yet again, frod don't heat treat springs AFTER COLD FORMING. that is breaking the #1 cardinal rule for spring manufacture because POST FORMING HEAT TREATMENT removes residual stress. instead, frod just "bulldoze", and don't peen. this gives crappy [but CHEAP!] springs that break.
I mentioned that the wire is heat treated prior to coiling as industry common practice several times. The fact you don't understand how parts need to be handled in heat treating is your problem, not mine.
So it's true that you can't read and comprehend. You have that so incredibly twisted by your own personal biases that it's really quite sad. Go read it again and again until you figure it out. Also try to notice that this is a proposed process that has not been implemented in production at the time of the article.
Hint: Figure 2 is the bar stock. The wire as recieved. It represents the cold-coiled spring. Figure 3 is the as-tempered spring. Read the caption: "The data for the as-bulldozed spring, though not given here, look essentially the same."
Reading is fundamental.
No where does the article state that Ford cold coils production springs without stress relieving. It doesn't state how Ford makes springs at all. It implies that they do stress relieving and hence are investigating ways to achieve the same result at lower cost.
Your mental gymnastics are amazing. It's not just a reading comprehension problem with you, you're altering the text in your mind to suit your biases.
As to the drawing, you cannot determine a part met specification without the specification. That's part of your claim, that a failed ford part meets the print while spring failures from Honda or others are just mistakes, 'statistical anomalies where the part didn't meet the print. You need the specifications to show that part of your claim.
PROVE IT. There is nothing in the article that discusses production springs. The article you cite discusses a proposal for cost reduction which results in same stress relieved condition. Here's the relevant paragraph you can't get straight:
"We have looked at three cold-coiled springs. The first spring is an as-cold coiled spring. The second one is cold-coiled followed by a relatively low temper. The third one is identical to the second one, but in addition to being tempered the spring has been com- pressed to the point where the length of the spring is equal to the number of windings times the wire thickness. After this the spring was allowed to relax. A small part of this torsion strain is in the plastic region, so this spring is slightly shorter than all the others. In the automotive industry this process is known as .bulldozing.."
_The third one is identical to the second one, but in addition to being tempered the spring has been com-pressed_
In addition to being tempered. Got that? IN ADDITION TO.
Give it up, in Jim's mind, to paraphrase Mike Myers, "if it isn't Honda, it's crap!"
Never mind that Honda have started using MacPherson struts on their newer models, one of Jim's constant complaints about everyone else.
nate
but they /are/ production springs!!! they have been for decades. the only thing novel about that paper is the use of neutron diffraction which allows actual in-situ measurement of residual stress levels as opposed to empirical extrapolation and modeling.
[the use of taxpayer dollars to do frod's research for them is another debate.]it's "tempered", PRE DEFORMATION!!! got that?
seriously, if you don't understand that fundamental distinction, you're just howling at the moon.
i understand, but you don't. cold forming introduces residual stress. "heat treatment" prior to cold forming does not remove residual stress. it is completely irrelevant to what you're trying to say and your continuing to not understand that completely negates any argument you think you have.
unbelievable - "cold coiled" is not "bar stock", it's the cold coiled spring.
!!! no, that "temper" is pre-deformation. #3 gets no stress relief from tempering, just "bulldozing"!!!
" Read the
you got that right. shame you can't do it.
it does "stress relieve", but only by "bulldozing", which is cheap, and inferior.
???!!! it most specifically does!!!.
they "stress relieve" by bulldozing. only.
coming from a guy that can't read, that's ridiculous.
these parts "meet specification". the spec is "cheap" and /includes/ failure.
indeed - the spec is inferior - cheap. failure is not just anticipated but expected.
no, i need to find someone who can teach you to read.
your reading comprehension failures are well known. shame you can't contribute anything of value here.
i've criticized honda long and hard. [see reading comprehension failures above.]
What are your qualifications?
jim beam wrote in news:ksbjmp$anb$ snipped-for-privacy@dont-email.me:
And that was my very point.
Your original, and absolute, comment: "frod don't heat threat - it saves money".
Why would Ford bother putting out a document that specifies how heat-treatment must be done if they don't heat-treat?
Once again you're applying assumption and bias. The article is about an alternative method to eliminate residual stress. It does not discuss what Ford does for production springs. You have offered zero proof of your claim in that regard. The article states that springs are commonly manufactured by hot rolling followed by heat treatment or heat treatment of the stock wire followed by cold forming followed by tempering to eliminate residual stresses.
It's heat treated before coiling. It's tempered afterwards to eliminate residual stress. If that is obvious from the article's consistent use of terms, something you have a huge problem with, it should be obvious by looking at figures 2 and 3 and reading the captions.
You're a real piece of work.
It's you who can't read and can't understand and can't even use the correct terms. Once again you're confused and unable to communicate properly. You argued Ford doesn't heat treat springs, that is to harden. Then later on you changed to 'ford doesn't stress relieve' You keep flipping back and forth, but you're wrong and you're wrong. The material is heat treated, the spring is formed, and the spring is stress relieved or the spring is hot coiled and then heat treated. One of those two. So you're just plain wrong.
Can you not read simple english? Here I'll cut and paste it for you:
"FIGURE 2. Contour map of the residual stress in the direction of the length of the coiled bar stock, plotted on the bar stock cross-section. With reference to Fig. 1, this is the tangential direction. This map represents the as-cold-coiled spring."
The temper is after. READ THE article: "Generally, there are two ways to coil a spring: hot coiling and cold-coiling. Hot coiling implies that the spring is wound from stock at or above the recrystallization temperature. The strength and fatigue resistance are controlled afterwards by an appropriate heat treatment. Cold-coiling means that the helical winding takes place at a low temperature after the spring has been hardened and tempered. Cold-coiling allows the high temperature heat treatments to take place on the bar stock, which is easier to handle than the coiled end-product. The resulting residual stresses can be essentially eliminated by a relatively low temperature tempering treatment fol- lowing the cold coiling."
Tempering happens after forming. Your backyard learnin' plus your biases plus your arrogance has made you the fool again.
Hardening happens before coiling. Tempering happens after forming. It's that simple. But because of your backyard learning you are using all three terms as equals. They are not.
Tempering != hardening.
Article states no such thing.
No it does not. Please learn to read.
Prove it. Article says no such thing. The article is an evaluation of a shorter tempering plus bulldozing.
"The third one is identical to the second one, but in addition to being tempered the spring has been com-pressed"
Wire->Hardening->coiling->tempering->bulldozing is the proposed process.
Stop projecting.
PROVE IT.
PROVE IT. Support your claims.
Tempering != hardening.
When you can learn to communicate properly let me know.
no, you're putting your mis-understanding into my mouth, not what i said.
no, you've failed to understand and you've cut context. they stress relieve, but only by "bulldozing", hence figs #2 & #3.
so they can coil it without cracking. but it doesn't stress relieve - #2 proves that.
you're missing the cold coiling steps. conventional is cold coiled, then *heat treated* to stress relieve. frod cold coil and bulldoze to stress relieve. #3 proves that.
that's the residual stress profile that results from cold coiling. not tempering. not hardening. #3 is that resulting from "bulldozing". not tempering. not hardening.
that's talking about the conventional cold coil process, the one in vic's cite and the one i told you that frod short-cut because it saves money. two paragraphs later, it goes on to describe the actual samples
- where frod bulldoze AFTER coiling. they rely on that as their sole means of stress relief. #2 and #3 shows why this short-cut "works".
you're the one that seems confused by the different terms - i never mentioned hardening resulting from heat, just cold work. if you don't understand that difference, you need to ask for help, not take offense at imaginary criticism.
true. but i never said it was, so don't try and make it sound like i did.
then you have no business trying to argue here because you can't read. #3 IS the result of "bulldozing" and it PROVES that stress relief has occurred from a cold mechanical process, just like i've said all along..
but the neutron diffraction profile clearly shows that the "tempering" used here does not stress relieve. and without that, this is not a conventional spring production method.
i can't "prove" anything to someone that can't even read, much less to someone bent on twisting what someone does or doesn't say.
that's either a reading comprehension failure or another false accusation because i never said it was.
irony, you missed this guy completely.
that is the conventional route, but it's not what frod do. #2 proves that.
if you can't read, at least look at the pretty pictures. it's crystal clear - the difference between #2 and #3 shows that being "bulldozed" after cold coiling is what's mitigating residual stress. it's also why the paper is titled "residual stresses in cold coiled automotive springs".
if only you understood the irony of that!
we were talking about springs. i was talking about springs. if you don't think that's clear, that's a shame, but it's not an excuse to say someone said something something they didn't.
The article doesn't prove anything about production methods. Only a clueless fool with no real experience would think it does.
Figure #3 shows the _tempered_ spring. The caption says the tempered and bulldozed spring is similiar. Stop projecting your own defects on to me.
Go back under your bridge.
no, you're mis-stating what it says. #2 is tempered*. #3 is #2, after bulldozing. only.
i'm not - you're getting your own defects out there all by yourself.
"We have looked at three cold-coiled springs. The first spring is an as-cold coiled spring. The second one is cold-coiled followed by a relatively low temper. The third one is identical to the second one, but in addition to being tempered the spring has been com- pressed to the point where the length of the spring is equal to the number of windings times the wire thickness. After this the spring was allowed to relax. A small part of this torsion strain is in the plastic region, so this spring is slightly shorter than all the others. In the automotive industry this process is known as .bulldozing.."
...
"FIGURE 2. Contour map of the residual stress in the direction of the length of the coiled bar stock, plotted on the bar stock cross-section. With reference to Fig. 1, this is the tangential direction. This map represents the as-cold- coiled spring. The left and right side of the map represent the convex and concave sides respectively"
"FIGURE 3. Same as Fig. 2, these data representing the as-tempered spring. The data for the as-bulldozed spring, though not given here, look essentially the same."
It is you who doesn't understand. Stay in your back yard until you learn how to properly read and communicate.
I'll just keep repeating what is clearly written until you can finally read and comprehend it.
"We have looked at three cold-coiled springs. The first spring is an as-cold coiled spring. The second one is cold-coiled followed by a relatively low temper. The third one is identical to the second one, but in addition to being tempered the spring has been com- pressed to the point where the length of the spring is equal to the number of windings times the wire thickness. After this the spring was allowed to relax. A small part of this torsion strain is in the plastic region, so this spring is slightly shorter than all the others. In the automotive industry this process is known as .bulldozing.."
...
"FIGURE 2. Contour map of the residual stress in the direction of the length of the coiled bar stock, plotted on the bar stock cross-section. With reference to Fig. 1, this is the tangential direction. This map represents the as-cold- coiled spring. The left and right side of the map represent the convex and concave sides respectively"
"FIGURE 3. Same as Fig. 2, these data representing the as-tempered spring. The data for the as-bulldozed spring, though not given here, look essentially the same."
I'm not going to argue with you. I am just going to keep cutting and pasting the parts you can't comprehend.
"Generally, there are two ways to coil a spring: hot coiling and cold-coiling. Hot coiling implies that the spring is wound from stock at or above the recrystallization temperature. The strength and fatigue resistance are controlled afterwards by an appropriate heat treatment. Cold-coiling means that the helical winding takes place at a low temperature after the spring has been hardened and tempered. Cold-coiling allows the high temperature heat treatments to take place on the bar stock, which is easier to handle than the coiled end-product. _The resulting residual stresses can be essentially eliminated by a relatively low temperature tempering treatment fol- lowing the cold coiling._ "
"We have looked at three cold-coiled springs. The first spring is an as-cold coiled spring. The second one is cold-coiled followed by a relatively low temper. The third one is identical to the second one, but _in addition_ to being tempered the spring has been com- pressed to the point where the length of the spring is equal to the number of windings times the wire thickness. After this the spring was allowed to relax. A small part of this torsion strain is in the plastic region, so this spring is slightly shorter than all the others. In the automotive industry this process is known as .bulldozing.."
...
"FIGURE 2. Contour map of the residual stress in the direction of the length of the coiled bar stock, plotted on the bar stock cross-section. With reference to Fig. 1, this is the tangential direction. This map represents the as-cold- coiled spring. The left and right side of the map represent the convex and concave sides respectively"
"FIGURE 3. Same as Fig. 2, these data representing the _as-tempered spring_. The data for the as-bulldozed spring, though not given here, look essentially the same."
why are you repeating stuff you clearly don't understand??? [rhetorical] it doesn't support what you think you're saying.
You need to re-read it. Eventually you'll grasp it. Maybe.
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