08-30-2013, 06:16 PM
Back in my steelworks days we used to make very good use of White Iron or as we called it chilled Iron, Melting iron was never a problem for us as we got 210tons every 42 minutes out of our very own pair of blast furnaces. we'd average 19 heats a day counting in down time etc.
At any rate we used to cast a lot of stuff directly into the floor of the foundry which was eighty years deep with greensand pits and old moulds and punctuated with railway lines and jib crane posts for bringing in torpedo ladles and lifting out patterns and rough castings.
When casting new pot ladles, which were good for holding 50+ tons of cast iron or steel after lining we used to "Chill" the lifting lugs on purpose, it is easier than you might first think, all that needs doing is adding big ole copper plates called "Chills" or sometimes "Clinkers" or large disc shaped items with a central Leg on the back, the chills were added just after the first layer of fine sand was laid over the pattern, keeping in mind the size of the patterns the fine sand layer moght have been about an inch thick, then the chils are layed into it and tamped down then the coarse sand went in on top, this way certain areas of the mould conducted the heat away very rapidly causing, well..."Chilled" spots that allowed the areas to wear far better than grey iron ever could.
Incidentally the pots I'm thinking of were cast in three or four rings and then welded together and then welded to a base, each ring was about six feet in diameter and two to three feet high/deep, It was great to watch a pour we used to control pouring temperature to an accuracy of plus or minus four degrees c and for good chilling use about twenty degrees of super heat, I'd guess the chilling seen above was the result of a cold pour, but it could have been many things.
Regards
Rick
At any rate we used to cast a lot of stuff directly into the floor of the foundry which was eighty years deep with greensand pits and old moulds and punctuated with railway lines and jib crane posts for bringing in torpedo ladles and lifting out patterns and rough castings.
When casting new pot ladles, which were good for holding 50+ tons of cast iron or steel after lining we used to "Chill" the lifting lugs on purpose, it is easier than you might first think, all that needs doing is adding big ole copper plates called "Chills" or sometimes "Clinkers" or large disc shaped items with a central Leg on the back, the chills were added just after the first layer of fine sand was laid over the pattern, keeping in mind the size of the patterns the fine sand layer moght have been about an inch thick, then the chils are layed into it and tamped down then the coarse sand went in on top, this way certain areas of the mould conducted the heat away very rapidly causing, well..."Chilled" spots that allowed the areas to wear far better than grey iron ever could.
Incidentally the pots I'm thinking of were cast in three or four rings and then welded together and then welded to a base, each ring was about six feet in diameter and two to three feet high/deep, It was great to watch a pour we used to control pouring temperature to an accuracy of plus or minus four degrees c and for good chilling use about twenty degrees of super heat, I'd guess the chilling seen above was the result of a cold pour, but it could have been many things.
Regards
Rick
Whatever it is, do it today, Tomorrow may not be an option and regret outlasts fatigue.