Induction heaters...

[David Lesher]

I\'ve seen mechanics using induction heaters such as
<https://acura.snapon.com/HondaAcura/Catalog/Product/INIMD-700A>
for loosening stuck bolts.

I\'ve seen them work and seriously lust after such.
But not at the prices they go for.

What frequency do they run at? Power level?


--
A host is a host from coast to coast.................wb8foz@nrk.com
& no one will talk to a host that\'s close..........................
Unless the host (that isn\'t close).........................pob 1433
is busy, hung or dead....................................20915-1433

 

[bitrex]

On 8/1/2020 4:27 PM, David Lesher wrote:

I\'ve seen mechanics using induction heaters such as
https://acura.snapon.com/HondaAcura/Catalog/Product/INIMD-700A
for loosening stuck bolts.

I\'ve seen them work and seriously lust after such.
But not at the prices they go for.

What frequency do they run at? Power level?

You could try the eBay special:

<https://www.ebay.com/itm/1000W-ZVS-20A-Voltage-Induction-Heating-Board-Module-Flyback-Driver-Heater-US/173183297050?hash=item285287661a:g:4gYAAOSwtypalR-~>

 

[Joe Gwinn]

On Sat, 1 Aug 2020 20:27:03 +0000 (UTC), David Lesher
<wb8foz@panix.com> wrote:

I\'ve seen mechanics using induction heaters such as
https://acura.snapon.com/HondaAcura/Catalog/Product/INIMD-700A
for loosening stuck bolts.

I\'ve seen them work and seriously lust after such.
But not at the prices they go for.

What frequency do they run at? Power level?

About 30 KHz. Varies, but hundreds of watts.


See <http://www.johndearmond.com/category/induction-heating/>.

He publishes his circuits.

He was a founder of Fluxeon: <https://fluxeon.com/>.

Joe Gwinn

 

[Tim Williams]

\"David Lesher\" <wb8foz@panix.com> wrote in message
news:rg4j6n$ce1$1@reader1.panix.com...

I\'ve seen mechanics using induction heaters such as
https://acura.snapon.com/HondaAcura/Catalog/Product/INIMD-700A
for loosening stuck bolts.

I\'ve seen them work and seriously lust after such.
But not at the prices they go for.

What frequency do they run at? Power level?

I don\'t know that one in detail, but I would guess 50-200kHz and under 1kW.
And at a Q up to 10 or so, probably.

Reactive power is a huge performance factor for induction heating: it\'s how
much distance you can have between coil and work, and what kind of materials
you can heat. Same performance factor as wireless charging and whatnot, and
for the same reason -- you need to resonate out all the leakage inductance
between coil and work.

Low Q is basically only for tight fitting coils and ferrous metals up to (or
maybe a little bit beyond) Curie temperature. Great for loosening bolts,
not so great for say, brazing carbide.

And not nearly enough power for, say, case hardening, or levitation melting,
if you want to get into specialized applications.

Tim

--
Seven Transistor Labs, LLC
Electrical Engineering Consultation and Design
Website: https://www.seventransistorlabs.com/

 

[Jan Panteltje]

On a sunny day (Sat, 1 Aug 2020 16:32:35 -0400) it happened bitrex
<user@example.net> wrote in <CjkVG.36601$5l1.7278@fx10.iad>:

On 8/1/2020 4:27 PM, David Lesher wrote:
I\'ve seen mechanics using induction heaters such as
https://acura.snapon.com/HondaAcura/Catalog/Product/INIMD-700A
for loosening stuck bolts.

I\'ve seen them work and seriously lust after such.
But not at the prices they go for.

What frequency do they run at? Power level?




You could try the eBay special:

https://www.ebay.com/itm/1000W-ZVS-20A-Voltage-Induction-Heating-Board-Module-Flyback-Driver-Heater-US/173183297050?hash=item285
287661a:g:4gYAAOSwtypalR-~

Yea, I have one like that from ebay, used for many experiments.
Even baking eggs.
http://panteltje.com/pub/inductive_heater_current_spiral_coil_with_metal_lid_IMG_5208.JPG
melting solder on a metal plate with home made flat coil.

Those things have a nice clean sinewave output.

Useful for many things:
http://panteltje.com/pub/crucible_with_molten_solder_IMG_5439.JPG

 

[Cydrome Leader]

bitrex <user@example.net> wrote:

On 8/1/2020 4:27 PM, David Lesher wrote:
I\'ve seen mechanics using induction heaters such as
https://acura.snapon.com/HondaAcura/Catalog/Product/INIMD-700A
for loosening stuck bolts.

I\'ve seen them work and seriously lust after such.
But not at the prices they go for.

What frequency do they run at? Power level?




You could try the eBay special:

https://www.ebay.com/itm/1000W-ZVS-20A-Voltage-Induction-Heating-Board-Module-Flyback-Driver-Heater-US/173183297050?hash=item285287661a:g:4gYAAOSwtypalR-~

I\'d second these things. The only goofy part is if the input voltage gets
too low (maybe 10 or even 11 volts) they latch up. So, if you try to run
it off a 12 volt lead acid battery, you have a good chance of the thing
running poorly on a weak battery or with power cables that are too thin.
It\'s obvious when it latches up too- the output stops and the heatsinks
get burning hot real fast. They normally run cool enough to touch. The
copper inductor will heat up fast if you have no load as well.

 

[Joe Gwinn]

On Sun, 2 Aug 2020 00:01:40 -0500, \"Tim Williams\"
<tiwill@seventransistorlabs.com> wrote:

\"David Lesher\" <wb8foz@panix.com> wrote in message
news:rg4j6n$ce1$1@reader1.panix.com...
I\'ve seen mechanics using induction heaters such as
https://acura.snapon.com/HondaAcura/Catalog/Product/INIMD-700A
for loosening stuck bolts.

I\'ve seen them work and seriously lust after such.
But not at the prices they go for.

What frequency do they run at? Power level?

I don\'t know that one in detail, but I would guess 50-200kHz and under 1kW.
And at a Q up to 10 or so, probably.

Frequency depends on the size of the object to be heated, and if one
is trying to heat only the surface, or to go deeper.

The INIMD-700A mentioned above is for loosening bolts and expanding
bearing races in an auto repair shop, so its frequency will be lowish.
Was it 50 KHz? I think I saw that somewhere.

Reactive power is a huge performance factor for induction heating: it\'s how
much distance you can have between coil and work, and what kind of materials
you can heat. Same performance factor as wireless charging and whatnot, and
for the same reason -- you need to resonate out all the leakage inductance
between coil and work.

Low Q is basically only for tight fitting coils and ferrous metals up to (or
maybe a little bit beyond) Curie temperature. Great for loosening bolts,
not so great for say, brazing carbide.

And not nearly enough power for, say, case hardening, or levitation melting,
if you want to get into specialized applications.

Yes to all. Neon John recommended a book from the industrial world on
all such things:

\"Elements of Induction Heating -- Design, Control, and Applications\",
S. Zinn and S. L. Semiatin, EPRI, ASM International, 1988, 35 pages,
ISBN 0-87170-308-4. This book was commissioned by EPRI.

This cost $35 on Amazon in 2017; the price is more like $100 now, and
I assume that it\'s now out of print. My copy is from the Fifth
Printing in March 1998.


Joe Gwinn

 

[Phil Hobbs]

On 2020-08-01 18:56, Joe Gwinn wrote:

On Sat, 1 Aug 2020 20:27:03 +0000 (UTC), David Lesher
wb8foz@panix.com> wrote:

I\'ve seen mechanics using induction heaters such as
https://acura.snapon.com/HondaAcura/Catalog/Product/INIMD-700A
for loosening stuck bolts.

I\'ve seen them work and seriously lust after such.
But not at the prices they go for.

What frequency do they run at? Power level?

About 30 KHz. Varies, but hundreds of watts.


See <http://www.johndearmond.com/category/induction-heating/>.

He publishes his circuits.

He was a founder of Fluxeon: <https://fluxeon.com/>.

Joe Gwinn

Neon John used to be a regular here. He moved into an assisted-living
place back in February and hasn\'t posted since. Hope he\'s OK.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
http://hobbs-eo.com

 

[Tim Williams]

\"Joe Gwinn\" <joegwinn@comcast.net> wrote in message
news:escdif9uk1ppe1tpe4eni3303hkp0hp7re@4ax.com...

Frequency depends on the size of the object to be heated, and if one
is trying to heat only the surface, or to go deeper.

In an optimized application, yes -- I highly doubt they are so discerning,
and they certainly can\'t afford to run the frequency too low (<= 10kHz say?)
as that would require more capacitors than fit inside the thing, and it
doesn\'t matter at all with the low heat flux.

The INIMD-700A mentioned above is for loosening bolts and expanding
bearing races in an auto repair shop, so its frequency will be lowish.
Was it 50 KHz? I think I saw that somewhere.

It\'s going to be low enough that switching isn\'t annoying, and high enough
that capacitating isn\'t annoying.

\"Elements of Induction Heating -- Design, Control, and Applications\",
S. Zinn and S. L. Semiatin, EPRI, ASM International, 1988, 35 pages,
ISBN 0-87170-308-4. This book was commissioned by EPRI.

This cost $35 on Amazon in 2017; the price is more like $100 now, and
I assume that it\'s now out of print. My copy is from the Fifth
Printing in March 1998.

Yup, very informative.

Tim

--
Seven Transistor Labs, LLC
Electrical Engineering Consultation and Design
Website: https://www.seventransistorlabs.com/

 

[Joe Gwinn]

On Sun, 2 Aug 2020 16:48:35 -0400, Phil Hobbs
<pcdhSpamMeSenseless@electrooptical.net> wrote:

On 2020-08-01 18:56, Joe Gwinn wrote:
On Sat, 1 Aug 2020 20:27:03 +0000 (UTC), David Lesher
wb8foz@panix.com> wrote:

I\'ve seen mechanics using induction heaters such as
https://acura.snapon.com/HondaAcura/Catalog/Product/INIMD-700A
for loosening stuck bolts.

I\'ve seen them work and seriously lust after such.
But not at the prices they go for.

What frequency do they run at? Power level?

About 30 KHz. Varies, but hundreds of watts.


See <http://www.johndearmond.com/category/induction-heating/>.

He publishes his circuits.

He was a founder of Fluxeon: <https://fluxeon.com/>.

Joe Gwinn


Neon John used to be a regular here. He moved into an assisted-living
place back in February and hasn\'t posted since. Hope he\'s OK.

I do remember when he posted, and then (if I recall) his health
started to fail, and he retired. I don\'t know if he is OK. Does
anybody know?

Joe Gwinn