The link in this post will take you to a table of the Top 10 Training Citations by OSHA for the Precision Machining Industry.
James Pryor II, Vice President with American Safety and Health Management Consultants Inc. (Ash,Inc.) has reviewed the latest available OSHA citations information and compiled this list of the Top 10 Most Cited Training Violations for the precision machining industry.
This listing also includes the OSHAweb link to information regarding each area , and training frequency and record retention information.
This is an example of a “Tool You Can Use” from PMPA to help you keep your shop compliant, competitive, and citation free.
While this application is medical, not metallurgical, the technology is worth a few seconds of your time…
Being a techie, I am always delighted by new technologies. So imagine when I found out about a $1.50 lensless microscope being demonstrated at Caltech. As we implement new technologies in our shops we eliminate waste and become both more capable and more efficient. This Caltech developed microfluidic microscope promises to improve efficiency, capability, and improve medical diagnostics in the third world where cost of detection is often a showstopper.
How do we currently diagnose diseases like malaria or cancer? A skilled technician examines blood samples brought to the lab using a conventional optical microscope. Laboratory, sample preservation, preparation, and transportation all add “loss” to the process.
With this Caltech device, a system of microscopic channels called microfluidics lead a sample across the light-sensing chip. Samples flow through the channel because of a tiny difference in pressure from one end of the chip to the other. The chip ‘snaps’ images in rapid succession as the sample passes across.
Cells tend to roll end over end as they pass through a microfluidic channel allowing the device create an image of the cell from every angle. This allows the technician to determine its volume and type by viewing the video made by the device. No lenses, no slides, no expensive transportation or sample prep, just in situ testing.
So what do we call this approach? How about ” Subpixel Resolving Opto-Fluidic Microscopy” or “SROFM.”
This $1.50 lendless laboratory, when coupled with the growing ubiquity of cellular phones around the world, could just make a difference in developing world medical diagnostics and outcomes. REAL quality of life benefits from technology.
Full story at MIT Technology Review We can see this type of application being developed for microtaggants on critical precision machined components for aerospace, medical or security applications where provenance and identity of the component are crucial to the mission…
Pure iron is barely harder and stronger than copper. Impurities are to iron, what paint is to an artist’s canvas.
Red Ochre is Iron
The problem with iron at this level of purity is that it is too soft and too ductile for most commercial uses.
This means that the iron products that we know and recognize are relatively and deliberately impure.
Iron also has three allotropes or crystal forms, delta iron (body centered cubic) gamma (face centered cubic) and alpha, body centered cubic. I was originally taught* that delta and alpha iron were the same allottrope, a distinction that now appears to be a chrming sign of old age… and the addition of impurities (alloying elements) have different solubilities based on these forms.
It is the addition of carbon and other elemental impurities which alter these allotropic forms that gives commercial iron and steel products their diverse properties.
When we look on the material certs that accompany our steel products , the first element that is reported is carbon. Carbon is ubiquitous, and has the dominant effect on the behavior of the iron based product to which it is part, even in the presence of large amounts of alloying elements.
What is implied by the certs is that after adding up all of the elements reported, the balance of the material is “iron.”
In 2009 world Iron and steel production was estimated to be 1,219.7 million metric tonnes.
Physics trivia: Iron is the heaviest atom that can be made by the fusion of stars. Iron is is the ‘ash’ of stellar nuclear fusion. Iron is abundant- the fifth most abundant element on earth, and sixth most abundant in the universe. Our blood is red because of iron, and since iron is an essential part of our bodies, we can truly claim that we are “Stardust.”
Iron is essential to almost all living things indeed it is key to the working of hemoglobin and oxygen transfer in humans, as well as in enzymes that are involved in the creation of DNA.
Our bodies store surplus iron in the liver, to cover for those days when we do not get our required 7 to 11 milligrams of daily iron.
When properly contaminated with carbon, manganese, a sprinkle of sulfur or phosphorous, iron makes some damn fine precision machined parts too!
*I was originally taught= Alloying Elements in Steel by Edgar C Bain and Harold W Paxton, 2nd edition:
“The metal iron, as shown in figure 1., exists in two isometric allotropic crystal forms: (1) alpha and delta iron, whose solid solutions are called ferrite (or delta ferrite) and (2) gamma iron whose solid solution is is austenite.” Cave painting Poster Lyrics by Jodi Mitchell, performed by Crosby, Stills, and Nash.
“A robot may not injure a human being or, through inaction, allow a human being to come to harm. “ – First Law of Robotics, Isaac Asimov
So what is going on here?
According to an Article in New Scientist, “in Slovenia a powerful robot has been hitting people over and over again in a bid to induce anything from mild to unbearable pain – in apparent defiance of the late sci-fi sage’s famed first law of robotics, which states that “a robot may not injure a human being“.
It’s all for a good cause, though, and one in keeping with Asimov’s First Law: “Even robots designed to Asimov’s laws can collide with people. We are trying to make sure that when they do, the collision is not too powerful,” Povše says. “We are taking the first steps to defining the limits of the speed and acceleration of robots, and the ideal size and shape of the tools they use, so they can safely interact with humans.”
“Determining the limits of pain during robot-human impacts this way will allow the design of robot motions that cannot exceed these limits,” says Sami Haddadin of DLR, the German Aerospace Centre in Wessling, who also works on human-robot safety. Such work is crucial, he says, if robots are ever to work closely with people.”
We’re OK with the idea of testing, but we’re not sure that volunteers’ perception of “pain” after say the first 12 or 13 hits is an objectively verifiable response variable.
But if its my arm, I’m not sure I’d like “stitches” or “bruise area” to be the measureable either… Full story.
“Competers are usually so caught up in meeting their day to day challenges that they can only worry about the future, while innovators see the present only as a stepping stone they can use to a biogger and better future.“- Daniel Burrus, Technotrends, Sept 2010, www.Burrus.com
Of course we have to do what we have to do right now. Now is where we live, Right?
I call this short term focus “the tyranny of the urgent.”
Must get truck loaded and shipped. Must get paperwork issued, must get…
When I look at companies that are growing and profitable, I find that they seem to have a different focus. They are the ones that are using a long term time focus.
Long term focus = profitable!
What is that different focus? LONG TERM THINKING
“Everywhere you look in this country, it seems that we are suffering from the consequences of too much short term thinking. Google doesn’t have this disease.” Paul Saffo, Discern Analytics, “The time is ripe for long term thinking, with memories still fresh of a financial meltdown- a byproduct of Wall Street’s demands for companies to deliver ever-higher profits every three months and meet earnings targets set by analysts.” – AP Article
So if we were playing Barbara Walters, and we asked you “If you were a time measuring device, what time measuring device would you be?”
Would you be a stop watch, or a calendar? And who on your team is the the other? After all, we will be living in Tomorrow, in just another day… Stopwatch 5 Year Calendar Gasp
Silicon plays many roles in steel but its most important is deoxidation; it is detrimental to tool life, machinability and surface quality in low carbon and free machining steels.
Silicon makes up about a quarter of the earths crust. It is mined as sand, quartz, mica, talc, feldspars, vermiculite, and others; silicon is a key ingredient in glass, computer chips, and certain gemstones- rock crystal, agate, rhinestone, amethyst. Opal.
The human body contains approximately one gram of silicon, ranging from 4 ppm in blood, 17 ppm in bone, and up to 200 ppm in various tissues. Cereal grains are our primary source of dietary silicon. Silicon is seldom found as a pure element, because it has a high affinity for oxygen. It is this ability to scavenge oxygen that makes silicon important in steelmaking. Silicon’s primary role in steel making is as a deoxidizer. It makes steel sound, by removing oxygen bubbles from the molten steel. The percentage of silicon in the analysis was related to the type of steel, rimmed and capped steels (made by the ingot method) had no silicon intentionally added. Semi-killed steels typically contained up to 0.10% max silicon, and fully killed steels could have up to 0.60% maximum. Commercial practice in the US and Canada throughout my career was 0.15-.35 % silicon in SAE carbon and alloy steels. In addition to deoxidiation silicon also influences the steel five different ways:
Silicon helps increase the steel’s strength and hardness, but is less effective than manganese in these functions.
In electrical and magnetic steels, silicon helps to promote desired crystal orientations and electrical resistivity.
In some high temperature service steels, silicon contributes to their oxidation resistance.
In alloy grades, silicon also increases strength (but not plasticity!) when quenched and tempered.
Silicon also has a moderate effect on hardenability of steel.
But there are always less desireable aspects of any element in an alloy
Silicon is detrimental to surface quality in low carbon steels, a condition that is especially magnified in low carbon resulfurized steels.
Silicon is detrimental to tool life in machining as it forms hard abrasive particles which increase tool wear and thus lower the steel’s machinability.
Bottom line, on plain carbon and alloy bar steels, silicon contents of 0.10, 0.15-.35 weight percent are typical; On resulfurized , and resufurized and rephosphorized free machining steels, silicon analysis above 0.02 wt % is cause for concern, due to potential surface quality and certain tool life issues. Silicon metal photo Opal
As a Lab supervisor in a Metalurgical Lab, quality pictures through the microscope was all in a days work.
Obtaining an appropriate sample.
Using the tools at hand to create an appropriate image.
It was easy to desire better tools, more powerful microscopes etc. But the proof of the image was more about our mastery of our tools and craft than it was about equipment.
As you will see on the Nikon Small World Competition site, these photos are “out of this world” and go far beyond what would be considered routine. These folks have mastered their tools.
I am waiting for a high res photo of #18 by Gerd Guenther of Dusseldorf to add to this post. Believe it or not his image is of soap film-LIKE WE USE TO CLEAN OUR HANDS- OR WASH OUR PARTS.
Enjoy the images. Its a different world under the microscope.
Be amazed at the elegant complexity and order revealed at the smallest levels visible to us with light.
“The jobs crisis has brought an unwelcome discovery for many unemployed Americans: Job openings in their old fields exist. Yet they no longer qualify for them.”
According to an article in the New York Times (link below) this is
A trend that took root during the recession.
Companies became more productive by doing more with fewer workers.
Some asked staffers to take on a broader array of duties – duties that used to be spread among multiple jobs.
According to Mark Tomlinson, executive director of the Society of Manufacturing Engineers, “there are jobs available, but the worker just has to have more skills than before.”
The trend means “employees increasingly must be able to run the computerized machinery that dominates most assembly lines. They also have to carry out additional tasks, such as inspecting finished products,” said Tomlinson. It’s no longer “I just show up and do my job and someone tells me what to do.”
Human resource specialists say employers who increasingly need multi-skilled employees aren’t willing to settle for less. They’d rather wait and hold jobs vacant. HR specialists have a nickname for the highly sought but elusive job candidate whose skills and experiences precisely match an employer’s needs: the “purple squirrel.”
“There are lots of requests for purple squirrels nowadays,” said Joe Yesulaitis, chief executive of Aavalar Consulting, an IT staffing firm.
One of my favorite quotes is by Robert Heinlein, from his “Notebooks of Lazarus Long” “A human being should be able to change a diaper, plan an invasion, butcher a hog, conn a ship, design a building, write a sonnet, balance accounts, build a wall, set a bone, comfort the dying, take orders, give orders, cooperate, act alone, solve equations, analyze a new problem, pitch manure, program a computer, cook a tasty meal, fight efficiently, die gallantly. Specialization is for insects.” I’d hire the person Heinlein is describing! Are you a Purple Squirrel?
Here is a link to the article: NYTIMES Purple Squirrel
A number of customers of the precision machining industry have started telling their suppliers (Us!) that we need to adopt SMED (Single Minute Exchange of Dies) Techniques so that we can reduce costs. We make it a rule never to prescribe solutions when we haven’t first diagnosed the problem…
Reducing setup time is important, but if that is not the constraint that is limiting your ability to serve your customer, why would you address that first?
The real issue that the customer has not brought to the table is lot size, economic order quantity (EOQ). Given an order quantity of 100 parts, if changeover time is 8 hours on a part with a one minute cycle time
to make his parts originally takes 480 minutes of set up time.
Plus 100 minutes (100 parts at one minute per part) to produce;
Total 580 minutes or 5.8 minutes time per part.
The setup time is 480% of the actual process time to make the parts. 480/100= 480%
Reducing the set up to 4 hours set up, its now 240 minutes set up time plus 100 minutes to produce total 340 minutes or 3.4 minutes time per part. The setup time is now just 240% of the actual process (Cutting) time. The customer is saying that you should do this. And as far as you can, he is right. But lets look at what the customer’s order quantity does to affect this.
Increasing just the lot size from 100 to 1000 pieces
Results in the time per piece on the 8 hour setup being 480 minutes for set up plus 1000 minutes, or 1.480 minutes total time per part.
The ratio of setup time to total time is now just 48%of the process time.
THATS A TEN FOLD REDUCTION!!! This is where the Bang for the BUCK is! If you could get your setup down to four hours, you’d be at 24% ratio of setup to total time.
On 10,000 pieces it becomes, at 8 hour set up, 480 minutes setup plus 10000 minutes process time; or about 1.048 total time per part; 4.8% is the ratio of set up to the process time.
WE CAN SEE that while reducing set up time is important and something that you can control, It is the increase in the lot size that is the most powerful determinant of the amortization of cost of setup. And your customer holds those reins. ECONOMIC ORDER QUANTITY is in your customer’s control and ultimately delivers drives far greater savings than your cutting set up time in half, and in half again as we have just shown.
What he wants to ignore is that you have to set up the machine regardless of his lot size and he has to pay for it. So he wants you to reduce that set up as much as possible. However, there is no free lunch, there is always a law of diminishing returns, and he has to give you an order quantity that makes it profitable for you to set up your machine and produce the number of parts required. Reducing setup time is important, but if that is not the constraint that is limiting your ability to serve your customer, why would you address that first?
Just cause that medicine sounds good to you Mr. Customer, doesn’t mean that it is the magic cure for everything. Increasing your Order Quantity may actually drive substantially larger savings.
Built Up Edge (BUE) is the accumulation of workpiece material onto the rake face of the tool. This material welds under pressure, and is separate from the chip.
In school we were taught that this is because the first material to contact the tool workhardens, and we did hardness tests to confirm this.
Because BUE changes the effective geometry of the tool, it can have either positive or negative effects. Positive effects
Less tool wear
Lower power requirements
Less contact of the workpiece with the tool (It contacts the BUE instead)
Better surface finish and improved process capability
These effects are only beneficial if the BUE is thin and stable. Machining additives such as sulfur combine with manganese to form manganese sulfides. Manganese sulfide helps to control BUE because of its anti weld properties. On resulfurized steels, BUE is usually stable and not a problem. Negative effects
Poor tool life
Poor and variable surface finish ( As the BUE sloughs off the tool, it can weld to the workpiece)
Loss of statistical capability on dimensional control
Loss of uptime trying to troubleshoot the process
I have found that BUE is more likely on alloys that work harden. In order to get BUE under control, the steps that you take depend on the tool material. For Carbide
Decrease the feed. (Pressure welding usually is the culprit)
Increase the speed
Increase the rake angle or “hook”
Get a better metalworking fluid (including get the fines out of your existing MWF!)
Get a different coating
For High Speed Steel (HSS)
If the tool is High Speed Steel (HSS) you may think you are in oppositeland when you discover that slowing down the speed reduces the build up. I have found on HSS that as speed (heat increases) so does the tendency to form BUE. Graphic.