Regardless of the industry, the selection of media and compounds utilized in mass finishing can elevate or hinder finishing results. The handling of effluents – used process water – also factors into a process’ efficiency and end results.
With more than 80 years of experience, Rosler understands the demands of the forge and foundry industries specifically and how to achieve precise and consistent finishing results by combining the latest technology, well-designed machines, and consumables.
This installment of the Forge & Foundry Blog Series highlights how careful media and compound selection along with proactive handling of effluents assist in producing mass finishing efficiencies.
Ingredients for Success
Media and compounds are more than just “rocks” and “soap” thrown into a mass finishing machine. Instead, these consumables are sophisticated tools that can make a mass finishing process a success or a failure.
Rosler Metal Finishing has decades of experience in the forge and foundry industries, especially when it comes to mass finishing for die-casted work pieces.
Our Forge & Foundry Blog Series continues with an overview of our top five mass finishing machines for precise cleaning of die castings.
Standard Rotary Vibrators
Media and parts are placed into a circular processing bowl in standard rotary vibrators. The energy from a vibratory motor causes the media and parts to freely tumble over each other. Some models are equipped with an internal separation device for separating the finished work pieces from the media.
Rotary vibrators can be used for batch and continuous feed processing.
Rosler’s standard rotary vibrator models include the models EC, Euro, A, and R.
Ideal Work Pieces — Small to fist-sized die-castings such as shoe buckles, furniture fittings, gear shifter forks, electrical components
Our Forge & Foundry Blog Series continues with an overview of our shot blasting machines most frequently used on these specific types of work pieces.
It is important to understand your work piece and process requirements including whether components will be processed continuously or in batches. When it comes to finishing forgings, non-sand castings, and powdered metal components, our shot blasting machines are divided into three categories based on how the work pieces are fed into the machine: continuous, batch, and specially engineered shot blasting machines.
Continuous Shot Blasting Machines
RMBD Continuous Tumble Belt Machine
The high-capacity, continuous feed RMBD is available in a heavy-duty version for large forgings and castings, which is equipped with 6 x 40 HP turbines, a steel-slatted work piece transport belt, and a magnetic separator.
With extensive experience in the forge and foundry industries, Rosler Metal Finishing understands that no two shot blasting processes and work pieces are alike. With that in mind, we continue our Forge & Foundry Blog Series with an overview of our machines offering excellent finishing for sand castings.
If you demand precise, repeatable results when shot blasting sand castings, consider the following machines. As always, the experts at Rosler are also available to develop a customized machine to accommodate your unique work pieces and challenges.
RMBD Continuous Tumble Belt Machine
The high-capacity, continuous feed RMBD is available in a heavy-duty version for foundry applications equipped with 6 x 40 HP turbines, a steel-slatted work piece transport belt, and a magnetic separator.
Our Forge and Foundry Series continues with a deeper look at sand castings. While more than 60 percent of all metal castings are made with a sand casting process, the specific shot blasting machines used to remove surface contaminants vary. Rosler Metal Finishing is uniquely qualified to identify the right shot blasting machine for your process and can help determine what settings and media will produce the best results with every cycle.
Sand Casting Basics
Sand casting, also known as sand molded casting,
is a metal casting process using different kinds of sand as mold material. The
sand is usually “glued” together with a bonding agent like clay, water, oil,
resin, or sodium silicate.
A sand mold consists of two or more sections.
Liquid metal is poured into the cavities formed by the mold.
Once cooled, sand molds pass through a shakeout
device, where they are destroyed to extract the metal castings. The raw
castings then undergo a fettling procedure, where sprews, gates, runners, and
risers are separated, and coarse burs are removed.
When a casting is produced, by-products are
generated. Small pieces originating from spills, gates, runners, and risers are
returned to the casting process as recycling material. To ensure a consistently
high overall quality of the raw material, it is essential that this recycling
material is perfectly clean without any sand, casting shell, or other residues
on the surface.
Subjecting these by-products to a blast cleaning process from Rosler Metal Finishing before they are re-melted offers many advantages. Besides the resource-saving use of raw materials, the effective cleaning of the recycling material increases the uptime of the smelting furnaces by significantly reducing the amount of unwanted slag.
Components made from steel, nodular cast iron, and
grey iron can be processed by mass finishing equipment.
Getting castings and forgings ready for the subsequent processing steps presents some of the toughest surface finishing challenges. Shot blasting machines can handle all of these tasks from removing residual sand, casting shells, flashing, die marks, or scale. Whether cast iron, steel, stainless steel, super alloys, titanium, aluminum, zinc, or magnesium, the comprehensive portfolio of Rosler Metal Finishing blasting systems for the foundry industry enables the optimal process for any requirement.
Shot blasting is an essential part of most forge
and foundry operations and has been used since the late 1800s. This specialized
surface finishing process throws small metal (or mineral) pellets, called blast
media, onto the surface of a work piece at incredibly high speeds, ranging from
200-800 feet per second. The impact on the work pieces from this process is
what blasts the contaminants from the parts and produces the desired surface
When properly applied prior to finishing, blasting
achieves three key aspects of the finishing process:
Cleans and descales
Creates a uniform
texture on the part and blends the surface
Automatic blast cleaning with high flexibility for production lines. A robotic blaster is a combination of a shot blasting unit and a multi-axis robot specially engineered to suit specific applications. It can be deployed for different blast cleaning tasks – from deburring and desanding all the way to evidenced documented shot peening.
Typically automobile manufacturers utilise this highly efficient, compact and noise protected blast system to deburr and surface finish bell/gearbox housings made of magnesium alloy in extremely short cycle times, as low as just 26 seconds. In order to handle the components from two parallel pressure die casting lines and place them into the shot blasting unit, the robot can be equipped with a double gripper. In the blast cabin, the bell and gearbox housings are shot blasted by six high performance and efficient blast wheels.
While today’s foundry operations are mostly automated, surface treatment frequently still involves a lot of manual labour resulting in one of the most costly operations within a foundry. Automated systems tailor-made to the unique requirements of desanding, deburring, cosmetic finishing and overall surface finishing of raw castings not only significantly reduce costs but also increases process safety.
Regardless of how a component is cast, tasks such as desanding, deburring, and surface cleaning are often still carried out manually. Not only are they extremely time consuming and highly labour intensive but the quality of manual blasting strongly depends on the skills of the person who is blasting, resulting in a process that is neither consistent or documentable. High quality shot blast results are however a crucial aspect for any foundry product as well as being an important competitive factor.