Pack carbing of low carbon steels. 1

[bob1111]

Per my other threads, we want to bring a carburize process in house for small volume work. Per our research, the ONLY one that seems safe enough to bring in is pack carbing by cooking the parts in a carbon rich powder and then either removing quickly for quenching in water or allowing to slow cool, remove from the carbon media, and follow up with a heat treat and temper.


We are trying to not only find some excellent resources for practicing this procedure, but also a resource for the packing product. We have talked with Park but not sure how many companies out there offer these products.

We have looked at Barium free packing products but thought maybe using Barium might still be acceptable and we would simply have to properly dispose of the product.

 

[TVP]

ASM HANDBOOK Volume 4 Heat Treating has an article on this method. You can download just this article for $20, or purchase the whole book for ~ $200. I'm not sure if there are any other suppliers for this type of material in the USA, so if you are happy so far with Park, I suggest continuing with them.

 

[arunmrao]

It is now a historical process,and only used for very large parts which cannot be carburized in more efficient furnaces. The results are varyingand inconsistent ,but however offers a simple,cheap ready solution. Propreitary packs are available .

Learn the rules,so you know how to break them properly.
Dalai Lama

_____________________________________

 

[redpicker]

Speaking of historical, some people know that Howard Hughes, Sr. operated a brewery (Gulf Coast Brewing; Grand Prize beer) on the grounds of Hughes Tool Company, in Houston, Tx. Fewer know that the spent grain from the brewery was used as the pack carburizing compound for the bearings on the rock bits manufactured by the Hughes Tool Company.

So, viper6383, maybe you need to just convince your boss that you need to start a brewery to insure a consistent source of raw material...

rp

 

[bob1111]

LOL, wouldn't you know it. We DO brew our own in 10gal batches!! Have been for about 3 yrs now. And to think we are just throwing away our mash mixture when we are done...


Can you guys offer any US sources for pack or liquid carburizing by chance?

 

[unclesyd]

I've used Wilcarbo from Rose Mill and several from Park Metallurgical, all with great success. I think the Park products will cover all your questions.

http://www.rosemill.com/default.asp?pageid=27391

http://www.heatbath.com/park/products/carburizing

There is a lot of good used heat treating equipment on the market now. I would call someone like Furnaces Brokers and discus your requirements.

http://www.furnacebrokers.com/

 

[bob1111]

I have not done any math as of yet but do you think a basic 6-8kw residential type kiln could work for smaller runs? Even if we cannot make this case harden deal work, I would still like to bring our smaller run 4XXX series jobs in for through hardening.

I am guessing though that we will need to bring our parts up to temp a bit quicker than maybe a residential kiln could do.

 

[redpicker]

Do yourself a favor and look for a real heat treating furnace (google Lucifer furnaces), particularly one with an over/under high temp/temper chambers. You need to do this right, not play at it. Otherwise, use an outside heat treating vendor who has the proper equipment. Having used both residential kilns and small heat treating furnaces, I can tell you that trying to heat treat in a kiln is like trying to swim in a bath tub.

And, as a homebrewer for 15 years, I can say that if you're throwing away your spent mash, you are wasting it. Feed it to horses (they love it), compost it (I haven't found anything that composts faster), or dry it and use it for pack carburizing compound, but don't throw it away

(I interviewed for a job at HTC over 20 years ago, which is where I got the above info--they had closed the brewery by then, but they still had the buildings of the beer garden. The guy who interviewed me told me that, back in the day, they served the beer at lunch and after their shift was over, workers would stop off for a beer before going home. Imagine a situation like that today!).

 

[unclesyd]

I gave you the url for liquid carburizing compounds instead of pack carburizing compounds.

I second the suggestion by redpicker, even though it might work I wouldn't use a residential pottery kiln.

http://www.heatbath.com/park/products/pack_carburizing_compounds