A white paper from Walter Surface Technologies shows how its new Wi-Fi-enabled passivation tester is a striking example of innovative sensor technology, web-enabled networking, cloud-based platforms and mobile apps coming together to support the metalworking industry in the digital age. It’s a compelling case study of data-driven manufacturing in action on the shop floor.
Many metalworking companies apply processes and treatments to workpieces in the course of producing them for customers. One example is passivation, a process to make stainless steel corrosion resistant. Testing passivated workpieces to be sure the process was complete and effective can be a challenge. However, any company concerned about quality control and inspection will be interested in this discussion of how a handheld wireless diagnostic tool, Walter Surface Technologies’ Surfox Smart Passivation Tester, is an example of the Industrial Internet of Things at work. The device measures the chromium oxide layer found on the surface of stainless steel. This layer protects the metal from corrosion and rust. Within seconds, the tester syncs a numeric value of the quality of the passive layer to a smart phone and uploads the test results to the cloud.
The device integrates both the physical and digital worlds and provides real-time data that can be shared with customers. Using this device as an example, the white paper puts the development and implementation of web-enabled technology into a real-world context.
As a plus, the paper includes a primer defining many of the most popular buzzwords related to the Internet of Things, Industry 4.0 and Big Data is also handy and informative.
The bosses on this machined turbine engine combustor case, showcased at an Okuma America open house last year, were produced on a laser deposition machine from RPM Innovations. The two companies foresee a big future in hybrid additive/subtractive cells.
“While desktop printers and entrepreneurs may grab the headlines, manufacturers are also pushing 3D printing to its limits and are prime movers in ushering the technology to higher maturity levels.”
Among the 71 percent (!) of manufacturers that are currently applying additive in some way (up slightly from the 67 percent reported in a 2014 PwC study), the trend is toward less experimentation and more actual application, whether for prototyping or production.
The number of manufacturers that expect additive technology to be used for high-volume production in the next three to five years has grown from 38 percent to 52 percent since the last PwC study, while those expecting it to be confined to low-volume, specialized products slipped from 74 percent to 67 percent.
Although most agree that additive technology could disrupt the industry, they’re split on what exactly those disruptions might be. The most popular scenarios include supply chain restructuring, threats to intellectual property and changed relationships with customers.
The full study offers more detail on all of these trends, and includes a list of questions to help manufacturers determine how best to take advantage of additive technology. It’s certainly worth a look.
Online marketing is a necessity for job shops. In fact, we’ve written about it several times. (This column and this later column are just two examples.) Aside from investing in your website, blogging, posting to various social media channels and perhaps sending mass emails, what can you do to promote your machine shop?
Gilman Precision of Grafton, Wisconsin, took an interesting new approach that I haven’t seen before. The company partnered with Google Street View service to provide a virtual tour of its facilities. You can view it on their website or on Google Maps. This tour lets you navigate through Gilman’s main doors and around the factory, including its class 10,000-level spindle clean room.
A virtual tour is a great way to show potential customers (and magazine editors) a little about your shop, machines and capabilities.
Tell me, are you using Google Street View service at your shop?
One of the most popular conference tracks at the PMPA National Technical Conference were sessions in which prints—and often part samples—with certain key parameters were provided to groups for roundtable discussions of the best way to machine the part.
When visiting a shop, I am particularly interested in the process behind determining the best way to machine a part from the prints provided by the customer. So many things must be taken into consideration—in fact, nothing can be left to chance. In order to meet the customer’s requirements, and to reach the lowest cost per part in order to win the bid, here are the top 12 considerations I’ve noted, although there are certainly more depending on the part in question:
Best machine tool/process
Risks/benefits of each process
Geometry/features of the part
How to machine with fewest setups/lowest cycle times
The best approach to workholding/fixturing
Best type of stock to use
How much cross-drilling and backworking, etc., will be required?
Best means of conducting measurement/inspection
Chip generation (types, amounts, etc.)
What is the purpose of the part?
How will deburring be accomplished?
What type of surface finish is required?
I was able to witness an especially intense example of this exercise at the recent Precision Machined Products Association (PMPA) National Technical Conference in Grand Rapids, Michigan, April 9-12 (go here for my review in Production Machining magazine). In addition to the presentations made during the three-day event—Rotary Transfer, Speeds and Feeds, CNC Programming, Additive Manufacturing, Exotic Materials, etc.—I sat in on a group discussion among operators, engineers and programmers as they worked from a blueprint to identify the optimal machines, tooling and processes for manufacturing the part in question. Three of the sessions were structured in this way.
Each team, generally consisting of five to six members, discussed the plan and the related part to begin developing a machining approach. Everything from part geometry, to material, to machining methods and tooling were examined, including deburring and surface finishing.
It was fascinating to observe the thought process behind deciding how you get from a hunk of metal to a detailed, often geometrically complex finished part with the lowest cycle times, the fewest setups, and a process where each step logically leads to the next. I’ve sat down with individual shop owners (see this article from a recent issue) as they’ve explained the logic behind their decisions, but to witness a group discussion in which everyone discussed their personal experiences—both victories and failures—and the tricks they’ve learned along the way for making deburring part of a machining step, or developing fixturing that made setups easier to accomplish gave me new respect for all the thought and planning that goes into machining parts from raw materials.
The audience was a mix of engineers, programmers and machine tool builders. Their different perspectives and experiences made for lively conversations.
At the conclusion of the discussion period, a representative of each table addressed the hall, describing the group’s machining path, including the reasoning behind the decisions they’d made. Once their presentations had been made a member of the company that provided the part and print—in this case, Don Corwin of Buell Automatics—revealed the backstory, including the part’s history, intended usage, and current manufacturing status.
The vast majority of mass finishing processes I’ve encountered in shops use a large vibratory tumbler inside of which a mishmash of workpieces and finishing media swirl around in contact with one another, serving to smooth, deburr, radius or polish the workpieces.
While this might be perfectly fine for some applications, what about parts that have complex shapes or delicate features that could become damaged if they were to bump into each other during such a frenetic finishing process? For these, an alternate method of introducing parts to finishing media might be required to prevent potential damage from occurring.
In fact, Rösler Metal Finishing suggests three automated options to completely finish workpieces such as these or to perform targeted finishing of specific surfaces in a high-production environment, leveraging the advantages of robotic handling.
The first is shown above. Called Surf Finisher, it uses one or two robots with custom grippers to pick workpieces from a conveyor, immerse them into a rotating work bowl filled with the appropriate grinding or polishing media, then return them to an outbound conveyor. The work bowl is available in different sizes to enable the finishing of a single, large parts or the simultaneous finishing of multiple smaller parts. The robot can guide the workpieces through the processing media in pre-programmed movements including defined treatment angles, different immersion depths and rotary motion to enable the targeted finishing of specific surface areas.
The work bowl with processing media is also rotating at a speed of up to 80 rpm (actual speed is determined by the types of workpieces and finish requirements). The robotic movement combined with the work bowl rotation creates a “surfing” effect with very high pressure between workpiece and media. This concurrent, intensive pressure is said to create a surface smoothing effect in a relatively short amount of time, achieving Ra finishes to 0.04 micron.
The second, shown above, also uses one or more robots that perform two functions: material handling and programmed movement of workpieces through the processing media. For this system, which is called High-Frequency-Finisher (HFF), the media for wet or dry processing within the work bowl are agitated by vibration with a speed as high as 3,000 rpm. The robot with custom gripper immerses the workpieces into the agitated media, and the dual movement of the robot and media results in a high-pressure, highly intensive treatment of the parts completed in fast cycle times.
The third, shown above, is a new version of Rösler’s Drag Finishing system that includes automatic workpiece loading/unloading. In fact, this automated system was developed for Walter AG, multinational cutting tool manufacturer, to enable the company to automatically deburr a variety of different sized tool bodies instead of having its employees do that manually.
The system uses two interlinked drag finishing machines each having six working spindles served by a robot that automatically installs and removes tool bodies in and out of the spindles. The finishing process for these tools requires a safety load system that combines workpiece surface modeling and load pattern simulation. To ensure that handling errors do not occur, electronic sensors continuously monitor the pneumatic coupling system to ensure tool bodies remain safely fixtured in the spindles.
Once loaded, the tool bodies are then “dragged” through the stationary wet or dry processing media. Process parameters such as carousel and spindle speeds, immersion depth and treatment times are stored in pre-set programs in the system’s PLC. After completion of the finishing cycle, the robot removes the tool bodies, moves them to a rinse and cleaning station, and then places them onto a tray.
The company says this system can also be used to perform effective, repeatable surface finishing for items such as orthopedic implants, geared components, and aerospace and automotive components.