As more applications and newer technology move toward non-leaded steel applications, I thought that a brief refresher about lead and its role in shops might be timely.
The 0.15- 0.35 weight percent of lead contained in these bars helps them machine 25 percent faster with less power required.
Leaded steel bars historically have been a mainstay raw material in the screw machining industry. As more applications and newer technology move toward non-leaded steel applications, I thought that a brief refresher about lead and its role in shops might be timely.
Leaded steel bars are standard steels and widely available. In the U.S. 12L14 is the predominant grade. 11SMnPb30, 11SMnPb28, 9SMnpb28, and 9SMnPb36 are German designations nominally equivalent to 12L14. The Chinese version of 12L14 is Y15Pb; Japanese nominal equivalents include SUM22L, SUM23L and SUM24L.
Leaded steels are selected for use for the savings achieved in producing parts by machining.
Leaded steels are not appropriate for all parts, and parts with low amounts of stock removal may not create any noticeable savings.
Today’s leaded steels are more consistent, more uniform, than they were when produced by the ingot process.
The decision to use leaded steels for a specific part must be based on the economics for that part—volume, stock removal, part complexity, tolerances required, surface finish needed are all factors that contribute to that economic calculation.
There is no sacrifice in mechanical properties when adding lead to steel. Neither longitudinal nor transvers mechanical properties are affected by the addition of lead to steel.
Leaded steels are currently permitted under European Union regulations covering End of Life Vehicles, RoHS.
The reduction in energy required and time needed (about 25 percent!) to machine a part make leaded steels environmentally friendly by reducing carbon dioxide emissions to create parts compared with using unleaded materials.
In order to be dangerous to humans, lead must be in a soluble form. The lead in steel bars is a separate solid phase. IARC lists lead under its Group 2B category, “possibly carcinogenic to humans.”
Lead, as well as chromium, copper, manganese, nickel, and phosphorous is required to be reported under Sara 313 (40 CFR 372.65) when they are above established thresholds.
Starting on Thursday August 8, 2024, PM will begin “gating” its premium content, asking all new website users to provide some information about themselves — name, title, employer, email address — before they are provided free access to the content.
We are doing this because the ways PM’s audience finds and accesses our content is changing. Google’s search algorithms, increasingly, make it difficult to connect PM’s content with the people who might make use of it. On top of that, generative AI like ChatGPT is serving up PM content to internet users without attributing that content to PM.
As a result, it has become increasingly important for PM evolve its audience development strategy and learn as much as possible about who is accessing our content, what content they are accessing and how they are accessing it.
With this audience development strategy, we hope to do two things:
First, we will be better able to deliver directly to our audience the editorial content that aligns with the machining materials, processes and technologies that interest them.
Second, we will be better able to connect the materials, equipment and services our advertisers supply with the audience that is most interested in them.
PM plays a distinctive role and has earned a place of esteem within the focused and specialized industry it serves. Large developments in the media landscape are forcing us to change the way we communicate with our audience. We are confident that our audience values the role PM plays in their professional lives and will join us in this effort to stay connected to them.
We thank you for your continued interest in and support of PM and welcome any questions you might have about the brand’s new content gating strategy.
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