a.s. (Kovolis) is a sought after partner by numerous car manufacturers and their suppliers. To expand its capacity and achieve more flexibility in the overall manufacturing process, the company purchased a continuous flow vibratory finishing system from Rosler designed to handle a wide work piece spectrum and custom engineered to fit into the available space at the customer’s premises.
Founded in 1816 as an ironworking operation, Kovolis has focused entirely on aluminum die casting since 1945. Today, Kovolis produces components from nine different aluminum alloys weighing between 7 oz (200 grams) and 18 lbs (8 kg) with different casting technologies including vacuum investment casting and rheocasting.
Their product range includes brakes, power steering systems, turbo chargers, and compressors for air conditioning systems. Kovolis customers are renowned car manufacturers and tier-1 suppliers that also utilize the company as an important partner for product development, machining, heat treatment, and surface finishing services.
The R 150 DL-2 was an excellent choice for LINK’s new “bi-mobil” hip implant. The implant offers patients a higher degree of mobility by inserting a movable PE joint in the acetabular cup. The PE-joint in turn is clamped to the ball of the hip stem. To minimize friction and prevent premature wear, the inside of the cup requires an extremely smooth surface, which can only be achieved with a high gloss polished finish—something the R 150 DL-2 easily achieves where other surface finishing companies failed.
Available as rotary vibrators and centrifugal disk finishing systems, Rosler’s part-on-part finishing machines can accommodate various ammunition pieces including blanks, cups, deep-drawn casings, cartridge primers, and bullets.
While the manufacturing step and finishing operation of each component varies by work piece and desired result, common mass finishing operations for ammunition based on the specific work pieces are summarized below.
In addition to viewing work piece impingement as an asset, this type of mass finishing also eliminated the need for ceramic, plastic, and other types of media. The only additives required for such part-on-part finishing are water and the respective compounds.
The applications and benefits of each machine provide a range of part-on-part mass finishing uses for sturdy parts in bulk. Let’s compare their designs.
WTA Rotary Vibrators
Rosler developed special WTA rotary vibrators especially for part-on-part processing. These machines not only allow running the finishing/washing process, but also the subsequent drying stage in one single machine.