Design and Fabrication of Bending Roll Machine

Insufficient information: How far apart are the smaller rollers?

#1

The distance between the two bottom rollers is 96mm.

You are asking an impossible to answer question!

As Tornado said, if this is all you know about your project you only have a million to one chance of success.

If I had no clue what I was doing, and was wishing for such a machine, I'd find a machine on Google that did what I wanted to do, and BUY it. Or, at the very least copy the design. That will answer your question about motor size, too.

Anything that you cobble together yourself is doomed to fail, because there are many critical components that you have not defined.

Sir please explain it me, why it's not possible? And please list the difficulties of this project if you can. I will respect your reply sir...

No.

You list or show the forum what work you have done.

Any research?

Drawings?

Force calculations?

I agree with Lyn's answer. I have never designed a plate rolling machine. Here are a few things I would consider :

A. What type of material is going to be rolled.

B. Are all of the parts for the machine going to be constructed from raw materials or are any of the parts going to be off the shelf items.

C. With respect to the rollers, what material will these be made from, how will they be supported, what type bearing will be used, how will the bearing be supported, what is the design of the end flange, how many of the rollers need to be driven, gear,chain, direct.

Only a few of many to consider.

Have fun with your project.

Why do you want to re-invent the wheel? Many companies have been making similar machines for at least a century. Through engineering and experience, they have reduced or eliminated most sources of failure, both in the machine and in the product. These are not expensive machines (depending on production rates required and on the kind of material being rolled)!

I need to execute this project in the industry sir, you are right. But unfortunately I get this topic.

Sir,

I understand from your posts that this is a job assignment from an employer, and the purchase of a machine is not possible (for whatever reason). I am not an engineer and cannot answer your question(s). However, additional information would be needed to even come within a crude approximation of the answer(s). This would include the speed or production rate that is needed, the type of material (including its properties that influence its "bendability", and the amount of time you have for trial and error.

If you design a machine that overloads the driving motor(s), then you would have to either install more powerful motors and gearing, or a gear box with a lower output shaft speed. Also, the machine's mechanical components would have to be stronger than the forces imposed (on the shaft, bearings, and adjusting mechanism) by the resistance of the plate to being bent.

I wish you success.

--JMM

This is starting to look suspiciously like a school project.

In any case, you don't seem to know how to proceed.

Homemade Metal Bender: 3 Steps

How to make a DIY Sheet Metal Bending Brake - YouTube

Homemade Metal Bender - YouTube

Get some help.

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"I get this topic." So I gather it is an assignment, either from a teacher or from a penny-pinching employer, or possibly from an employer who wants to find out your capabilities...

So download drawings/photos/specs of several existing machines, and see if you can find any way to improve upon them (use higher quality materials, stronger supports & bearings, lower friction at bearings, higher friction on roller surfaces, etc.).

Sounds a lot like a homework problem... but maybe it is just some oddity at you actual job. Either way, it doesn't help you to do the work for you.

I am willing to make suggestions about how to approach the problem.

Assume that the shert surface is tangent to the roller outer surface.

Including the sheet thickness and roller thickness, calculate the minimum height the top roller can be above the plane of the bottom rollers without bending the sheet. (35mm+50mm+6mm)

Next calculate the minimum height the top roller can be above the plane of the bottom rollers without decreasing the thickness of the sheet. This height is one leg of a right triangle, the other leg is half the separation of the lower rollers and the hypotenuse is the same as the height in the first caculation above.

The first calculation is the starting point, the second corresponds to a bend (neglecting springback of a percent or few) where the ID of the sheet being bent matches the surface of the roller.

Knowing the sheet wilp be perpendicular to the roller where it contacts, calculate a few additional points between those two extremes. Graph the results. Look for the relationship, or cheat and let a graphing program calculate the best fit curve formula for you.

Your post suggests that you are asking others to design this machine for you?

Sir I'm a student, not having much knowledge about this machine and the design considerations, for this reason I need full support from your side. And I'm kindly requesting it in front of you sir.

Fine,... what do we have to work with.

Doing design of a piece of machinery... you must be in your 3rd year of college.

What courses have you completed.

• Machine Design?
• Metallurgy?
• Statics/Stress Analysis?
• FEA?
• Manufacturing Processes
• etc...

would help.

Sir, presently I'm pursuing M Tech, in Production Engineering and System Technology. I'm in the last semester which mainly dealing with the execution of project and submitting report within duration of 4months.

Sounds more like your report consists of Project Management for the development of a Bending Roll Machine.

Design and fabrication is not the first step.

First of start out with identifying your goals. (and by the way, your goal isn't Design and Fabrication of Bending Roll Machine)

An example; Your goal is what material, size and to what extent you want this machine to accomplish. Also include budgets....

This also would include the quality your expect.

Sir, the main title of the project is "design and fabrication of the bending roll machine"

The considerations are like this

- minimum diameter of the shell must be 100mm, max upto 500mm.

- motor have to use as a source for rotation of the rollers with the desired torque.

The top roller dia will be 80mm and bottom rollers will be 70mm.

The thickness of plate will be 6mm, width of 1000mm.

We need 20 rpm of the rollers

You want rollers or are you open on what type of process?

Sir not like this type. I need a bending a plate of metal having some thickness , length and width to form pipes or cylinders and conical hoppers etc..

If I understand correctly;

With the top roller has 80mm dia and the bottom rollers has 70mm dia.

With a minimum of 100mm finish diameter? with a material thickness of 6mm

You may be are asking a lot for the rollers... with the rollers being able to do 1000mm of work, they would have to be as a guess, at the very least 1500mm long. (for a conical shaped hopper)

Normally, we would use a brake press for doing conical shaped hoppers.

I just received a quote for a 24" Max OD x 1" Minimum OD x 30" long hopper made from Stainless Steel, and the company that quoted it is having it spun. (interesting enough)

U r right sir, Dia from 100mm to 500mm will be accepted,

One of our standard procedures is to roll cones having an OD around 4'-5' of ≈0.040" Inconel from flat sheet. The flat blanks are referred to as "smiley faces".
If I recall correctly the rolls are all in the range of 80-100 mm OD, and between 1.5 and 2 meters long. They are powered by one or more motors controlled by VFD, with hydraulic control of the roll positions.

.040" is a little more than 1mm. Now try it with 6mm which is almost 1/4" (0.236")

It would be a struggle.

Yes, I (We) had rolled 10 gauge stainless cones. and would brake one end.

You'd get some gauling, but a seasoned fabricator (not me) can do it with a minimum of gauling.

Please, you're a student looking for someone to do your work for you. All the answers you need are available on the web (for free) in under 0.4 seconds, just use your favorite search engine and insert the title of your thread. Hurry up, the students in your class have already done so and are 4 months ahead of you.

Thank you sir,

You're welcome. Please remember that you will get far more help here if you tell the members the results of your own prior effort, exactly where you are in need of extra assistance, and why you're stuck.

What production rate are you planning for? and for how long will the plant work in years or months?

Hi sir, I'm just an intern in an organization, I'm not clear about their demands and needs. They just assigned this as a project to me, Sir.

Okay. Go to your books and know to calculate the forces needed to bend the metal sheets assigned to you. Get the distances of the bend and you have the work of the assignment. Next think how quickly the work is to be done and you have the power. Next estimate the approximate speed of rotation of the rollers. Get an appropriate gear system to drive the rollers and which will at the same time step down the speed of the motor (say 1500rpm of the motor to 1rpm of the roller). Make allowance for the greatest force needed to bend a steel sheet. The power needed from your calculation will give you the idea of the motor size. Next, which type of motor? Find out from the internet the right type and the reason why that type is recommenced. For durability get the next size larger motor. Make convincing diagrams and calculations and present to you engineer. He will fill the gaps and you have a pass in your project.

Thank you sir,

A couple of years ago I had the same question from an indian who claimed that they had not the money to buy and wanted to build such a machine.

In order to help I made a full analysis which is somewhere on CR4 to be found.

Several years later an error I made was noticed and I made the correction ie I accepted the remark.

Digg in the CR4 history and you will find every thing you need for your project.

It seams that in India making in stead of buying is very common.

I take this opportunity ti wish the best for CR4 for the started Year

Nick

"It seams (sic or pun?) that in India making in stead of buying is very common."

Or perhaps it may be that in India, they understand more so than many institutions here, that an engineer can't do the best job possible if (s)he has never actually designed and built something, and experienced some of the inevitable problems (and most likely failures) in the process.

Designing and building a plate/sheet rolling machine would be an excellent experience for a young engineer or engineer-to-be, and if successful, would leave the school with a machine they could use or sell.