New to the Steel Casting Industry 5

[amcneal]

Hello,

I am a new Welding Engineer at a steel casting company. I work with very large steel castings and I run into various issues with cracking (under risers, in the casting, etc.) We remove our castings with oxy-fuel torches and I have a sneaking suspicion that the heat input from this removal method is the main cause for cracking under our risers. However, I need to have more than just a hunch to implement any changes, change is fought at every turn here at my lovely foundry .

Anyway, I was wondering if any of you more experienced people in the industry could point me in a solid direction of reference material regarding steel castings, and the problems associated with large industrial castings. For example, I have a great book for welding stainless steels called "Stainless Steel Welding Metallurgy" it is a great book. It describes many of the cracking mechanisms for the various grades of stainless steels and potential fixes for said problems.

Thanks in advance,

Anthony

 

[arunmrao]

Under riser crackimg in heavy risers is as a result of segregation. You need to normalize the castings,before you undertake flame cutting. This will certainly reduce the incidence of cracking.

Please find Steel Castings Handbook from SFSA (Steel Founders Society of America) and few free online publications from their website

http://wwww.sfsa.org.

_____________________________________
"It's better to die standing than live your whole life on the knees" by Peter Mayle in his book A Good Year

 

[mw1st]

Normalizing casting prior riser removal may help, but will not solve the problem. Besides, why would one want to waste oven resources, heat treating risers (castings with risers still attached)? One solution is to cut off the riser with high rpm chop off saw. This is what we do in our foundry regardless of steel type (stainless, plain or high alloy steel) and riser neck size, (maximum we cut is 10'' dia. riser neck) Furthermore, you end up with nice clean cut, with a part requiring little finishing ie. grinding the remainder of the riser neck. I'm not sure if it's more time consuming then using torches, most important is defect free casting.

Mark

 

[LiquidSteel]

We make heavy walled steel parts and we've found that sometimes the parts can crack from sitting around too long before their first heat treatment. Residual stresses due to macro segregation in the midwall.