JNewman

15kva induction forge capacity

Recommended Posts

I have an opportunity to pick up a 15kva induction forge for a good price.  My problem is I rarely forge anything less than 1" and the job I would really like induction for is 2" round.  This machine is definitly undersized but how long would it take to heat 2" of 2" round?   I want to drop it in and hit the go button while I am forging the previous slug not feed it in and out. 

Share this post


Link to post
Share on other sites

it will depend on how well the coil matches the work and the efficiency of the unit, for examples see the 'home built induction heater' thread for videos of that in use. there has been no activity on that though since last june when it was just about ready

Share this post


Link to post
Share on other sites

2 1/8"

 

largest i'd go with mine is about 3/4 ... otherwise its long time to heat

 

go for a bigger machine ..  25 or a 35 would be ideal

Share this post


Link to post
Share on other sites

I would guess 1.5 - 2.5 minutes per heat with a good fitting coil. You cannot go full on full power with that size, you have to soak it at a lower setting for longer as induction heats from the outside in. the fact that you are working a slug as opposed to the end of a bar makes all the difference, the machine should be enough.

I am amazed at how cheap the 15kva machines are on ebay. 1300 bucks shipped, jeez.

Share this post


Link to post
Share on other sites

I have a 15Kva heater. 2" solid square takes about 2 minutes. Set it in, turn it on, do something else.

 

A 25 or 35 just takes a little less time. Make your own coils with 1/4" copper, no problem.

 

Neil

Share this post


Link to post
Share on other sites

I will have to check how long the forging takes today.  If it takes 2 minutes to forge the previous piece then I am fine.   I am currently waiting on these to heat up using propane and I am burning a lot of propane. 

Share this post


Link to post
Share on other sites

The savings In fuel cost will be substantial. Even if the working time/heating times are close that's good enough for me. I always need seconds to do tasks in between heats when producing. You can always turn it down to get more time if you need it.

That's one of the best things about these machines. There is a rising time heat level (a rotary dial) and a corresponding timer, and then there is a retaining time also with a timer. For example you can set the rising time full blast for 60 seconds and then back the machine off to say one quarter power for 60 more seconds which saves in electricity but your part is still really hot and more importantly not burning when you need it. So useful, it turns you into a production machine, if you can keep up.

You will need a good water cooler with a big resivoir when working those chunks.

post-979-0-99280100-1423317742_thumb.jpg

Share this post


Link to post
Share on other sites

If you have 480 3 phase, we have a used 30kva unit at work for sale, $3,000. It is made by Radyne.

No 480 but I have 600v 3 phase and can get a transformer.  What is the frequency of the unit? 

Share this post


Link to post
Share on other sites

It does . You try to get the best coupling to the part, so small parts take smaller coils than bigger parts. We use different sizes at work depending on which contacts we need to anneal. The tubing on our coils have a square cross section, not round. There is some debate on which is better.

Share this post


Link to post
Share on other sites

BIGGUNDOCTOR, Did you get the specs on the 30kw machine?   I might be interested.   Might be down your way the end of April.  I have been using 3/16" tubing, it is easy to form.  When I started I was using 1/4" and read somewhere that folks were making coils with 3/16 so I thought it might be better to use.  What determines the size tubing you use.  I have a 15 and 25 kw unit.

 

 

Share this post


Link to post
Share on other sites

So going back to the question of capacity, is it a question of over-heating, duty cycle, or just speed that identifies the "capacity" of a particular machine? I mean, at some point, 15kw just isn't enough heat to offset the radiant and conductive heat loss, but in stock sizes that we're likely to see in open-die forging these days, what is the limiting factor?

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.