We currently insulate our wire with a polyvinylformal enamel. We manually fill up a reservoir that the wire passes through to pick up the enamel. We are looking for some help in going from a manual system to an automatic system that will pump enamel to the wire and will also control the viscosity of the enamel by adding a solvent. Does anyone know of a company that can supply a system like this? Or give me any information that may be useful in this? Thanks for any help you can give.

Posts: 1013
Joined: Feb 2004

Hi Mark,

There are a couple of expert magnet wire engineers that monitor this forum so shortly you should get some really good advice from one or both of them. A little patience please. Thank you.

Best regards,
Peter J. Stewart-Hay
Principal
Stewart-Hay Associates
www.Stewart-Hay.com

Hello Peter, Mark C.
As Mark probably is aware Formvar is a very low solids material. I've got a couple of questions that the answers would lend toward providing answers.

What size wire are you coating?
How much enamel are you putting on the wire; single, heavy, triple, quad build?
Is there an overcoat?
What is the end product or use of the finished wire?
How much wire or enamel are you using per hour?
What kind of applicator are you using; dies, felts, roller, etc?
All of these answers go toward determining what type system might work best for you.

richard/spectre engineering

Hello Richard,
Here are some answers:
Wire size is .004" - .050" most common .020" - .030"
Single build
No overcoat
Superconductor wire
On one oven the emamel usage is 4-5 gallons/day
We use soild dies
The type of Formvar that we use is described as a high soild magnet wire enamel (not low). Hope this helps.

I did it again, took too long to post and answer and then lost my answer.

Don't know what you call high solids formvar but according to supplier info I looked at typical is 15-20% for formvar. Other enamels start at about 30% and go to 60% solids.

How many lines do you have on a machine? How many passes are you making through an oven?

Your most common size is about 22 awg. 4-5 gallons of enamel usage yields between between 600 and 800 pounds per hour. For a single line oven this would be about 30 lbs./hour and this would probably equate to a speed between 150 and maybe 250 feet/minute. How right might this be?

rb

Not sure about the amount of soilds that our Formvar has. The description that I have for the Formvar is "high solids polyvinylformal magent wire enamel." It may be in the 22-24% not sure about that. We have three line on each oven and 8 passes for each lines. Do you have any experience with pumping systems and viscosity control? Thanks