Numerous functions and calibrations factor into developing a precise and stable mass finishing process. From media and compounds to work piece characteristics and processing times, successful finishing requires each process aspect to be carefully monitored and evaluated. When it comes to process water flow rates, poor drainage from the machine can cause quality control issues as well as equipment damage and costly downtime.
While simple in their function, drains play an integral role in regulating the flow of process water out of the machine. With the exception of intentional “flooding” of the process bowl for sharp work pieces, the same amount of compound and water entering the machine must be flushed out again. Otherwise, contaminants in the form of dirt, media, metal fines, and, frequently, oil will accumulate in the process water. Since this buildup can cause the finishing process to deteriorate and even collapse, mass finishing machines must have sufficient drainage!
With more than 80 years of experience, Rosler can expertly design mass finishing technology and troubleshoot issues to protect your system for the life of the machine.
Made from plastic such as polyurethane or stainless steel material, these drains must allow process water and media debris to be flushed from the system while retaining usable media mix and the work pieces.
While choosing the right implant material is of utmost importance, as discussed in our previous Orthopedic Implant Series post, the significance of optimum surface treatment throughout the entire implant manufacturing process cannot be overstated. This relates not only to the right surface finish, but also total compliance with the specified tight dimensional tolerances.
The functionality of an orthopedic implant is determined by the perfect match between the various implant components. This depends, to a large extent, on the surface treatment procedure(s).
Maintaining the correct compound and water flow rate into a mass finishing machine is essential for the stability and success of a process.
If inadequate compound and water are supplied to the machine, results will be more extreme and lead to unpredictable processing times, ineffective finishing, dirty work pieces after finishing, glazed media, and, potentially, a total collapse of the process.
Excessive compound and water flow can be equally problematic. Too much water and compound will slow down the movement of media and work pieces in the machine or cause a complete stop.
For example, in rotary vibrators the typical spiral movement of the media/work piece mix will give way to an uncontrolled shaking. In centrifugal disc machines, the rotating spinner will slip under the media/work piece mix with no movement at all.
Longer processing times, poor finishing results, and even a complete collapse of the process can occur.
For the best results and stability, Rosler understands that the flow rate of compound and water into the machine must be equal to the flow rate out of the machine.
For millions of individuals, orthopedic implants provide the ability to regain mobility and reduce pain. Just as surgical skill is required to implant these artificial joints, so is skillful construction and finish of the joint components themselves.
Our Orthopedic Implant Series continues with an overview of the most common materials used for these endoprosthetic implants.
To date, the most common materials have been titanium, titanium alloys, and cobalt-chromium alloys. Both materials are very tough, resistant to corrosion, highly biocompatible, and absolutely reliable.
Advancements in medical technology now allow for the development of Patient-Specific Implants (PSI). Specialized computer programs analyze x-rays, ultrasound, and MRI images to create surgical guides, tools, and implants tailored to the patient’s unique anatomy.
While still emerging, many medical industry suppliers have received FDA approval for PSI use. Like traditional implants, these implants must be carefully finished once created to ensure the work piece meets stringent medical safety standards while promoting patient comfort and long wear life.
The benefits of PSI use include shorter surgery times, better surgical outcomes, and cost savings.
True to its “apply innovation” tagline, Renishaw’s Medical and Healthcare Division has found great success in additively manufacturing PSI. Using CT scan-to-CAD software, one of the company’s most innovative advances is creating cranial plates using titanium powder.
When determining how to finish the implants to precise medical requirements and surgical demands, Renishaw trusted Rosler for help with mass finishing.
Trial and error are often the origin of innovation. As such, mass finishing and centrifuge technology have been advanced by building upon what worked and avoiding what didn’t.
With more than 80 years of experience, Rosler has extensive engineering knowledge and troubleshooting skills. An overview of the top three issues centrifuge water recycling systems experience along with possible remedies are summarized here. As always, trust a partner such as Rosler to consult on your specific issues.
Excess Oil in the System
Too much oil may be carried into the finishing system by the work pieces, for example, in stamping operations.
The excess oil will negatively affect the mass finishing process. The media might become “glazed” causing longer processing times and poorer finishing results. In addition, the finished work pieces may also be contaminated with oil residue.
Possible remedies include cleaning of the work pieces prior to mass finishing, for example, with an industrial washing machine, or switching to an alternative oil type that can be better emulsified by the compound for better discharge from the process water.
A number of factors contribute to mass finishing success. Machinery, consumables, compounds, and process water must be evaluated individually and as a whole to create optimal results and stable process conditions.
When considering the flow rate of compound and process water into the processing bowl of a mass finishing machine, careful calibration is required based on the machine type and size, finishing task, condition of the raw work pieces, and process water conditions.
For example, high‐energy machines require a much higher flow rate than vibratory finishing systems. Similarly, work pieces heavily contaminated with oil, grease, and/or dirt require more compound and water than less contaminated work pieces.
Water flow and compound dosing rates are usually determined by processing trials in the test lab of the equipment supplier. Once a finishing process has been defined, the user must make sure that the established water and compound flow parameters are precisely maintained. This requires a well-calibrated and well-maintained dosing system.
At Rosler, we draw upon more than 80 years of worldwide experience to create and maintain effective mass finishing systems and deliver precise results. Our ability to do so is thanks, in part, to understanding the importance of water flow and compound dosing.
Joint reconstruction implants are subject to the same zero-defect performance and reliability standards as any other implant. However, because two components are always interacting with each other, dimensional accuracy is of particular importance.
Within the medical industry, surface finishing experts such as Rosler assist implant manufacturers in achieving the exact finish needed for each surface of the joint.
In addition to increasing product popularity and demand for the manufacturer and providing medical professionals with safe and dependable joint replacements, ensuring that orthopedic implants have the exact finishing required enables the joint to function longer and more comfortably for the patient.
Fueled by more active lifestyles and increased life expectancy,the market for knee, hip, and other replacement body jointsis on the rise. With more than $19 billion in annual worldwidesales, implants for joint reconstruction make up nearly 40 percentof all orthopedic product sales.
Thanks to significant advancements in materials and new or improvedsurface finishing technologies, today’s artificial hips andknees can last more than 20 years, giving the recipient decadesof comfort and agility.
Parts that are finished using modern mass finishingand shot blastingmethods play a key role in extending the lifespan of orthopedic implants.
Rosler has extensive experience in these processes which often include cleaning, deburring/edge radiusing, surface smoothing, post-casting surface preparation, machining, CNC grinding, and, of course, final finishing. These finishing technologies make big differences in the quality and performance of such products.
Media selection is key in any surface finishing process since these consumables are essential “precision tools” required to achieve the specified finishing results.
Whether you are developing a new mass finishing process or changing process parameters including different work pieces, process times, and requirements, partnering with an experienced expert will help you in evaluating all process parameters.
With decades of experience developing mass finishing machines and manufacturing media and compounds, Rosler is an excellent source for guidance. In some cases, pre-tumbled media may be suggested.
What is Pre-tumbled Media?
After production, some types of pre-polishing and polishing media are pre-tumbled by the manufacturer. This process breaks sharp points and corners off individual media pieces to create smoother edges.