Failures of steel parts in service or production occur very infrequently. However, when steel parts fail, the consequences are dire. Quench crack- this is not good! Here are 7 ways that steel can fail as a result of Quench Cracking from heat treatment.
Overheatingduring the austenitizing portion of the heat treatment cycle can coarsen normally fine grained steels. coarse grained steels increase hardening depth and are more prone to quench cracking than fine grain steels. Avoid over heating and overly long dwell times while austenitizing.
Improper quenchant. Yes, water, brine, or caustic will get the steel “harder.” If the steel is an oil hardening steel, the use of these overly aggressive quenchants will lead to cracking.
Improper selection of steel for the process.
Too much time between the quenching and the tempering of the heat treated parts. A common misconception is that quench cracks can occur only while the piece is being quenched. This is not true. If the work is not tempered right away, quench cracks can (and will) occur.
Improper design– Sharp changes of section, lack of radii, holes, sharp keyways, unbalanced sectional mass, and other stress risers.
Improper entry of the part/ delivery of the quenchant to the part. Differences in cooling rates can be created, for example, if parts are massed together in a basket resulting in the parts along the edges cooling faster than those in the mass in the center. Part geometry can also interfere with quenchant delivery and effectiveness, especially on induction lines.
Failure to take sufficient stock removal from the original part during machining. This can leave remnants of seams or other surface imperfections which can act as a nucleation site for a quench crack.
Finally, materials that are heat treated to very high strength levels, even though they did not quench crack, may contain localized concentrations of high residual stresses. If these stresses are acting in the same direction as the load applied in service, an instantaneous failure can occur. This will be virtually indistinguishable from a quench crack during an examination, due to its brittle failure mode, lack of decarburization on surface of the fracture, or other forensic evidence of a process failure. When looking at quench cracking failures under the microscope, cracks and crack tributaries that follow the prior austenitic grain boundaries are a pretty good clue that grain coarsening and or its causes- overheating or too long time at temperature- occurred. Temper scale on the fracture surface helps the metallurgist know that the crack was present before tempering. Decarburization may show that the crack was open prior to quenching. Photo1 Thanks to WIP SAMI over at British Blades for the photo.
Our metal manufacturing shops are among the types of facilities eligible for the proposed one year extension.
EPA is currently proposing to:
Extend the date by which the owners or operators of certain facilities must prepare or amend and implement an SPCC plan by one year to November 10, 2011; EPA HQ: 16,617,179 gallons of water used annually here.
Delay the compliance date for facilities with milk containers that are constructed according to the current applicable 3-A sanitary standards:
Maintain the current November 10, 2010 compliance date for drilling, production and workover facilities that are offshore or that have an offshore component, and for onshore facilities required to have and submit FRPs;
Reconcile the proposed compliance dates for new production facilities.
The proposed amendments do not remove the regulatory requirement for owners or operators of facilities in operation before August 16, 2002 (other than facilities with milk containers described above), to maintain and continue implementing an SPCC plan in accordance with the SPCC regulations then in effect. Our metal manufacturing shops are among the types of facilities eligible for the proposed one year extension. EPA is seeking comment on whether a shorter extension period (6 to 9 months) is warranted for facilities rather than the proposed one year extension. In considering a shorter compliance extension period, we request comments on the criteria to consider, such as discharge history, size and type of facility, potential risk posed, and ability to come into compliance. If you think that you will need more than 6 to 9 months to get your plan done and signed by a Professional Engineer,we suggest that perhaps you might want to share your comment to that effect with EPA.
To comment on the proposed amendments, go to http://www.regulations.gov. Follow the online instructions to comment on Docket ID No. EPA-HQ-OPA-2009-0880. Any alternative dates presented must include appropriate rationale and supporting data for the Agency to be able to consider them for final action.
The public has the opportunity to comment on the proposed rule during a 15-day period following its publication in the Federal Register. Clock starts ticking today. More information on the proposed rule: Proposed dates pdf : Text of proposed amendments: (Please note: This is a prepublication version, this is scheduled to be published in the Federal Register today.)
"I have to get it right too?"
You wouldn’t use a gage that measures in 0.001″ increments for a requirement in 0.0001.” Why tolerate similar inaccuracies in your OSHA reporting work product?
Guest Post by James Pryor II, American Safety and Health Management Consultants, Inc. Here are 5 tips to help keep your OSHA 300 up to requirements:
Record ALL hours worked by ALL employeescovered by the records – Hourly , Salary, Part Time, and Temporary.
If necessary,estimate by multiplying the average number of workers by 2000 to obtain hours worked.
Verify hoursby confirming against what amount was paid to unemployment insurance.
If the hours you report are too low (underestimated) the incidence rate will be too high.
If the hours you report are too high (overestimated) the incidence rate will be too low.
Why is the incidence rate so important? It is the go / no go gage that will determine whether or not your shop safety program gets a pass or a closer look. The DayAway and Restricted Time Report is a listing that is closely examined by OSHA. Too high an Incidence Rate will indicate a need for a review. Too low an incidence rate could give a false picture of your safety performance and lead to unintended consequences.
We don’t really have the technology to do a long form Gage R&R on your safety paperwork, but following these 5 tips will assure that your program “meets print.” Use your passion for quality to assure high performance in all aspects of your shop’s safety program.The actionable information in your accurate OSHA 300 Log will help you continue to improve your shop’s safety performance.
Here is a link to our post on the 7 Indirect Costs of a Failed Safety Program.
Photo credit: Thanks Eighth Diary. Good luck with your work in the office!
Thanking the Buffalo Business First for their authoritative study on manufacturing jobs lost in the top 100 markets here in the U.S. over the past decade.
Using latest Bureau of Labor Statistics figures, G. Scott Thomas documented 10,114,400 manufacturing jobs in the top 100 markets in May 2000.
In May 2010, the number of manufacturing jobs in those same 100 markets had fallen to 6,641,900. That is a loss of 3,472,500 manufacturing jobs, a 34.33% decline. Lots of manufacturing people in this situation.
Surprisingly El Paso, Texas just edged out Detroit, Michigan for highest percentage of manufacturing jobs lost at -55.44%.
Detroit lost – 55.41 % or 221,200 jobs gone.
The most surprising fact in the study? Only 2 of the top 100 markets showed any growth in manufacturing jobs: Las Vegas,Nevada added 0.5% (100 jobs!) and Bakersfield, California added 16.36 % or about 1800 manufacturing jobs.
Only 4 markets’ manufacturing job losses were in the single digits. 98 out of 100 of the top U.S. markets posted declines in manufacturing jobs over the decade. What do you think that we can do to turn this around? What will you do to make a difference? Photocredit
Repost from Change the Perception: Today's manufacturing jobs are high skill-high thinking!
Often times when you read the headlines about manufacturing job loss, the type of job is not defined. The term manufacturing is very far reaching, it really has come to include anyone that is part of creating anything material. When you read a headline that says “5,000 Manufacturing Jobs Heading for Mexico”, chances are they’re not referring to what would be called “high-skill, high-education/training” type jobs.
This is an important point to understand. We’ve drawn attention to the skilled-labor shortage in the U.S. a number of times here on CTP, because it’s a fact. It’s happening currently and it will continue to get worse…but don’t get confused, the typical manufacturing jobs in the U.S. are no longer going to the production style jobs. Manufacturing jobs in the U.S. continue to evolve into high-skill, thinking type jobs. This article illustrates the requirements needed to be competitive in today’s manufacturing job market. Manufacturing is rich with opportunity for those that know how to learn, and have a mindset of continuous-learning. Now is a great time to direct young people into manufacturing, but set them on a path of education first!
Thanks again to Ryan at Change the Perception for championing the cause of skilled manufacturing here in the US. Photo credit
Some things you want to have bubbles, some you don’t. Usually, Bubbles are good.
In beermaking, yeast consumes the sugars in the wort and convert them into CO2 gas bubbles- carbonation.
In steel making the main reaction is the combination of Carbon in the melt with Oxygen to form a gas. At the high temperatures involved, this gas is very soluble in the molten bath.
If the Oxygen that is available for this chemical reaction isn’t completely removed before the steel is cast the gases will continue to be forced out of the melt during solidification, resulting in porosity in the steel. Bubbles and where the gas goes can be important in your steel part.
In order to control the evolution of gas, chemicals called deoxidizers are added to the steel. These chemicals, Silicon or Aluminum, Vanadium, Columbium, Niobium scavenge the available oxygen in the molten steel, react chemically to form solid oxide particles dispersed throughout the steel, rather than bubbles of Carbon Dioxide.
The amount and type of deoxidizer added determines the type of steel. If sufficent deoxidizers are added, no gas is evolved from the solidifying steel, and the steel is said to be “killed.” The ingot drawing labelled number 1 shows a fully killed (deoxidized) steel showing only a shrinkage cavity, and no bubbles or porosity. ( This shrinkage cavity would be cropped off in normal rolling practice.) Because gas is still evolving, this beer is NOT KILLED.
Killed steel has more uniform chemical composition and properties than rimmed, semi-killed, or non-killed steels, and generally less segregation. The uniformity of killed steel and and its freedom from porosity makes these steels more suitable for critical components and for applications involving heat treatment.
Killed steels generally contain 0.15-.35 weight percent Silicon as a deoxidizer, and may contain some of the other elements as mentioned above. These other elements may be used as deoxidizers or as grain refiners. Steel grades with a Carbon maximum of 0.30 weight % and above, and all alloy steels are typically provided as “killed steels.” Free machining steels such as 12L14, 1215, and some 11XX series steels are not “killed” with Silicon, Aluminum, etc., due to their deleterious effects on tool life and machinability. The high amounts of Manganese in these steels form Manganese Sulfides to promote machinability, and also the Manganese scavenges excess Oxygen, preventing evolution of CO2. Killed steel is specified so your critical parts won't have bubbles in them. Killed steel- for critical parts. Non-killed beer for critical after work down time.
Cheers! Beer Bubbles Photo Credit
Ingot scan from a handout in my files originally after Making Shaping and Treating of Steel. Beer Head Photo Credit Bread with Holes
w00t! w00t! 1st place solar car and PMPA shop part of it!
PMPA member Wolverine Machine Products Company in Holly, Michigan knows a little bit about Precision Machining.
With their new Wardjet waterjet cutting table, they had exactly the capability that the University of Michigan Solar Car Race team needed. A new view of Precision Machining.
They used their new waterjet capability to fabricate fixtures to help the U of M team lay-up the carbon fiber parts.
They used more traditional precision machining technologies to help the team make parts out of aluminum for wheels, suspensions, and other important systems.
Blaine Walker, Wolverine Machine’s Special Projects Manager had this to say about their role in the U of M project, “Working with the University of Michigan students gave us a great opportunity to explain tolerances, stackups and other critical pieces of manufacturing knowledge. That they came in first place is a sign that they were listening.”
And Blaine, that first place finish also tells me that Wolverine Machine makes quality parts!
Here’s one other lesson for the precision machining industry: The waterjet parts were cut out of plate material. The rest of the precision machined parts were aluminum. Lightness and strength were critical in this solar car’s performance, and automotive jobs in the future will likely be non-traditional materials compared to todays specifications.
What do precision machining, Wolverine Machine, and Solar Cars have in common? All three of these are pointing the way to a brighter future for high skill high technology manufacturing right here at home.
Thanks for taking on the special project, Wolverine. And congratulations to the University of Michigan Solar Car Race team! Congratulations! University of Michigan Solar Car Team
Was held up the other day while the authorities cleaned up a bit of a mess. Fortunately, it wasn’t my mess. What is so important that you have to text it while driving?
Delaware has become the 30th state to ban cell phone use while driving.
30 states now ban cell phone use while driving.
What about your state?
What about your community? What about your company? Do you have a policy regarding distracted driving? Should you?
30 state legislatures and governors seem to think so. Here’s a list. Unconvinced?
Still need a compelling business reason?
How about occupational fatality statistics for sales and managerial workers?
I’ll always take your call, but if I’m driving, it will go into voice mail.
The Severe Violator Enforcement Program (SVEP) directive became effective on June 18. "Do as I say, not as I do?" (You wouldn’t know it from the OSHA website, they didn’t provide either a date or directive number on their “directive.” But negligence on their part on paperwork isn’t the crime that it is when employers make a paperwork omission…)
According to the unnumbered, undatedDirective posted on the website,“This new directive establishes procedures and enforcement actions, including mandatory follow-up inspections and inspections of other worksites of the same company where similar hazards or deficiencies may be present. It replaces OSHA’s Enhanced Enforcement Program (EEP).”
“This Instruction establishes enforcement policies and procedures for OSHA’s Severe Violator Enforcement Program (SVEP), which concentrates resources on inspecting employers who have demonstrated indifference to their OSH Act obligations by committing willful, repeated, or failure-to-abate violations. Enforcement actions for severe violator cases include mandatory follow-up inspections, increased company/corporate awareness of OSHA enforcement, corporate-wide agreements, where appropriate, enhanced settlement provisions, and federal court enforcement under Section 11(b) of the OSH Act.”
What can trigger SVEP Status?
Willful, repeated or failure-to-abate violations in one or more of the following circumstances:
• A fatality or catastrophe situation
• Industry operations or processes that expose workers to severe occupational hazards
• Workers exposed to hazards related to the potential releases of highly hazardous chemicals
• Egregious enforcement actions For our industry, Falls (General Industry) and Amputations appear to be the primary categories for awareness.
Here are the appropriate references for Fall Hazards, General Industry: 29 CFR §1910.23 – Guarding floor and wall openings and holes [Walking-Working Surfaces] 29 CFR §1910.28 – Safety requirements for scaffolding [Walking- Working Surfaces] 29 CFR §1910.29 – Manually propelled mobile ladder stands and scaffolds (towers) [Walking-Working Surfaces] 29 CFR §1910.66 – Powered platforms for building maintenance [Powered Platforms, Manlifts, and Vehicle-Mounted Work Platforms] 29 CFR §1910.67 – Vehicle-mounted elevating and rotating work platforms [Powered Platforms, Manlifts, and Vehicle-Mounted Work Platforms] 29 CFR §1910.68 – Manlifts [Powered Platforms, Manlifts, and Vehicle-Mounted Work Platforms]
For Amputations Information see this link: Amputations And don’t expect any slack for paperwork omissions, like say, omitting a directive control number or date on a record…
This year I am going to celebrate Independence day as Interdependence Day. I am going to let my US side and my Canadian sides work together. I invite you to join me, independently interdependent.
I just love Independence Day and its northern cousin, Canada Day. Actually, I remember Canada Day as Dominion Day, but that just proves I’m an old fogie with Canadian roots. PMPA- North American means US and CANADA.
Independence Day is a US federal holiday commemorating our Declaration of Independence from the Kingdom of Great Britain in 1776. While most of us celebrate this holiday with patriotic displays, fireworks, cookouts, and much nationalistic fervor, I see this holiday as celebrating the triumph and coming of age of reason and representative government vs. the old myth of divine right of kings and blind obedience. To me Independence Day is as much about the wisdom and intellectual achievement of our founding fathers as it is about nationalistic pride. My father would say “Son, you think too much.” He would probably be right, but hey, he kept me well stocked in books and allowed me all the freedom to read that a kid could have. Thanks Dad.
Unlike the US Independence Day holiday which recognizes separation, the Dominion Day Canada Day holiday recognizes the “uniting” of the 4 British North American colonies and the province of Canada (which ended up split into two provinces, Ontario and Quebec) into a new Kingdom- Canada, within the British Empire. This happened on July 1, 1867 according to the history books. I was never able to understand that particular arrangement, as the King of Canada would have been the King of England. “How can the king of one country be the king of another country, and both be independent?” My Canadian mother never got it through my thoroughly US cranium, though she tried. But then again, I was an intellectually unruly child…
But the idea of the American side of my family celebrating independence and the Canadian side celebrating continued interdependence gives me the real subject for today’s blog: Interdependence day This year I am going to celebrate Independence Day as Interdependence Day. I am going to let my US side and my Canadian sides work together. I invite you to join me, independently interdependent. Here are four hallmarks of our independent interdependence:
Citizenship
Stewardship
Diversity and Coexistence
Sustainable Improvement
Citizenship Citizenship to me is a code word for personal responsibility. To not do things against my own interest. Or against the interest of my “neighbors.” As individuals first, but also collectively. Citizenship includes loyalty to the principles of our Constitution, and obedience to lawful authority; But to me it is far more than that. Citizenship is a way of living in the world. Citizens are part of the solution process, not the problem. Citizenship problem. Under my definition, BP right now has a “Citizenship Problem.” Stewardship
Part of that “Citizenship thing” is recognizing that our actions and decisions affect others, and so we need to behave responsibly. Our shops use lean manufacturing processes to eliminate waste and so to not dissipate valuable resources that will be needed by others in the future. Our shops are good stewards of the resources we have. While the press paints businessmen as stingy and greedy, the fact is that our drive to eliminate waste is to be good stewards of what we have, not just to reduce costs. We have capital, employees, customers, and intellectual means of production that enable us, our families, our employees and their families, and our communities to thrive. Recognizing this interdependence helps us realize that all of us can lead efforts for stewardship for a better shop, home, community, state, province, country, and world.
We’ll reserve comment on this aspect regarding BP… Diversity and Coexistence
My office is different than your office. Your house is different than mine. Your shop is different from hers. Her business model is different from his.
PMPA’s North American Trade Association model demonstrates how all of us, despite the fact that we compete, can also profit by sharing and approaching our markets and processes differently. By behaving as neighbors, professionals with a common mission, to make the parts that make today’s technologies serve all of us with improved safety, quality, convenience and quality of life. Viva la difference! It is not enough for us to tolerate differences, We need to embrace them. It is the richness of approaches that assures that all opportunities for profit (and service!) out of a given market or resource are achieved. ‘One size fits all’ never fits anybody real well. If you don’t like diversity, or differences, well, then have you considered opening a shop in say, North Korea? Sustainable Improvement
When I was growing up, the word “Progress” was as widely used as the word “Green” is today. I like “Progress” better. Progress was generally used to mean growth. Improvement. Better. I am a big fan of continuous improvement. I have an internal principle that asks “is it better because of what I did?” I want my kids to do better than I did. I want this years’ business to be better than last years’.
But what we didn’t ask back in the day when “Progress” was as worshipfully served as “Green” seems to be today was, “What is the cost?And how do we measure progress?” “Better for me,” at the cost of “worse for you” is no bargain. So I ask if the improvement is sustainable, a genuine improvement? Or is it not sustainable? You know, like a Bernie Madoff Investment Fund Business Model? Sustainable improvement brings us back to Citizenship and Stewardship. Embracing Diversity- Coexistence helps us measure the impact of our improvements on all of us who might be impacted. Recognizing that we’re all impacted drives us to wanting to make improvements. Final thought Independence? Yes, I value that as giving me the agency to make the right decisions. Interdependence? Yes, for you and I, and approximately 6.7 billion other folks; 307 million of whom celebrate Independence Day, 33 million of whom celebrate Dominion Day Canada Day, we are also interdependent. That is why Citizenship/Stewardship (Quality, Professionalism, Fair Dealings, Service to others, and Mastery of our Craft) is so important. Happy Independence Day. Happy Interdependence Day. May your dedication remain focused on Citizenship, Stewardship, Diversity and Coexistence, and Sustainable Improvement. No matter on which side of the border you live or make parts. Ultimately, we’re all customers. I’ll do my best. How about you? Happy Interdependence / Independence Day! Photo credit Cute Flag Wavers
