There has been a lot of discussion surrounding the use of traditional mass finishing for post processing of Additive Manufactured parts. Traditional mass finishing, (centrifugal barrel, disc, vibratory bowl, etc.), is not well suited for complex geometries. The gross material removal and loss of geometry to critical dimensions is pronounced on outside dimensions while in some cases leaving the inside dimensions virtually untouched. This is the case with subtractive manufactured components as well. When considering finishing options, engineers have either allowed for dimensional changes from finishing or opted to hand finish, discriminately, to avoid any changes in final dimensions.
Processing of Complex Geometries with
Walther Trowal has developed the TROWAL-ADD® process utilizing new technology that excels in consistently producing highly homogeneous surface finishes on work pieces with complex geometries and, for example, thin, fragile vanes. As in the blisk segment pictured abovet or femoral components with a “box.” Even difficult to reach corners receive a perfect finish.
The performance of the MV machine differs from all other types of mass finishing technologies. Drag and Spindle finishing are directional. Those technologies will work heavily on the exposed areas of the part, leaving some areas worked much less and an overall uneven result. Vibratory Bowl, Centrifugal Disc, Centrifugal Barrel will leave an isotropic finish but will work the exposed areas while in some cases, leaving more difficult to reach areas virtually untouched. The MV machine produces an evenly, isotropic surface finish across the whole of a part – even in difficult to reach areas. This makes it an ideal machine for aerospace blisks and discs, Femorals with a “box” area, or even for finishing the internal areas of a manifold.
The Walther Trowal MV technology is uniquely suited to post processing of additive manufactured components, with its ability to work the part evenly and not remove critical features before achieving the finish.
Depending on where your starting Ra is, and whether you are just refining the surface or looking to super-polish, there may be a two-step process to reach your goal.
If the complete aerospace blisk was additive manufactured to a finished dimension, we could process it in our MV machine utilizing the build plate as a fixture. The components would be finished prior to removal. Should your components require post process machining, or are not additive manufactured, we could easily finish in the same equipment utilizing fixturing
Benefits of the TROWAL-ADD® process:
· Consistent and repeatable grinding and polishing results
· Excellent finishes on difficult to reach surface areas
· Homogeneous, perfectly isotropic surface finish
· Removes any chance of part impingement during the process
· Even the most intricate work piece contours are maintained
· 24-hour operation, without any operator intervention, is possible
Walther Trowal has been the Technology Leader in the Mass Finishing Industry since 1931 and has invented most of the equipment in our industry through the years.
Plan a trip to our Process Development Test Lab in Grand Rapids, MI, where Walther Trowal helps to develop processes that not only meet your part specifications and production flow but also offers complete systems with closed loop, automated, wastewater recycling.
Contact us today for free test trials on your components.