Problem with cutting steel bars
Problem with cutting steel bars
(OP)
Hello all.
I have a problem where I work and want your help.
At forging, when the steel bar is cut, sometimes the bar sticks to the "cutting blade". Then, it takes different shape than the normal one and a defect appears. The process is mechanical, no cutting disc is used.
It's like the bar acts like a dough.
What can we do so this problem doesn't occur?
Thanks in advance!
I have a problem where I work and want your help.
At forging, when the steel bar is cut, sometimes the bar sticks to the "cutting blade". Then, it takes different shape than the normal one and a defect appears. The process is mechanical, no cutting disc is used.
It's like the bar acts like a dough.
What can we do so this problem doesn't occur?
Thanks in advance!





RE: Problem with cutting steel bars
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Of course I can. I can do anything. I can do absolutely anything. I'm an expert!
RE: Problem with cutting steel bars
The sticking ones are either too hot, or not enough lube, or both.
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Plymouth Tube
RE: Problem with cutting steel bars
RE: Problem with cutting steel bars
I thought about lubrification but need to investigate the problem more.
Thanks guys.
RE: Problem with cutting steel bars
the way you said it is " heated by induction and then cut" I'm assuming you heat just the section you want to cut, perhaps because it is a thick section.
Does the "defect" resemble the edge on this cold sheared plate?
http://images.discountsteel.com/files/image/oms_pr...
RE: Problem with cutting steel bars
RE: Problem with cutting steel bars
The "goo" squeezes the blade as it seeps back into the cut (think Panama canal's Gailliard Cut: As you remove material more flows back into the groove and gums up the teeth).
RE: Problem with cutting steel bars
Saw cutting a hot steel part may likely result in some welding between the blade and part surfaces. It would be better to saw cut the material while cold so a cutting fluid can be used. If you really need to trim the material while hot, you might consider using some type of shearing or trimming die.
RE: Problem with cutting steel bars
racookpe1978, I think you're very accurate with what you said.
I informed myself a little better about the problem.
When the guillotine makes the first "cut" , it goes blank 3 more times(it's idling) without cutting, and it goes by the bar that's advancing little by little. This is where sometimes the problem occurs.
I hope my English is not that bad and you guys understand the process that I'm explaining.
RE: Problem with cutting steel bars
What are blade approach temperatures, blade removal surface temperatures? That blade is very thin - it will heat up quickly!
RE: Problem with cutting steel bars
RE: Problem with cutting steel bars
RE: Problem with cutting steel bars
Your English is fine, but your communication would be enhanced with a sketch.
- Can you sketch the cut end with and without the defect?
- can you sketch what the guillotine and the support provided for the bar during the cut look like?
- does the bar continue to advance during the cut operation?
RE: Problem with cutting steel bars
Thanks for the partial clarification. So what I understand so far is that you are locally induction heating a piece of wrought steel bar and then cutting the bar at the heated area using a single blade shearing operation. But for some reason you are not getting a clean separation at the shear plane. I assume you are using a machine designed specifically for hot shearing steel, but have you checked to see if you are using the proper blade and machine settings for the material type, size and shape you have? Also, as others noted, are you sure the material has the correct temperature all through its thickness when it is being sheared?
More specific details about the machine and settings used, material composition and form, process variables such as temperatures, cycle times, etc., and some photos of the defective cuts would be extremely helpful.
Regards,
Terry
RE: Problem with cutting steel bars
But the process is like 20-30 years old and the temperature I think it's good, maybe needs a little optimization.
Only sometimes this problem occur. Now engineers are investigating the problem.
When I'll have more details, will let you know. I hope tomorrow.
btrueblood, I will make a sketch when I'll get into more details of the problem.
Thank you again.
Be back soon with more details.