B+S handles a broad range of work pieces with different shapes, made of different materials, requiring different finishes, and coming from all kinds of industries. To create a streamlined and one-stop supplier, B+S chose to work with Rosler for its surface finishing equipment and consumables.
Shot blasting is a specialized surface finishing process where small metal (or mineral) pellets, called blast media, are thrown onto the surface of a work piece at incredibly high speeds. With rates of speed ranging from 200-800 feet per second, the impact on the work pieces from this process is what produces the desired surface finishing effect.
The process components of a shot blasting system include a shot blast machine, raw and finished work pieces, blast media, dust, and other byproducts. Rosler has more than 80 years of experience in developing comprehensive shot blasting systems.
For nearly a decade, Sales Representative and Interim Product Manager of Turbine Blast Equipment Zack Murray has been one of Rosler’s top shot blasting experts.
Working with customers and our global Customer Experience Centers, he helps develop and test surface finishing machines and media in addition to dialing in specific process parameters.
At times, adhering to the Rosler motto and guiding principle of “finding a better way…” can be difficult and complicated. Luckily, Murray and the entire Rosler team are committed to delivering world-class surface finishing equipment, consumables, and service in a variety of industries.
In this post, Murray shares the most challenging issue he has tackled at Rosler and how the team developed a solution.
As an expert in the shot blasting industry, Rosler knows about blade technology. All shot blasting machines require blades to propel media towards workpieces. While both straight and curved blades are used, each type offers advantages and disadvantages.
What are the Differences?
Straight blades are, as the name suggests, blades that do not have curvature when viewed from the side and do not possess tangential curvature with respect to the turbine. Curved blades are blades that have some degree of curvature when viewed from the side.
As the newer design, curved blades are generally better than straight blades, but they also have some drawbacks related to longevity, maintenance, and cost of ownership.
Replacing a shot blasting machine for a long-time customer requires finding a better way to deliver efficient finishing in a faster, smaller, and more maintenance-friendly way. That’s exactly what Rosler delivered when Linde Material Handling (Linde) returned to us for a shot blasting upgrade.
Linde is a supplier of forklift trucks and warehouse equipment and also provides technical intralogistics solutions and services. With a sales and service network spanning more than 100 countries, the company has a global footprint.
For this particular partnership, Linde’s foundry in Weilbach, Germany, challenged Rosler to supply a new shot blasting system capable of finishing and maneuvering the counterweights it manufactures for forklifts. Our solution was a sturdy foundry version of a continuous hanger shot blast machine known as the RHBD 22/27-F.
Linde continuously strives to improve its manufacturing operations. As such, the new machines had to accomplish several goals, including faster processing, more flexible material flow, optimized utilization of available space, improved access to all critical maintenance areas, and increased overall efficiency.
Knaus Tabbert AG is a leading manufacturer of recreational vehicles. The company’s innovative designs and powerful drive systems for motor homes, caravans, and panel trucks allow for safe, comfortable, and sustainable travel.
At its German headquarters in Jandelsbrunn, Bavaria, Knaus Tabbert utilizes its comprehensive experience and know-how to continuously improve the materials and designs of its vehicles as well as new manufacturing technologies such as additive manufacturing.
Seeking faster and less expensive post processing for its 3D printed prototypes, Knaus Tabbert turned to AM Solutions, a brand of The Rosler Group, to find a better way.
From prototyping to production, Knaus Tabbert needed de-powdering and cleaning operations for additively manufactured work pieces.
“On the one hand, we are using 3D printing technology for creating prototypes. On the other hand, we are also utilizing additive manufacturing for producing standard components in volume such as the bracket for an alarm system or the hinge mechanism for the swing-out shower stall,” said Mario Meszaros, Knaus Tabbert Development Engineer.
Due to their precision, efficiency, and economy, mass finishing and shot blasting are an indispensable part of the finishing process for a wide variety of orthopedic implants in different manufacturing stages.
These flexible machines can handle general cleaning; deburring; surface smoothing after casting, forging, stamping, machining, and heat treatment; surface preparation for polishing or coating; and the placement of the final finish on all kinds of implants and medical devices.
With an experienced partner such as Rosler, these processes are also capable of adapting to emerging trends with proper testing and processing trials.
Evolving Technology & Outlook
Orthopedic implant manufacturers are at the cutting edge of medical technology. New materials and manufacturing techniques and technologies are constantly evaluated to improve the performance and longevity of the implants and reduce the manufacturing cost. Two examples are the increased use of ceramics as base material or coating and additive manufacturing.
Blast cleaning is uniquely capable and efficient at delivering the pre-coating surface preparation required for components that must be able to withstand severe ambient conditions including heavy equipment for construction and mining, agricultural machinery, transportation and material handling equipment, and railway equipment and rolling stock.
Based in Enschede, Netherlands, the company designs and produces numerous products including placement systems for container pads. Its customers largely work within the material handling, offshore, and transportation sectors.
Like mass finishing, shot blasting is an exceptionally versatile surface treatment technology. Its applications range from general cleaning after casting and forging to shot peening and, even, cosmetic blasting for placing a fine, matte finish on the work pieces.
For shot blasting orthopedic implants, Rosler recommends mainly air and occasionally wet blasting systems. In each process, blast media is accelerated by compressed air and thrown at the work pieces through a blast nozzle, creating an extremely precise blast pattern compared to turbine blasting. Another advantage of air blasting is that it can be used with metallic, mineral as well as organic blast media.
These attributes and many more make this surface finishing method particularly useful in the medical industry.
Examples of Shot Blasting
Shot blasting is an impact system in which small metal or mineral pellets are thrown onto the surface of a work piece at speeds of 200-800 feet/second. The impact on the work piece surface produces the desired cleaning, peening, or texturing effect.
For medical applications, mainly air and wet blast systems are used which generally make a surface rougher. The smoothest finishes achieved with shot blasting are about Ra = 16-32 microinches (= 0.4 to 0.8 μm).
Unlike dry blasting that only uses a solid abrasive media, wet blasting processes use a slurry of water with the shot blasting media. This greatly cushions the impact energy on the work pieces, providing gentler, yet effective results for delicate work pieces. The achieved surface finish and appearance will also differ between wet and dry processes, even when the same media type and size are used.
With more than 80 years of experience worldwide, Rosler can supply both the machines and media best suited for your wet blasting needs.
Common Media Types
As long as it is heavier than water and not water soluble, practically any media used for dry blasting can be used for wet blasting.
It is important to consider the usefulness of the media compared to its cost. While a cheaper or longer-lasting media may be available, it may also require additional processing time to accomplish the desired surface finishing. Selecting the most appropriate media for your process requires balancing initial costs with overall results.