You might think that you know what you’re asking for, but when talking with your supplier, it’s important that you both use the same language to be sure you’ll get what you need.
See my article on the meanings of terms used in the sheet metals industry in the February 2018 issue of @Metalforming from @PMAtalk http://www.metalformingmagazine.com/magazine/article/?/2018/2/1/Know_Your_Sheetmetal_Terminology–Part_1
Not getting what you need from your 1008/1010 #steel? Read about the limitations of ordering AISI 1008/1010, and why you might need to change to something like SAE J2329 for more consistent performance – March 2018 issue of @Metalforming from @PMAtalk
http://www.metalformingmagazine.com/magazine/article/?/2018/3/1/Know_Your_Sheetmetal_Terminology–Part_2
I’m now writing the monthly Science of Forming article for Metalforming Magazine – it’s a great honor to be taking over from Dr. Stuart Keeler.
See my first article, The More You Know, on page 36 at http://metalformingmagazine.com/magazine/digital-issue/?/2017/Dec
This sounds like ancient history. But is it?” …
Danny Schaeffler
Engineering Quality Solutions, Inc. 4M Partners, LLC
http://www.EQSgroup.com http://www.Learning4M.com
The type and depth of knowledge required to form sheet metal changed along with the industry. Experience is no longer the only measure of an employee’s capabilities. During the past 25 years, thousands of new grades of steel were introduced, aluminum components became more common, forming technologies evolved, and computer analysis began to supplement traditional processes. Gone are the days of only forming a handful of steel grades and employing expensive trial-and-error approaches to confirm manufacturability. Today’s metal forming professional needs to understand data analysis, sheet metal mechanical properties, chemistry, and effective communication to be successful.
The business of forming sheet metal changed dramatically over the past few decades. Metal formers once formed only a handful of sheet metal grades – mostly mild steel. The technologies of forming were powerful, but fairly basic. We tested dies and designs by iteratively forming metal until we were comfortable that the die design and component geometry could work reliably on the plant floor. Your best tools to maintain a productive workforce were employee experience and transfer of experience to apprentices.
During the late 20th century, increased automation, computing tools, and a large variety of metals to choose from changed the knowledge requirements and technologies of manufacturing. The sheet metal forming industry, while a bit late at adopting new technologies, saw significant changes over the past 25 years. Alternative forming technologies, such as hydroforming and servo presses, are becoming more common.
Product manufacturers today require greater strength from components while reducing their mass. These requirements are intended to improve energy efficiency, automotive occupant safety, and product reliability. As a result, steel suppliers now offer thousands of product grades. OEMs are also migrating some components to aluminum.
Die tryout is supplemented by virtual simulation. All of these changes require managers to reassess how they hire and train their workforce. New hires should come in with a solid general education, including math skills, communication competence, and competence in information technologies.
New materials each come with their own properites and variability. Only the collection and analysis of property data can give us an increasingly accurate picture of the potential range of mechanical properties for a given grade. Then we can determine the appropriateness of that grade for our purposes and adjust our design and manufacturing activities to better use the properties.
Today’s metal forming organization must meet a number of workforce demands to keep pace with industry changes and continuously provide quality components. New hires should be competent with computing, have a solid foundation in mathematics, and be adaptable to change. Older employees often need to learn new skills and adapt to changes, themselves.
Since the 1970s, computing and automation has been a dominant force in manufacturing. Just as different skills were needed when industrial manufacturing replaced artisan shops during the late 19th and early 20th centuries, today’s manufacturing operation requires a very different set of skills than the plants of the mid 20th century.
Generally, employee capability is based on two things, technology-specific experience and general knowledge. Technology-specific experience includes the specialized job skills learned to support production. General knowledge includes the topics we learned in school. Among the most important general knowledge skills are literacy and numeracy.
Today’s science and math-based manufacturing environment requires employees have a solid educational foundation. Employees must be able to learn how to understand the the measure of sheet metal properties, operate automated equipment, understand diagnostic measurements, interpret information, and be able to articulate issues, opinions, and solutions. Employers must be confident that new hires have sufficient general knowledge to learn the science and technology of modern forming. Solid general knowledge also offers the employer a greater probability that employees will be able to adapt to changes in forming and material technologies.
Technology-specific experience is a continuing activity requiring employees to remain competent in their own profession. Employees must also remain aware of related technologies, material properties, innovations, and processes that impact their activities. Employers should develop employee training programs to maintain a sufficient and effective skill level for each employee.
4M teaches professionals about the fundamentals along with the latest advances in sheet metal forming. We can help you design a training program to meet your needs both to resolve current issues and to plan for your forming future.
You can schedule training at our Metro Detroit facility or at your site.
Our website: www.learning4m.com
Phone: 1.612.STRAIN1
Tim Worstall, a contributor to Forbes magazine, recently wrote an opinion piece, “It’s Not China Or Trade That Killed The Steel Jobs But Recycling.“
The crux of the piece was that the job losses in the steel industry over the past half-century can be attributed to the rise of more efficient minimills capturing business that was once held by integrated mills.
I think this is an oversimplification of the issues and market dynamics at play. My posted response follows…
I think you are glossing over some important considerations.
Most of the job losses you cite came in the early to mid-80’s when a vast number of obsolete integrated mills shuttered. Yes, there were an increasing number of minimills built, but except for a few cases, the capacity of each one was 10-100 times smaller than the number of tons that could be produced out of an integrated mill.
It might be more useful to concentrate on the changes of the last 2 decades. 20 years ago, there were names such as Bethlehem, National, Rouge, Inland, and LTV Steel (where I used to work), with only US Steel larger than them. USS absorbed National, and what became the world’s largest steelmaker for a time, ArcelorMittal, took over Bethlehem, National, Inland, and LTV (among others). In all cases, there were tremendous job losses as “redundancies” were eliminated. However, the only losses were in people – very little capacity was permanently removed from the market. This led to improvements in “man-hours per ton,” as did more efficient processes and practices.
Concurrent with this, the now-larger companies had fewer competitors (since they bought them) and as such were able to exercise greater pricing discipline, transitioning from chasing more tons that would lower fixed costs to going after more profitable tons associated with a greater percentage of value-added products like those used by auto and appliance OEMs. In the past, with 10 potential competitors, getting significant tons from the largest customers usually meant lowering the price to critical levels. With only one or two competitors, other factors became important to OEMs, like ensuring they were able to purchase enough tons of the advanced grades to satisfy their auto/appliance production levels. Up until the past few years, the advanced grades were essentially the domain of the integrated steelmakers.
These advanced grades, either from a high strength/high formability perspective or from a surface quality perspective, are difficult to purchase from overseas steel companies in a cost-effective manner where just-in-time delivery is critical. So this business is not being lost by domestic steel makers. What is at risk is the lower end – the high-volume lower-cost products that do lower mill fixed costs. You don’t need great strength or a perfect surface to make the rebar product you cite in the article. Steelmakers around the world have the ability to make these grades, so any governmental actions to artificially adjust cost of production or sales price can distort free-market balances.
Finally, most integrated mills add around 25% scrap charge to all their melts, and minimills are investing in new technologies that will allow them to reduce the amount of scrap they need to use in their product. This will allow them to improve ductility and surface, and reduce their exposure to the international scrap market fluctuations.
Danny Schaeffler
Engineering Quality Solutions, Inc. 4M Partners, LLC
http://www.EQSgroup.com http://www.Learning4M.com
One of the challenges with direct hot forming a galvanized PHS is the risk of microcracks in the coating and an associated restricted process window. Steel company voestalpine has with their phs-ultraform® product developed a process that they have termed phs-directform®. The process steps are similar to conventional direct hot forming with one significant difference – the use of a non-contact “pre-cooler” which cools the heated blanks to around 640°C before press hardening. Using this approach produces a product that offers cathodic and barrier corrosion protection, rather than just barrier corrosion protect provided by the alternative Al-Si coating.
Danny Schaeffler
Engineering Quality Solutions, Inc. … http://www.EQSgroup.com
4M Partners, LLC … http://www.Learning4M.com
Nissan just announced the expanded use of an Advanced High Strength Steel (AHSS) that has a tensile strength of 1.2GPa (= 1,200MPa = 175 ksi = 175,000 psi). This follows their initial announcement in October 2011.
Things we’ve learned:
This is a great technical achievement, but a bigger hurdle may have been in the collaborative alloy development approach: two steel competitors partnered with one of their customers.
How will this play out? Will the steel companies be allowed to supply the grade to other automakers? Will the steel companies be allowed to market the grade through their partners? Nippon has Joint Ventures with ArcelorMittal in the USA and Ternium in Mexico; Kobe has Joint Ventures with US Steel.
http://www.nissan-global.com/EN/NEWS/2013/_STORY/130312-01-e.html
Danny Schaeffler
Engineering Quality Solutions, Inc. … http://www.EQSgroup.com
4M Partners, LLC … http://www.Learning4M.com
We all hear frequent discussion about Advanced High Strength Steels, increased use of aluminum, and carbon fibres. Much of the discussion in automotive focuses on materials and processes to increase product strength and reduce mass. A pamphlet published by Volvo Construction Equipment (http://tinyurl.com/d3c3cvh) discusses the increasing role industrial design plays in new product development. Are we looking far enough forward in product design to anticipate the additional forming challenges we will face in producing new geometries?
A product’s aesthetic design is increasingly important across many manufacturing industries. Shape and color affect customer perceptions of quality, functionality, and style, along with the product’s maintainability and durability. As we develop new materials, tooling, and processes to meet our more “technical” specifications, we must also look forward to how our products will look in the future. These issues extend beyond automotive. Who would have guessed 15 years ago that the old beige washer/dryer in your laundry room would become a stylish showpiece item in a modern laundry room? Or that your computer would also become an item of style, merged with your phone, and held in your pants pocket?
Food for thought …
Honda has developed a production manufacturing process that lets them join steel to aluminum skin panels. The first application of this will be on the 2014 Acura RLX, which will have an aluminum door skin joined to a steel door inner. This technique is projected to reduce the weight of the doors by 17%, and improve ride stability by concentrating the weight closer to the vehicle center. This application is a result of three key breakthroughs: development of a 3D Lock Seam structure where the aluminum outer is hemmed twice, development of a process so the adhesive completely fills the gap between the panels, and development of a technique to account for the different thermal characteristics between steel and aluminum.
http://world.honda.com/news/2013/4130218New-Technology-Join-Steel-Aluminum/index.html
Danny Schaeffler
Engineering Quality Solutions, Inc. … http://www.EQSgroup.com
4M Partners, LLC … http://www.Learning4M.com
Through my website, someone asked about the deformation modes in sheet metal forming. My response:
The three deformation modes in three-dimensional forming are draw, plane strain, and stretch. These can be visualized by imagining a circle of known diameter etched into the sheet metal when it is still a flat blank. Deforming the blank turns the circle into an ellipse. By definition, the longest dimension of the ellipse is the major axis, and you can determine the major strain as the percent increase in that dimension. The minor axis is perpendicular to the major axis.
Depending on the shape of your blank and your tools, the dimensions of the minor axis can either be smaller than the original diameter, the same size as the original diameter, or larger than the original diameter.
→ If the dimension of the minor axis is smaller than your original circle diameter, you will have negative minor strain, and you are in the “draw” deformation mode.
→ If the dimension of the minor axis is the same as your original circle diameter, you will have zero minor strain, and you are in the “plane strain” deformation mode.
→ If the dimension of the minor axis is larger than your original circle diameter, you will have positive minor strain, and you are in the “stretch” deformation mode.
These three zones are represented on the Forming Limit Curve from left to right as the downward sloping section (draw), the lowest point on the Curve (plane strain, at 0% minor strain), and the upward sloping section (stretch) to the right of the lowest point.
Knowing your deformation mode in a given area will help with troubleshooting any issues related to local metal flow.
Best of luck!
Danny Schaeffler
Engineering Quality Solutions, Inc. … http://www.EQSgroup.com
4M Partners, LLC … http://www.Learning4M.com
dannyeqs
Bill Frahm