Greetings,

We are planning to manufacture Copper Strips for transformer windings, the width is between 250 mm - 600 mm and the thickness is between 0.30 mm - 0.80 mm. There is a new copper extrusion machine, called a Conform machine (BWE CONFORM UK or DALIAN KONFORM CHINA), where we will able to extrude 320 mm wide - 10 mm thick Oxygen Free Copper Strips. Is there any rolling process while we can reduce the thickness of the raw strip and we can also enlarge the width of the strip.

Hello,
I just checked the specs on the BWE Conform machine and the largest width it mentions is 125 mm and a total are of 2,400 mm square. If that is so I am not sure how you will be able to make 250 to 600 mm wide. Did you mean really mean 0.30 mm to 0.80 mm thick? 10 mm thick seems to be within the range but on their spec sheets they list max width and max area.

Since you are not going from conform machine continuously into the enameling system, any rolling mill should allow you to reduce the thickness. You will probably need to have an anneal process and then flattening with 2-3 stands as well as 1 or 2 edging stands. If you are going to go from 10mm to 0.3mm that is a huge reduction.

Since the conform machine can make smaller sizes why not start thinner?
spectre

Hello Spectre,

Thanks for your reply. That was my first post in the forum. I will try to be more clear to get the right answers from experts like you here in the forum. Please check the below website:

www.shdljxc.com/03600074/php/picshow.php...id=129019&lang=0

You can have a better idea about what I want to do. The strip in the photo has 320 mm width and the thickness is 16 mm.

Just as in the picture, just after the water cooling I would like to put several necessary number of single 2 high rolling stands to make primary cold rolling of the strip down to 3 mm. And then to roll it in a 4 high rolling mill down to 0,10 mm.

My question is, 320 mm width is not enough to meet all of my customers' demands, so I would like to learn if there is any rolling technology to increase the width of the strip during rolling. For example: Inlet is 320 mm x 16 mm, after width enlarging rolling we will go down to 500 mm x 3 mm.

Hi spectre,

I could make no sense from the URL posted by rezzak53 because even if the first page is translated to English, all the other pages were in Chinese. Moreover all pictures are so small that I could not tell exactly what was going on.

Dalian Konform Technical Co., Ltd.
I did check out the Dalian Konform Technical Co., Ltd. web site www.konform.cn/en/index.htm and it stated that the maximum output for rectangular copper had a width of 50 mm (TLJ300) and a maximum cross-section area of 250 square millimeters. (That would calculate to a maximum thickness of about 5.0 mm)

Now to roll that down to 0.3 mm would give a maximum width of 833 mm Likewise, a thickness of 0.8 mm would give a maximum width of 312.5 mm.

This Dalian Konform machine therefore does not meet rezzak53's specification.

BWE Ltd Conform
I also noted that the Conform model 550 machine had maximum width of 120 mm and a maximum cross-section of 2400 sq mm. This would give a maximum thickness of 20 mm. (The minimum thickness is 12 mm.)

A 600 mm width at a 0.8 mm thickness gives a 480 sq mm cross section so the output of the machine needs to be reduced to a maximum width of 40 mm and a thickness of 12 mm. That equals a cross section of 480 sq mm.

This Conform machine and possibly smaller models comply with rezzak53's specification.

I imagine all rolling and annealing would be by separate operations.

Note
Just a small note to rezzak53 "Sir, the Conform machines are nothing new and have been around for decades."

Best Personal Regards
Peter J. Stewart-Hay
Principal
Stewart-Hay Associates
www.Stewart-Hay.com
519 641- 3212

Peter,

0.3 mm is about 1/75 of 1 inch or about 0.012 inches. 0.8 mm is about 1/30 of an inch or about 0.031 inches. That's pretty thin, especially the 0.3 mm.

I figured that was a mistake 320 mm x 16 mm is way beyond the capabilities of the conform machine web site I was looking at.

320 mm wide is just over a foot. 600 mm is nearly 23 inches wide. Even if that number is correct, I'm not sure how you would properly coat it.

Hi Spectre,

I'm sorry, I guess I didn't make myself sufficiently clear.

According to the information at www.bwe.co.uk/webpages/Conform550.pdf , the minimum copper thickness is 12 mm, the maximum width is 125 mm and the maximum area is 2400 sq mm.

A 600 mm width with a 0.8 mm thickness gives a maximum area of 480 sq mm so the Conform machine would have to extrude a copper strip 40 mm wide by 12 mm. thick. (480 sq mm)
A 250 mm width with a 0.3 mm thickness gives a maximum area of 75 sq mm so the Conform machine would have to extrude a copper strip 6.25 mm wide by 12 mm thick. (75 sq. mm) but I think instead it would have to extrude a copper strip of at least 12 mm by 12 mm (144 sq mm)

What I meant was after that extrusion, sizing would have to be done by off line rolling and annealing. if at all possible.

I wonder if the final thin, flat copper strip would be insulated by electro-deposition which I understand has become rather popular for thin rectangular magnet wire. See www.mitsubishi-cable.co.jp/en/product/finerect/index.html

By the way, Canada is a metric country so we are pretty much bilingual in metric and imperial measures.

Best Personal Regards
Peter J. Stewart-Hay
Principal
Stewart-Hay Associates
www.Stewart-Hay.com
519 641- 3212